Page 2 of 2 FirstFirst 1 2
Results 26 to 50 of 50

Thread: Boost limiters

  1. #26
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    one more
    Attached Images Attached Images
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  2. #27
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Quote Originally Posted by MonaDeRio View Post
    I got the valve today and here are some pix. I took it apart and I don't get how it work. Can anyone explain it to me? I thought the valve should be near inlet then spring. 928 motosports has inlet- ball valve - spring-6 holes outlet. I have inlet-spring-valve-outlet.
    Is something wrong?
    Can that black valve part fit in the inlet side? I remember seeing that it could work for vacuum or pressure, so it may just be designed to have the guts reversed for pressure.

  3. #28
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    You are absolutely right. It could be reversed. My bad. So time to make 6 holes. It's possible to fabricate the heat resistance valve but it will take time.
    Attached Images Attached Images
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  4. #29
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    I'm done with the holes. Tomorrow get it to the shop and adjust to 12 PSI. I found this on eBay http://thespeedfreaks.net/showthread...ackets-5-2-5-9

    It fits but too big. Found more http://www.shoppumps.com/Wilden-08-1...08-1080-51.htm

    Here we go useful link http://www.jjshort.com/Rubber-Properties.php


    DSCN0947.jpg
    Last edited by MonaDeRio; 01-13-2015 at 01:18 PM.
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  5. #30
    sfn's lonely vajay jay
    Join Date
    Apr 2014
    Location
    West Chester, PA
    Posts
    431
    Rep Power
    89
    When I had manual boost controllers the standard valve ball was steel. The upgrade was ceramic. Not sure if this helps your choice...

    P.S. You found the s/c brackets I got made on eBay? LOL
    - Sandy

  6. #31
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Eddie- you thinking about replacing that plastic valve with a rubber ball? I'd use something harder
    Those $192 ones from 928 used teflon balls (pretty hard), and it's actually a good material for the application. You can find them in many sizes on ebay for under $7 shipped from China - just search for " teflon diaphragm ball ", and you should be able to find the size you need.

    Funny Sandy mentioned ceramic because that's what I planned to use in my home-brew one... just because I can! Thought I might use a titanium spring too, just to be hoitie-toitie, like I'm making a boost valve for a friggin' Ferrari!

  7. #32
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    Quote Originally Posted by carlmon View Post
    Eddie- you thinking about replacing that plastic valve with a rubber ball? I'd use something harder
    Those $192 ones from 928 used teflon balls (pretty hard), and it's actually a good material for the application. You can find them in many sizes on ebay for under $7 shipped from China - just search for " teflon diaphragm ball ", and you should be able to find the size you need.

    Funny Sandy mentioned ceramic because that's what I planned to use in my home-brew one... just because I can! Thought I might use a titanium spring too, just to be hoitie-toitie, like I'm making a boost valve for a friggin' Ferrari!
    Thanks for the teflon balls input. I found those on eBay and I'll find out which size is the best. I could use viton o-ring and fabricated brass valve as well but the teflon balls is the easier way. I'm just testing which route is the best.
    I discovered one thing the plastic piece goes with black o-ring. If I'll replace this with viton o-ring maybe I don't need to do anything. Am I right. I don't know if that black plastic piece is heat resistance enough.

    DSCN0951.jpg

    16mm teflon ball will be fine. I found them here http://www.mcmaster.com/#9660k26/=vggv0a
    Last edited by MonaDeRio; 01-13-2015 at 07:54 PM.
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  8. #33
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Quote Originally Posted by MonaDeRio View Post
    Thanks for the teflon balls input. I found those on eBay and I'll find out which size is the best. I could use viton o-ring and fabricated brass valve as well but the teflon balls is the easier way. I'm just testing which route is the best.
    I discovered one thing the plastic piece goes with black o-ring. If I'll replace this with viton o-ring maybe I don't need to do anything. Am I right. I don't know if that black plastic piece is heat resistance enough.
    I was originally thinking you should just replace that o-ring, but while some plastics can certainly handle the heat, we don't know about that one. As low as the chance is that it could be ingested into your motor, I wouldn't take the risk. I'd just try that teflon ball. You will probably lose you ability to adjust it to zero since the ball is taller, but that shouldn't bother you.

  9. #34
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    I need to make the aluminum copy of that plastic thing.
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  10. #35
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    I put the Viton O-ring instead of Buna-N. I have also 3/4" Teflon ball and it works fine but I prefer Viton O-ring. Just need to weld the bung to the discharge tube and set the valve to 12 PSI.

    DSCN0954.jpg
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  11. #36
    SCT Tuning Guru
    Join Date
    Apr 2013
    Posts
    150
    Rep Power
    2226
    You guys can't be serious with this crap.

    First off, find a crowbar, then take it to your wallet. If you insist on doing it, use a wastegate, not some BS checkvalve dealio. Ebay wastegates are not that expensive. If the price of a wastegate from China's finest is going to break you, you probably have no business doing this in the first place.

    Next. The V1/V2 blowers are not the best as far as managing IATs, the cramped ZJ engine bay does not help things at all. I finished a V1'd Dakota with a 58mm TB,M1 4bbl, ported heads, small cam (Cali special), and a V1 with a 3.125 pulley. 10 psi, intercooled, and we were still seeing 140-150*F temps. I assure you you will amplify the problem with a wastegated setup, to the point of having to pull timing just to make it not detonate. Meaning you will ultimately spend more money for negligible/no difference.

    Then you have the issue on belt slip. Even with the Sandra brackets, I do anticipate the smaller pulleys slipping.

    I ran the math on Eddie's V2 setup. At 6000 rpms he will be overspinning maximum impeller rpm by 10000 RPM. That is 20 PERCENT beyond most of the various V2 trims. Such operation will result in destroyed bearings, terrible compressor efficiency, and IATs off the charts. The problem is not masked by simply reducing shift points, as you are leaving HP off of the table. Even with a 2.7 or 2.75 pulley the blower is still being overspun at that kind of rpm.

    On the note of headgaskets. On a 360 the norm for piston height at TDC is .030 to .060 below the deck. I have heard of variances from anywhere from .010 to .100. You want to keep your quench especially on a stock bottom end to an absolute minimum. So, if zero-decking or block milling is not a viable choice, compensate for the less than optimal quench by using a thinner headgasket. Yes, you are increasing compression by doing so but tightening the quench will make a given configuration less likely/prone to detonation. Most of you could probably get away with using a thinner headgasket because very few of you are running camshafts that run close to P2V tolerances. I have typically used the 1008s.

    *mic drop*
    Last edited by FlyinRyan; 01-22-2015 at 07:21 AM.
    Always outmanned...Never outgunned

  12. #37
    RallyJeep GO
    Join Date
    Jan 2010
    Location
    Rochester, NY
    Posts
    4,328
    Rep Power
    137
    Ryan has some good points. On some setups, running a bigger blower will be necessary to gain anything useful with a wastegate without over-spinning the blower and damaging it, or just driving the IATs through the roof. It also does require a GOOD intercooler setup.
    1998 ZJ 5.9 Limited - Deep Slate
    Mods: Big trans cooler, 231 swap, Indy 2.02 heads prepped by IMM, Comp 20-744-9 cam, 1.7 HS roller rockers, 52mm TB, Airgap manifold, DT headers and full 3" exhaust, SCT tune homebrewed by me, Martin Saine valve body, B&M tranny pan, magic suspension made from unicorn tears, power steering cooler, lots of lighting mods

  13. #38
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Quote Originally Posted by FlyinRyan View Post
    You guys can't be serious with this crap.

    First off, find a crowbar, then take it to your wallet...

    Next. The V1/V2 blowers are not the best as far as managing IATs, the cramped ZJ engine bay does not help things at all. I finished a V1'd Dakota with a 58mm TB,M1 4bbl, ported heads, small cam (Cali special), and a V1 with a 3.125 pulley. 10 psi, intercooled, and we were still seeing 140-150*F temps. I assure you you will amplify the problem with a wastegated setup, to the point of having to pull timing just to make it not detonate. Meaning you will ultimately spend more money for negligible/no difference.

    Then you have the issue on belt slip. Even with the Sandra brackets, I do anticipate the smaller pulleys slipping.

    I ran the math on Eddie's V2 setup. At 6000 rpms he will be overspinning maximum impeller rpm by 10000 RPM.

    On the note of headgaskets. On a 360 the norm for piston height at TDC is .030 to .060 below the deck. I have heard of variances from anywhere from .010 to .100. You want to keep your quench especially on a stock bottom end to an absolute minimum. So, if zero-decking or block milling is not a viable choice, compensate for the less than optimal quench by using a thinner headgasket. Yes, you are increasing compression by doing so but tightening the quench will make a given configuration less likely/prone to detonation.

    *mic drop*
    *mic pickup*
    Yes, we're serious with this crap. If nothing else, it's an experiment that can be easily undone, and the joy of tinkering is half of the reason to modify a perfectly good Jeep.

    My goal is not peak power at 6000 RPM, it's to have a better torque curve across the whole RPM band for normal driving, where centrifugal superchargers are less than ideal. I think if you look at it from this perspective you will see some reason in what I'm talking about. I respect your knowledge and experience, but I suspect you're used to satisfying customers who care about impressive peak numbers. I'm not a number chaser- I don't care if I ever know what my peak HP is, I care much more how the torque curve looks below the peak, and care even more how good it is to drive.

    It doesn't sound expensive to me. I'll be well over $2,000 in parts alone (not including the supercharger) for what I consider necessary to run the SC correctly... intake manifold, TB, A-W intercooler, heat exchanger etc., so another $200 for a part, even if it turns out to be a failed experiment is a drop in the bucket. Money has nothing to do with whether I'll choose a limiter valve or wastegate- it's a question of which would do the job better and more reliably. I could be wrong, but I believe the spring-loaded ball valve would meter the pressure more accurately, and would certainly be more reliable because of its simplicity.

    IATs- first, I'm planning a good intercooler setup with a forced air heat exchanger, and external source cold air intakes to the compressor and heat exchanger. Second, I'm NOT going to over-rev the impeller. I'm not planning to ever run to 6,000 RPM (and I think Eddie isn't either), and high RPM is where IAT and compressor inefficiency builds. At 5200, impeller RPM is right at 50,200 on a V1 with 2.5" pulley (V2 would be a little higher at 52,400). Granted, it would be a bad idea to run at that speed much, but I simply don't drive my Jeep like that. My Jeep lives between 2000 and 4500, or 3000-4700 if I'm into it.

    Belt slip: Eddie and I are both planning to run an extra pulley between the alternator and supercharger that will increase pulley wrap by about 30%, not just the extra notch for the tensioner on Sandy's brackets. I'm not totally convinced it will completely eliminate slip on a 2.5" pulley, but it only takes 15 minutes and $80 to switch to 2.7" if it does.

    Head Gaskets: This bit is very interesting to me. Before I decided to go the SC route I had planned a half-height gasket, but abandoned it to avoid elevating compression. I don't quite understand why getting closer to zero deck is better for quench, but I'll read up on it. A thinner gasket would also be less prone to blowout, so has a dual benefit.

  14. #39
    Member
    Join Date
    Mar 2012
    Location
    Ausin, TX
    Posts
    2,111
    Rep Power
    4412
    Quote Originally Posted by carlmon View Post
    My goal is not peak power at 6000 RPM, it's to have a better torque curve across the whole RPM band for normal driving, where centrifugal superchargers are less than ideal. I think if you look at it from this perspective you will see some reason in what I'm talking about. I respect your knowledge and experience, but I suspect you're used to satisfying customers who care about impressive peak numbers. I'm not a number chaser- I don't care if I ever know what my peak HP is, I care much more how the torque curve looks below the peak, and care even more how good it is to drive.
    This is all I will speak on here and all I will say is you are assuming almost 100% the exact opposite of the way he tunes. Torque curve and driveability is his number one concern which is why I recommend it as the very very very first mod for people to do. Peak numbers are rad though so why not have both?
    '98 Grand 5.9 "Black Pearl" totaled
    '98 Grand 5.9 "Eleanoir"
    "No Officer, all four tire tracks are mine, it WAS all wheel drive......yes ma'am Im aware this structure is normally used to 'park' cars"

  15. #40
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Quote Originally Posted by lilbullie5.9 View Post
    This is all I will speak on here and all I will say is you are assuming almost 100% the exact opposite of the way he tunes. Torque curve and driveability is his number one concern which is why I recommend it as the very very very first mod for people to do. Peak numbers are rad though so why not have both?
    I should clarify- I meant to imply nothing about the way Ryan tunes. I hope he tunes mine because he obviously knows what he's talking about, and I have respect for him. He's the man. He knows more than I do about making Jeeps go fast (as do many speedfreaks). I just meant that when he was talking about 6000 RPM he was talking about something I'm not looking for, and my engine can't do. Eddie and I had discussed our max RPMs extensively, and I think Ryan must not have read it.

    If (when) I rebuild my lower, then I might get higher RPM heads (aluminum Edelbrocks), cam and torque converter, and pulley up an appropriate amount... but for now, this is the way to make the most of my motor's physical RPM and air flow limitations. Even Ryan can't tune better than a motor's physical limitations!

  16. #41
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    I'm running on my SC RHP 7003CTDULP4 ABEC 7 Super Precision Angular Contact bearings with the (oil)speed limit 50500. So at 5000 rpm I won't hurt my SC with the 2.5" pulley.
    What pulley should I install to run 6000 RPM without any problems?
    Last edited by MonaDeRio; 01-23-2015 at 06:35 PM.
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  17. #42
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Assuming you're running V1, a 2.9" would be just under 50k impeller RPM at 6000 motor RPM. A 2.8" would give you 51,750. I'd under-drive mine rather than push it, but 2.7" would give you just under 54,000. It's not just the bearings that are at risk- it's the cast impeller that can't take abuse as much as billet impellers, and I'd hate to see your motor ingest bits of impeller metal. Also, it's the extra heat generated by running above the design, just as Ryan said.

    If you run it above 50k you're dropping below 65% efficiency, and that efficiency loss is going into heat, and the heat will cost you any gain you get from more boost at that point. This is exactly what Ryan was talking about, having to pull timing.
    My motor is nothing like yours (stock heads, cam and bottom end), but if I had your motor I would want two SCT programs, one with the smaller pulley in mind with the revs limited and shift points lowered for around town drivability, and one for a 2.9 pulley to rev to 6000 and higher shift points for when the gloves come off. It's so easy to switch a pulley, why have just one setup?

    Here's the calculator for impeller speed - V1 is at the bottom:
    http://www.vortechsuperchargers.com/page.php?id=33511
    You just put in the crank pulley size, RPM shift point (or max RPM), and pulley size.
    Here's the S-Trim compressor map:
    http://www.vortechsuperchargers.com/maps/s-trim_map.gif
    You can see over 50k is off the chart - it's just not designed to spin that fast, regardless of bearings. Better bearings will make it last longer and run a little cooler at any given RPM.

  18. #43
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    Thanks for the links. I have V2 SC.
    Crank OD -7.25"
    6000 rpm
    Pulley 3.12 (that comes with the Vortech set for Jeep)
    -----------------------------------------------------------
    Impeller speed 50192.31
    It will be safe.

    My engine is nothing special.
    I have the stock bottom end as well.
    Only the upper part of the engine is highly modified plus SC.
    So I have to be careful to play with the high boost.
    Last edited by MonaDeRio; 01-23-2015 at 08:14 PM.
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  19. #44
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Quote Originally Posted by MonaDeRio View Post
    Thanks for the links. I have V2 SC.
    Crank OD -7.25"
    6000 rpm
    Pulley 3.12 (that comes with the Vortech set for Jeep)
    Impeller speed 50192.31
    It will be safe.

    My engine is nothing special. I have the stock bottom end as well.
    Only the upper part of the engine is highly modified plus SC.
    So I have to be careful to play with the high boost.
    Don't sell your engine short... cam and heads makes a huge difference!
    7.25" crank pulley- is that the new one you were getting? Stock is 7". Either way, the 3.12 sounds good with limiters off. I missed that you had the V2... it's geared up a bit more. Even with the 3.12 the boost limiter valve will come into play.
    With the V2, even with revs limited to 5200, it looks like you shouldn't go smaller than 2.7", but the 2.5" should still be good for the V1 I'm getting.
    I'd buy your 2.5" pulley if you still have it and want to sell it- if you do, PM me.

  20. #45
    Eddie MonaDeRio's Avatar
    Join Date
    Oct 2010
    Location
    Brooklyn, NY
    Posts
    1,957
    Rep Power
    126
    Quote Originally Posted by carlmon View Post
    Don't sell your engine short... cam and heads makes a huge difference!
    7.25" crank pulley- is that the new one you were getting? Stock is 7". Either way, the 3.12 sounds good with limiters off. I missed that you had the V2... it's geared up a bit more. Even with the 3.12 the boost limiter valve will come into play.
    With the V2, even with revs limited to 5200, it looks like you shouldn't go smaller than 2.7", but the 2.5" should still be good for the V1 I'm getting.
    I'd buy your 2.5" pulley if you still have it and want to sell it- if you do, PM me.
    You are right the crank pulley is 7". I'm running at low rpm all the time so 2.5" doesn't hurt the engine and add some performance.
    I bought the 2.5" pulley 8 rib natural finish from 928 motosports a few weeks ago for $82 shipped. Never installed.
    I would sell it to you for $75 shipped if you want. I realized that 2.5" pulley could hurt the SC on high rpm even if I'm driving slowly but sometimes not..


    DSCN0970.jpg DSCN0971.jpg DSCN0972.jpg

    New calculation

    Crank 7
    engine rpm 5400
    Pulley 2.7"
    impeller speed 50400.
    Looks like 5400 rpm is my red line for SC.
    Last edited by MonaDeRio; 01-24-2015 at 11:06 AM.
    SCT X3. Custom cam. Crane gold race roller rockers. Fully ported 2.02 R/T heads.. Mike Leach Headers. Full 3" cat back exhaust. Custom full return fuel system. Aeromotive 340 in-tank fuel pump. Aeromotive dual port adjustable fuel regulator. Holley 2 x 52mm TB. High stall torque converter 2800 . 24# Bosch Ford Racing injectors. MSD ignition box and coil.

    --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  21. #46
    SCT Tuning Guru
    Join Date
    Apr 2013
    Posts
    150
    Rep Power
    2226
    Quote Originally Posted by carlmon View Post
    *mic pickup*
    Yes, we're serious with this crap. If nothing else, it's an experiment that can be easily undone, and the joy of tinkering is half of the reason to modify a perfectly good Jeep.

    Any tuner worth their salt will charge you extra for your "experiments", especially when said experiments deviate from their own advice.


    My goal is not peak power at 6000 RPM, it's to have a better torque curve across the whole RPM band for normal driving, where centrifugal superchargers are less than ideal. I think if you look at it from this perspective you will see some reason in what I'm talking about. I respect your knowledge and experience, but I suspect you're used to satisfying customers who care about impressive peak numbers. I'm not a number chaser- I don't care if I ever know what my peak HP is, I care much more how the torque curve looks below the peak, and care even more how good it is to drive.

    Carl- I will get right to the point- there is nothing to be gained from overspinning (regardless of blower rpm) a blower of this size, on an engine of this displacement. Not when you can bridge the gap by maximizing belt wrap, minimizing belt slip, and maximizing airflow in the form of intake manifold, and TB, etc etc.


    It doesn't sound expensive to me. I'll be well over $2,000 in parts alone (not including the supercharger) for what I consider necessary to run the SC correctly... intake manifold, TB, A-W intercooler, heat exchanger etc., so another $200 for a part, even if it turns out to be a failed experiment is a drop in the bucket. Money has nothing to do with whether I'll choose a limiter valve or wastegate- it's a question of which would do the job better and more reliably. I could be wrong, but I believe the spring-loaded ball valve would meter the pressure more accurately, and would certainly be more reliable because of its simplicity.
    I'll trust Tial or even the Ching Chong equivalent before relying on McMaster Carr for boost control. I do not have time to waste on parts that don't work.

    IATs- first, I'm planning a good intercooler setup with a forced air heat exchanger, and external source cold air intakes to the compressor and heat exchanger. Second, I'm NOT going to over-rev the impeller. I'm not planning to ever run to 6,000 RPM (and I think Eddie isn't either), and high RPM is where IAT and compressor inefficiency builds. At 5200, impeller RPM is right at 50,200 on a V1 with 2.5" pulley (V2 would be a little higher at 52,400). Granted, it would be a bad idea to run at that speed much, but I simply don't drive my Jeep like that. My Jeep lives between 2000 and 4500, or 3000-4700 if I'm into it.
    Fact of the matter is that a centri SC still makes power to 6k on a stock long block. I went through my notes and tune repository and found a Vortech'd Ram I did. Headers, exhaust, M1, and a V2. I shifted it at 5400 due to valve float on stock valve springs, but the rest of the configuration could sustain 6000 rpms.
    Intercooler or not , the point remains the same, it's simply not a good idea.



    Quote Originally Posted by carlmon View Post
    I should clarify- I meant to imply nothing about the way Ryan tunes. I hope he tunes mine because he obviously knows what he's talking about, and I have respect for him. He's the man. He knows more than I do about making Jeeps go fast (as do many speedfreaks). I just meant that when he was talking about 6000 RPM he was talking about something I'm not looking for, and my engine can't do. Eddie and I had discussed our max RPMs extensively, and I think Ryan must not have read it.

    If (when) I rebuild my lower, then I might get higher RPM heads (aluminum Edelbrocks), cam and torque converter, and pulley up an appropriate amount... but for now, this is the way to make the most of my motor's physical RPM and air flow limitations. Even Ryan can't tune better than a motor's physical limitations!
    What limitations are you talking about?

    Quote Originally Posted by carlmon View Post
    My motor is nothing like yours (stock heads, cam and bottom end), but if I had your motor I would want two SCT programs, one with the smaller pulley in mind with the revs limited and shift points lowered for around town drivability, and one for a 2.9 pulley to rev to 6000 and higher shift points for when the gloves come off. It's so easy to switch a pulley, why have just one setup?
    As mentioned previously, for all the extra work involved, you are talking about more time spent tuning.
    The boost limiter idea using a V1/V2 on a 360 is not practical or effective, I will not be tuning this setup. Best of luck to you.
    Last edited by FlyinRyan; 01-24-2015 at 06:49 PM.
    Always outmanned...Never outgunned

  22. #47
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Quote Originally Posted by FlyinRyan View Post
    I will get right to the point- there is nothing to be gained from overspinning (regardless of blower rpm) a blower of this size, on an engine of this displacement. Not when you can bridge the gap by maximizing belt wrap, minimizing belt slip, and maximizing airflow in the form of intake manifold, and TB, etc etc.
    I'm not sure what you're saying here. I have no intention of driving the impeller above its designed maximum of 50k. If by overspinning you mean driving the impeller above the desired boost level, then yes- that's what I intend to do.

    Quote Originally Posted by FlyinRyan View Post
    I'll trust Tial or even the Ching Chong equivalent before relying on McMaster Carr for boost control.
    I will not use the McMaster pressure relief valve. I think it's too small to do the job. 928 Motorsports sells one that is specifically made for the exact purpose I was looking for. I will either buy theirs or make my own. Although a wastegate also relieves pressure, the boost limiter valve does not need the complexity.

    Quote Originally Posted by FlyinRyan View Post
    Fact of the matter is that a centri SC still makes power to 6k on a stock long block. I went through my notes and tune repository and found a Vortech'd Ram I did. Headers, exhaust, M1, and a V2. I shifted it at 5400 due to valve float on stock valve springs, but the rest of the configuration could sustain 6000 rpms.
    Are you saying that because of SC boost the heads can flow better at higher RPM than NA? Still like you said, valve float becomes a problem.
    Regardless of whether it's possible for stock heads to run to 6k, that's simply not what I want to do at this time. I'd rather have a nice conservative 5100 shift point. Maybe in a couple years I'll get bored and decide to take it to the next level.

    Quote Originally Posted by FlyinRyan View Post
    What limitations are you talking about?
    Air flow and valve float. Once I get my M1 4bbl on (you convinced me on that one), the heads will be the limiting factor on air flow.

    Quote Originally Posted by FlyinRyan View Post
    As mentioned previously, for all the extra work involved, you are talking about more time spent tuning.
    The boost limiter idea using a V1/V2 on a 360 is not practical or effective, I will not be tuning this setup. Best of luck to you.
    Paying to play is part of the game. Every tuner I know of has a flat rate, but charges extra in case of significant mechanical changes. I wouldn't expect it any other way.
    Sorry to hear you're not interested in trying this. One way or another I'll get it done, and I'll dyno with and without, and post the torque curves here for comparison.

  23. #48
    SCT Tuning Guru
    Join Date
    Apr 2013
    Posts
    150
    Rep Power
    2226
    Some data:

    Eddie's setup without a limiter makes 13 psi at 5300+ rpm with 2.7" and 7" pullies.
    With ambient temps around 40-50 F, manifold temps are at 220+F.
    In my experience, this translates into about 160-180 temps in the discharge piping.
    His setup heat soaks to the point where I need to pull timing after a single pass to prevent detonation.
    Last edited by FlyinRyan; 02-21-2015 at 04:32 PM.
    Always outmanned...Never outgunned

  24. #49
    Member
    Join Date
    Nov 2014
    Location
    Seattle
    Posts
    686
    Rep Power
    41
    Ryan- thanks for posting Eddie's heat data here.

    My plan is to also run a 2.7. Although the 2.5 would not over-rev with 5100 shifts, I'd rather be a little conservative about it.

    Blowing off excess pressure with the boost limiter alone would reduce the manifold temp significantly, plus I'm going overkill on my intercooler setup. With these combined, I really doubt timing will have to be pulled due to heat in my motor.

    I also read a few articles about quench, and as you mentioned it seems a good idea to use a thinner head gasket to increase the quench. (You said it was to keep quench to a minimum, but I think you misspoke). I'll probably install half-height gaskets when I install my intake manifold and RR's.


    Just had a thought- I'm wondering if I should put the limiter valve downstream of the intercooler since heat exchangers are more efficient with greater temp differentials. Relieving the pressure after the intercooler would mean higher temp in the cooler and higher heat exchange, and the energy released by pressure reduction is constant regardless of temp, so I think the manifold temp would be lower with the valve downstream of the intercooler.

    I realize blow-off valves are usually installed before the intercooler, but they aren't usually active when you're still making power, so not subject to the same heat concerns.

  25. #50
    SCT Tuning Guru
    Join Date
    Apr 2013
    Posts
    150
    Rep Power
    2226
    Quote Originally Posted by carlmon View Post
    Ryan- thanks for posting Eddie's heat data here.

    My plan is to also run a 2.7. Although the 2.5 would not over-rev with 5100 shifts, I'd rather be a little conservative about it.

    Blowing off excess pressure with the boost limiter alone would reduce the manifold temp significantly, plus I'm going overkill on my intercooler setup. With these combined, I really doubt timing will have to be pulled due to heat in my motor.

    I also read a few articles about quench, and as you mentioned it seems a good idea to use a thinner head gasket to increase the quench. (You said it was to keep quench to a minimum, but I think you misspoke). I'll probably install half-height gaskets when I install my intake manifold and RR's.


    Just had a thought- I'm wondering if I should put the limiter valve downstream of the intercooler since heat exchangers are more efficient with greater temp differentials. Relieving the pressure after the intercooler would mean higher temp in the cooler and higher heat exchange, and the energy released by pressure reduction is constant regardless of temp, so I think the manifold temp would be lower with the valve downstream of the intercooler.

    I realize blow-off valves are usually installed before the intercooler, but they aren't usually active when you're still making power, so not subject to the same heat concerns.
    I already have intercooled data already.....
    Always outmanned...Never outgunned

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •