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  1. #1
    Member Mark 318 ita's Avatar
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    thinkin about 1.7 roller rockers

    Hi guys,
    i'm looking for another lil bit of performance.
    i already saw these:
    http://thespeedfreaks.net/showthread...Roller-Rockers
    http://thespeedfreaks.net/showthread...Roller-Rockers
    http://thespeedfreaks.net/showthread...s-I-NEED-INPUT!!

    one thing got me scared:
    the line when FlyingRyan said that is not good to put any valvetrain changes, 1.7s included.
    My z is running 230000km
    what do you think?
    98 ZG 318 limited: np 242 swap,dana30hp swap,aussie locker, shift kit, optima red, 170lbs reduction, 5.9 vents, kn air filter, air ram, 1.7 HS RRs, SCT 93 oct tune, magnaflow muffler 12255, magnaflow hi-flo cat, spectre air hat, 2x52mm tb, 5.9 efan swap, ngk fr5-1 plugs, mopar perf wires, new cap 'n rot, maxxperf coil, iat relocation, roof lights, pirelli scorpions on masitaly 16x7 rims ET=0, ome HD coils +2",rubic exp +2"shocks, skyjacker ss, rubic exp adjustable front arms, jks rear+procomp front trackbar, prothane engine n tranny mounts, prothane sway bars bushings, drilled n slotted rotors, aeronautical front brake lines, purple led into front grill, hella h4s 100/55w, osarm h3s 55w.
    my channel
    https://www.youtube.com/TommyVercettism/videos

  2. #2
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    I was considering installing a cam, rockers, push rods and new valve springs in my 5.9. Ryan advised me not to do so without buying new heads as well. Got too expensive so I gave up the idea and will stick to just the tune and present breathing mods
    .

  3. #3
    RallyJeep GO
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    There's no reason you can't do some valvetrain mods with the stock heads. Just remember that they're somewhat limited in lift capability (can't remember the limit off-hand) and they don't flow great, so don't go crazy and expect a ton of power.
    1998 ZJ 5.9 Limited - Deep Slate
    Mods: Big trans cooler, 231 swap, Indy MA-X 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

  4. #4
    Member Mark 318 ita's Avatar
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    Hi thanks for the infos,
    so the only prblem is that with just the rr i'm not getting all the power i could get with heads mod...correct?
    thanks again
    98 ZG 318 limited: np 242 swap,dana30hp swap,aussie locker, shift kit, optima red, 170lbs reduction, 5.9 vents, kn air filter, air ram, 1.7 HS RRs, SCT 93 oct tune, magnaflow muffler 12255, magnaflow hi-flo cat, spectre air hat, 2x52mm tb, 5.9 efan swap, ngk fr5-1 plugs, mopar perf wires, new cap 'n rot, maxxperf coil, iat relocation, roof lights, pirelli scorpions on masitaly 16x7 rims ET=0, ome HD coils +2",rubic exp +2"shocks, skyjacker ss, rubic exp adjustable front arms, jks rear+procomp front trackbar, prothane engine n tranny mounts, prothane sway bars bushings, drilled n slotted rotors, aeronautical front brake lines, purple led into front grill, hella h4s 100/55w, osarm h3s 55w.
    my channel
    https://www.youtube.com/TommyVercettism/videos

  5. #5
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    The higher lift ratio of 1.7 would give the stock heads more flow at higher RPM, at the cost of some low-end torque... the problem is with the stock intake manifold you won't see any benefit, except the small decrease in friction due to the rollers. I would not do it.
    If you got a new intake and RR's, that's a different story. It's all about matching the flow of intake components (TB, Intake, heads and cam). You already have a 52 TB, so if you upgraded the intake (or at least ported the keg), 1.7 RR's would effectively increase the cam, and the heads would see faster valve rise, and increased flow with higher lift. This would be a good match, and would give you some benefit you could feel... whether it would be worth the expense depends on your long term plans. Don't do it if a cam and heads are in your future.

  6. #6
    RallyJeep GO
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    You can definitely gain some power over stock with the kegger, just not a ton. Given a mild cam or 1.7 rockers with stock heads, stock keg and a 52mm TB, you'll gain some power. But if you threw better heads on there and a better manifold, it would make more power with the same rockers and cam.
    1998 ZJ 5.9 Limited - Deep Slate
    Mods: Big trans cooler, 231 swap, Indy MA-X 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

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    Quote Originally Posted by comptiger5000 View Post
    You can definitely gain some power over stock with the kegger, just not a ton. Given a mild cam or 1.7 rockers with stock heads, stock keg and a 52mm TB, you'll gain some power. But if you threw better heads on there and a better manifold, it would make more power with the same rockers and cam.
    I don't see how you could get anything noticeable with the stock keg and RR's. Keg flows 180 max (ported about 190), stock heads flow 235, so the keg is the limiting factor. RR's only change the opening speed and total lift, not duration.
    I'd do the intake before worrying about the RR's so it can at least match the heads' flow, then any future improvements to the heads would be significant... like you said, better heads and manifold would get more improvement from the same RR's.

  8. #8
    RallyJeep GO
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    I ran a keg on my heads/cam setup for a while. It still fell off around 5000 rpm, but it definitely made a lot more power than stock. Just not as much as it did after I put the airgap on. By ditching the stock weenie cam, you can still do a better job of pulling air through the fairly restrictive keg.
    1998 ZJ 5.9 Limited - Deep Slate
    Mods: Big trans cooler, 231 swap, Indy MA-X 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

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    I believe it, but Mark's question was about RR's, and a cam can do tricks RR's can't.

  10. #10
    Member Mark 318 ita's Avatar
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    Hi guys,
    yes since i'm on a budget i was thinkin only rollers rockers,
    but seems it's not worth it...
    98 ZG 318 limited: np 242 swap,dana30hp swap,aussie locker, shift kit, optima red, 170lbs reduction, 5.9 vents, kn air filter, air ram, 1.7 HS RRs, SCT 93 oct tune, magnaflow muffler 12255, magnaflow hi-flo cat, spectre air hat, 2x52mm tb, 5.9 efan swap, ngk fr5-1 plugs, mopar perf wires, new cap 'n rot, maxxperf coil, iat relocation, roof lights, pirelli scorpions on masitaly 16x7 rims ET=0, ome HD coils +2",rubic exp +2"shocks, skyjacker ss, rubic exp adjustable front arms, jks rear+procomp front trackbar, prothane engine n tranny mounts, prothane sway bars bushings, drilled n slotted rotors, aeronautical front brake lines, purple led into front grill, hella h4s 100/55w, osarm h3s 55w.
    my channel
    https://www.youtube.com/TommyVercettism/videos

  11. #11
    im super special x10radsponge's Avatar
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    I think they were. However I also knew I was looking for an M1 intake which is supposed to compliment them.

  12. #12
    Member Mark 318 ita's Avatar
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    Quote Originally Posted by x10radsponge View Post
    I think they were. However I also knew I was looking for an M1 intake which is supposed to compliment them.

    Hi, i'm sorry, i' m not understanding,
    Do you think is worth to install the rrs without heads and intake or not?
    Thanks
    98 ZG 318 limited: np 242 swap,dana30hp swap,aussie locker, shift kit, optima red, 170lbs reduction, 5.9 vents, kn air filter, air ram, 1.7 HS RRs, SCT 93 oct tune, magnaflow muffler 12255, magnaflow hi-flo cat, spectre air hat, 2x52mm tb, 5.9 efan swap, ngk fr5-1 plugs, mopar perf wires, new cap 'n rot, maxxperf coil, iat relocation, roof lights, pirelli scorpions on masitaly 16x7 rims ET=0, ome HD coils +2",rubic exp +2"shocks, skyjacker ss, rubic exp adjustable front arms, jks rear+procomp front trackbar, prothane engine n tranny mounts, prothane sway bars bushings, drilled n slotted rotors, aeronautical front brake lines, purple led into front grill, hella h4s 100/55w, osarm h3s 55w.
    my channel
    https://www.youtube.com/TommyVercettism/videos

  13. #13
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    Stock rockers are 1.7

    Measure and see. It's a myth that they are 1.6 as well as the fact that 1.7 aftermarket rockers improve performance.

    1.6 rockers will worsen performance. No one notices because no one installs 1.6 aftermarket rockers.

    This is why 1.7 aftermarket rockers work without spring upgrades!!

    Paul

  14. #14
    RallyJeep GO
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    Uh, no. Stock rockers are definitely 1.6. They might not be exactly 1.6, but they're not 1.7. Vipers had 1.7 rockers stock, but the Magnum small blocks are 1.6. Older LA small blocks were 1.5.
    1998 ZJ 5.9 Limited - Deep Slate
    Mods: Big trans cooler, 231 swap, Indy MA-X 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

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    Well, I havn't physically measured myself. So I supposed I should shuddup. I have measured side profile photo of the stock rocker.

    Here is a blog that measures them at about 1.7:

    http://www.moparchat.com/forums/arch...p?t-67058.html

  16. #16
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    The stock rockers aren't nearly as precisely made as good aftermarket ones, so it's entirely possible some stray closer to 1.7. They're spec-ed as 1.6 according to Chrysler though, and that's what the cam companies go with as well.
    1998 ZJ 5.9 Limited - Deep Slate
    Mods: Big trans cooler, 231 swap, Indy MA-X 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

  17. #17
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    Quote Originally Posted by paulsheer View Post
    Well, I havn't physically measured myself. So I supposed I should shuddup. I have measured side profile photo of the stock rocker.

    Here is a blog that measures them at about 1.7:

    http://www.moparchat.com/forums/arch...p?t-67058.html
    Those guys measuring the rocker movement from above cracked me up. There's no way to measure it accurately like that - measuring a photo of the profile is probably more accurate! Even if you could get an accurate measurement that way, the rocker arm ratio is not a measurement of how much the valve moves relative to the push rod, but the ratio of the length differences from the center pivot to the valve contact center and to the pushrod contact center. The ratio of the movement varies throughout the stroke because the contact points are not in a straight line with the center pivot.
    What you can be sure of is a 1.7 will give higher lift and faster rise than a 1.6 on any given motor.

  18. #18
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    "... rocker arm ratio is not a measurement of how much the valve moves relative to the push rod, but the ratio of the length differences from ..."

    Is this a case of "a distinction without a difference" perhaps?

  19. #19
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    Quote Originally Posted by paulsheer View Post
    "... rocker arm ratio is not a measurement of how much the valve moves relative to the push rod, but the ratio of the length differences from ..."

    Is this a case of "a distinction without a difference" perhaps?
    No... the included angle between the three centers causes significant difference and actual relative lift from the length ratio, so you can't determine the spec ratio by measuring travel. Read about it here: http://performancetrends.com/Definit...cker-Ratio.htm

  20. #20
    Member Mark 318 ita's Avatar
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    hi guys,
    back on this,
    http://www.southeastrt.net/
    does anyone remember the last name of a guy named John working at SouthEast Perf? John...?
    thanks
    98 ZG 318 limited: np 242 swap,dana30hp swap,aussie locker, shift kit, optima red, 170lbs reduction, 5.9 vents, kn air filter, air ram, 1.7 HS RRs, SCT 93 oct tune, magnaflow muffler 12255, magnaflow hi-flo cat, spectre air hat, 2x52mm tb, 5.9 efan swap, ngk fr5-1 plugs, mopar perf wires, new cap 'n rot, maxxperf coil, iat relocation, roof lights, pirelli scorpions on masitaly 16x7 rims ET=0, ome HD coils +2",rubic exp +2"shocks, skyjacker ss, rubic exp adjustable front arms, jks rear+procomp front trackbar, prothane engine n tranny mounts, prothane sway bars bushings, drilled n slotted rotors, aeronautical front brake lines, purple led into front grill, hella h4s 100/55w, osarm h3s 55w.
    my channel
    https://www.youtube.com/TommyVercettism/videos

  21. #21
    im super special x10radsponge's Avatar
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    I am using the HS 1.7s currently. These along with the TB and M1 2bl are the best bolt on items. The rockers are not hard to install. Just remember to hang onto the pushrods. They can move into the valley. If you are doing the intake at the same time that is not an issue.

  22. #22
    Member Mark 318 ita's Avatar
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    Thanks,
    nope just the RRs for now.
    98 ZG 318 limited: np 242 swap,dana30hp swap,aussie locker, shift kit, optima red, 170lbs reduction, 5.9 vents, kn air filter, air ram, 1.7 HS RRs, SCT 93 oct tune, magnaflow muffler 12255, magnaflow hi-flo cat, spectre air hat, 2x52mm tb, 5.9 efan swap, ngk fr5-1 plugs, mopar perf wires, new cap 'n rot, maxxperf coil, iat relocation, roof lights, pirelli scorpions on masitaly 16x7 rims ET=0, ome HD coils +2",rubic exp +2"shocks, skyjacker ss, rubic exp adjustable front arms, jks rear+procomp front trackbar, prothane engine n tranny mounts, prothane sway bars bushings, drilled n slotted rotors, aeronautical front brake lines, purple led into front grill, hella h4s 100/55w, osarm h3s 55w.
    my channel
    https://www.youtube.com/TommyVercettism/videos

  23. #23
    Member Mark 318 ita's Avatar
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    just oredered 1.7 RRs and a new valve cover gasket
    hope everything is all right...
    98 ZG 318 limited: np 242 swap,dana30hp swap,aussie locker, shift kit, optima red, 170lbs reduction, 5.9 vents, kn air filter, air ram, 1.7 HS RRs, SCT 93 oct tune, magnaflow muffler 12255, magnaflow hi-flo cat, spectre air hat, 2x52mm tb, 5.9 efan swap, ngk fr5-1 plugs, mopar perf wires, new cap 'n rot, maxxperf coil, iat relocation, roof lights, pirelli scorpions on masitaly 16x7 rims ET=0, ome HD coils +2",rubic exp +2"shocks, skyjacker ss, rubic exp adjustable front arms, jks rear+procomp front trackbar, prothane engine n tranny mounts, prothane sway bars bushings, drilled n slotted rotors, aeronautical front brake lines, purple led into front grill, hella h4s 100/55w, osarm h3s 55w.
    my channel
    https://www.youtube.com/TommyVercettism/videos

  24. #24
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    Im pretty thrilled with my M1, 1.7 HS rockers, 52mm TB, DT's, full 3" exhaust and ryans tune. Certainly a very nice pickup and I see no noticeable loss of low end torque. If anything its better. I was pretty worried about that since you read about it fairly often.

    If you have any thoughts of getting an M1 I would be on the look out. Cant see the prices ever going any lower, just higher!
    1998 Jeep 5.9- Slate Black


  25. #25
    Member Mark 318 ita's Avatar
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    thanks for the tips,
    my bolt ons are similar to yours, i'm missing the M1.

    i'd really like to get one, i just don't have enough money to buy it.
    there is a guy that offered me an M1 for a nice price, seems like he can go down a little bit.

    quick question, can an M1 be transported into a luggage on a plane? how much does it weight?
    98 ZG 318 limited: np 242 swap,dana30hp swap,aussie locker, shift kit, optima red, 170lbs reduction, 5.9 vents, kn air filter, air ram, 1.7 HS RRs, SCT 93 oct tune, magnaflow muffler 12255, magnaflow hi-flo cat, spectre air hat, 2x52mm tb, 5.9 efan swap, ngk fr5-1 plugs, mopar perf wires, new cap 'n rot, maxxperf coil, iat relocation, roof lights, pirelli scorpions on masitaly 16x7 rims ET=0, ome HD coils +2",rubic exp +2"shocks, skyjacker ss, rubic exp adjustable front arms, jks rear+procomp front trackbar, prothane engine n tranny mounts, prothane sway bars bushings, drilled n slotted rotors, aeronautical front brake lines, purple led into front grill, hella h4s 100/55w, osarm h3s 55w.
    my channel
    https://www.youtube.com/TommyVercettism/videos

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