hey guys, i was wondering if any of you have installed (or know about installing) 1.6 roller rockers on any of your IROCs. if so, any suggestions? any fit problems? and what kind of power increase?

 

I have an 87 IROC 305TPI 5-speed, edelbrock TES headers, and all the little TPI tricks and bolt-ons......if this helps at all!

 

I have read in other posts that you may run the risk of pulling the rocker studs out due to the increased pressure at high RPM. I would wait until you replace the stock heads with a set that has screw-in studs.
If you do put them on, and you don't rev up the engine real high then you might be alright.

 

Full roller or just roller tipped?? I installed 1.6:1 roller tipped rockers in mine and have wound it up to 5500 with no problems, and believe me, I asked around on here before I bought them. Full roller might be a different story though, I know you'll probably have to get taller valve covers, and then you'd be talking about the screw in studs.

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Kevin Irving
85 Trans Am WS-6, 305 TPI, custom burned '86 PROM with '87 "165"ECM, Accel Supercoil & 8.8 Wires, Rapidfire #2 @ .055", MSD 6AL, 1.6:1 Roller tipped rockers, Homemade AFPR, K&N cone, no airbox, Aluminum Driveshaft, Wonderbar, TB Coolant Bypass, Ported Plenum, Descreened MAF, Syclone Fuel Pump, JET Airfoil, Mobil 1 synth in all but transmission.

15.556 @ 86.65mph, Nov 10, 2000.... I know it sucks.. but it will get better!

http://www.geocities.com/transam85tpi/

Member - The Tidewater Trans Am Club, Norfolk VA http://www.geocities.com/ttacva/

 

Switching from 1.5 to 1.6 rockers won't do a whole lot for your car IMO. I mean, it will help, but its not worth the $200 that a set of 16 slef aligning roller rockers costs.

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End with 2.77:1 Gears.

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Performance Resource Chip, Accel Ignition Coil, Cap, Rotor, 8.8mm Wires, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

Soon to Come: 7.625" 10 Bolt with 3.42s and Accel TPI Intake Base

 

you dont need to change valve covers to go with 1.6 rockers. I got crane gold full roller on my car. Dont know how much they help though. But hey they couldnt hurt.

 

did any of u guys using them, run into any problems with the pushruds rubbing at all in the head? i just got my 1.6 magnums yesterday and i wondered if they fit with no problems...on stock L98 heads.

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white/gold GTA ,leather 5.7TPI 700r4 3:27posi twin cats,3"catback,aluminum d.shaft ported plennum,afpr,8mmwires,k&Nand all other "free" mods, performance resource chip,SLP cold air intake.

 

They should fit fine. i havent heard of any fittament problems. If your gona run full roller rockers, run the Harland and Sharp's. They are the best you can buy. Cost less then the Cranes and are just as good (probably better) then the Crane's. Plus Top Fuelers run Harland and Sharp, so if its good enough for 7,000hp, then isnt it good enough for your car?

 

Eddie89T/A I have the crane 1:6 full roller rockers on my car with no problems. My heads have the little slots for the pushrods and the pushrods do come close but there is clearence. You should pick up about 30 thousands in lift from a 1:5 ratio but the real advantage is the roller fulcrum compared to the stamp steel stock rockers. I did have to remove the exhaust valve rotators and shim the exhaust springs. You might not have to do that with your rockers.

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SLP 1 5/8 Headers,ATR catback exhaust,SLP cold air box,Crane 1:6 roller rockers,Bosch plugs and MSD wires,MSD Coil,Fastchip,Borg Warner 9 bolt 3:27,Corvette Servo,ROH ZS 17X9.5 Goodyear GSC,s 275/40/17

 

why did u have to shim them? and um what r the exhaust valve rotaters? did the pushrod rub the head???

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white/gold GTA ,leather 5.7TPI 700r4 3:27posi twin cats,3"catback,aluminum d.shaft ported plennum,afpr,8mmwires,k&Nand all other "free" mods, performance resource chip,SLP cold air intake.

 

I have the Comp Cams Magnum 1.6 roller tip rockers on my IROC. I did not have and have not had any problems installing them or operting them. The clearances on them are fine, and the rockers fit fine under stock valve covers. If you get roller tipped, make sure they are self aligning though.

They made a small difference in my car. Like I always say, a little here and a little there starts to add up! I have not had any problems pushing the car either. It goes to 5500-6000 without any problems.

Matt

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irocet@hotmail.com

drive.to/Stang_Kilr

88 IROC-Z -- 350 L-98, 700R4, Flowmaster, K&N, MAF Sceens Removed, Airfoil, March Pullies, Comp Cams Magnum 1.6 Roller Rockers, Bosch Platinum Plugs, Accel 8.8 mm Wires, Hypertech Cap & Coil, Hypertech Chip, Hotchkis Strut Tower Brace, One Loud Stereo!

 

Eddie the exhaust valve rotators are suppose to help cool the exhaust valve they came stock on my car but talked to a few people at GM and they said it really did not help much. I had to remove them because on the crane self-aligning rockers they have these little dog ears or whatever on the side and they would hit the rotator the intake was no problem they did not have rotators. I had to shim springs to get the correct installed height after removing rotators. Pushrods do not hit the head.

 

thanks all.....

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white/gold GTA ,leather 5.7TPI 700r4 3:27posi twin cats,3"catback,aluminum d.shaft ported plennum,afpr,8mmwires,k&Nand all other "free" mods, performance resource chip,SLP cold air intake.