read on oliver scholz's site that 1.6 ratio rockers are good for a 10% gain all throughout the rpm range- i think it would cost something like 30 dollars for a full set of new rockers for the car- if so, wouldn't this be one of the best bang for the buck mods? any input on this? according to his site its easy to do (especially since i already know how to go in and tighten the rockers) and listed no problems- the only things i worry about are how it effects emissions testing, and clearance inside (thought i heard that somewhere before) any ideas?

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Do you have a 4-cyl or V6? I don'y know about Emissions but I do know that BBC 1.7 & 1.6 ratio roller rockers will fit o a Duke So If you (or anyone else) wants to drop $75-100 for a set of 1.7 roller rockers I'll split a set with ya I can only get 16 at a time (same goes for the studs)

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Black 88 Coupe: 120 MPH spedo, Aux. gauge pod, 195/55VR14 Potenza RE-71 tires, GT exhaust & ground F/X Soon to have 16" White Beretta GTZ W/ 215/45ZR16's
Tom's Page

I have put 1.6 roller tips on my 3.4 pushrod that is going into my project car. I have also put a +1 cam into my daily driver 86SE V6 and just got it smogged here in CA last month without a problem. The 1.6 rockers will not affect your smog unless your calalytic convertor is borderline.

Will Small Block Chevy rockers fit a v6? LT1? LS1? or are they a unique animal?

the 1.6 ratio, are those just rockers off of a 350?

MR2KLR.... I'll go halves with you. I'm going to email you now to get some more information...

Before using 1.6 ratio rocker arms, using the cam specifications, determine the amount of valve lift. Too much lift is bad, and you don't want coil binding. If you are using a stock cam, it is probably okay, but checking won't hurt.

Just a few things to think about...

SBC rockers are 1.5:1

To calculate valve lift, take the cam lift x the rocker arm ratio.

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Timothy E. Smith
1986 SE V6 BACK ON THE ROAD AGAIN!!!!
1984 Coupe
1996 Ford Probe GT
1999 Chevrolet Silverado Z71
1975 Chevrolet ElCamino SS

According to folks that have done it...
Comp Cams and Crane both sell 1.6 rockers for the 2.8. Comp Cams is waayyy cheaper.
You should also replace the springs. I'm not sure if the coils will bind or not, but the stock springs have been on there for at least 14 years, and are getting very tired. The won't handle the increased lift very gracefully.

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Raydar

From the Department of Redundancy Department.

I have put 1.6 ratio roller rockers on several motors. I have noticed small gains in performance. The bad part on is that it changes the geometry of the valve train parts and could cause excassive wear in certain areas.

I put a performance cam on my V6 and have had no problems passing smog in CA. I doubt that 1.6 rockers would affect your smog results if you cat is in decent shape.

I thought that the L4 came with 1.75:1 rockers. Goint to 1.7:1 would reduce valve lift and breathing if this is the case.

Where do you get these 1.6 rockers? I've been looking for a set for my 2.8. Thanks.

Phil

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GTDude
25 years GM experience

1.6 rockers do change the geometry of your valvetrain but it's to such a small degree that it won't cause and excessive wear. You would have to jump to a 1.7 to start worrying about that. That is on the V6 anyway. Going one size up in rocker ratio won't affect it enough to cause problems is what i'm trying to say. (the V6 has 1.5's stock)
You can not use a small block Chevy's rocker arms on the V6 becasue the 60 degree V6 has a special 10mm rocker stud.
Comp. Cams sells roller tipped rockers in both 1.52 and 1.6 ratios for the V6. These are much cheaper than the crane full roller rockers. Crane offers their full roller rockers in both 1.5 and 1.6 but you will pay a lot more for a full roller rocker than you will a rocker with a roller tip.
The valve spring issue is one that i've heard both will and will not work. I think this is because, as already stated above, that these cars are getting up there in years and the components are worn, so it would be a good idea to replace your springs with matching ones from whichever rocker arm
manufacturer that you get them from. www.compcams.com or www.cranecams.com

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Dave Gunsul
Activities Director
Northern IL. Fiero Enthusiasts
86 GT modified
85 SE daily driver

quote Originally posted by GTDude: Where do you get these 1.6 rockers? I've been looking for a set for my 2.8.

Comp Cams Roller Tip Rockers

1.52 1413-12
1.6 1414-12

Summit, Jegs, Car Quest, Autozone, and the a local performance shop are places I checked for prices.

Note, if I had plenty of money, I'd would probably have gone the full mile and installed a set of full roller rockers.

Also, the documentation with the Comp Cams rocker arms indicates they are packaged with metric lock nuts and pivots for 2.8L V6 engines. Comp Cams help line, 800-999-0853.

Dave you are right. The L4 rocker ration is 1.75:1. I read somewhere that going to a smaller ratio incresses low end torque. I have a set of 8 full roller rockers (from e-Bay) on the way to me. They are 1.7:1 ratio for a BBC. I'll let the Forum know how they work out.

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Peace and Happiness
Frank and his fotoflash, an '84 SE
Member NIFE

I had a set of 1.6's that i pulled from my
1974 impala 350 when i swapped cams a couple of years ago. the rockers had about 5k miles
of "hard" use in that motor. one day that I
was extremely bored i put them in my 2.8
(117k miles) I noticed a performance gain,
the motor revs up quicker and my exhaust was a little louder. I haven't noticed any problems due to the rockers or coil bind.
so far I've put about 1500 miles since the rocker swap and they haven't been easy miles
(heavy right foot)all of those miles have been in town driving too. sorry for the long post

fotofrank, please be sure to share the results. I'm very interested in the outcome.

All v-6 cams can handle the 1.6 ratio . My cam w/ 424/454 lift will be close to spring bind with the 1.6 roller tip rockers . That's why I'm using the comp cams 1.52 roller tip rockers . Rock On !!!