1.7 rocker valve spring compression & clearance questions.

GT Dan · 07-15-2002

I've done a search on this website and read several posts on 1.7 rockers but still have some questions for my application.

1. I have 95 GT convertible 5.0, CAI, pulleys, installing a GT 40 intake and 24 lb injectors and the rest is pretty much stock. I'm looking at putting in 1.7 rockers and am concerned about valve spring compression and clearance. From what I've read valve to piston clearance should be fine, but will my springs hold up with 93k miles?

2. If I later get some Twisted Wedge heads and a E303 cam, leaving everything else the same, will I have valve/piston clearance problems? Also, the TW heads rate at 540 max lift on the springs and the 1.7's would give me 529; is this cutting it to close? Also, will I have any problems passing smog in CA with these combos?

Thanks,
Dan

Vortex · 07-15-2002

the rockers will put more pressure on your springs.. while it should hold, i wouldnt run it too long like that... i would change them.. but if you're going to change the heads soon, do it all at once.
With the TW heads I and they recommend you use their cam as well, They are already matched to their set. I used to think if you got the best one of every part that youd get better performance..but they work best as a set. 1.72's work on most stock engines, but with TW heads and cam, they recommend 1.6's... no real loss there.. you're still gaining horsepower by not having the friction.. Roller rockers are the way to go...

Jarrett · 07-15-2002

I agree with Adam, hold out for the 1.6's and get the TW cam when you get their heads. Matched sets are the way to go to improve reliability and driveability.

GT Dan · 07-16-2002

It might be a while (year?) before I can get the aluminum heads. In the meantime I have the intake and injectors and will get a better MAF and exhaust. How long could I run some 1.7's with my current setup?

Vortex · 07-16-2002

it should take the 1.7's just fine... so if you want to pull the valve cover twice thats cool... just dont exceed manufactuers warnings...they know best.

GT Dan · 07-17-2002

Thanks guys. I think I will get and go with some 1.7's now and then get some 1.6's with the TW heads and dump the 1.7's later. It will give me more lift at the valve and a little more performance now with the intake and soon to be exhaust mods.

I talked to the TW tech support and 1.6's were definately the way to go for my application and they do have a very nifty cam that matches up great with the heads, is smog legal and even seems to have higher flowing numbers than the E303 cam. The tech support guy said that the only difference in the Street Heat heads and the Track Heat heads were stronger springs and threads for accessories and that the castings were the same.

Vortex · 07-17-2002

why dump the 1.7's? why not go with the 1.6's to begin with. if you're going in 2wice, just use 1.6's you'll notice quite a bit of gain from the non-friction factury ones, but you wont really feel anything from 1.6 to 1.7.. Unless you got the money to do this. anywhere from $200-$300 if you havent priced em... If you do have this money, get the 1.6's and give me the money for the 1.7's... lol

GT Dan · 07-17-2002

sure.....where do I send the money?

Vortex · 07-17-2002

c/o Adam Carlin, Ocala FL 34471

fvpnt0pony92 · 07-17-2002

just get the 1.6's now and dont waste money like this. why get the 1.7's when yer just going to get the others later????!!!! WHY??!! theres not much if anything that you would gain from going with the 1.7's over the 1.6's......