TXNC5

I have a moderate cam currently, 224/228 .533/.535, with GTP Stage II heads, etc. I was told the 1.8's are worth 32/1000'ths lift, so that would make my cam .565/.567? Is this good/bad thing to do? What concerns should I have? Can I just change the rockers, or do I need new springs, etc. as well?

I was also told the rockers will work with the stock valve covers, and that they were worth upto 18hp?

Thanks.

Jadeeglide1550

You are right in the correct range for the 1.8's still to be useable. Not only will you pick up the extra lift... but you pick up a little more duration out of the cam when looking at the .050 lift specs, since the valves will open .050 a bit sooner and close to .050 a bit later. I have heard that with the 1.8's you have to grind out the support areas near the bolts for clearance... I was lucky as there was no interference with my covers, but I was working off of the stock LS1 cam, in your case it may be different. If you go the route of the 1.8's, make sure you check that they are not hitting the valve covers... checking the cover with out the gasket installed is a good way to test, just use two or three of the hold down bolts that are not even close to being tightened down, and pull the engine over by hand with a ratchet and a 15/16" socket. In my case, I used the crane kit which comes with shorter push rods... also something to think about if you are using stock length pushrods...

logan

well, yes, and no. you might have to worry about spring bind. it'll turn out to be about .561/.563 lift... however, i'm pretty sure you might not have a problem, but when we do heads we usually make sure that the springs will have optimum closed psi and achieve a maximum psi usually very close to bind at your cams standard lift.

oh yea, are webpage is updated. www.gtp-racing.com

NO CATZZ

iTrader: (10)

Just did mine this weekend. For clearance issues if you have the 97-98 perimeter bolt style covers you will need to clearance around the bosses on the tob side of the cover(closest to the manifold). The next thing, I discovered while I was doing the lash procedure 3 of my rockers bottomed out on the stud. Very bad, so I only put half of the recommended preload and relashed them after I ran it for a while. I have a about 150 miles on them and my new cam so far and they will need one more adjustment and then everything should be good.

NO CATZZ

iTrader: (10)

One more thing. Since our cars come with 1.7's from the factory you can figure your new total lift as follows.

Old lift/1.7=cam lift
Cam lift*1.8=new total lift

Example: My cam was advertised at 525/532 lift with 1.7's.
So...525/1.7=308.82 308.82*1.8=555
532/1.7=312.94 312.94*1.8=563