Supra Forums banner

1 - 5 of 5 Posts

·
Banned
Joined
·
2,385 Posts
Discussion Starter #1 (Edited)
Hey guys im just curious to get a ballpark figure on something. I'd use the search but ...you know what i mean...lol
First question though, how much can you rev crower springs and tit retainers to?
Next, how thick is a stock gasket?
Also how big of a lift can you go on a GTE before the motor becomes an interference motor? I remember some saying you can still be fine on 272's.

Now if you have a head with 1mm OS valves and took 5thou off.
Using 20over pistons stock comp 8.5:1 and 272 cams with a 10mm lift.
What would the final compression of the motor be roughly? Not sure if there is a formula or something you can use.
Would it be intereference?
Thanks Ryan
 

·
Administrator
Joined
·
4,972 Posts
Not my area of expertise, but if you use 8.5 pistons and don't need to take much material off the head or block, your compression ratio should be relatively stock. If you're going to use oversized valves, you'll need pistons with valve reliefs.
 

·
Premium Member
Joined
·
1,038 Posts
ok this is a trick question you have to understand. When your 1mm valves were installed how deep were the seats cut? And are the seats still factory?

When a valve is cut into the head deeper it changes it's throw into the cylinder naturally. Generally a +1mm valve and 272 or 282 cams are in fact interference. Just slightly so when cold and alot more so when hot and the valves have grown a bit.

Also was your block ever decked or only your head? What kind of headwork was performed as well?

Again this is a trick question to answer as there are alot of variables.
 

·
Banned
Joined
·
28 Posts
stock headgasket seems to work fine on full built cars. dont see why it wouldnt work out. and you only need to worry about your motor becoming interfearance when you break timing belts. interfearance motors run fine. they just bend valves when the timing belt breaks or skips. just stay up to date on your tbelt and you will be fine.
 
1 - 5 of 5 Posts
Top