Tpadden Posted February 3, 2022 Share Posted February 3, 2022 I have my stock (exhaust/mapped/autotune/hordpower air box) motor being pulled to install a undercut/micro polished transmission. Does it make sense to go ahead and install a thinner head gasket .10 ($90) will the motor is out, or any other relatively cheap mods? Don’t plan on spending big money on a full SB build since I’m still an amateur and it’s not HP that’s holding me back. Link to comment Share on other sites More sharing options...
Mt707 Posted February 3, 2022 Share Posted February 3, 2022 Does a thinner gasket do anything? I’d assume it increases compression, but at such a small rate, is that enough to make a difference? Link to comment Share on other sites More sharing options...
Tpadden Posted February 3, 2022 Author Share Posted February 3, 2022 Yeah bumps up compression is my understanding. If I can gain 1 or 2 hp for relatively cheap since my motor is already gonna be out that’d be nice. Just wondering if I can get that result or if it’s a waste my time if I don’t plan to do any other engine work at this time. Link to comment Share on other sites More sharing options...
Mt707 Posted February 3, 2022 Share Posted February 3, 2022 1 hour ago, Tpadden said: Yeah bumps up compression is my understanding. If I can gain 1 or 2 hp for relatively cheap since my motor is already gonna be out that’d be nice. Just wondering if I can get that result or if it’s a waste my time if I don’t plan to do any other engine work at this time. Imo, you’ll never notice the 1-2hp difference and it’s not worth pulling the head strictly for a new gasket if you don’t plan on doing any other work on the engine. Link to comment Share on other sites More sharing options...
M. Hausknecht Posted February 3, 2022 Share Posted February 3, 2022 I'd at least ask Gregg if, in his experience, there are any valve-to-piston contact issues with stock pistons and cams with the thin head gasket. I've been told by a very reliable source not to cut either the head or the cylinders to increase compression but i didn't ask about thinner head gaskets. One thing to be aware of is that your cam timing will be altered with the thinner head gasket (due to the shortened distance between the crank and the cams) so you'll really want to make/buy slotted cam gears and retime the cams. Since the engine is coming apart anyways, I'd at least clean up the ports and match the TB bores to the boots to the intake ports. I'd also get a 5 angle or full radius valve job. Of course, to the extent all this improves the motor's volumetric efficiency, which is the point after all, your tune will be off some. 1 Link to comment Share on other sites More sharing options...
AP996 Posted February 3, 2022 Share Posted February 3, 2022 From experience of measuring my engine I think you would be ok with valve to piston clearance if your using stock cams, I took 14 thou off my cylinder head which is about the same amount as the difference between the stock and theSpears gasket, however I’m not sure you would have enough squish clearance, this was why I had the head skimmed instead off buying the Spears gasket myself. I don’t know exactly how much this motor stretches at full revs but at a guess I’d expect at least 25 thou ( if someone knows for sure please correct me), from my measurements on my engine I didn’t think I would have enough and didn’t want to strip the bottom of the engine to machine the pistons the required amount. As stated above you should really degree in your cams if you use the thinner gasket or cut your head. 1 Link to comment Share on other sites More sharing options...
Tpadden Posted February 4, 2022 Author Share Posted February 4, 2022 (edited) I appreciate the feedback! Will just keep the engine stock mostly because I’m cheap but also think my money would be better spent on tires and track time. Edited February 4, 2022 by Tpadden 1 Link to comment Share on other sites More sharing options...
AP996 Posted February 4, 2022 Share Posted February 4, 2022 16 hours ago, Tpadden said: I appreciate the feedback! Will just keep the engine stock mostly because I’m cheap but also think my money would be better spent on tires and track time. If you wanted to do something relatively cheap, I’d get the inlet cam reprofiled with a grind that you can still use the stock springs with, instead of the engine getting breathless by 9000 rpm it will pull hard to 10000, that extra 1000 rpm would be really useful on track and let you run a lower gearing for faster acceleration. Just my thoughts though. Tires and and track time are great investments too. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now