Thicker HG theory Please Read

[Blackangusinc]

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[Blackangusinc]

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[Blackangusinc]

Are there specs listed for total cylinder volume? I'm trying to find specs for calculating the change in compression ratio when using a thicker head gasket of x thickness. Obviously it's easy to find displacement.

[matt]

Comparing anything to the 335 doesn't really work. GDI is pretty much the shit.

[nando]

For most builds on e30s the headgasket is just a band aid for lack of tunning or crap gas. if a 335I can run 10:1 then 9:1 ain't shit. The evo guys run low compression so they can run 30+ psi and make 300whp. But pulling timing till its stops knocking is the way to go I guess.

30 psi for 300whp? I hope you mean 700-800whp.. lol

[LowR3V'in]

DSM tuning =
40psi,
8.5afr,
1* timing.

[einstein57]

For most builds on e30s the headgasket is just a band aid for lack of tunning or crap gas. if a 335I can run 10:1 then 9:1 ain't shit. The evo guys run low compression so they can run 30+ psi and make 300whp. But pulling timing till its stops knocking is the way to go I guess.

[LowR3V'in]

Using thicker HG will lower the compresssion of the engine, but if you lower your stock compression, your motor will obviously be underpowered until you can reach boost. So your underpowered from say idle-4K rpm

No it won't. You're overthinking it.
Even if you're not actually making boost it'll be much faster then if it was stock.

[Blackangusinc]

Thread resurrection baby!

Has anyone boosted a stock M52TU with a stock head gasket? Results? Specs? Vanos maps? I have a build in progress and would love feedback from someone who has done it before.

[blueapplesoda]

Thread revival much?

[1990e30coupe]

There is an upside to using the stock headgasket - if you have tuning problems or have detonation for some other reason, be glad that you only have to replace the headgasket and not pistons and piston rings, or worse, as the pressure has to go somewhere. There is really no point in a ticker headgasket when stock works.

[ForcedFirebird]

I'm almost finished with a 11.56:1SCR twin turbo motor, and am planning on running pump gas. It all depends on the cam and head efficiency.

Check out theoldone.

[88driftIS]

Well I am another ex honda guy, I had a 95 civic with the 1.6 single cam v-tec. I had 8-1 pistons and a thicker head gasket. I ran it on 10-12 psi. My car would stay door to door with a buddy of mines 93 with the same set up but stock motor. It doesn't make that much of a difference(not saying there is no difference). It's all in the tune. Having lower compression just makes it safer. And for the guy that said that lower compression causes more detonation. Your kidding right? If that is the case why isn't everyone using insane high cr with boost. Maybe I should go 13-1 and through 15 psi through my m20...

[So Live]

And I know cardcounter on bimmerforums made 600-640whp something in that range with a stock m52 with studs and .140 gasket. I dunnooo. :-?

Make that 704whp before it failed.

Stock m52 for him was a stock block. He added the .140 (twice as thick as stock) MLS and the ARP head studs, head work and all kinds of bolt ons.

None the less, 704 whp out of a bottom end that was made to produce about 160-170 whp from the factory.

MLS seems to be working for our bimmer motors. I know a few people are making upwards of 450-550whp on US s50's with a MLS and studs. Its a proven recipe for kick ass power.

I think the gains in mid to top end greatly out weight the minimal loss from the drop in CR on the bottom end. From what i hear, most people can hardly tell the difference just driving around normally.

[devonjordan]

3 steps back + 5 steps forward = 2 steps forward. Makes sense to me.