View Full Version : sr20det headgasket question
95 kouki
10-15-2011, 09:34 PM
I just dropped a valve in my blacktop sr. Im about to pull the head and see how much damage it caused. most likely it wiped out the head and cylinder. so im probably gonna just buy another swap. does it make sense to do headgasket on new motor while its out. my other motors have been stock except rocker arm stoppers ,injectors, power fc and gt2871r. The car made 327 hp on 20lbs. i eventually wanna do cams ,valvetrain,and intake manifold. I just wanna make around 400 hp to the wheels. Now here is the big question. I know when everybody does headgasket they go with same as stock or thicker. But i was thinking could i go thinner to bump up compression. that way it takes less boost to make the same power. im not talking crazy compression but something like 9 to 1 or 9.5 to 1 at the highest. just curious. i have alot of friends with boosted hondas that are starting to go even higher compression with turbos. and i know u get too high and then u only can run race gas. which is not a option premium gas only here. Thanks for any input
jr_ss
10-15-2011, 09:45 PM
It wont hurt. Even if you were to install an OEM gasket with ARP's, it would be good insurance investment. If you want 400hp, I'd suggest upgrading to a metal head gasket. Cosworth, Apexi, Greddy are all good choices.
You won't find a gasket on the market to bump your comp up to 9.0:1. I think the thinnest available headgasket is .9mm which is out of an NA SR motor. Stock SR20DET is 1.1mm thick FYI.
95 kouki
10-15-2011, 11:39 PM
Thanks for the info. Jr ss i see that u have a built s14. Do you think its worth building a motor for my hp goals. Or should i be ok with buying another blacktop.
ShadowMan
10-16-2011, 12:54 PM
I just rebuilt my blacktop sr and if 400 is what you want on the daily, then I would say upgrade your HG as well as a few other things while your that deep. I just dis a complete rebuild and after all the dumb shit and tools that I bought that I didn't have I was into it for about the same as a whole new swap. My bill from frsport was 1,500.00 and I bought oem pistons and reused my old rods. But I learned a lot while I rebuilt it. I actually just got it back together 2 days ago and fired it up. If you buy a new swap you get a tranny and full harness so there's that to think about too. If your in a hurry buy a new swap. if the car has time to sit and your patient, rebuild it.
95 kouki
10-16-2011, 01:21 PM
Thanks alot shadowman. I keep in going back and forth on a build. I know when i bought my last swap i sold all my extra parts and made half my money back. Oh well i guess i will figure it out. No rush lol. Thanks for everybodies info
fliprayzin240sx
10-16-2011, 07:43 PM
If you plan on taking the head off, make sure you mill down the oil pump front cover to match the block. Sometimes the cover mm taller than the block, causes #1 cylinder HG sealing issues when you slap on a metal HG.
jr_ss
10-16-2011, 07:53 PM
If you plan on taking the head off, make sure you mill down the oil pump front cover to match the block. Sometimes the cover mm taller than the block, causes #1 cylinder HG sealing issues when you slap on a metal HG.
Flip, I'm imagining this is a completely stock motor and shouldnt have that issue. Now if he plans on rebuilding it, then yes it is a good idea.
95 Kouki- if 400 is your max goal which it ultimately will change as you progress then id say atleast pistons. Stock rods are known to handle quite of power, just upgrade to ARP fasteners if you keep them. Honestly, depending on how much damage is done to the motor, you're best option is probably buying a new motorset.
airman
10-17-2011, 11:31 AM
If you go metal (i.e. Cometic) you'll want to have both your block and the head milled...it has to be 50RA or finer. Also you might want to use copper spray just in case. That's what I did on my KA and had no sealing problems.
Best of luck...
jr_ss
10-17-2011, 12:18 PM
Do not run a Cometic HG they are garbage.
boost addict
10-17-2011, 12:48 PM
apexi or nothing, thats what im running. as far as building the motor when i blew up my sr i contemplated buying another swap but for the price i just built it. now if i ever want to shoot for more power i'd be able to. youd put your mind as ease too knowing theres less of a chance of cracking a piston or throwin a rod. build that mofo and make some powaa :2f2f:
95 kouki
10-17-2011, 01:05 PM
I think im gonna really look into a build. Thanks to everyone for there input
ShadowMan
10-17-2011, 01:24 PM
I went thru frsport for everything, they helped out with alot. I'm running an apex by with no copper spray, so far so good. Oem for most everything else, except the valve seals they were whatever brand frsports sells. And arp studs foe rotating assembly and head. If you go with studs, take two of the main studs and shave two full threads off of each before you install. They will hit your upper oil pan later on if you don't. GLWB.
vBulletin® v3.8.11, Copyright ©2000-2021, vBulletin Solutions Inc.