Ive got a stock SR that needs a top end rebuild asap. Ive got all the parts except a headgasket and arp headstuds.
Bings got a cometic 88mm stock thickness HG for a good price but is that safe to run? Or what bore/thickness/brand should i be looking at if i go to JRP. I dont have any huge plans for boosting. Thanks in advance
88 mm stock headgasket? are you sure? thats fucking HUGE!!!
devon,
88mm is not “fucking HUGE!!!” im not sure what maxgohan is talking about
typical stock replacment is 87mm or 88mm and ~1.1mm thickness.
apexi makes a really nice headgasket which is what most serious busines people go for - some people have great luck with cometic, which I seem to remember bing saying a while back he has had good luck and hes making around 300whp i think.
just MAKE SURE IT’S INSTALLED PROPERLY, it wouldnt hurt to have a professional machine shop have at it also to make sure the surfaces are mintsauce.
i’m a huge noob when it comes to SR’s so please don’t take anything I’ve just said as gospel but I’m fairly confident in it.
yeah i for the apexi one as well
also i always wanted to know whats the best way you guys remove the old headgasket, from the ones i’ve changed in my life it tends to stick to the block rather than the head, and when u peal it off, sometimes it comes off clean and sometimes it brakes away and leaves residue on the block, how do you guys go about that ? is there a special technique for perfect removal ?
yes we have sold and used both cometic and apexi. they are both really good cant remember witch one is more expensive but i can check. if you use the comatic make sure u use spray head gasket sealer, bonds much better.
My motor guy said just scrape it off with a metal drywall tool and then take a sanding block to the head.
I went to JRP and picked up a cometic HG 88.5mm and 0.040 mls w/both add oil holes…which ever that means. Luckily the sr specialist was there to pick out the one for me.
how much was it? that is the one i have in stock.
i’ve heard some people say they have had bad luck with Cometics, H was telling me that a couple weeks ago. I have only used Cometics and never had an issue.
The headgasket was 107 after tax. Now the fun starts…
Take photos as you do the headgasket job, Im sure alot of people want to know exactly what you have to do in order to change the SR headgasket, would be a cool write up for the FAQ later as well.
I did start taking pics as i was going along. I had to tear the motor apart again after putting it all together because my timing chain snapped and a 10mm socket with teeth marks magicly appeared in my oil pan. Kudos to who managed to not tell me about dropping it, oh well whats done is done.
What worries me is i found a decent amount of coolant in the head before i took it off and a bit in the oil. The motor never ran, i simply cranked it for maybe a combined 35seconds added all the times i was trying to troubleshoot compression test, test spark. I hope it may just be from me cleaning the block and coolant spraying everywhere when i used the air blower and it got in the oil passageways the 1st time i cleaned the motor. Atleast i hope before i re-assemble this all backtogether that this is the case and not my cometic failing before the motor has even started. I cranked the arp headbolts 20pounds at a time in the order the FSM says right up to 70, and then tightened a tad more after a hour or so to make sure they stayed at 70. ARP says do not follow the manufactors torque specs. They say 70 using assembly lube.
I just want to hear from you guys how successfull you have been with cometic’s.
Cometic’s are a shot in the dark and generally not worth the gamble. If you don’t want to go crazy on the boost or high HP just go get an OEM replacement. It is by far the most reliable choice. Unless you need something stronger then go with Apexi or Tomei.
Also for the final head torque you should wait 24 hours to be safe.
It is also a good idea to have the head checked to make sure its true (flat) by a machine shop if the motor has any suspicion of being beat on.
Any finally make sure you have the correct ARP head studs. I have heard so this is by no means gospel that one of the holes in the block is a tad shorter then the rest on some blocks and that this can cause a problem if you are using VW head bolts which are VERY often sold as SR head bolts because they are very similar except a minuet difference in length. Best way to ensure this is a non issue is to torque the bolts with a degree wench as opposed to a force wrench. Again this isn’t gospel and feel free to disregard it as babble is you so see fit.
A quick search on FA will produce lots of experiences with head gasket issues if your curios about what people have experienced out their.
Good Luck… Double check the oil pan. 