Hey everyone, I know this is my first post but Ive been a lurker for a while and have done quite a bit of searching. I just bought an 87 turbo off of my roomate with a bhg. I bought everything for the repair and its at the shop. I ended up with the stock thickness HKS mgh. Now Im seeing everyone say that you have to get the block decked for the mhg to seal right. Is this 100% necessary? How many people here didnt pull the block to be resurfaced when installing a mhg?
Another MHG thread!
- Thread starter dwhite
- Start date
Thanks for the quick reply. Damn I really dont know if I can afford to do that right now. I know lapping the block while its still in the car isnt ideal but can I get it to a passable spec by doing it that way? Forgot to mention I'll be using arp studs too.
just wait till you can deck it!! if you dont do it right, you will just have to spend more money when you have to do it all over again when it blows... idk about the lapping while its still in, but it sounds like a short cut. And ive been learning that, thats not a good idea with these motors.
if you cant do it now, maybe just use a stock type HG. IDK i just wouldnt out a MHG without decking the block and head.
if you cant do it now, maybe just use a stock type HG. IDK i just wouldnt out a MHG without decking the block and head.
Ive been in a rental car for a month now. I work for herts so its not super expensive but its draining my account. I guess for now im probably gonna have to go with a stock hg. My future plans for the car I only really want high 3 to 400 to the wheels. Whats a stock hg good for with studs? The thing that gets me is that in volvo land where im coming from ive never heard of prepping the block for an mhg. Then again theres guys running 600+ on stock ones.
A stock HG torqued down with ARP studs should be daily driven reliable for 300-400, just depending on tune,condition of engine,how you drive, ect
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I am one that's rolling the dice. I've been running an HKS MHG w/ARP Studs with a machined head; but, on an "unmachined" block. That said, my block surface was flat and cleaned up exceptionally well.
If you're not ready for big power, just run the OEM with ARP's. That's a great combination!
An OEM HG will only hold what the tune will allow. In some cases, it's a lot!
Really!?
If you're not ready for big power, just run the OEM with ARP's. That's a great combination!
An OEM HG will only hold what the tune will allow. In some cases, it's a lot!
ask92;1691481 said:
Really!?
Hey kenny,
I'm currently leaning toward using a stock Toyota HG with arp's on my car. I never installed arp's in the first place, so I'm assuming that's why the HG blew..(duh.) I'm running a 57 trim ct26 at about 10psi. Would you say that's too much power/boost for the stock gasket/ arp combo?
I've never hit fuel cut with this setup, and don't plan on shimming the wastegate.. so I should be around 300 wheel, right? (running stock elbow, 3" DP, 2.5" exhaust, 2.5" hardpipes, Ebay intercooler, apexi intake)
Thanks!
Aaron
I'm currently leaning toward using a stock Toyota HG with arp's on my car. I never installed arp's in the first place, so I'm assuming that's why the HG blew..(duh.) I'm running a 57 trim ct26 at about 10psi. Would you say that's too much power/boost for the stock gasket/ arp combo?
I've never hit fuel cut with this setup, and don't plan on shimming the wastegate.. so I should be around 300 wheel, right? (running stock elbow, 3" DP, 2.5" exhaust, 2.5" hardpipes, Ebay intercooler, apexi intake)
Thanks!
Aaron
If the surface is clean and warped no more than 1 thou then there's no need to surface it.. Check it with a straight edge and a feeler gauge. Stock composite head gasket with proper torque will be good for 500+ depending on the tune..
---------- Post added at 09:38 PM ---------- Previous post was at 09:37 PM ----------
I just made 303WHP 352ft lbs of torque on 13lbs with a stock CT 26.. ARP head bolts torqued down per spec and a Felpro head gasket.. Block surface was cleaned and checked for straightness, head was machined and has been fine..
---------- Post added at 09:38 PM ---------- Previous post was at 09:37 PM ----------
I just made 303WHP 352ft lbs of torque on 13lbs with a stock CT 26.. ARP head bolts torqued down per spec and a Felpro head gasket.. Block surface was cleaned and checked for straightness, head was machined and has been fine..
zambini;1691556 said:
You should be fine with that HG/ARP Combo at 10 psi. Given that nothing else is wrong...
You're not going see 300 WHP with those mods at stock pressure. Likely not at 10 psi either. You're on your way though!
ask92;1691576 said:I edited it so even you could understand
Thanks. I didn't mean to sound like a turd; but, when someone posts mis-information in the Tech Section, it should be corrected. Don't worry...we've all done it.
aksing this in multiple places:
if i have the head machined for flatness, doesnt that mean that the stock gasket will be too thin in order to maintain a safe compression ratio? and do they make thicker composite gaskets to make up for lost head material?
Thanks,
Aaron
if i have the head machined for flatness, doesnt that mean that the stock gasket will be too thin in order to maintain a safe compression ratio? and do they make thicker composite gaskets to make up for lost head material?
Thanks,
Aaron
5 or 6 thou really isnt going to be a problem, I am running N/A pistons with 10 thou taken off the head on a stock composite head gasket and thats where I am seeing detonation now, however im probably at about 9.4:1
no no no, i completely understand where your coming fromCajunKenny;1691671 said:Thanks. I didn't mean to sound like a turd; but, when someone posts mis-information in the Tech Section, it should be corrected. Don't worry...we've all done it.
If your going to machine the block it would be worth it IMO to just do the head and go mhg, even if your not upgrading and looking for HP numbers its just for good peace of mind.zambini;1691704 said:
zambini;1691704 said:
dwhite;1691708 said:
Higher compression = lower detonation point = lower boost limit
Lower compression = higher detonation point = higher boost limit
Every engine is different and one person's results won't equal another's...
There's a guy on here running a 9.4 CR. At ~7 psi, his setup starts knocking any leaner than 10.5. However, at that ~7 psi he put down close to 280 whp.
All that said...standard machining to a head will work fine with an OEM HG.
Im running a Federal Mogul HG with .5MM missing from the block. 3500 miles on the rebuild so far & no problems & i didn't get anything machined.