Changing BHG. Anything else?
 

So I bought a 88 with a BHG. Me and a couple buddies are changing it and its quite an experience. My more automotive savvy friend changed his on his Ford Escort so he's a big help. We got everything off and the head is getting machined soon once I set something up. Just wondering what head gasket I should use. I was looking at the HKS stopper cause I read that its better than the bead but idk if it pays to do that. I do plan on doing more to the engine to build up horse. Suggestions for head studs or bolts would be nice. Also do u think I should replace a bunch of my other gaskets and seals while the head is off? And I saw something about replacing vacuum hoses with silicone hoses could create a better seal and help with lost horse power. Any answers are appreciated. Also if you suggest something try and post a link of where i can get good ones cause I dont wanna buy the cheap crap. Any suggestions for other things to do while the head is off are also GREATLY appreciated.

Thanks

the stopper gasket is a good choice. id get at least arp head bolts, if you can find a good deal, go for the studs, but they are a lil more involved on the install.

replacing the vac hoses with silicone is a good idea, and if you can get silicone hoses readily for a good price, go for that as well.

everything else kinda depends on your future plans for the car. hit back with some info on what your looking for and we will go from there.

ps- i picked up my arp studs and hks 1.2 mm gasket off cheebay. the silicone hosing you should be able to get at a parts store or online in rolls.

well i want to run more boost with the stock turbo first. Later i plan on getting a bigger turbo. Right now it will have no exhaust after the turbo. I also have a godspeed intercooler installed

well you could do the aforementioned upgrades, as well as an exhaust, proper CAI, 550cc injectors and lexus AFM.

or go all out and get a standalone ecu. allows more flexibility with fuel and timing and lets you squeeze the most out of your upgrades.

as for running no exhaust after the turbo...i wouldnt recommend that on a street car. at minimum put a down pipe and dump, and if you get caught with that, big no-no so i dont condone that.

as for anything else, the MHG and bolts/studs will be nice upgrades and as long as you prep your block and head right and follow proper torque procedures then that should help immensely for boost.

you could get forged pistons, but thats all up too you, the stock ones handle a good hand full of boost.

ive been reading that rod bolts are a weak point, but its kinda hit and miss with those case. either way, if your rebuilding, you can pick up the ARP bolts for about 60 bux and have the rods resized for a few bucks at the machine shop.

other than that, good flywheel/clutch combo, and its pretty much it. just follow the procedures and triple check everything, should be good.

Do not forget to take the head down to the shop for a check up. The kid that did my guy did not and there was a hairline crack in the block that drove us nutty. Good results depends by following good practices. Saving a little money by cutting corners will turn the tables and in the end cost even more money.

Head is in the shop right now getting machines, pressure tested, and a vacuum test for the valves. I think I'm going to get a kit for the silicone vacuum hoses. Comes with 3 different sizes that i need, a hose cutter, and it comes with instructions or something. I was going to go with the ARP head bolts that my friend recommended but im going to do some more research on that as well as the silicone vs regular hoses.

Machinist is taking off about .3mm off the head. I've been reading around online here and it seems like some people are running 19 psi after they took off the same amount on the head and block combined. And they also said they were using just a 1.2mm HKS stopper head gasket. I thought you were supposed to get a bigger head gasket to keep the same compression ratio? If someone could clarify that for me i would appreciate it. Also im not sure weather or not to go with ARP head studs or head bolts. Help me PLEASE! im gonna pull my hair out. :help:

And now she runs boys
 

Runs like a beauty now boys. Thanks for the help. I have a stock head gasket cause we didnt shave the block, ARP head bolts and the sent some nice stickers so i can make a shopping list on my car. New gaskets also came with the head gasket so i replaced what ever needed replacing. I'm not quite sure what to run for exhaust. what does everyone else run? 3 or 4 inch? and what metal do u suggest?

If u get silicone hoses then I would use something like zip ties at each end. I have the silicone kit and I kept getting leaks and some would blow off so I used zip ties. I would run a straight 3 inch from turbo back 4 inch is a little over kill. If u got stainless steel then it would never rust but costly.

do u have a link to the kit u bought?
Did u notice any power increase with the kit at all or is it not even worth it?

They sell a kit on eBay but I got mine from my auto parts store (pepboys) 30$ it came with 3 sizes and I just cut to fit. As for power yes I got some power back but my hoses were original so I think I had a leak.

Me and my friend didnt go with a MHG because we didnt shave the block. My question is did we make a mistake by no going with a metal one? I was reading that some ppl dont shave the block and other say that you absolutely have to get the head and block shaved. I was reading suprra_girls thread on steps to modifying your supra and i would love to do a lot of that stuff but idk if i should without a MHG. We did torque the headbolts down to 90psi though.

The stock hg is good to around 12psi from what i've heard, but don't hold me to it. But I believe the two reasons to get the head shaved are because the head is not flat enough or to make a smooth surface for the mhg since it needs to be as smooth as possible. So as long as you made sure to clean the surfaces and threads well then you should be fine with lower boost levels. But as far as your torque spec, I assume you mean ft.lbs.. Did you use arp head bolts , because that spec seems high even for them? I did 90lbs on my studs with the moly lube. Also did you follow the patten for tightening and do it in three passes?

yes. 3 passes of 30, 60, then 90. Arp head bolts. We already shaved the head when we put the new stock gasket on. Im just wondering if I would be able to do the stuff that suprra_girl has posted in her sticky thread on the stock gasket

Is it true that after 1000 miles i should retorque all the headbolts? i remember seeing something about it but i just dont see why i would need to if they are already at 90fp

it cant hurt to recheck after doing that big of a job. thermal expansion and vibrations can cause a small amount of loss, so checking them after a break in is a good check up.

damn it that sucks cause its such a bitch to do

Don't recall if Arp headbolts require a retorque or not, but standard ones do, recommended after 5 or 6 thorough heatsoaks of the engine. Probably wouldn't hurt to check your Arp's anyway, just to make sure they were all torqued evenly the first time around. Also, make sure you only do one bolt at a time and in the proper order, and only crack it loose a little before re-torqueing it. You don't want to risk the HG shifting even a miniscule amount.

If I had caught your thread earlier I would have recommended replacing the heater union bolt and hoses on the back of the engine. The bolt tends to corrode and leak after a few decades, and the hose back there ages poorly as well. With the head off they aren't too bad to replace, but a cast iron bitch with everything in place.

yes replacing the hoses in back should have been something i thought of right away. Haha. I already blew a cooling hose for my turbo. The whole shit was spraying out onto my headers and smokin like crazy. Thought i blew my HG again. lol. I suppose i could retorque them. why do i have to loosen them a bit again? cant i just set it to 90fp and have at her in the proper order?

I don't know all the reasoning behind it, just that all the better 7M mechanics whose opinions I trust (they generally know what they're talking about instead of just pulling figures and info out of the air) tend to recommend doing so. I think it may have something to do with the tensile characteristics of the bolts after they've been heat soaked a few times, but that's just a guess on my part.

i would just set to torque and go again on them, just as youd do if that car was all stock and hadnt blown yet.

Almost ready to retorque. I am also sea foaming the gas and oil right now and then before i change the oil im running some through the break booster to watch all the pretty white smoke. Also gonna change my spark plugs. One other thing i am curious about is where i might be able to get new splash shields for the wheel wells. The guy before me didnt replace any of the clips he broke when putting in the intercooler and the tire destroyed them.