The 15 Y/O Turbo M42 Build Thread (Now Holley EFI Terminator X Controlled)

[BUDNUNTA]

Did you think about put putting in one of those .140 MLS gaskets?

e36 guys are running those up to 20psi

[Dj Buttchug]

Did you think about put putting in one of those .140 MLS gaskets?

e36 guys are running those up to 20psi

theres really no reason to because im running lower compression pistons...

[325ix]

That is some serious quality work there. I really like this car overall. makes me wanna go turbo my m20 now!

[sweet6e30]

me like dis!

[Dj Buttchug]

can anyone tell me how a map sensor taps into intake piping. What size thread is normally used with PNP megasquirt kits? I may just have to call d tech tomm and ask.

Shits almost ready for tune time.

[Danny]

Map sensor or the IAT sensor?

[Simon S]

The thing with your first head gasket is really bugging me. I keep thinking about it.

Am I to understand that after ~100 miles, some of the head bolts were finger tight?

When I recently put my [first] head on – it took most of my strength and a 2’ breaker bar to get that last 90 degree turn done. I usually put loctite on everything – but went with oil per directions – thinking to myself oil would be ideal in the threads as the bolts stretched.

That would’ve pissed me off to buy all new head bolts again. Shit.

[e30guydownunder]

Simon, AFAIK old mate is running ARP studs. However ARP directions do state to re-torque and re-torque after the first few heat cycles. Was this done?

[Dj Buttchug]

Map sensor or the IAT sensor?

possibly both. Ms uses either or?

The thing with your first head gasket is really bugging me. I keep thinking about it.

Am I to understand that after ~100 miles, some of the head bolts were finger tight?

When I recently put my [first] head on – it took most of my strength and a 2’ breaker bar to get that last 90 degree turn done. I usually put loctite on everything – but went with oil per directions – thinking to myself oil would be ideal in the threads as the bolts stretched.

That would’ve pissed me off to buy all new head bolts again. Shit.

I feel like my engine had demons... I cant explain some of the issues ive had. ARP bolts can be reused up to a certain point of stretch. Mine were in spec so I went ahead and used them again. As far as the gasket... I have no idea. Ive had such shit luck with VR so far

Simon, AFAIK old mate is running ARP studs. However ARP directions do state to re-torque and re-torque after the first few heat cycles. Was this done?

Elaborate on this. The car is back running fine with no leaks. Should I re torque again?
I used robs advice when torquing my head down. He said he went 30lbs... rest for 15min, then 60lbs. then 70lbs final on his turbo race car.

I dont recall ARP stating that a re torque after initial heat cycle was needed...

[Danny]

possibly both. Ms uses either or?

MS uses both. The IAT sensor is threaded (looks like a coolant temp sensor) and you can either jb weld it into your cold side charge piping or weld/jb weld a bung and thread it in. Wire the signal wire from the IAT to the Purple/Gray wire in your AFM harness. (I think, hopefully someone will confirm this.) And the other wire to ground. Map sensor SHOULD be on the MS, if you have a picture of the board I can confirm this. You just run a vacuum hose into the glovebox for that.

[Suspence]

i want turbos.

[Dj Buttchug]

MS uses both. The IAT sensor is threaded (looks like a coolant temp sensor) and you can either jb weld it into your cold side charge piping or weld/jb weld a bung and thread it in. Wire the signal wire from the IAT to the Purple/Gray wire in your AFM harness. (I think, hopefully someone will confirm this.) And the other wire to ground. Map sensor SHOULD be on the MS, if you have a picture of the board I can confirm this. You just run a vacuum hose into the glovebox for that.

awesome thanks man

[e30guydownunder]

Elaborate on this. The car is back running fine with no leaks. Should I re torque again?
I used robs advice when torquing my head down. He said he went 30lbs... rest for 15min, then 60lbs. then 70lbs final on his turbo race car.

I dont recall ARP stating that a re torque after initial heat cycle was needed...

Yep that is correct you work up to spec in steps but also after you have heat cycled the engine you are meant to check the torque specs again.

I couldn't find it on the ARP website, but am confident I read it in the lil yellow page of instructions that come with the studs.

A quick google brought up countless forums/threads of people having loose studs after a few hundred/thousand miles and wondering why they are leaking oil. Then everyone else would say you need to re-torque your studs!

I would run the engine for 10-20minutes say and get it up to temp (if you can go for a small drive, better) then pull it in home and let it cool down completly, a few hours, pull the rocker cover and re-torque. again in steps up to your final torque setting.

[Dj Buttchug]

Yep that is correct you work up to spec in steps but also after you have heat cycled the engine you are meant to check the torque specs again.

I couldn't find it on the ARP website, but am confident I read it in the lil yellow page of instructions that come with the studs.

A quick google brought up countless forums/threads of people having loose studs after a few hundred/thousand miles and wondering why they are leaking oil. Then everyone else would say you need to re-torque your studs!

I would run the engine for 10-20minutes say and get it up to temp (if you can go for a small drive, better) then pull it in home and let it cool down completly, a few hours, pull the rocker cover and re-torque. again in steps up to your final torque setting.

will do. I didnt do this last time. maybe this was the cause of my leaking hg.
thanks for the tips

[e30guydownunder]

sucks that this is probably what was wrong with the other HG, but by the time it was leaking oil it was probably blown anyway.

good luck at the tuners!