DOHC Performance Build

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I dropped my spare motor off at a local machine shop this afternoon. The forged 8.5:1 pistons and rods I bought 7 years ago will finally be going in. I also ordered ARP studs for the crank from WOT Tech. I was looking for head studs, but all I could find was one mention of ARP head studs and another of Raceware head studs. I'll have to follow up on those to see what I can find. I also need to follow up on the copper Flatout head gaskets or Gaskets to Go MLS head gaskets. I'll post pictures and more info as I have it.

Tim

[NateD4]

I'm not sure what WOT has for the 3.4 DOHC engine, but have you checked out Cometic head gaskets? As for head studs if you can't find any let me know. I can get custom head studs made.

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It looks like ours are the same as the Northstar and they use VW 204-4204 ARP head studs. Two sets on Jegs is $258 shipped.

Next up on the list is seeing if I can find MLS head gaskets that don't take months to make/order.

Tim

[jman093]

It looks like ours are the same as the Northstar and they use VW 204-4204 ARP head studs. Two sets on Jegs is $258 shipped.

Next up on the list is seeing if I can find MLS head gaskets that don't take months to make/order.

Tim

Let us know if you find anything. And what ARP main bearing studs fit an LQ1? I have some ARP rod bolts, but I thought nothing fit the mains right.

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One of the Fiero guys used MLS gaskets from Gaskets to go. They're overseas. The gaskets looked great, but I'll probably only go that way if I have problems.

I talked with my engine builder about the Flatout RCC copper head gaskets and he advised using stock head gaskets instead. It sounded like copper just isn't meant for the street.

Here is the main stud kit from WOT Tech:

http://wot-tech.com/shop/gm-60v6/main-stud-kit/prod_91.html

Tim

[RedZMonte]

Nice to hear she is starting to go together. Is it a '96-7 LQ1 or what year motor?

S

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It's a 97. I bought it with the complete engine harness and PCM. I also have a 96 harness in case I want to keep my 4T60E for a while.

Tim

[Dave96z34]

Do a 284 swap I would never go back to the auto I absolutely love the 5 speed. If you need help with the tuning for the 5 speed I can help you there.

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Do a 284 swap I would never go back to the auto I absolutely love the 5 speed. If you need help with the tuning for the 5 speed I can help you there.

I've considered it a few times. You've been tuning your factory 96 computer for the 284?

Tim

[Dave96z34]

I did it on my 97 set up but 96 will actually be alot easier to do.

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Hmm. You've really got me thinking about it. I think I may have found a complete 284 donor car. I already have a built 4T60E, but I was hoping to build a 4T65E-HD I have. I just wasn't looking forward to the expense and trouble of the rebuild.

Tim

[SappySE107]

I would OBD1 swap long before i ever considered OBD2 for what you want to do. I have a 92 with a 284 and built DOHC with 97 monte computer. Its ok for NA, but id ditch it in a second with boost. OBD1 can do a better job, or megasquirt.

Edit, 91-93, or Nast1 or code 59 or anything along those lines. 94-95 DOHC is just not going to catch on, ever. The MAF tables are setup horribly.

[Dave96z34]

I would OBD1 swap long before i ever considered OBD2 for what you want to do. I have a 92 with a 284 and built DOHC with 97 monte computer. Its ok for NA, but id ditch it in a second with boost. OBD1 can do a better job, or megasquirt.

Edit, 91-93, or Nast1 or code 59 or anything along those lines. 94-95 DOHC is just not going to catch on, ever. The MAF tables are setup horribly.

OBD 2 works just fine I ran boosted 4 years with out problems. If you feel the need to be special get a haltech EMS.

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I already have both a 96 and 97 harness with computers, an AeroForce Interceptor scan gauge, DHP, and HP Tuners, so at this point it's going to be OBD2. For the 95, the wiring swap doesn't seem too complex.

Anyway, here are some pictures of the new, old parts. Most have been posted before, but threads are worthless without pics. (The turbo in the first picture is a T67 compressor and P-trim T4 turbine with a dual ball bearing center section. It uses the small T04E compressor cover so it will swap directly in place of my current setup. The normal T67 compressor housing is HUGE and would require redoing the entire set of hot and cold turbo piping.)












Tim

[SappySE107]

OBD 2 works just fine I ran boosted 4 years with out problems. If you feel the need to be special get a haltech EMS.

The difference between just fine and perfect is knowing what a fully programmable setup does vs a limited tuning solution. You could run a carb on a boosted 3.4 DOHC just fine too, and that would be special.

I have nothing more to contribute to this thread, good luck.