3.4L GM engine question

Is the 3.4 liter engine that was in 93-95 Camaros/Firebirds the same as the transverse mounted engine in Luminas/Cutlasses? If so, do they all have the same trans bolt pattern as the 2.8L? DOHC?

Thanks, Ken

Reply to
GWHSU
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I can't answer your question at all, but wanted to comment a little on this engine.

I believe that the 2.8 and the 3.1 V6's are of the same parentage.

The 3.4 DOHC was an engine I wanted to use to swap into my project RX-7 UNTIL I did a little checking on it. Apparently, this unit was full of problems.

If anyone can comment on the 3.4 DOHC, I would find it very interesting.

Reply to
Larry Smith

Reply to
David J and Lynne J Shepherd

"Larry Smith" wrote

Larry, they only really had two major problems....the same o-ring seal leak from the oil pump drive that all the GM 60 degree engines suffer from. This has been cured by the release of a tan colored o-ring that does not get hard with age.

The other problem was the plastic timing belt idler pulleys would wear out and cause timing belt problems. Because of the way the engine is situated in the vehicle, it is a bit of work to replace the belt and to replace the alternator. If you used this engine in a rear wheel drive car, you would eliminate these two problems as the front of the engine would be quite accessible.

Other then that, very tough engine. If you were going to use one, I'd pull both cylinder heads off, replace the head gaskets, and the oil pump drive o-ring with the new updated one (you can also install a paper chev small block distributor gasket as extra insurance) replace the timing belt and all of the idlers pulleys and tensioner pulleys. She would be good to go then.

Ian

Reply to
shiden_kai

The reason I asked is because the 3.4L GM crate engine (or one from a camaro) is often recommended as an easy replacement for the 2.8 in pickups and suvs. I have a 96 Olds with a 3.4L and yes, the alternator is in a very bad place. For example, alternator replacement on this engine requires about the same amount of work (or more) as timing belt replacement for some other engines. Replacment will run about $400 at a discount store. When I got mine replaced at about 100k miles I specified a new part because "God knows we don't want to do this again!", I said. Guess what, it failed in two weeks. The engine is strong and reliable and if it was in a rear-wheel vehicle I would like it. The only other problem I had was a fuel pressure regulator that leaked raw gas into it vacuum line. It started so slowly that it took me months to find it-a stalling problem with no codes set. I have the '96 Olds model spec'ed at 210hp while the following years are 190, I think, and have no idea what the differences are. Still wondering about the replacement for the 2.8. Personally, I'll take a timing chain and forego the dohc, especially in my suv.

Thanks for the replies, Ken

Reply to
GWHSU

Ian, I read something about gasket leaks with this series of engines as well. I'll have to go back and see if I can be more accurate, but allegedly this effected the 2.8 as well. I had one car with a 2.8, and I have never had a better, more tractable and trouble free engine.

If there were an internal leak problem, it must not have been in all models.

Reply to
Larry Smith

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This link gives a brief discussion of the problems with some of the small V6's

Reply to
Larry Smith

There are two DIFFERENT 3.4 engines. One is a belt-timed overhead cam engine which developed a reputation as an unreliable maintenance-hog almost as soon as it was released (and according to a Delco powertrain control insider I used to know, it was ONLY produced in the first place because the Chevrolet division didn't want the far superior Buick 3800 used in "their" cars.) Fortunately, the OHC 3.4 was pulled from production after only a few model years. The current, more common one is a chain-timed OHV, and is basically just an upsized 2.8/3.1. It is this "crate" engine, not the problematic and out-of-production OHC, that is spec'd as a replacement for the 2.8, because external dimension-wise it IS a 2.8.

Reply to
Steve

"Larry Smith" wrote

Hey, one of my pictures even shows up on that page!

Good pictures, but the site does draw some false conclusions when it comes to the cylinder head gaskets.

Ian

Reply to
shiden_kai

"Larry Smith" wrote

Ok, the 3.4 DOHC engine, while based loosely on the rest of the 60 degree GM v-6's does not use the same style of "wet" intake manifold that the other one's use. The intake manifold on the DOHC engine does have a water passage that connects the two cylinder heads at the rear, but there is no open valley in the block on this engine. So even if the intake manifold gasket were to leak antifreeze (was rare, totally different design), it couldn't get into the engine.

Ian

Reply to
shiden_kai

Aside from all the other rather good info provided on this engine, I can say one thing more. The starters are on different sides of the block depending on whether the engine was used in a longitudinal orientation like Camaro, or transverse orientation like all the front wheel drive cars. The block should have the bosses cast into it for mounting on either side, but only one side will actually be drilled and tapped for the starter bolts. So if you change orientations, you'll have to bet a machinist to drill and tap the starter bolt holes to relocate the starter. There may also be the need to deal with drilling out a tranny bolt hole or helicoiling it to add threads, depending on which way the conversion goes.

AFAIK, the tranny bolt patterns are the same.

JazzMan

Reply to
JazzMan

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