bored and stroked

[95firebird]

how do u no if ur engine is bored and stroked because everyone is always talking about how slow the 3.4 are well my car is not slow lol i raced my buddy today in it and i smoked his 3.8 and i mean bad and when i get into my moms 3.4 it does not have the power like mine and if im on the freeway and floor it the car wil go past 110 and stay pinned there so i dont know whats up cuz everything is stock

[poormillionaire2]

The only way to know for sure if your engine has been modified like that, is if you tear it apart and measure. But I have never heard of a 3.4 or 3.8 V6 being bored and/or stroked. Its not really worth the time or money. Is your buddy's car an auto or a stick? It could have been a driver's race.
Maybe your car has a chip in it or some sort of tune.

[blindeyed]

Well the 3.4 can't... or should I say shouldn't be bored or stroked. If it is bored, then the only safe way to do it would be to resleeve it. You have to look at the engines history. It was originally a 2.8L, was then stoked and bored to a 3.1L and then bored again to the 3.4L. According to GM, it is already bored to its max. If it was bored anymore then those cylinder walls would be way too thin. Not to mention that you really can't stroke it any more without hitting the cylinder heads.. But if you were to somehow get around that problem, finding an aftermarket crankshaft would be a miracle alone, so having one custom made would probably end up costing more than the car's worth.. so odds are there's no internal work of that sort that's been done.

You also have to take into consideration that despite displacement, not all engines run the same. Your buddy could need a tune up pretty bad if you smoked him that much. Plus, I also agree with poormillionaire, if he's a stick he could just be inexperienced and not be very good at shifting.

[FormulaLT1]

A factory freak 3.4, that would be the greatest shit ever . I have the same engine basically in my Achieva, its the 3.1 version but basically the same shit. They are peppy motors, I don't see how a stock one could take out a 3.8 but if the 3.4 was in tip top shape and the 3.8 was way out of tune or had some type of issue. I could see it pulling a slight win but not get smoked,

[95firebird]

his is a 02 auto and is in very good shape like i said when i got the car my mom even said it much faster then her and they are the same years and y when floored would it go past the 110 and get pinned there

[blindeyed]

Originally Posted by FormulaLT1

A factory freak 3.4, that would be the greatest shit ever

Shoot, it came close to that at one point. Check it:
http://www.berettastuff.com/reference/proto3.jpg

Yeah, it's not quite a 3.4 but it's close enough. It was a prototype, but man would that have been sweet if Chevy put that into production.

[95firebird]

if the car was chipped would it make that much of a diff

[MrPbody]

And which 3.4? There are three. There's the dual OHC version, which is an absolute BEAST at higher revs. There's the OHV aluminum headed one and the iron headed one.

We have routinely "bored" 3.4s to .020" over (.5 mm). No issues.

2.8 and 3.1 share the same bore size (3.503"). 3.1 and 3.4 share the same stroke ( 3.307").

All are pretty good engines. With a little head work and some creative electronics, the iron-headed 3.4 can make well over 200 HP, and still be useful in a "driver". If one were to go "the distance" with one of those DOHC version, WOO HOO!!! I have one "stashed" for a future Fiero project. FWIW, I drove a '94 or '95 GP GTP with the DOHC engine in it. It would easily outrun a '97 with the SC 3800, on the high end.

Jim

[95firebird]

how do i find out which one i have

[blindeyed]

Originally Posted by MrPbody

And which 3.4? There are three. There's the dual OHC version, which is an absolute BEAST at higher revs. There's the OHV aluminum headed one and the iron headed one.

We have routinely "bored" 3.4s to .020" over (.5 mm). No issues.

2.8 and 3.1 share the same bore size (3.503"). 3.1 and 3.4 share the same stroke ( 3.307").

All are pretty good engines. With a little head work and some creative electronics, the iron-headed 3.4 can make well over 200 HP, and still be useful in a "driver". If one were to go "the distance" with one of those DOHC version, WOO HOO!!! I have one "stashed" for a future Fiero project. FWIW, I drove a '94 or '95 GP GTP with the DOHC engine in it. It would easily outrun a '97 with the SC 3800, on the high end.

Jim

Well the one that came in the Firebirds and Camaro's is the RWD 3.4, cast iron head one. So that's the one I was referring to. I just go by what GM recommends and suggest not boring the engine. I'm sure it would probably even withstand a .030" bore, but who knows, I'd just rather not find out.

[MrPbody]

Sorry, I should have been paying better attention. I KNEW the F-bodies only came with the iron-headed version. Brain fart...

You CAN have the bores sonic-tested. If there's at least .180" on the thrust side, AFTER boring/honing, you're fine. Aftermarket pistons and rings through .75 mm are readily available.

Jim