1989karr

Ok, everyone is talking about the 3.4 swap and its starting to make my mouth water! So I was wondering......is there any way i can test it first??? In other words, if i drove a 4th gen with the 3.4 is that the kind of performance I can expect if its in a 3rd gen?

Project: 85 2.8 bird

pretty much,except not as good looks

Doward

Better - the 3rd gen V6 is lighter than the 4th gen V6 car

kretos

like doward said we have the lighter car

drdave88

iTrader: (3)

night and day difference man. if you go that route, do some of the other engine mods before the 3.4 goes in, itll just make it that much sweeter.

KED85

If you haven't read my tech thread, please do so.
Of atleast over 100 swappers, only one wasn't pleased with results.
Look, seriously, IF ya wanna win every race using 3.4 power
YOU WILL NOT
BUT
In end, you will have more fun trying!
The engine, seriously, makes the current car you own, perform like it always should, IF ya do the swap right.
In the end, it's also boring to look at. IT looks exactly what ya started with, a 2.8-3.1.
PS Easier to pass with smog, that way!
My car pulls like a freight train, it's such a wonderful powerplant upgrade.
Ya get to reuse nearly every part under your current hood.
This is a very worthwhile swap
ONLY
IF
YOU
TRULY
LOVE
YOUR CURRENT CAR!
IF not (this swap is, reality, labor intensive & not exactly cheap-but very detailed and simple!)
sell your current car & go buy/invest your money-time into a newer ride or a V8 3rd gen.
Seeking 3.4 used long block, low miles, from ONLY 1993-95 F Body RWD. No FWD 3.4 alllowed, cause it won't work.
Avg. location of engine cost is $500.
Latest good score was $650 for a used 40,000 3.4.
I've paid $800-$900 for my two. See below
Price a rebuild lately & see how I still came out ahead in powerplant upgrade for less.
Good luck with your decision.

Dale

iTrader: (12)

It will be slightly different as the 3rd gen intake is more for torque, where the 4th gen is more for rpm/top end.

Timing is slightly different as well.


I noticed a somewhat different, not as much as really expected. However, the feeling of knowing EXACTLY what I got under the hood, 55k miles on the engine (rather then 200k), better mpg, and pleasure of saying "I did that, aint it nice" was what I enjoyed the most.

Dale

iTrader: (12)

oo, and if you got a slipping 700r4, you can kiss that baby good bye, and all your work.

You wont notice a bit of difference, as well as you can expect that tranny gone in a few months.

The_Beast

Hey now.......what about a 95+ 3.8 swap? Can't that work?

drdave88

iTrader: (3)

just ask project85, the 3.8 swap is a nightmare.

The_Beast

dang dude.....3 minute reply. You ever thought of being in the postal service? lol Anyway I was looking forward to a 3.8 Is it really that bad of a nightmare? Not even worth its better performance?

Naft

if your thinking 3.8, think v8 instead. project85 can give you a firsthand account of why. or just search for it, or go to his cardomain page.

The_Beast

Well the reason I'm sticking with v6 is because this is my gas mileage maro. And I dont really want to go with the 3.4 because thats kind of disappointing to go through all the trouble of an engine swap just to end up with a 20 hp gain. I was looking forward to the added gas mileage and nicely added power the 3.8 would offer. I do wanna hear about Project85's fun though.

Dale

iTrader: (12)

Latest service I got the from the post office, you would have never gotten an answer, or about 2 weeks after you needed something.

The_Beast

Haha. Thats why I elect drdave88 as headmaster postal man

drdave88

iTrader: (3)

it was a one time thing, im not usually that bored and slow at work, lol. if it pays better than this one, ill take it.

1989karr

dang haha...I guess first thing is first...tranny needs a rebuild! .......and my latest postal service thing??? haha "oh...it's probably somewhere in the middle of the Pacific right now on a boat" lol

82-T/A [Work]

It's a direct bolt in.

However, unless you got the 3.4 really cheap, it's only worthwhile doing the swap if you already have an MPFI 2.8 or 3.1... otherwise you might as well just go through the hassle of dropping in a V8.

But, that said.. the 3.4 puts out 20 more horsepower, and about 25 more foot pounds of torque stock.

There are quite a few things you should do to it though before you do the swap:

1 - Port-matching the intake pieces
2 - Cleaning or replacing the injectors
3 - Roller Rockers (1.52:1 or 1.6:1)

You may also want to consider a cam... an H260 or an H272 (depending on what roller rockers you want to go with)

I'd also recommend keeping the intake from the 3.4. It'll make the swap harder (throttle linkage and whatnot), but the stock intake plenum you have is seriously restrictive to the 3.4. As a matter of fact, it's even somewhat restrictive to the 2.8 you already have.


Hope that helps.

Naft

and dont think of it as just a 20 hp gain, think of it as a 15% power increase! thats like bumping up your compression almost 4 points . . . or 3 psi of boost . . . and instead of putting more wear and tear on your engine, it takes off anywhere from 100-200k miles!!! all for well under a grand. I dont see how anyone could say no. "later" sure, thats what im saying right now, lol. but its an offer you cant refuse.

3.8 is only practical if you are trying to be innovative or unique. the 3.4 swap is a "boogie", the 3.8 a "nightmare"(for only a few more cubes too). plus the 3.4 has the advantage in that anything you do to your 2.8/3.1 will carry straight over.

KED85

Regarding intakes
IMHO
I feel the 2.8 designed intake is the winner
Why
One it handles the output requirements of a 3.4 with ease (ease of fit & responding to the 3.4 provided power gain now under the intake setup without any modification-install & go)
Two the 3.4 intake set up was desinged for a far more restrictive hood/engine location requirement, making it "more restrictive" to air flow increase. The 93+ is a very flat hood design & engine "part way" under the windshield, for max aerodynamics.
Three the 2.8 intake comes apart, by design, for way easy modification access. How ya gonna reshape that sharp bend "up top" of the 3.4 intake?
Again, my feeling on the 3.4 intakes I have removed from my donor 3.4 engines. Beyond real world usage, nothing else to respond to (no dyno testing results I mean).

82-T/A [Work]

As far as horspower goes... the air volume of the 2.8 plenum is quite a bit less than that of the 3.4 plenum.

The flow of the 2.8 is actually restricted by the stock intake on anything higher than 4,500 rpms.

With a 3.4, you'll really lose a lot of that mid-rpm power with the 2.8 intake.

You can just as easily use the 2.8 intake, but if you don't mind using the 3.4 intake, you'll have more power.

The_Beast

Anyone have any more tips on which parts to use with the 3.4 to get the best performance out of it?

drdave88

iTrader: (3)

no offense to anyone on either side of the debate, but does anyone have hard facts (numbers) to prove or disprove either side of this? just from looking at the intakes, and i havent really studied them, they both look like they have a pretty harsh angle going down to the runners. but the 2.8/3.1 intake can be taken apart to P&P to improve that. the 3.4 cannot. so wouldnt the 2.8/3.1 have more potential, even IF it is more restrictive stock?

ok, if you want the most performance out of it, yes P&P the heads and intake, 1.6 roller rockers, cam, underdrive pulley, lower temp t-stat, ignition upgrades, A/C delete and smog delete (if applicable), weight reduction, just search for "mods" and youll find more info that you want on the topic. check out our sites and sigs to see what we have done, check your budget, and go from there..... oh yeah, posi!!!!!!!!!! mine goes in tomorrow

The_Beast

haha nice. ok thanks.........by the way.....P&P?

KED85

Port & Polish
Nah my 2.8/3.4 set up gained such a wonderful flat torque band, it's a dream come true for making a 3rd Gen a decent ride & performer. I also increased gas milage!
Ya can't "use" a 3.4 intake set up under a original 2.8-3.1 hood, unless ya wanna re-engineer a wheel.
I was most impressed wit the 2.8 intake ontop of my 3.4 mill.
A 2.8 will always move less air than a 3.4.
2.8 is smaller.

The_Beast

drdave.......lol guess I should have been more specific. By "best performance" I was talking more along the lines of small things, like using the 2.8/3.1 intake with the 3.4. Things that will keep the same or increase the gas mileage while getting better performance out of the engine before it goes in the car. Thanks Though.

KED85

You mean like this?

KED85

And This?

The_Beast

haha. I dont know about anyone else but I need some descriptions of those pics

KED85

Look at my signature!
Read my Tech thread about how to do the swap.
That's your answer!
You're welcome.
Yep that's all 1985 induction/ignition/exhaust systems bolted to 1995 3.4 long blocks.
No engineering involved.
"Unbolt old stuff swap onto new donor low milage 3.4 engine".
Drive.
It does work
And it works (after teething pains!) quite well.
Again over 100 swappers and so far only one not pleased with swapping results.

82-T/A [Work]

I don't have anything I can link you too...

But I do know that for Fiero owners, this is a very popular swap. The only change we have to do as Fiero owners is drill and tap bolt holes for the starter motor on the opposite side.

I do know that several people have actually measured the CFM of the intake plenums on the flow bench.

Now, I could be wrong, as it's been a while since I've looked at it... but ALL gen 1 motors (a 3.4 V6/60 in the camaro / firebird is also gen 1) have identical intake manifolds. This piece being the bottom most piece that actually bolts to the engine.

The piece in the middle are the intake runners. Now, I know this piece is IDENTICAL between you Camaro / Firebird guys, and Fiero owners. This piece is identical for all 3rd gen MPFI f-bodies.

Now, correct me if I'm wrong, but I believe that the 93-95 Camaro / Firebird 3.4 V6/60 ALSO has identical intake runners.

The NEXT piece is the intake plenum.

EVEN if the runners don't change between the motors, I know that the lower intake manifolds are absolutely identical, this means that you can bolt the entire intake assembly from the 3.4 onto the 2.8 without any problems. The only problems you may run into are possibly throttle linkage and whatnot.

I've owned only V8 third gens, and I know that there was plenty of room for me to put an open element air cleaner on top of a big 4bbl carb with an Edelbrock performer on a V8. So, with that in mind, I don't see how a V6/60 (even being 60 degrees as apposed to 90 degrees) would have problems bolting the 3.4 intake plenum in place of the 2.8 intake plenum.


Now, you can take my word for this, but the 3.4 intake WILL flow better than the stock 2.8 intake.

The restrictions in the 2.8 intake are not in the runners, but actually in the neck of the intake plenum, directly behind the throttle body. Believe it or not, the neck actually decreases in size right after the throttle body. It shrinks to about 3/4ths the actual TB size.

And whoever said "perfectly flat torque curve", I mean this with the utmost repsect, but the 2.8 or 3.4 are probably one of the motors that has the least flat torque curve.

Compare the V6/60's torque curve with that of a DOHC V6/60 or a 2.4 TwinCam.

The V6/60 has a radical torque curve which builds strong, but then drops off really quickly around 4,500 rpms.

The reason for this is specifically because of the restriction in the intake.

I've upgraded my 2.8 into a 3.2 with 3.1 crank and rods and an overbore piston to increase compression and slight displacement.

The motor totally drops it's power around 4,500 rpms.

You don't notice it as much on a stock 2.8 because the intake barely restricts this part of the motor, but when you increase the displacement, this restriction becomes greatly more apparent.



Unfortunately, Fiero owners CANNOT use the 3.4 intake, not because it doesn't fit, but because the throttle body is facing the opposite direction. (the air intake on the Fiero is facing the rear of the motor).

If anyone would like to really tell the difference, get both, and run both with a g-tech, or at the track... you'll see without a doubt that the 3.4 intake will totally improve power above 4,500 rpms./

cooltc2004

iTrader: (4)

So wait, if I drop in a 3.4, can I just change the chip to meet its stats, right?

KED85

I recall ya :>
What I mean is the cam profile of 3.4 plus the added torque from added cubic inches
is a flat strong climb to the "RPM" end and yes it tops out about high 4,000 RPM range.
That point is not important to me.
I have hills to climb out here & loads to haul.
The 2.8 was gasping for breath.
The 3.4 is effortless power to spare.
60* mills sit higher in the engine bay than V8s!
I don't street race my 3.4 sets up.
I have an old Corvete that's better prepped for making tracks on the street.
My swap is for power & cheap engine repair (killed my 2.8 & it is cheaper to do this swap than rebuild puny little engine!)

KED85

There is NO NEED to change the PROM or Chip.
None what so ever
Is it possible to change the chip to increase performance after 3.4 swap?
I did not change any ECM stuff when I upgraded in power.
If I "lost" any power (doubt it), it makes no difference to me.
I have old Vette & old 60's Camaros for those needs.
I did my swap for cheap engine repairing & the benefits of a bigger engine.
Works great by me & over 100 swappers, too.

82-T/A [Work]

As KED85 said, there is no need to swap out the chips. As a matter of fact, they wouldn't work anyway. The 93-95 Camaro is a Sequential Port Fuel Injection system while the 3rd gen has a Multi-Port Fuel Injection.

The 3rd gen basically squirts fuel in a two-batch mode system. The fuel basically sits at the top of the intake valve for a split second before the valve opens.

SFI, merely squirts the fuel a split second before the valve opens. SPFI offers no increased horsepower, but it does offer slightly better fuel economy (less fuel is wasted in the lower RPMs).


Aside from the fact that it wouldn't work... think of the 3.4 as basically being... "More of the same..." in comparisson to your 2.8.

Your 2.8 computer doesn't need to know that the engine now has more displacement. However, in order for it to put out more fuel, you'll need larger injectors. You'll want to keep the injectors from the 3.4. Or... if you have a little bit of money saved, get yourself a brand new set of 17lb injectors from Accel (get the pintle style, not the rotary disc type... the pintle ones are better suited for performance).


Also.. depending on the year of the engine you're replacing... your motor may be balanced differently than the 3.4 (3.4s are internally balanced). I'm not sure if your motor is internally balanced also, or externally balanced... they switched on some year.. (1988???).

Anyway, you'll wnat to make sure that you keep the flywheel / flexplate from the 3.4 and use that with your transmission. Don't use your 2.8 flywheel unless you know that they both have the same balance.

cooltc2004

iTrader: (4)

I have the 3.1L in my 1992, so I take it from the year you gave me, my engine is internally balanced?

82-T/A [Work]

To be honest, I have no idea, but I'd suspect that it PROBABLY has the same balance as the 3.4.

But... just to be on the safe side, get the flywheel with the 3.4

Or at lest double check somewhere (here?) on whether or not your motor is internally or externally balanced.

Naft

internal balance started late late 86 . . basically 87, i think only a handful of 86 blocks were internally balanced, if any. for sure 87+ are all internally balanced.

The_Beast

Oh sorry man. I didnt know that was you that did that swap. Yea thank you.

kretos

only question i want answered is, can you use the old 2.8 fuel rail, i would assume yes with the 17lb/hr injectors, but i remember reading on here you needed the 3.4 fuel rail.

drdave88

iTrader: (3)

2.8 fuel rail works just fine

KED85

Simply put
You are putting the original vehicle induction/ignition/exhaust system on the new donor engine.
Retain from 3.4
larger injectors & insert those into 2.8 fuel rail (the shower head ones come on the 3.4, is that pintle style? I heard better cleaniness over "easier to clog" pintle!)
3.4 Balancer & Flywheel or Flexplate
Put that all "together"
Insert into original vehicle engine bay
Hook up wires
Done!
Add new stuff as necessary & also while at it take with your purchase the 3.4 FRAME Motor mounts. they are 10 years newer than your original ones. 93-95 3.4 frame motor mounts also fit & used on my 1985 Blazer.
Find my tech thread, read it and seriously 99% of questions are "answered".
Rest of questions are answered when the two engines are out of cars side by side.
You will then fully understand why "certain swap things" won't work (without re engineering the wheel) under original vehicle hood.
Over 100 happy swappers now, one dissenting swapper.
Used 3.4 long block latest great score was at $650 for a used 40,000 mile long block (with tranny!!!!).
It is a great alternative to rebuilding that puny little engine ya now got. And way less expensive. With better results in the end!

kretos

i had planned this swap a while back, but finding the motor's up here is a rarity, i have however come across a 3.4 long block (crank rods and such) i already have another 2.8 thats complete. now i remember asking a while back about the flywheel, i got told to use the on eoff the 3.4, but i canm't get one off a 3.4, only a 2.8


i figure for the 250 it would cost me it would be much better to grab it, but if i need to grab a ton of things to make it work (new injectors are only 250 so its ok) i might as well just stroke out the 2.8

82-T/A [Work]

Make no mistake about it though... the 3.4 is swap is basically the best, most cost efficient swap you can do to an MPFI 3rd gen Firebird.

kretos

ah but i have a camaro

lol

still need an answer about hte flywheel to make up my picky mind, i'm sure i can use the 2.8 since its balanced the same as the 3.4 but is there any size difference?

Naft

87-95 60*v6 pushrod engines use a neutrally balanced flywheel, all of which are the same size/teeth count. you're good to go.

82-T/A [Work]

Well, not ALL 87s. In the Fiero, it was still externally balanced. They didn't go to internally balanced motors until 1988.

I think that might be the same for the J-body too...

KED85

ANY
machinist or tranny shop or driveshaft shop
can "fix" that balancing problem.
the proper 3.4 balancer IS a must, tho.
Rest is put it together......
It's fun!
And read my last sentence about that Puny little 2.8......
Really do the work right, worth it!
Plan. It's cheaper than a mistake.

kretos

i'd just go out and buy a new 3.4 harmonic balancer, this has without a doubt made up my mind, not worth stroking out the 2.8 i'll just grab the 3.4 longblock and giver.

good thing i wasn't ordering parts until next week

The_Beast

Better change your sig then kretos