FbodTrek

I was planning on building up my 2.8, but it turns out I can get a 3.4 for 350$. My question is, how much torque and horsepower do they have? What kind of times do converted thirdgens run with the 3.4? Can I just swap the intake and drop it in? Thats it, thanks.

AM91Camaro_RS

i don't remember all the numbers on the 3.4s but for $350, i say do it. later yo ucan do a cam and stuff and make lots of power. yes, you can just drop the old intake on...i'd do some P&P first though.

6SPEED84Z28

iTrader: (1)

160 hp at 4600 rpm

Project: 85 2.8 bird

50 of them now, damn !!!!!!!!

:rockon:

Dale

iTrader: (12)

160hp, 200tq

I've got one up my sleeve, just waiting on some equipment to show up so I can go get the beast

So I shall make 51 or 52

Not sure if my truck was counting as one or not

KED85

Blessed thing is that this swap has "caught on". All those that put out personal effort to obtain a 3.4 from the 4th gen F Body, ya save alot of $$ over new crate & ya keep a legend on the road, alive & stronger.
I guesstimate atleast 50-ish I've coached, suggested, seems like they did the 2.8->3.4 long block swap boogie.
We can imagine there are more, but really, good for us to have enjoyed a great way to skin a cat on the cheap & high on enjoyment factor.

I've read our 3rd Gen rides are quite a good chassis (which need a bit of flex fix here & there). But quality wise, it's a real good foundation.
I agree.
My 3rd Gen is functional, aesthetic pleasing (when I swap on my other front end painted now piece!) and 90% of the "options" work!

FbodTrek

I wasn't aware that the torque wqas that much, I've driven a few 3.4 4th gens, they were slower than my 3rd with the 2.8. I guess they're heavier??? Why would I need to use the timing cover off the 2.8? Can't I just put the 3.4 in as-is (with the 2.8 intake, distributor) If it will slide right in like that, all the better, I plan on a same day swap (maybe two if i run out of juice). The last 3.4 I pulled was on a firebird, it came right out (although, the bell housing was a bit difficult to get at....). There's really not all that much to the 3.4. And, by intake you do mean the upper half right??? I'll just read the other post....Thanx for your time guys.

Project: 85 2.8 bird

Sounds like he wants to do my version of the swap

FbodTrek

What swap are you talking project?

Dale

iTrader: (12)

If you dont swap TC covers, you can not get an accurate timing setting.

TQ was actually like 198 or something Might as well be 200

Project: 85 2.8 bird

That's the pic of the 3.4 coming out of the bird. 85 intake reused, all 3.4 accessories minus a/c, and no timing teeth on it. I transferred the timing teeth off the 2.8 & put it in the best "approximate" location on the 3.4.


edit: If yo look closely @ the crank pulley, you cain see the tube thing that's on the teeth bracket sticking out.

FbodTrek

The timing cover swap is for timing reading only? I plan on ditching the A/c anyhow (my compressor is junk, and i've never had A/c on any of my cars, i roll with the windows down). I kinda wanted to be able to drive my car as is, while I am busy replacing seals and gaskets on the 3.4 (can I use the water pump thats on the 3.4? And, about the oil pan, will the 3.4 one clear the crossmember on the 86? Thanx project (et al.) A 25% power increase for around 500 dollars...sweeeeeeet.....

Project: 85 2.8 bird

you can not reuse the 3.4 water pump on the 2.8/3.1 as it rotates in a reverse direction. As for the 3.4 oil pan, I had ZERO clearance issues.

KED85

When I did the swap, for my version (all engine swaps are custom projects) I kept all original vehicle timing cover/oil pan/water pump/pulley stuff. Don't forget to swap oil filter housings, too!
3.4 upgrade is such a simple way to accomplish what I wanted, to run all factory optional AC stuff, easily.
My other need was passing smog testing in CA, stock 1985 look was mandatory. And I also wanted swap accomplished in quickest turnaround off road time.
I had to Boogie quickly doing this swap which took me about a month. Reassembling the 3.4 long block with original vehicle stuff is easiest sure thing method. No guessing or re-engineering at all.

Yeah the pans can fit. But in my case, I've used 1985 pan for my pic below.

That's my 1995 3.4 in my 1985 Firebird.
Smog guy never thinks I've swapped engines, only that I kept engine bay clean.
I did same thing for my 1985 Blazer, I went & rebuilt my 1995 3.4 in that vehicle as a 1985 factory delivered carb'd engine, for passing smog as my primary goal & cheap powerplant upgrade.

When done the car pulls like a freight train, so much torque, it'll make ya giddy!

I wrote the engine swap thread to pass along what ya run into doing the swap boogie, to make your conversion quicker & easier.
It's really is bloody simple project with great dollar & physical effort worth it, accomplished by paying attention to every engineering detail.
Fix everything ya can during the conversion. And you already possession 90% of what ya need to make swap under your hood, work right, the donor 2.8 with all the spare parts!
I've driven about 13,000 trouble free & easy passing CA smog testing (twice!) miles after the swap. Wih many more miles & smiles to go.
Consider keeping AC. The AC system works better with a more powerful engine.

Only better swap is selling your current ride & finding a strong running V8 car. $500 for this used low milage former running fully dressed 3.4 long block engine is a very fair value.
Ya spend about $100+ in gaskets & such, rest is just effort.
Add new tranny mount while at it, too!

LT1guy

iTrader: (1)

You sure about that? They looked identical, at least on redraif's 2.8 and 3.4...we used the 3.4 one, with the 2.8 accessories, and have had no cooling issues whatsoever. It runs just as cool as it did before, which actually is a bit too cool.

Project: 85 2.8 bird

3.4 wp rotates counter clockwise.

LT1guy

iTrader: (1)

Maybe the difference is with early (non-serpentine) 2.8s; Redraif's is an 87, and had serpentine like the 3.4.

FbodTrek

assuming I get the motor with all the accessory brackets: will the 2.8 accessories bolt up? As for the water pump, my setup is a v-belt one, so would I use my pump with my accessories? I can't stress enough that I plan the swap for two days-no more. I want to hit it in one pass. I need to know the easiest way to make it work, I had planned on a regular swap (kinda like just putting in a new 2.8). Pulls like a freight train huh? I can't say that THAT doesn't sound awesome! I'm getting excited just thinking about it now!

KED85

You're bound to hit a sang.
Again, for sure thing reuse all original vehicle 2.8 timing chain/oil pan. All your 2.8 original vehicle stuff will bolt back up.
Rip out your current engine & strip of the to swap stuff. Clean & prep & rebuild or upgrade the original stuff.
You'll be 2/3rds there.
Biggest time consuming detail is removing the recessed block plug, passenger side cylinder head. Ya get that plug out, you are all down hill on the swap. That hole is refilled by original vehicle water temp fan sensor.

FbodTrek

My coolant sensor is in my water neck. Why would I need to pull the head to do it anyway? Is this plug you speak of in the head or the block? The way I plan on doing it is : Tear down the 3.4, replace seals, lower intake gasket, main seal, timing cover gasket, waterpump gasket etcetera. I am not pulling the 2.8 out until the 3.4 is ready to go in-minus the upper intake manifold. I can pull my motor out in about two hours, swap the manifold to the 3.4 in an hour. When the 3.4 starts to go in, it outta take about 4 hours to have it ready. Hook up the cooling, fuel lines, and set the timing. I have a lift, hoist, everything. I've swapped a 3.4 in a 96-97 firebird, took a day.

Dale

iTrader: (12)

You sort of have it set, and thats what I am hoping to do with my soon swap.

To prep 3.4 as you desire, you will need to get buy a few duplicates of whats on your engine. Timing chain, (want orginal look) get oil pan, new water pump as this is the time, extra lower 1/3 intake. Extra fuel rail, load the injectors in it.

Is your engine single belt, or multipule belt?

I agree, replace all seals/gaskets EXCEPT the heads.

While apart, borrow torch and get that plug out. You will have coolent sensor in intake, yes, but the one that controls the fans should be in the head (on a 2.8).

As swap sounds that easy as one day, plan a whole weekend, take your time, make sure its all right the first time.

Project: 85 2.8 bird

The fan temp switch ins in the rear of the pass head on the 2.8. THe 3.4's do not utilize this & have a pipe plug in it. This has proved a problem for those doing this swap (although KED does provide a solution in his article). I went ahead & ran an after market fan relay & bypassed the factory setup.

FbodTrek

Hey, what were you running with the 3.4? Anyone else with the swap as well, I'm curious as to what to expect (15's? 14's?!?). Also, seeing how the motor is going to be out, what kind of Cam numbers would you recommend, the car is a daily driver and gas doesn't bother me.

FbodTrek

My belt/accessory setup is like the one in KED's picture, Will I need to use my water pump (the 2.8 one)? Oh yeah, could i use the 3.4 distributor, that much less stuff to mess with.....thanx

Project: 85 2.8 bird

3.4 has no distributor( DIS ignition ), I reused the 2.8 one.
Reuse, or buy new, 2.8 waterpump along w/the 2.8 timing cover that's being swapped over. May as well to the timing chaing thing too whille at it (remember where the dots are BEFORE taking gears & chain off)

Dale

iTrader: (12)

what was I running with the 3.4 in my truck.... loss of traction

Never took the truck to the track the whole time I owned it, it was a show truck, not a race truck.

TechSmurf

We can tack up 52/53 in the coming month.. coaching my gf's brother through the 2.8->3.4 swap. And to think, he doesn't get to take phase 2 (non-classroom) autoshop till fall

He should be picking up the long block today.

KED85

WAY EXCELLENT TO HEAR HOW MANY PEOPLE ARE KEEPING THEIR RIDES RUNNING STRONG ON THE CHEAP!
KEEP AT IT!
1/4 mile times & such.
Right now my car is the ONLY duly driver my family has.
BUT I can tell ya this,
with a 3.4 & stock stuff (you & your car define stock stuff),
one needs to increase cool outside airflow to engine. This allows one to pass people on freewyay at over 60 MPH.
A more efficent exhastusystem is necessary.
The 3.4 in power output & revs hits a wall about 5,000 rpms.
Once I make it to Phoenix (soon, two more doctor visits for family & I'm staying for that reason right now) & the headers are a reality, the 3.4 will be one realistically potent mill in the 3rd gens chassis.

PS BE AWARE ya not gonna win every race with a 3.4 under the hood.
I surprise MANY folks, but not win every stop light race.
The 3.4 swap boogie is intended to create a very strong daily driver for yourself, on the cheap.
I enjoy driving the Firebird to my 1974 Corvette, because the Firebird is such a well balanced ride.
And serious, I love the torque this mill puts out. Somedays this 3.4 power upgrade is such a treat. The ways I can leap over hills in 4th OD just stuns me. And that's with family in car & AC running, too.

Don't worry about end results power, Get car back on road, quickly & securely. DEFINETLY REPLACE T CHAIN AND make sure ya get the balancer snout repair sleeve for a measly $4!
Enjoy your project!

Again, I reused everything from the original 2.8 donor engine except I used the 3.4 injectors (NOW ya know why ya get the 3.4 mill fully dressed!).
YES the original vehicle ECM works perfect no worry on that detail!
Take your time for the attack, will be pleased.
USE the original vehicle distributor.
Search for my Distributor rebuild thread, it's easy to do!

Remember best way to do this project is to NOT reengineer anything, just swap & replace & upgrade.
BUT each swap is custom & there are NO rules on "Custom" just a way you accomplished it & it eventually works right.
AND again, no need to remove exhaust manifolds on this swap, ever. If ya remove, ya just waste a gasket.
Keep asking we'll get ya thru this.
The best reward is the smiles per miles ya tell us about!

NHRATA01

I got a stupid question...

If you were doing a 3.4 swap, and you grabbed the 3.4 out of a 4th gen, could you snag the ecm (from an OBDI year like 93 or 94) and wiring harness and just run the distributorless ignition?

Just curious...

Also KED, I thought smog-wise the rule is you are OK if you swap in a motor from a later year car, or another engine that was availible in your car in its model year. But you can't swap in a motor from an earlier year. IE it isn't illegal to swap a 93+ 3.4 into a 3rd gen, but it would be illeagal to swap a 2.8 into a 4th gen.

Dale

iTrader: (12)

nhrata01, that is what I did in my s10 truck.

To be honest, the benifits of going from mpfi to sfi is not worth it.

From TBI/carb to Sfi, partly worth it.

KED85

I "told" what I did to a very cool smog guy.
He goes, ya traded engines, ya go for smog OK
But ya kept same V6 drivetrain, but ya used a later engine, but ya didn't use the later engine induction system, but ya used later engine & put back on old original induction system.......

DON'T TELL ANYONE!!!!!


That's why I disguised my 1985 Firebird (& my 1985 S-10 Blazer carb set up) underhood to look exactly like my 1985 2.8 mill set up. To fool 99% of anyone looking. And skirt needing any smog ref costs & visits.

To be Smog legal honest, I believe I am in "Gray area", but on good side due to how car is smog tested, running very smog free clean & honestly, I "win" one for us Hot Rodders/Car Crafters, cause I'm not sure what I should have smog legal done. All I know is my personal end result, no one is wiser, thus.....

Really if ya go thru tough smog testing, this 3.4 engine, as delivered from GM to your car engine bay, is a win win situation. Ya pass smog so easy! IF ya original MPFI/ignition stuff is in great shape after swap. Use the 3.4 injectors, too & the original vehicle ECM & NO problems at all. Upgrade to new rubber diaphrams under the original vehicle fuel presure regulator, too. NO need to increase fuel pressure, just use fresh rubber diaphram.
Details!

FbodTrek

Can I use the 3.4 fuel rail!?!? My motor is coming tommorow morning, My gaskets will be delivered to the shop (every seal and gasket 40 bucks! With the rubber valve cover gskts). Things look to be slow this week at the shop, so I have an open lift and help from A very experienced Prostock guy (high 8 sec 69 Camaro!). Anyhow, I figure I'll work up the 3.4 tommorow, paint the block, accessory brackets (got the entire setup), and anything else that I need. I'll keep you posted folks.

Dale

iTrader: (12)

No, 3.4 rail will not work. You will see why when you get the engine.

Alot of the stuff we are telling you will "click" when you see things in hand with your own eyes.

FbodTrek

What kind of Cam would you suggest? I don't care about idle, I want good response and mid to high rpm power.

Dale

iTrader: (12)

then use the one thats in it. Esp if your wanting a quick change in it.

Another prefured one is the crane2030

I prefure low gunt, so I will need to change mine.

FbodTrek

Low rpm torque, or high rpm horsepower (my 2.8 has a HECK of a lot more power down low.) I just don't want the motor to fall on it's face like the 2.8 did (at around 4.5 G's). There was NO pull in higher Rpms.

KED85

As the 3.4 is delivered to ya, you'll be very pleased.
The 3.4 factory cam is the Crane 2030. Crane Cam designed the valvetrain of the 3.4.
See GM performance Parts book for confirmation.
Yeah, once ya see the two blocks side by side, you'll see many things click.
Keep it simple but you are doing a custom swap.
There is NO shame to use the 2.8 induction stuff. It works so well with a larger mill.
This 2.8 induction/ignition system is very adaptable to 3.4 engine size with no downgrade in performance.
Biggest hold back to full on 3.4 power is the stock 3rd gen F Body V6 exhaust system.

FbodTrek

My exhaust isn't stock! I'm running 2.5 through a a high flow cat and into a dual turbo muffler. Sounds super nice with the 2.8, anxious to hear it with the 3.4. I'm thinking of picking up a single dump for right before the cat, couldn't hurt I guess (for 60bux, whadda want?) If the Cam that's in there is good, I won't spend the money. I would like the mostr useable torque curve i can get (for street drags anyway). a nice lope would be sweet too.

Dale

iTrader: (12)

The 3.4 I had in my truck had very nice mid/upper rpms.

The "fall on its face" you feel is the front side of the exhuast. Manifolds mainly!

however, the redline on these engines is around 5 or 5.5 I belive?

KED85

however, the redline on these engines is around 5 or 5.5 I belive?

IF that is true (I do not know the 4th gen dash tach personally never saw one) I'd say I would attribute the rise in RPMS due to the better 4th gen "Y" pipe & the larger 4th gen factory sized exhaust pipes.
You have a very good exhaust foundation.
One doctor visit down for Wife today (one more for her to go) then I can leave town for Phoenix!

AM91Camaro_RS

you say you have 2.5" exhaust...i hope you changed to "y"-pipe too or the more commonly know as a "T"-pipe on our cars. that's where the most restriction is. lope at idle and low end torque typically don't go together. the lope comes from long duration, long duration is typically most effective in the higher rpms, that's where peak HP would be. that's how i understand it anyways. you could get a little lope and make nice low end power but not a lot of lope. for low end power, i would assume you'd go with a high lift (around .480" with 1.5 rockers) and fairly low duration (around 200-210) cam, am i right?

Dale

iTrader: (12)

Some cam information my brain can comprehend :hail: :hail: TYTY

FbodTrek

The Firebird I got the motor out of had a 2.5 inch Y pipe. Oh yeah, it LOOKS bigger, what most people don't know is that those Y pipes are shrouded. There's a 2.5 inch center tube, WRAPPED with a 2.75 or 3 inch outter tube. I was pretty surprised when I saw the guys cut the Y pipe in two......

AM91Camaro_RS

huh?? you got pictures of that? i've never seen anything like that.

Project: 85 2.8 bird

I belive he's talking about teh 3.4L y-pipe. It is of double wall construction.

AM91Camaro_RS

ohhh....ok

FbodTrek

Darndest thing I ever saw...I'd take pictures, but my digicam is fried... Anyhow, here's the lowdown on the motor Right now:
Replace every Gasket on the 3.4
Swap the 3.4 oil filter housing with the 2.8
Swap the 3.4 timing cover with the 2.8
Swap on the 2.8 accessory brackets and stuff
Swap on the 2.8 upper intake manifold
Swap on the 2.8 distributor
Swap on the 2.8 water pump....
-NOW, i assume all of these swap right on with no problem?
The motor I aquired had a serpentine belt setup (I got all the brackets and even a fresh power steering pump). My Next question is, "Will swapping on the 2.8 crank pulley and balancer be a problem?
Also, The basturds bent the flywhell on the 3.4 bringing me the motor, will the one from the 2.8 work? And, can I use my starter with the 3.4? Sorry for all the questions, but, I'm sure you understand. Thanx

Project: 85 2.8 bird

get a new 3.4 flywheel, & starters are the same, in fact, you shouldn't even have to touch it. everything else sounds good to go. The crank pulley & balancer shouldn't be a prob.

KED85

That's correct.
To make the project very simple, strip down the 3.4 to just Long Block.
Put it besides the 2.8 outta car, just start examining.
You rebuild the 3.4 ONE SIDE AT A TIME (top, then sides, then bottom, a 4 part project)
Remember NO need to remove 3.4 HEADS nor the Exhaust Manifolds.
The 3.4 PS pump is IDENTICAL to original vehicle one. I know I have a 95 3.4 PS pump in my 85 Blazer. BY USING the 1985 ORIGINAL VEHICLE PS PUMP PULLEY (swap them). The "outlet bend pipes & such" pose NO problem at all.
You got newer starter? LUCKY SCORE!
Keep your questions "simple" as then you'll need no engineering degree. Keep thinking, there is a simple solution.
When I did my original Swap Boogie, I had no coaching like I've offered to all here. And I'm an automotive idiot. You can do this bloody simple custom swap!
YES MOST DEFINETLY NEED A 3.4 flywheel.
The distributor PLUG of 3.4 mill removes very easily & just reinsert the 2.8 unit AFTER ya swapped on 2.8 intake.
ON many wires ya see & various plugs on the 3.4, serious, NO CUT THE WIRES, just wrap them up & leave in the plug. That way ya prevent a leak of any type. I especially refer to the one lone senosr plug on top of engine infront of manifold. That is a cam sensor & if ya remove it, well, don't say I didn't warn ya. I've run over 15,000 miles with that in there & no leaks.
You can safely remove the knock sensor at the engine mount area, passenge side.

Let me know if ya need more pics & such, send me an email.

Again, the hardest part is removing that plug in head passenger side, rear, under valve cover. Once that is done, you are so down hill, it's a great ride.
MAKE SURE REMOVING THAT BLOCK PLUG IS JOB ONE!

The factory exhaust pipes on most of GM rides are of double wall construction. That's why factory replacement pipes from GM do cost so much!

Keep asking we'll get ya thru it.

LT1guy

iTrader: (1)

That is due more to the heads, not the cam...running .470 lift, and thats still true, even with mild porting. We're considering a more radical porting job now.