BigNorm

I'm currently researching building a 3.4L out of a 93-95 F body.
I would like to use 2000+ FWD aluminum heads and pistons to drop the CR to usable levels with pump gas.

My main question pertains to the electronics in this build. The vehicle I have currently has a carb'd 2.8L in it and I was wondering if anybody could help me with finding information on doing a carb'd to Fuel injection swap. Is running TBI on this motor possible? I've heard with the newer heads that the older intakes won't bolt on. I also think that TBI would be shooting myself in the foot with the better systems available. Anyway. Any help you could give would be greatly appreciated. NORM

AM91Camaro_RS

welcome to the boards!

the 3.4 with aluminum heads should run pretty good. the thing that's the biggest problem right now is that the 3400 (FWD 3.4) base intake manifold has clearance issues with the distributor. they don't have that problem on the FWD cars because they run coil packs (or DIS ignition). Have you checked into trying to go carb'd (like using a 4bbl 390 cfm holley or something rather than a stock 2bbl)? this wouldn't be terribly simple either because i'm not aware of a manifold for that, that would fit the alum. heads but, going FI, you'll have lots of wiring to mess with installing. So, any route you take isn't going to be simple. The alum. heads through a monkey wrench into everything for us guys (and gals). But, if you get a complete setup that'll run, it should run good!

The_Raven

Using the genIII heads will actually RAISE the SCR, not lower it. The genIII heads use a 28cc combustion chamber as opposed to the 58cc of the iron heads.

Using the genIII heads is well worth it though.

I did something very simililar to what you propose, but I started with a 2.8L block.

You'll be better off starting with the 3.4 block, since it has a provision for a crank position sensor that that the DIS needs.

I'll recommend using an ECM (and wiring harness) from something like a Cavalier or Beretta though, as it will make the swap much simpler. The ONLY thing you are giving up going this route as opposed to the F-body 3.4 PCM is the SFI, but even the SFI PCM reverts back to batch fire at around 3000 RPM anyway.

Check out

BigNorm

Thanx for the help guys. I don't think clearance will be an issue because this will be bolting into a jeep cherokee. If there is one I'm not afraid to cut sheet metal. I have alot to learn about FI still. You guys are confirming what I've heard from different sources. That different computers will work with the same sensors.

I want to do this motor swap for a few reasons: it seems cool as hell and If everything works right then I'll be getting close to V8 power with small motor mileage.

I understand that I'll have to go with gen 3 pistons along with the swap to keep the CR down.

Thanx for the Cavalier/Barretta advice too. I've heard these engines can be found in some vans as well. Are there any advantages/disadvantages to sourcing one there?

Thank you for your help. NORM

The_Raven

When I mentioned the Cav Beretta, I was meaning controls only, not the engine itself, though the '94 to '94 'Retta did get the 3100.

Anyway, pretty much all the 3400s around from '96 to present will do the same job for you, there are some VERY minor differences, the most major being the cam sync ring on the cam itself, it went through some chages, none of which will effect the way it runs, especially if you do use the MPFI ECM from the Cav/'Retta.
A lot of swappers do use the U-van 3400s since they seem to be plentful and cheap.

AM91Camaro_RS

the clearance issues are not with the firewall or any sheetmetal you can simply cut out...it is that the distributor hits the intake manifold and from what i have heard, you would have to nearly cut the #6 runner clear out to get the dist. to clear.

The_Raven

QFT!

I'll be working on a way around this, I may just end up making a whole new intake manifold, but for other reasons as well.

BigNorm

This is what I'm basing my build off of. Someone has done this already:
94camaro has been helping me out quite a bit as well from West coast F bodies. Here's the post I have there so far:
http://forums.wcfbs.org/wcfb//Threads.asp?ID=3249

Aparantly there's a few different intakes that can be used. Thanx for the help.

BigNorm

Would flipping the upper intake 180* create clearance for the distributor? I don't have one in front of me right now so I can't know for sure but I'm reading that some had to flip the upper intake around for "clearance" issues.

AM91Camaro_RS

the water neck on the back of the engine could be a little tough to deal with, then... oh, and pointed at the dist.

BigNorm

Ummm. I believe the correct phrase was the UPPER INTAKE. Jeese!

BigNorm

That would be the thingy on top of the lower intake. The part with the water neck you refered to.

AM91Camaro_RS

oops....sorry. i read that too fast. the upper isn't where the problem is. but yes, technically it is turned around but that's just so that the TB points to the front of the car rather than the firewall.

BigNorm

Sorry for shooting off at the mouth so quick. I don't want to cause any bad feelings here.

The_Raven

Yes, 94camaro is quite helpful, but he also did this swap IN a '94 Camaro, so the electronics were already working, he just did the top end swap (essentially). He's also on www.60degreev6.com.

The problem lies in transfering the PCM and wiring into a vehicle that never had that system. This is why I am suggesting the use of a different ECM and harness.

The intake, both upper and lower, can be turned around, which needs to be done anyway for a (front) longitudily mounted application, so that the T-stat housing is pointing forward, and the TB. The problem as stated is not JUST the upper, but also the lower, the #6 runner in the LIM gets in the way.

BTW, you can look at any 3400 equipped vehicle for donor parts, they are all essentially the same, as far as flow, and fitment is concerned.

BigNorm

Got it. I guess I'll be searching for Berretta/cavalier for electronics then.

I'm going to embarass myself now:

What's a PCM?

While we're at it what's an ECM?

This will be my orientation to Fuel Injection as well as up to now all my vehicles I've built have had carb's installed. Thanx and I thank you for your patience.

The_Raven

PCM = Powertrain Control Module

ECM = Engine Control Module

Both do essentially the same thing, but the PCM is on newer vehicles and generally controls the tranny as well.
Some people will interchange the terms.

BigNorm

Thank you so much for your help. I should have known ECM. That'll work great since my application has a standard tranny. I think it's a T5.

BigNorm

Does anybody have experience making they're own intake manifolds? What kind of sheet metal would work best? flanges? If anyone could point me in the direction of someone who's done this I'd be greatfull. It doesn't have to be a 2.8 either I just want to know all that's involved. The 390 4V carb has me intrigued. Thanx again.

Aggp18

You should talk to Alan AM91Camaro_RS, he has built the most efficient intake to my knowledge. Nice guy too, always answered my PM's with great detail.

BigNorm

I didn't know that Edlebrock made an intake for the 2.8 at the time I posted this. I'll probably just go with the 3.4L motor with the 2.8 carb'd intake that edlebrock makes. Here's the part's I'm talking about:

http://www.60degreev6.com/modules.ph...rtid=22&page=1
Scroll to the bottom to see the PN's. I clicked and drug the pn's and checked them through summit. By the looks of the 4v adapter it bolts onto the top of the 2v intake. I may buy that first just for fun and see how the 4v works on the stock 2.8 I'm sure I'll have to jet it down real fine so I won't run rich. In the end I want the 3.4L. I'll work the heads myself. (I've never done this before so I'll be carefull), get the edlebrock stuff and the 390cfm holley. It's not the newer heads but it's as good as it gets for a carb'd guy.

CHVYPWR

Here's what I did with my '85 Cherokee. A MPFI from an '86 F-body.

BigNorm

Damn that looks sweet. How was the difference in performance from the carb'd 2.8?
Also do you have links to more pics? What harness did you use? Computer? Where did you bolt the computer? What problems did you run into? lol. I have lots of questions. I'd appreciate any help you could offer.

CHVYPWR

Only pic I have right now, more to come next week when I haul it from my dads place to mine for a trans swap.
Hard to tell what the performance truely is yet, the trans was bad when I did the swap and I havn't replaced the trans yet (slipping and sluggish on take off). It ran enough to test drive to work out the bugs though. Initial results were way better throttle response, got up to speed way better than the carb'd one (obviously), and overall better street manners. I used the entire engine, injection, harness, and computer from the Camaro. Heck, even the Camaro electric fan is mounted up and functional! I mounted the computer in the Jeeps glove box. One problem that I ran into was a fuel starvation issue at 45+mph. The injection requiers a larger diameter fuel line to supply enough flow.I replaced the entire fuel line and used a fuel tank with pump and sender out of a 4.0 powered '91 XJ to feed fuel to the 2.8 injection. The Camaro wiring took some time to sort and weed out the un-needed systems, keeping only what was needed to run the engine. I used wiring diagrams from Jeep and Camaro Chiltons manuals to find what, and where to connect. A lot of the stuff was simple to find since the 2.8 Jeeps used a lot of the GM wiring for the ignition and starting circuits. Need any more help, feel free to ask

BigNorm

Thank you. I have a standard trans so I believe that'll make one part easier. I was thinking of swapping to the 4.0 tank as well.