cdoyle

Hi,

Some of you might have seen some of the work I've been doing to my 84 (92 dash installed, LED tails etc)

One of the things I've always hated about my car was that 2.8L v6, it's a piece of crap. I've always wanted to put a V8 into it, and thanks to this board, and the sticky. It gives me hope that it can be done!!

Last weekend, I bought a 91 RS with a 305 (auto). So now I think I have almost everything I need to do the swap.

Since my 84 is a carbed V6 (auto) it doesn't have a in-tank fuel pump. So I'm thinking to keep this swap as simple as possible, I should go with a carbed setup, with the V8. I'm guessing the V6 fuel pump won't work with the V8, if not what type of pump do I use??

I also think going carb would make all the wiring more simple, since I wouldn't need to even mess with a ECM. Is this right? My 84 is an Auto, so I guess I would need to keep the ECM for that wouldn't I? Not sure how that works?

So if Carb is the way to go, since I'm a total noob at this. What type of Carb do I need? (lol)

I'm going to assume if I do this, I can make all my gauges work still right? Since I did just put all that time putting that 92 Dash in it!!

I've been searching the forums, trying to find other members who done the swap. If you are reading this and done it, please post! If you have any tips or maybe some pics as you went along?

Thanks
Chris.

five7kid

iTrader: (14)

The fuel pump on your V6 is mounted on the engine. If you go with a non-computer carb for the V8, then you'll need an engine mounted V8 fuel pump. One for a carb'd '82-'87 3rd gen V8 would work.

The ECM doesn't do anything for the transmission but lock up the torque converter clutch. You can rig that up to work without the ECM (discussed often on the Transmission forum and here).

You will need to convert the engine from EFI to carb. There's a tech article linked from the thirdgen.org homepage that details that. The engine (not ECM) harness from the V8 car might make the job a little easier.

cdoyle

Thanks I'll take a look for the EFI to Carb tech article.

When you say 'engine' harness would that be the C-100 that mounts to the firewall?

Thanks for the fuel pump suggestion too, I didn't think to just go back to an older 3rd gen V8 and get a pump from them!!

five7kid

iTrader: (14)

I think that's what I mean. In all honesty, I've never looked into the factory designations.

It will have a return line on it, as does your V6. The V8 pump mounts on the passenger side, while the V6 mounts on the driver's side. As you might guess, the factory V6 fuel lines go to the driver's side, while the factory V8 lines cross over the transmission tunnel to the passenger side. I solved that by running line across the front of the crossmember over to the passenger side.

cdoyle

Cool, thanks for the tip on the fuel line.
What type of carb should I be looking for?

KrisW

iTrader: (5)

Just throwing another thought out there...

Why not run fuel injection? Simplicity? Well... I think it's pretty simple because you have the ENTIRE DONOR CAR with every wire, harness plug, nut and bolt, fuel pickup, I MEAN EVERYTHING to do the job right! If you take plenty of pictures while you take it apart, you ought to be able to put it all back into your car properly. Just remember to use a TPI or Vortec in tank pump, the TBI pump sucks.

I'm only throwing this out there because "simple" and cheap are not always walking together, hand in hand. I prefer cheap. I always seem to have more time than money!

Good luck!!

five7kid

iTrader: (14)

You can do that. You'll have the added complication of changing out the ECM. The '84 doesn't have an in-tank electric fuel pump, so you'll have to drop the tank and swap that out (probably easiest to just swap the tanks - change the pump and pick-up sock while the tank's down). While you're at it, swap out the fuel lines as well. You'll also have to run the harnessing and relays for the fuel pump.

More complicated, but EFI really is more efficient over the long haul. And, as Kris noted, since you have the complete donor car (what's wrong with it?), probably cheaper as well.

cdoyle

I thought of doing this, but wasn't sure how good the 16 year old injectors would be ect.

To swap out the ECU, how hard is that? Basically just move it over and hook it up using all the 91 harnesses ect? Is there anything else that I would need to do?

I guess my thoughts were running a carb would just be less trouble in the long wrong, but maybe I'm wrong???

The donor car is actually not in too bad a shape, something going on with the front end, shakes really bad. Think a bearing or something is out, who knows. It starts right up, and seems to idle fine, etc. I really haven't had a chance to look at it too much (it's at my parents house) but last time I was there, didn't see any oil spots or anything) I was happy that the front GFX was good! I've been looking for the 91/92 style for awhile, and most are going for $200 just for the darn part!!

I kinda wish I didn't put that 92 dash in mine yet, since I had to re-pin the C100 harness to make it work with the firewall connector. So if I use the 91 harness, I'm going to have to re-pin it back. bummer, didn't think of that when I started

five7kid

iTrader: (14)

I did a complete dash swap when I did my V6 to V8. Don't regret it.

The ECM fits up in the dash. You'll have to change the engine/ECM harness that passes through the kick panel, but that isn't a big deal.

If the only thing wrong with the '91 is a front end shake, I don't think I'd take that car apart. After all, the best answer to the question, "How do I go from a V6 to a V8?" is still, "Sell the V6 car, buy a V8 car." Ignorance and sentimental value are the only really valid reasons for doing the V6 to V8 swap. Well, maybe the desire for self-inflicted pain belongs in there, too.

cdoyle

Ya the only reason I'm doing any of this is because the 84 was the first car I ever bought, and I still have it.

I really have no interest in getting the 91 up to par, plus the 84 will be exempt from emission in 2 years, the 91 still has awhile to go!

The 91 has all the common stuff wrong with it, that I already fixed on the 84 (door hinges, interior looks bad etc). Really don't want to fix all that stuff over again.

KrisW

iTrader: (5)

You should do a full swap out, then. You won't have too much re-pinning of wires. You'll be using the engine harness completely that goes inside the LF fender and then into the car from that way along with the new ECM. You just have to look at the wiring diagrams to move a precious few wires from your old ECM connector to your new ECM.

You will be very, very happy when you are done.

five7kid

iTrader: (14)

Ummm, RF fender (passenger side).

(Are we having left/right discrimination problems these days??? )

cdoyle

LOL, Ya don't confuse me anymore then I already am

I'm hoping this summer to get started on this.

So besides replacing the old intank pump, what else should I do for maintenance since I'm taking the car apart?

KBcobra

i agree with him. imo look for a 91-92 Z28 do a complete swap. what i mean is swap whole harness (except the airbag), you got the dash, the engine (its TPI),things under the engine bay, like a/c if it didn't come with it, basically make your 84 look like a 91-92. price im not sure. lots of work but in the end worth it

cdoyle

That is my goal to make the 84 look like a 91-92.

OK, looks like the it's unanimous do the entire swap.

Looks like I know what I'll be doing next summer!
My goal is to get this car back on the road again in 2009. So I have some work to do

KrisW

iTrader: (5)

Ugghh.... DAMN those beers!!!

YOU GUYS KNOW WHAT I MEAN!

I hope you get it right! Good luck!

cdoyle

Well finally got back to doing something with this,

Yesterday, pulled the tank out of the donor car, what a pain in the butt that process is. Good grief, I couldn't believe how much trouble it was getting that out of there!

Makes really not looking forward to doing it again, on the 84.

Since I have it out, going to change out the fuel pump, since I never want to drop a tank after I have it back up.

It was mentioned earlier, that I should get a TPI fuel pump, instead of what the 91 originally came with? What year/model fbody did these come on?

KrisW

iTrader: (5)

That pump was on the 85-92 vin code F and 8 cars. You can also get the pump from the 89 TTA at the auto parts store for 5 bucks more and it's better still.

cdoyle

OK, do I just ask for a fuel pump from an 89 TTA.

Where do most of you get replacement parts?
I've always had bad luck with the auto parts places, stuff always seems to not last. For this project, I want to make sure I get something that takes another 20 years to wear out.

cdoyle

What brand pumps do you guys recommend?
The auto part stores have all different types it seems, depending on which one you go to.

I just don't want to ever have to do this job again

cdoyle

Does it matter what brand I get?

http://www.partsamerica.com/ProductL...hfor=Fuel+Pump

when it says 'wiring harness should be replaced'

Are they talking about the harness that goes from the pump to the connector on the car?

cdoyle

Anyone?

ssj2link

iTrader: (15)

go with a walbro pump its a good one and if u mod the motor it can handle lots of HORSES!

cdoyle

Thanks, I'll look into that pump.
Are they available in most auto parts stores?

Have another question related to this swap.
Been reading up that the engine mounts are in different locations between the V6 and the V8.

Are the engine mounts themselves the same? Or do I need to purchase V8 mounts? How many are there?

Does anyone have any pics of where they mount?

ssj2link

iTrader: (15)

yeah and u need v8 mounts and they are in a different spot. u gotta drop the arms to get to them. there are 2, 1 per side

cdoyle

I'm finally getting back to working on this car, I ended up selling that donor car.

I figure if I'm going to go through all the effort of doing this swap. I might as well get a Z28 donor car with a 350.

So I want a TPI donor car right? What years did the cars start using TPI? Is there a certain range of years that are better? I've been trying to find a 91-92 but not having much luck so far.

On my 84, I have the 6 out and while I'm looking for a donor car I'm cleaning up the engine bay and going to paint it a glossy black.

I still need to move those engine mounts too.

five7kid

iTrader: (14)

The '87 TPI 350 started in 1987.

cdoyle

Thanks, now just have to find a donor for sale.

cdoyle

wow, this is driving me insane.
I've been looking all around my area on craigslist looking for a Z28 (with the 350) to buy for a donor car. There hasn't been any listed in a long time, or if they are listed, the car is too nice to use for a donor!!!

I'm either going to have to settle for a 305, or widen my scope.

I want to make this swap as easy as possible so I really just want to swap everything off the donor into mine, like discussed earlier in this thread. I would like to get a TPI car too.

so I've been wondering how about trans ams? I'm guessing almost everything is the same, maybe the PIN on the main harnesses will need to be moved around some but I would have to do that anyways.

What years did the Firebirds go to TPI, and is there any reason not to go this route and instead try and keep looking for Z28?

I would really like to get the engine installed by the end of summer, and I'm running out of time!

cdoyle

So would a Trans Am be OK to use for a Donor?
Are the main harnesses that goes into the firewall and also the computer the same shape as the Camaro harness?

cdoyle

OK
Found an 87 Iroc in my area, talked to the guy and he said it was originally a 305 TPI, but it's been swapped to a 350 TPI.

I haven't looked at the car yet, but just wondering what I should look for?
To confirm it's a 350, I've read on the forum there are numbers on the engine itself that I could look up to verify this. Where are these numbers located? are they easy to get too, and read?

On a 305TPI to 350TPI swap, is there any warning signs I should look for (besides the car not running etc). I'm hoping all the wiring etc is intact, because I'll want to use all that in my car.

To swap to a 350, he would have to swap out the computer right, if he didn't it wouldn't run would it?

Just want to make sure I know everything before going over to see it.

cdoyle

I cannot believe how difficult it's been trying to find someone local selling a Z with the 5.7L. If I do happen to find one, they are always 5k or more.

Don't really want to spend 5k on a donor car!!!

Anyone have any other areas to look for cars? I've been mostly looking at craigslist, and the papers.

I would like to find a car that either been hit in the side or something. Engine and tranny still good, but the car body is crap.

KrisW

iTrader: (5)

I guess I don't see why you are specifically looking for a 350 car if you are on a budget.

Any TPI car will do, Camaro or Firebird for what you need. You can swap a 350 (or larger) in under all the 305 TPI stuff with no problems. You'll only need a 350 ECM chip and some injectors to finish it up.

85-86 TPI cars are non roller cam, I think, and the flywheel is different. 87-92 is your best bet for the swap. The ECM is better in those years too.

Some budget guys are happier to get the 305 TPI car for parts because the cylinder heads are more desirable. They are wonderful budget heads to use on a 350 swap.

cdoyle

It's not so much a budget issue, it's more that a $5k+ car, isn't really a donor car anymore. I really don't want to kill a perfectly good car, for my swap.

It just seems the price of these cars have went up a lot over the past few years. I used to see Z28's all the time for sale for 2K and below, but now it's impossible.

Not sure why they've went up so much.
I'll just keep searching for a donor to get everything off of, I was just hoping to get this done this summer.