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found a 3.1 and a 3.4. double checking what ill need by logical1
Started on: 03-27-2014 06:42 PM
Replies: 18 (291 views)
Last post by: BillS on 03-31-2014 12:19 PM
logical1
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Report this Post03-27-2014 06:42 PM Click Here to See the Profile for logical1Send a Private Message to logical1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok found 91 transport with a 3.1 in it. And a 3.4 out of a camero both hav around 120k and have the same price so im Looking to see what ill need, So far I hear olds omega intake and distributor to make both work on carbs. I see ill need a fiero timing cover and im thinking is it like the 3.4 swap where i will need the 88 2.6 oil pan since they conect. Or is my 88 2.5 correct for the 3.1 swap? Also if I need those too from the fiero v6 im thinking I might aswell buy the fiero flywheel, and do 3.4. Since im going carb are these 3 things I need to drop in as a direct bolt on replacement?
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jscott1
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Report this Post03-27-2014 10:47 PM Click Here to See the Profile for jscott1Send a Private Message to jscott1Edit/Delete MessageReply w/QuoteDirect Link to This Post
I would recommend to not even look at the 3.1 from the Transport. It's actually a downgrade from the Fiero 2.8. The 3.4 bolts right up to everything except relocating the starter to the other side. Rodneydickman. com sells a jig to help you drill the new holes.

Don't know why you are going carb though, the Fiero ECM will run the 3.4 just fine.
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logical1
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Report this Post03-27-2014 11:43 PM Click Here to See the Profile for logical1Send a Private Message to logical1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Well I have the 88 duke fiero. I thought I needed ecm harness. Bc ive seen ppl advertise that they make the 3.4 harness. Plus ive seen something saying I need the fiero v6 flex plate flywheel and timing cover. Seeing as I have a duke im under the impression that ill have to find all of that
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Csjag
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Report this Post03-28-2014 05:41 AM Click Here to See the Profile for CsjagClick Here to Email CsjagSend a Private Message to CsjagEdit/Delete MessageReply w/QuoteDirect Link to This Post
Something tells me you are asking for trouble with a carb on a Fiero engine. I would be concerned about issues with a backfire thru the carb causing an engine fire and a burnt Fiero.
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olejoedad
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Report this Post03-28-2014 05:55 AM Click Here to See the Profile for olejoedadClick Here to Email olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Stay with the fuel injection. Its easier, less expensive initially and will deliver better performance and fuel mileage.
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lou_dias
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Report this Post03-28-2014 07:04 AM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post
If the 3.1 came with the engine harness, you can find a '7730 ECM and plug-n-play almost...
It's a short list of wires that you'd pass onto the Fiero C500 and C203 connectors to make it work.
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lou_dias
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Report this Post03-28-2014 07:11 AM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post
If the 3.1 came with the engine harness, you can find a '7730 ECM and plug-n-play almost...
It's a short list of wires that you'd pass onto the Fiero C500 and C203 connectors to make it work.
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logical1
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Report this Post03-28-2014 11:38 AM Click Here to See the Profile for logical1Send a Private Message to logical1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Neither engine comes with engine harness. Plus carb is easier for me to tune. Ive had mack fires on my old 2.5 and inwas never anything serious. Honestly im really nust done with this while wiring headache. The 3.1 or 3. 4 will suffice untill my buddy finishes his 3800sc build. Once he does his successfully ill pay him to do mines. Im just not interested in running wires or troubleshooting blimp mode getting ecm programmed. I want my car back on the road. Ill get a spare cradle and at that point I can have fun with the swap. Right now im just going for a quick solution. Seems like 3.1 will be he quickest but I can seem to find much info on the carb swap. I dont care about gas miliage. right now its about getting back on the road
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timinator
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Report this Post03-28-2014 01:00 PM Click Here to See the Profile for timinatorClick Here to Email timinatorSend a Private Message to timinatorEdit/Delete MessageReply w/QuoteDirect Link to This Post
Edelbrock makes a carb manifold for 60* v6 iron head. Sometimes find them reasonably on ebay. I'd go 3.4 for extra cubes! Especially if carbing.

[This message has been edited by timinator (edited 03-28-2014).]

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timinator
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Report this Post03-28-2014 01:03 PM Click Here to See the Profile for timinatorClick Here to Email timinatorSend a Private Message to timinatorEdit/Delete MessageReply w/QuoteDirect Link to This Post

timinator

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Edelbrock makes a manifold for 60* v6. Sometimes find them reasonably on ebay. I'd go 3.4 for extra cubes! Especially if carbing.
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KurtAKX
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Report this Post03-28-2014 01:11 PM Click Here to See the Profile for KurtAKXSend a Private Message to KurtAKXEdit/Delete MessageReply w/QuoteDirect Link to This Post
...except the 3.4 requires re-drilling starter holes.
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logical1
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Report this Post03-28-2014 01:18 PM Click Here to See the Profile for logical1Send a Private Message to logical1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Yes redrilling is a little scary.. but does the 3.1 require the same flywheel flex plate and timing cover as the 3.4. Ya know I dont have a 2.8 so finding those parts are an additional cost unless ofcourse you need them for either swap
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Slowbuild
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Report this Post03-28-2014 04:00 PM Click Here to See the Profile for SlowbuildSend a Private Message to SlowbuildEdit/Delete MessageReply w/QuoteDirect Link to This Post
Ignore the comments on the carb.

I have done a 3.4 swap, and it required code changes (retune) to run properly. I didn't mind because I went turbo thereafter.

A good carb and a good intake will get rid of the crappy 2.8 manifold restrictions. Continue to run the computer and sensors for the spark only.


Chay
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logical1
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Report this Post03-28-2014 05:55 PM Click Here to See the Profile for logical1Send a Private Message to logical1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Yea I figured.. a lot of ppl that suggest it either never had to do it, or done so much tunning amd reprogramming that they dont realize how much of a set back tuning of an ecm is.. are there any step by step tuts or builds where ppl show how they seup thier carb systems? Seems like ppl jus bypass my questions and go straight into trying to convert me slash persuade me into efi then I have tp explain myself and reasoning all the while bypassing my initial questions.. I think out of all the responses like a few ppl actually responded the rest were persuasional opinions.soooooo any tuts or builds on carb setups
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Raydar
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Report this Post03-29-2014 12:12 PM Click Here to See the Profile for RaydarClick Here to Email RaydarSend a Private Message to RaydarEdit/Delete MessageReply w/QuoteDirect Link to This Post
You're going to need the Edelbrock intake. The "recommendeded" carb is probably a 390 CFM edelbrock or Carter. IF you can find one.
I THINK the Edelbrock is available with a 4 barrel base plate.

Since you're chucking the computer, you're going to need an old (early 80s) V6 distributor. Probably from an S10. Those were the only ones that had a chance of being non-computer-controlled. You might be able to find an aftermarket distributor, but I know nothing about those.

If you have a manual tranny, you're going to need a zero balanced (aka neutrally balanced) flywheel. That could be from an 88 V6 Fiero, or from any manual tranny 3.1 FWD car. (91 Cavalier, etc.) Either engine - 3.1 or 3.4 - will require the same flywheel.
If you have an automatic, the 3.1 flexplate will be fine. I think (but I'm not sure) the Camaro flexplate is too big. A 3.1 flexplate will work.

You will likely need the Fiero timing cover and oil pan. The design changed in 87. You will need to get both of the same vintage. (i.e., an 87/88 pan will not work with an 85/86 timing cover.)

You will need Fiero exhaust manifolds and crossover. It MAY bolt to your stock exhaust, before the cat, or it may not. If not, you'll need a V6 exhaust system, too. Or at least a V6 "cheater pipe" to replace the cat.

You will need the Fiero alternator bracket, dog bone bracket, and dog bone.
You will need an 88 V6 alternator. (The 88 Duke alternator has the mounting bosses in different places. It won't bolt up to the V6 bracket.)

I'm assuming that you are not using A/C. If you do, you will need the brackets for that. The V6 compressor and lines are different from the Duke.
I don't know how to retrofit the Duke compressor to the V6.
You will need the Fiero V6 pulleys and belt.

You will need to drill the starter pad if you use the 3.4.

You're going to have to figure out how to interface your wiring (charging system, gauges, etc.) without the computer.

You will need to fabricate fuel lines to the carb. Don't know about the return line. Depends on what sort of fuel pressure regulator you run.
You will need to fabricate heater hoses, from the engine to the hardlines.

I won't sugar coat this...
I have done several swaps over the years.
One was a V6 in place of a Duke in an 88 coupe.
Compared to what you're trying to do, the V6 EFI swap was a cakewalk. It was all plug and play. ZERO fabrication.
If you can find a Fiero dropout, with ECM and harness, you're way ahead of the game.
The 87 V6 addressed the oiling problem. The 88 became internally balanced. Every bit as good as the 3.1 and 3.4.

But now you have enough info to get you started, either way.
Good luck.
------------------
Raydar
88 Formula IMSA Fastback. 4.9, NVG T550

Praise the Lowered!

[This message has been edited by Raydar (edited 03-29-2014).]

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logical1
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Report this Post03-29-2014 03:56 PM Click Here to See the Profile for logical1Send a Private Message to logical1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Wowzers... well yea its a lot of fab'n. I found 2 local shopa that will swap motors. Im going to check them out on monday and go from there. I know 2.8 is a direct drop and plug in but the whole point of a motor swap is suppose to be a noticeable increase. Whike im sure the 2.8 will be a notable increase im looking to really step my game up on the swap. Since most likely my buddy shop and our limited knowledge of swaps peobley will rewult in my fiero in 100s of pieces on his shop floor and at that point will cost me moee to deal with. I figure approaching both of the shops with a budget of between 2k-3k for Any swap 3.4 or better. And at that price ofcourse ill require that 3.4 has build sheet and is fuel injected. I know its over priced if im forced to spend that amount when it could get me a 3800sc , but this is where my lack of expierence makes me have to pay. Hell hopefully 1 has resources to get a 4.9 which is still me overpaying but I just hope it will get me something respectable. If not idk what ill do.. probly will buy parts for the 3.4 swap reguardless bc ppl have givin me deals I cant refuse n back to the deawing board

[This message has been edited by logical1 (edited 03-29-2014).]

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Raydar
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Report this Post03-29-2014 09:37 PM Click Here to See the Profile for RaydarClick Here to Email RaydarSend a Private Message to RaydarEdit/Delete MessageReply w/QuoteDirect Link to This Post
Really... sourcing all the accessories, piecemeal, is going to be the most time consuming part.
I had a complete parts/donor car when I did my swap, and I still had to buy stuff.

Or, do the best of both worlds...
Buy a blown up 2.8 dropout, that still has the harness and all the accessories, and move all the accessories to the 3.4.
You'll want an 88 donor, since it will have the neutrally balanced flywheel or flexplate, and the CS alternator.
If you're not too particular about cleaning and repainting parts, you could do the entire swap in a weekend or two.
(If you decide to go this route, I can tell you what to keep from the donor. I'm sure others can too.)

You'll have to remove your fuel pump and install a higher pressure pump for any engine other than another Duke, or a carbed install.
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logical1
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Report this Post03-29-2014 10:22 PM Click Here to See the Profile for logical1Send a Private Message to logical1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Well I dont think ill be doing anything. At this point im planning on paying a shop to do it. Unless they give me a crazy number that I refuse to pay for something so remedial.. ill know by mon worst case senerio Idk after hearing about having to source all accessories and a timing cover I may jus go with the carb 4.9 that seems less. Idk 3.1 and 3.4 was suggested i mean yeah if i had a v6 to start with , but i have a 88duke. Im guessing jus like most ppl they try to convince you of things they never tried. After hearing from u and other experienced ppl I may jus buy motor mounts and carb 4.9 atleast that way only thing ill have to fab is the ac bracket.. this swap shhht is so much unexplained info and pressure from members who dont know wat the fck they are tlking bout. I was so convinced of 3.4 or 3.1 only to hear from experience how much shht im really getting into for such a small gain. The same fuel line fabs will be needed but less stuff to track just getting the 4.9 and slaping a carb on it. So im going back to the drawing board untill monday.

[This message has been edited by logical1 (edited 03-29-2014).]

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BillS
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Report this Post03-31-2014 12:19 PM Click Here to See the Profile for BillSClick Here to Email BillSSend a Private Message to BillSEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Slowbuild:

A good carb and a good intake will get rid of the crappy 2.8 manifold restrictions. Continue to run the computer and sensors for the spark only.


Chay


Well of course there is nothing wrong with the stock intake for a stock engine - the restriction would only be important if he were to go for more than stock power.

And if he used a 3.4 from a Camaro, he could always just use the 3.4 intake which lacks those restrictions.

I'd think just picking up a stock 2.8 Fiero motor and computer/harness would do the trick and be cheapest (you can always stick a 3.1 crank and pistons into that if you were to rebuild it)
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