I've been lurkin these forums for several years reading about the 4.9 V8 installations on Fieros. I'm looking to pre-plan my own installation of a 4.9 in a Fiero GT. I want to purchase everything before I get into the swap, so I can finish it in a short time span and not have the project stagnated by looking for some "unkown" needed items that come up missing in the middle of a swap. This may be a good list to compile for anyone who is looking into this project. I am just wanting to clarify everything and have all the sources I need. The list I see so far, with some questions are as follows
Cadillac 4.9 from preferrible a 91 Deville (what other years are acceptable/preferrible) I'll be getting the complete car.
Swap will use the cadillac 4 speed auto (which is preferred, the plain 4 speed overdrive or the electronic overdrive 4 speed 60E)
4.9 will run the fuel injection. What will be needed from the doner car besides the complete engine wiring harness and Computer.
Axles (What works for driver and passenger side, Pontiac 6000 for one side? and ????? for the other)
Modficaiton of the wiring harness for the cadillac to work with the Fiero (?? link for detailed instructions) I know you can buy one, but I want to know my option in modifiying the cadillac to the fiero. What exactly cant be used on the fiero when setting up this motor.
What about the usage of the 4.9 acessories in comparison to the Fiero acessories (Alternator, AC, Gages, etc)
Specifil serpetine belt size and pulley configuration (any pictures) including belt tensioner.
Passkey issue (module from Fieroaddiction, ebay?)
Engine mounts (buy prefabs or modify existing cads) clearance issues/ I'm experience in welding and metal fab from my Pro Street projects.
Cooling issues,(from what Ive read, everthing cooling the fiero V6 will cool the Cadillac 4.9
Can a fiero with a manual be retrofitted with the 4.9 Cad/Auto setup?

I'm comfortable with the mechanical work involving pulling the cradle, removing the Fiero V6 and installing the 4.9, along with any mechanical repairs for the engine/transmission. The big inexperience i have Is with all the sensors and computer mods for using the 4.9 fuel injection. I am experinced in computers, but never used one in programming and configuring an ECU.

I'm looking at the 4.9 enginer/ trans from the doner car becuase I thing this would be the best setup, manuals are fun but I prefer the ease of the auto with the possibility of a good shift kit installed.
I also want to know if the Cad computer has the optons for performance programming such as the Hyperchip and other products available.
I am searching thru past post to collect all info, but I am sure there have been improvements over the years in this project and I want to get the latest info and not rely on old post to setup this job. Thanks.

PS. I see the 4.9 swap not as costly as the 3800 SC swap, as far as performance. Any opinions?

Welcome to the forum.The search function fill answer alot of your questions.

Welcome to the Forum. Glad you stopped lurking and started posting. This is a good post to start with.

As far as the axle set up goes, the Pontiac 6000 is the axle you want, and the other one is from a manual Fiero, however, some are now saying that that set up might slip out so there are people using half of the manual shaft and mating with a transaxle from a 94 Pontiac Transport. When doing a search on this item, you might want to see what problems people are having, because some are still saying the manual axle is safe and the way to go.

What year gt is it? That will help to answer a few questions.

If you're comfortable welding, then you can make your own mounts. They are not hard to do, and one method is to use a mount from the V6 and some angle iron. This was the way I went, and it looks like it will work fine.

If you are getting the complete car, that's a good way to go. It gives you a few options, like the Cruis Control module could be used if yours is bad. You will probably want a short section of the coolant hose to tie into. etc...

Use the 4T60E. You will want the overdrive.

You can make your own harness. Many have and I am working on mine as we speak. Having said you can, I wil also say that if you cound buy one it might be worth it. IT IS A PAIN!!! I am getting pretty sick of mine, but I am really cleaning it up and routing things the way I want them, and will be glad I did it when I am done, but this is the part that will take a while.

You V6 Radiator will be big enough to keep it cool.

Some will say to add an oil cooler and a better trans cooler. Some don't. That being said, if you have the funds, everything lasts longer and runs better if it's cooler, so I would if you can.

Passkey can be deleted with computer chip reprogramming. Aaronrus on here can doing you chip for you and he gives you options that are good for this engine. Contact him about your chip. Good guy to deal with. Anything you can get from Fieroaddiction is good as well. He is very knowledgable about these swaps, but I don't think he's on here anymore.

And lastly, a 5 speed can be retrofitted. Mine was a 5 speed and I'm going with the 4T60E. You will need the whole auto set up from a fiero, so far as the steering column, and the shifter, and cables, and all of that stuff. I also added an Auto radiator so I have the cooling lines, but I might go with an independant system after a while.

So get to searching, it's all in here somewhere. I have more info, but I'm not on here a lot, but will help if I can. Pm me as you need more info.

Darren

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Options for 4.9 performance are pretty limited.

Re-ground cam
Port work
Stronger springs
chip programing - Superchip from Aaronrus here on the forum
and the normal "Hot rodding" techniques

Sounds like you are finding what you need pretty well. If you have specific questions juat ask. There are plenty of 4.9 guys here that are willing to help.

EDIT: Probably the most helpful link that can be provided on this subject.
http://www.fieroaddiction.com/
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84 SE auto. - a fun original
85 SE V6 4 speed - stock, fully loaded - daily driver
85 GT 4 speed - build thread
88 Coupe 5 speed - runs and drives, needs work, patiently waiting for its turn.

[This message has been edited by Fieroseverywhere (edited 11-11-2007).]

Talk to Aaronrus for the chip. Deletes passkey (otherwise you need a module).

Only need the motor, tansmission, ECM and wiring harnes between them.

Performance is limited even with spending some good coin. If this is your main goal, go with something else - the 4.9 is fun to drive, but it is NOT a 1/4 mile car - it is handicapped in the upper rpm's. A buddy usually does really well with his (stock) 4.9 in the autocross (usually in the top, if not 1st in his class).

wiring is nothing, see my post here: //www.fiero.nl/forum/Forum2/HTML/079246.html it contains all you need to know. GET diagrams for your car and the Caddy

motor does not matter, but if you use Aaronrus's chip, you have to wire it as a Seville if you go with his 'Superchip' code, otherwise it gets wired as a Deville (YES, they are different).

use the Caddy acessories (alternator, starter, etc)

if your car has a/c, the ECM has to be bypassed (search for the 4.9 a/c thread) and the a/c run manually.

tensioner, my method: //www.fiero.nl/forum/A...050818-2-052483.html - most of the time I can use a 79.5" belt.

THERE will always be something that you will need from the parts store (fuel lines for example - depends how you run them will determine the length you need).

DO NOT CUT THE WIRES TILL YOU ARE SURE, and then at the max length you can get from them - you can cut them when you are working on that wire. LABEL all wires that you remove from both motors (you will reuse the Fiero's C203 and C500 plugs). When it come to connecting the C500 wires up, just put them to the same spot they came from (ie: 2.8 starter wire goes to the 4.9 starter, etc). Wiring is not hard if you prepare properly for it (label each sensor) - just time consuming.

quote Originally posted by Mickey_Moose: Talk to Aaronrus for the chip. Deletes passkey (otherwise you need a module). motor does not matter, but if you use Aaronrus's chip, you have to wire it as a Seville if you go with his 'Superchip' code, otherwise it gets wired as a Deville (YES, they are different).

Just to add to this thread, i can do the superchips/fastchips reprogramming for both the deville and seville/eldorado setups now.

email me directly at stickpony@gmail.com for more info

im wanting to try this swap to but i want to keep the auto thats alredy in the car i have my resons for wanting to do so is it even an option

quote Originally posted by zetabird: im wanting to try this swap to but i want to keep the auto thats alredy in the car i have my resons for wanting to do so is it even an option

Its deffinately an option. You even use the stock caddy flexplate. You wont get very good gas mileage and the 3 speed auto will only hold up so long. But yes, it is an option. The easiest tranny option there is.

quote Originally posted by zetabird: im wanting to try this swap to but i want to keep the auto thats alredy in the car i have my resons for wanting to do so is it even an option

If you are talking about keeping the 3 speed, yes it would be an option, but you would have to figure out how to get the TCC to work on the 3 speed with the 4.9 ECM (the 4.9 ECM is designed to control an electric 4 speed transmission 4T60E vs the Fiero's TH125C).

My 2.8 auto car revs fairly high at highway speed to the point that it would be unacceptable with the 4.9 - the 4.9 drains the gas tank above 3000 rpm fairly quick - there is a good difference of about 200 miles between driving above 3000rpm and below 3000. I personally can't see any good reason for staying with the 3 speed (other than less work - and I am not sure about that since you have to figure out the TCC circuit, as I don't think it's been done) - but it's your call.

Tim

Good call. I forgot about the TCC part. I know a couple that have used it but I believe both used a 7730 ECM also. Don't know anything about using that ECM with a 4.9 so I can't be any help there.

Thanks for the info everyone, I know the 4.9 will be limited in RPMs and makes its HP n the low RPM range, but if I can make the mods to get it up to 5K in the power band, thats good enough for me. Who has had experience with the cam regrind? I know the issues of coil bind due to high lift cams, but a change in rocker arm ration may help in the valve lift dept. The Allante Intake setup is always an option as well, but that would take additional changes in the PCM area.

The 4.9 mated to a 3 speed auto is not going to be a very satisfying ride in my opinion. I didn't like mine mated to the 4T60e auto, so I went to the F40/6-speed manual.

quote Originally posted by jscott1: The 4.9 mated to a 3 speed auto is not going to be a very satisfying ride in my opinion. I didn't like mine mated to the 4T60e auto, so I went to the F40/6-speed manual.

What kind of MGP you getting with that?

quote Originally posted by jscott1: The 4.9 mated to a 3 speed auto is not going to be a very satisfying ride in my opinion. I didn't like mine mated to the 4T60e auto, so I went to the F40/6-speed manual.

...uhhh, details...or am I going to have to come over there...

quote Originally posted by smb1691: Thanks for the info everyone, I know the 4.9 will be limited in RPMs and makes its HP n the low RPM range, but if I can make the mods to get it up to 5K in the power band, thats good enough for me. Who has had experience with the cam regrind?

As for cams - Delta cams does 4.9 grinds, they have a drop in one as well as some that require new valve springs and arms. You can also check Bud's Outback for some performance 4.9's as well. The biggest problem with the 4.9 is lack of air, however if you used some sort of forced air induction, then you can improve on that. PBJ indicated at on time that only 3lbs of boost was a big improvement and he did this on a stock engine - only did the extra engine work when he went with more boost. If you do a search for his '4.9 turbo build' thread, all the info is there.

The 7730 ECM requires you to use a throttle body with an IAC valve vs the IAC motor that the 4.9 now uses. I have read something at one point in time about Rockcraw; meantioning something about the Chevy 454 throttle body will fit the 4.9...something to consider if this uses an IAC valve. Other than that, the 7730 is a direct plug in. I think you need to use the 305 base code in the ECM for it to work correctly, then it's just a matter of tuning it (which most shops should be able to do as it is the more popular ECM). (edit) You will also need to add a knock sensor as well with the 7730.

[This message has been edited by Mickey_Moose (edited 11-17-2007).]

quote Originally posted by Fieroseverywhere: What kind of MGP you getting with that?

Don't know yet as the swap is still in progress, but based on the ratios of the 6 speed, the engine should be somewhere just above idle at 70 mph. The ratios are not perfect but the 4.9 should sip gas on the freeway:

Gear ratios:
F40

First:
3.77

Second:
2.04

Third:
1.32

Fourth:
0.95

Fifth:
0.76

Sixth:
0.62

Reverse:
3.54

Final drive
3.55

quote Originally posted by zetabird: im wanting to try this swap to but i want to keep the auto thats alredy in the car i have my resons for wanting to do so is it even an option

yeah, but it isnt advisable, the stock caddy tranny has better gearing for its power band, it has an overdrive gear, AND, it is better built to handle the TQ of the 4.9L v8...a 3 speed is a waist of time with that motor, just my humble opinion. the 4 speed with the higher ratio differential gear is the eldorado touring coupe or biaritz, and the seville touring sedan( 3.33:1 vs. 2.97:1 for the regular coupe and sedan respectively)

use the caddy computer, the delta cams "drop-in" camshaft for the best bang for yoru buck. the drop in cam moves the power band up all the way to 5500 rpm

[This message has been edited by aaronrus (edited 11-17-2007).]