What do you dislike about your engine Swap? (Page 1/1)
Dennis LaGrua APR 15, 07:22 PM
After doing more than a half a dozen engine swaps I settled on the 3800SC/4T65eHD for my personal Fiero but that was 20 years ago, There are many things to like about this engine in the Fiero but there are a few things that I dislike and I'd like to mention them.
The dipstick is on the front of the engine near the firewall. You've got to stand in the trunk to reach that dipstick, pull it out wipe it, put it back in to get a reading. Then back in again. Its something that I can live with but just a PITA.
Changing the oil filter is not easy, It sits above the right axle and there is not much room to remove it. I have to get it out with a U joint socket bar and an an expandable filter clamp working from below. Then you need to wiggle and lift out the filter an you get a nice supply of oil on the garage floor. You also must use the GM short filter. A full size one won't fit
Putting the filter back you really cant hand tighten it firmly so again you need help from the wrench. Thank god we have the two post Rotary lift.
The exhaust runs with a three inch U pipe into a SpinTech muffler and then goes to the dual trumpets on both sides. We did it this way to save the trunk . There's not much room for a quieter full-size exhaust system there so we live what we have. The thirty-eight hundred engine doesn't have the best exhaust sound but it does provide excellent performance in gas mileage.
The other concern is that my series III engine is 21 years old and while it's low mileage and runs great ,it's a bit dated for today's automotive world
IMO, no swap is perfect so iIll give the 3800SC engine a 9 out of 10.
How do you see your engine swap?

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

olejoedad APR 15, 09:07 PM
I've got a 4.9/4T60E from a 1993 Eldorado Touring Coupe.

Other than an occasional hunting idle on rare occasions, I have no complaints.
CoolBlue87GT APR 15, 09:56 PM
Wow, a difficult question. As your swap, mine has the dipstick is on the front of the engine near the firewall also, it's not to hard to reach. I guess the other thing would be remembering to pull up the the diesel pump ! I put a sticker on the inside fuel door saying "DIESEL ONLY" It's been about 12 years since the swap was created. I wouldn't have changed a thing. I'm glad that the swap works well, while on the road, the engine sound is quieter than a stock engine. Love getting over 57 mpg ! I'm glad that Dave got the cruise control working. I'm still grateful to everyone in the shop that worked on the car.

[This message has been edited by CoolBlue87GT (edited 04-17-2025).]

Larryinkc APR 15, 10:27 PM

quote
Originally posted by Dennis LaGrua:


Changing the oil filter is not easy, It sits above the right axle and there is not much room to remove it. I have to get it out with a U joint socket bar and an an expandable filter clamp working from below. Then you need to wiggle and lift out the filter an you get a nice supply of oil on the garage floor. You also must use the GM short filter. A full size one won't fit


IMO, no swap is perfect so iIll give the 3800SC engine a 9 out of 10.
How do you see your engine swap?





I have had my 3800 Series III SC swap for 11 years, no complaints so far. Lots of fun to drive and sounds great. Mine lost part of the trunk to a Borla crossflow muffler 3" in 2 2 1/2" out into a pair of Rodneys repro MERA tail pipes. I have been told more than once that it sounds like a V8.

Clean oil filter change solution

https://www.fiero.nl/forum/Forum2/HTML/145223.html

[This message has been edited by Larryinkc (edited 04-15-2025).]

fieroguru APR 16, 07:08 AM
LS4/F40/Turbo in mine.

Really happy with it as I have spend years refining it so it has very good drivability, fuel economy, exhaust note, and insane power. The most recent thing I wasn't super happy with was the valve covers and needing to add a catch can, so came up with a solution for both with the same valve cover.
Before:


After:
cam-a-lot APR 16, 08:08 AM
I agree with pretty much all of your points Dennis. It is a great improvement over the 2.8, but heavy and dated by today's standards... With that said, we just wanted to improve the performance from original, NOT try to match the performance of modern cars- that is a losing battle

Kind of like being middle aged, go to the gym to try and lose some weight and improve muscle tone/health. It is to improve on what's there- not to try to match the physique of the 23 year old body builder on the machine beside you. Losing proposition....

LT188GT APR 16, 10:53 AM
My drop in MPG.
Dennis LaGrua APR 16, 11:22 AM
If I may swing the conversation around to what I like about my 3800 swap; it looks nice, provides 29 hwy MPG, is highly reliable, handles decent and is plenty powerful. There is a guy on eBay that races Corvettes with his 3800SC. While the Corvettes edge him out, he's still pretty competitive. Then there is Scott ( Darkhorizon) who ran a 9.87 1/4 mile time at 142 MPH with his modified 3800SC. Yes he did use the juice.
As for the other Fiero I have with the 4.9L V8 swap, that too gets reasonable gas mileage, the engine has a good reliability record, oil filter easy to change, not the best 1/4 mile time but it gives great 0-60 launch that's sufficient for street work. Great hwy mileage. I believe it weighs only 50 lbs more than the 2.8L . Mine has a very LOUD exhaust.
As for the LS3 I do not own one but that engine seems to have it all; lightweight, very powerful, capable of over 500HP, still available, good aftermarket, impressive looking, but heard that the gas mileage is not great.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 04-16-2025).]

Jake_Dragon APR 17, 05:40 PM
SBC mated to a 5 speed.
Archie kit, hands down the water pump is my number one complaint, after that its the starter/remote oil filter.
Frenchrafe APR 24, 11:13 AM
3800 S2 with turbo. Getrag 5-speed.

As said above, the dipstick is a bit of a pain, but not too bad.
I'd say the worst part of my swap is the vibration transmitted to the car (and into the cabin) by the heafty gearbox mounts.
It's a compromise, because I break most rubber gearbox mounts I have ever tried. So the engine is on rubber and the box is on TH400 style poly mounts.
My experiments with banded rubber mounts for the gearbox were not that successfull.

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"Turbo Slug" - '87 Fiero GT. 3800 turbo. - The fastest Fiero in France! @turboslugfiero
https://youtu.be/hUzOAeyWLfM