4.9 Caddy motor vs 3800 supercharged (Page 1/5)
va441975 MAR 30, 06:03 PM
Which motor makes more horsepower. From what I’ve read the 4.9 is 200 H is that right? It doesn’t sound right so wanted to confirm how much horsepower the 4.9 caddy motor produces. Looking at eventually doing a motor swap and right now the 4.9 and 3800 supercharged is what I’m looking at.

Thank you
Spadesluck MAR 30, 07:59 PM
The 4.9 stock has 200hp and 275 ft/lbs of torque.

The 3800SC (Series II L67) has 240hp and 280 ft/lbs of torque.

The 3800SC is going to be easier to do mods if that interests you at all. The potential output for this motor is very high. There are a lot of swap threads about both these motors. I would suggest searching and reading to figure out what it is you like best.

[This message has been edited by Spadesluck (edited 03-30-2019).]

va441975 MAR 30, 08:41 PM
Thank you for the info! I will do some research on here.

Thank you!
fieroguru MAR 30, 09:31 PM
The 4.9 is a cheap, lightweight, high torque V8 that is a lot of fun to drive, quite fuel efficient with the matching 4 speed auto, and almost always sounds good. It is not a high hp engine and those who have tried to make it into one, haven't been impressed with the results (head flow is the primary issue, followed closely by the intake, eventually the loose cylinder sleeves that are only held in place by the head bolt clamp pressure will limit reliability as hp increases).

The 3800SC is easily the most common swap. Over the years it has had the most vendor support for mounts, harness, performance upgrades, etc. It is a very versatile engine that can be built to 400+ hp and in stock form is very fuel efficient. The biggest two drawbacks are weight and and exhaust note.

I recommend you find people local with both swaps and see if you can get a ride in them and see which one you like better. There is more to enjoying a swapped car than the peak hp numbers.

va441975 MAR 30, 09:54 PM
Thank you for the info! My car has 204,000 miles on the original motor and still runs like a champ but always dreamed of putting a 3800 SC engine in it. I don’t have the capability of doing it but am looking at vendors that could do it eventually.

I appreciate the info!
Blacktree MAR 31, 10:51 AM
The 3800 has much more potential than the 4.9. It also has pretty good aftermarket support. But there is very little aftermarket support for the 4.9 V8, and it doesn't respond very well to performance upgrades. If you just want a cheap easy way to get V8 noises out of your Fiero, you might like the 4.9 V8. But if performance is more your thing, you'll do better with the 3800.
va441975 MAR 31, 11:18 AM
Awesome that was what it was thinking. Thank always wanted a 3800 SC in my Fiero.
olejoedad MAR 31, 11:38 AM
I have a 4.9 Formula and have built/driven several 3800SC.
4.9 power is instantaneous, due to the big torque at low rpm. And it sounds really good.
The 3800SC takes longer to build power, they are fast, but then there is the exhaust sound and the whine of the supercharger.....two noises I personally don't like.
Both are good drivetrain upgrades.
va441975 MAR 31, 12:29 PM
Thank you. What you mean by exhaust sound?
Blacktree MAR 31, 12:55 PM
The 3800 has a pretty bland sounding exhaust note. Some people are OK with it, and some aren't.

Edit to add: You might want to visit YouTube and watch some 3800 Fiero videos to hear it for yourself.

Also note that some of the fastest Fieros (on the Quarter Mile List) are 3800 V6's. The fastest ones have turbos instead of blowers, but the supercharged ones are pretty fast too.

[This message has been edited by Blacktree (edited 03-31-2019).]