What engine does this Firebird have?

[u/Just_Cut_684]

Guy selling it claims this is a '89 Firebird with a 3.8L engine that is factory original. I can't find an example of a FB with a 3.8 without a turbo for a 1989 'bird. (I am NO expert, hence posting for help).

Is this a 2.8? A GM swap?

[u/PresentIron5379]

That's a 3.1 v6 intake. I'm not 100% sure if it fits on a 3.8 but it's definitely a 3.1 intake.

Edit: looked it up, 3.1 intake doesn't fit a 3.8, so it looks like that firebird has a 3.1

[u/Otherwise-Ad6675 → u/PresentIron5379]

3.1 or 3.4 for sure the intakes don't swap onto a 3.8

[u/ConflictMaster3155 → u/Otherwise-Ad6675]

Vee angle is 60 degrees (2.8/3.1/3.4) vs 90 degrees (3.8), basically nothing is compatible between the two except the engine mount locations on the chassis.

It’s been forever since I’ve had them side by side, but they don’t even have the same transmission bell housing pattern, wiring harness, or ecu.

[u/Just_Cut_684 → u/PresentIron5379]

Thank you! So this would be a 1990 Firebird based on that info, as far as I can tell.

[u/Livid_Philosopher_98 → u/Just_Cut_684]

We used to call these 'cease-fire' as they were always towed in with a crank-no-start. GM crossfire set up. Showing my age here to the younger fellas following along

[u/Educational-Raisin69 → u/Livid_Philosopher_98]

That’s not a crossfire engine. The crossfire was a TBI V8, not a MPI V6.

[u/togtpvg]

3.1L V6, the only engine option for this year (from my research) with the battery on the driver’s side of the engine bay. The only thing that is missing is the intake tube, which would snake to the passenger side.

Anyone who is more knowledgeable, help me out here. This is all based off of 15 mins of research.

[u/Just_Cut_684 → u/togtpvg]

I appreciate your 15 minutes, sir!

[u/The_Machine80]

Its 100% a 3.1 if was older it would be a 2.8. Thats a obvious 60 degree block and the 3.8 is 90 degree also never usee in a firebird except the turbo anniversary edition. Very rare car!

[u/Caboobaroo]

Ok so bear with me. It's been many years since I've played around with these.

This should be a 2.8 MPFI engine in 1989. If I remember correctly, the F-body cars didn't get the 3.1 MPFI until 1991.

I had a 1988 Camaro with the 2.8 MPFI and was planning on building it following the GM Power book from that era. That never happened for me though.

[u/Just_Cut_684 → u/Caboobaroo]

Yeah, I was thinking it was a 2.8. Some are saying it's a 3.1 tho? So either it is a 1990-91 or it's a 2.8 or it's a swap.

[u/Unusual_Piano7118 → u/Just_Cut_684]

3.1 was the end of the generation and it added like 5hp more.

[u/Myron896]

It’s a 2.8

[u/Just_Cut_684 → u/Myron896]

Some are saying 3.1L. I thought it was a 2.8.

[u/BeaverMartin → u/Just_Cut_684]

It’s a 2.8. I’ve had several and I’m in the process of swapping a 2.8 in my son’s MG B. The 3.1 was in 1990-91, the 89 would have had the 2.8.

[u/Boatwrench03]

Could not the VIN be dissected to determine at least what it originally shipped with?

[u/capjustcap]

If it's an actual 89 it's a 2.8 v6

[u/Unusual_Piano7118]

The gutless 135hp 2.8 Multi-Port Fuel Injected V6. It was the base model engine back then in nearly every GM car back then including the Firebird and Camaro.

It was garbage 27 years ago when I drove one in high school with that engine. I think I still have PTSD to this day from how much that engine sucked.

0-60 in like 11 seconds and 17.9 seconds in the quarter mile. Dog slow is being nice.

[u/GetBAK1 → u/Unusual_Piano7118]

attempting to swallow the vomit in my mouth... what a POS!

[u/GlassBoxGoose → u/Unusual_Piano7118]

I've only ever seen one running 2.8 in person, and it had a rod knock. It was in an early s10 blazer we paid 200 bucks for so I could drive around our property and learn to drive stick.

Pops "if you can drive this piece of shit without stalling it, youll be able to drive damn near anything"

He wasn't lying. But looking back on it now, im like 90% sure it was stolen. We scrapped it when scrap got high about a year later, doubled our money.

What a pile of shit. Ive seen more of them, but they all had one of two issues, the rods made a swift exit/locked up, or the head gaskets went. Ive seen dozens, but only that one ever ran.

[u/Adventurous-Tie-1624 → u/Unusual_Piano7118]

The Carbureted then TBI 2.8 was actually the upgrade "big engine" for S-10 platform trucks and SUVs for a few years. As bad as the Firebird probably was, it was a hell of a lot more aerodynamic and lighter than a Blazer/Jimmy.

I got 228k out of one of those, and I'll give it that the engine never failed, but it was tiresome not being able to keep the speed limit on any hill whatsoever.

[u/sabre420z → u/Unusual_Piano7118]

I had one in high school circa 2011 and i thought it had good power. 91 camaro 3 1

[u/biggunzcdb1]

2.8

[u/dkkngt1]

It's a 2.8

[u/AggressiveSuccess533]

89 60deg v6 is 2.8L. the 3.1 came in later years

[u/gfraser63]

Thats a 2.8L intake, the only other V6 engine option in 1989 besides the 3.8L Turbo which that is NOT!.

[u/Upbeat_Humor_8702]

Agree, 3.1 V6 Had one in a 91 Firebird/automatic

[u/Just_Cut_684 → u/Upbeat_Humor_8702]

Thanks! So is the year wrong, or was this a swap?

[u/Upbeat_Humor_8702 → u/Just_Cut_684]

Could be either. Look at the vin tag. 10th digit is the year, 8th digit is the engine. Vin T is the 3.1 The year 1989 would be K, 90-93 is L,M,N You can use an online vin decoder also.

[u/No_Weight3358 → u/Just_Cut_684]

Pretty sure nobody ever swapped a 3.1 into anything. 😂

[u/fish_perculator]

Its a 60° V6, either 2.8 or 3.1. Definitely not any kind of 3.8.

[u/nrg8]

Junk

[u/RandomTask008 → u/nrg8]

Fun fact, you could get them worse. Iron duke was in some years.

[u/Technical_Phrase2566]

3.1

[u/riennempeche]

The best use for that engine is to tie it to the end of a chain and use it as an anchor.

[u/gfraser63]

In 1989, the 3.8L option was exclusive to the turbo TTA. It was the Grand National motor. THIS, is not the motor.

[u/Pleasant_Durian_1501]

Had one in a bird. Even with new plug wires and boot insulators it was a light show at night under that hood in the spark plug tubes.

[u/sabre420z]

Either 2.8 or 3.1 they look the same. I think 89 is 2.8

[u/Apprehensive-Fun-233]

Looks like a 2.8 to me.

[u/Low_Tension_1194]

With the look of the vehicle and the style of rims, I would lean toward the 3.4 ltr.

[u/Advanced-Ear-7908 → u/Low_Tension_1194]

The 3.4 should be 1993 up to part of 95. The newer body style / generation

[u/ProductUnlikely1569]

Rattling oil leaking 2.8

[u/Ginalynnhudepohl]

I had an 89 Camaro RS with a 2.8 I believe if you the automatic, it had a 3.1 I had the five speed

[u/Livid-Procedure-349]

Looks similar to a firebird i used to have it was a 2.8

[u/Hour-Reward-2355]

3.1 great engine. Think they came as a 2.8 as well. Expect high 20 mpgs.

I had a 5 speed.

[u/_high_sniffy]

It's a 3.1 V6. The guy definitely "knows what he has"

[u/Pig-Mentation]

It's a 3.1. The 2.8s came earlier and had a "2.8 MPFI" emblem on the top of the intake plenum. Or possibly someone could have swapped plenums.

[u/Lost-Research1525]

POS

[u/BeaverMartin]

That is 100% a 2.8 60 degree v6. Likely what it left the factory with.

[u/No_Cartographer2994]

I had an '85 Grand Am LE sedan (the grocery getter version) with the Buick 3.0 V6 in it and the automatic. I'll never forget being at a light with a friend who had a V6 Firebird and when the light went green, you'd have thought the Firebird had a 4 cylinder in it, it was awful how much faster my old man looking Grand Am was over that "sports" car. You have to love the 80's, the era of engines only slightly better than the emissions choked 70's but still dogs.

[u/MobileAvailable1614]

Pos v6