I am thinking about rebuilding the 2.8 litre engine in my 84 Firebird. I know that there was a high output version of this engine made that year. I was wondering what parts I would have to get in order to convert my engine to the high output version, or if it is even possible to do this.

save time and effort.
do the "3.4 swap boogie" (do a search on this forum)
i'm going to.
others on this board have also.

I believe there are simulatiries between the 2.8HO and the FI 2.8's over later years. But i'm not certain on this, you might do good swapping in a 3.4L but, an 84 is acarbed model, and i'm not sure if the intake stuff would work propperly on the 3.4L even if they do, i'd have to say upgrade to the Hi-po intake made my edelbrock (i think) and a 4bbl version also. Wouldn't be a bad idea for you feeding that larger motor, all in all, it'd be a nice swap, and would get u some power back.

Welcome to the board!!! I believe the only difference between an '84 2.8 and the '84 2.8 HO is the heads. The 84 2.8 HO wears the 85-up fuel injection heads, which have larger ports. So you -could- swap on an 85-up 2.8 MPFI (engine code "S")'s heads from a junkyard. And before you put the junkyard heads on, you might want to try your hand at a homemade port job - http://www.sa-motorsports.com/diyguide.shtm

I'm not too sure about the camshaft grind, though. The only data I have on the 2.8 HO is the heads... I'll see if I can find anything tonight.

But carb/distributor/intake/exhaust stayed the same between both 2.8's in '84.

See my old message about 82-84 mods here: https://www.thirdgen.org/techbb2/sho...threadid=61735

And another message here: https://www.thirdgen.org/techbb2/sho...threadid=61147

And check out the "Major tuneup info" message I put up recently. You can use the search button to find it, if it's not on this first page of messages anymore.

whoops dude, forgot that u were new...welcome to the boards
oh, and i'm thinking, the carbed versions of the 2.8L when equipped with the H.O. carb (aftermarket version) gain up to 20Hp with that and a new manifold, if u swap heads, then do the H.O. manifold, and say a larger 4bbl carb, that should be a strong girl....just thinking, but not sure. worth a try, and hell, if u really want to rebuild, change that cam up a bit, get an non-computer controlled carb, run a super lope cam, make it go, bumbity bumbity bump. lol, be nice. and yeh, a port job on the valvues wouldn't be a bad idea either. maybe a three angle.

Let's make it simple.
What's your budget per car?
What's your mechanical ability?
Help us that way.

if your looking to mod your v6 you can get some ideas from my signature below.

I really don't have a set budget for the car, but I'm in college right now. I don't have the money to just get a different engine, that is why I am leaning on rebuilding it, so that I can just put a little bit of money into the project every now and then. I have never rebuilt an engine before. I mainly want to use this project to gain experience. I realize that I will never be able to get a lot of power from a 2.8, but I think that it can do better than what it does.

Thanks for all of the responses that I have recieved so far.

welcome to the board!! in college? not alot of money? i wouldnt even think about rebuilding the engine then.. ur actually goin to be cheaper dropping in a used engine (2.8 or 3.1 or 3.4).. this is on a 84 bird.. hmmm.. that means it has a 2bbl carb.. 100-110hp.. easy

upgrade, heads to the 85-89 2.8.. vaulve job is a must if u remove the heads.. u could attempt that urself, but i wouldnt suggest it, unless u know what ur doing.. heads @ boneyard + vaulve job = $100-250, maybe not that much if u shop around (finding the heads cheap would be the hardest part)..

cam would be my next suggestoin.. crane 2030 is what was used

in the 3.4.. price = $150 range plus installation.. it gives decent power and is alot more aggressive than what u have stock..

edelbrock intake manifold.. the 2bbl manifold should accept the stock carb (i dont know for sure on that, so check first) and have an egr vaulve.. if u dont live in a smog controlled area, the 4bbl manifold and a new carb.. price = $150-200 range, u should be able to install this urself..

3.4 swap (ked85 is the man to talk to about this).. juat a price comparasion.. look around, u should be able to find a used l36 (93-95 v6 f-body) ohv 3.4.. ive seen than as low as $500 and up to $1000.. + about $200-300 in gaskets, fluids and misc parts.. this would the most highly suggested thing to do.. live w/ the slow car now and save for the swap..

those are a little pricy, but if u want more power, thats what i would suggest.. smaller things, exhaust, ignition.. stuff that would transfer to another 60* v6 (2.8 - 3.1 - 3.4) if u ever swapped one later..

85f-bird - yes the intake from a carbed 2.8 will fit a 3.4.. ive seen a 3.4 w/ both the stock intake and edelborck 2bbl..

mike (loomdog)

You're in school, you really should be studying to make more money so you don't have to do this (scrap to get by).
Sell both, buy a good running car, make payments.
Being real.
I have to find a cheap drive train fo my S-10 Blazer.
I got the time & I'm the labor, just need more tools.
I got tranny (actually, two) I'm rebuilding into one great one.
Now, I need the motor.
I may end up getting a high milage 3.4 for cheap.
Why?
For $200-500, I get the job done. All my Blazer stuff is rebuilt (carb, distb) .
You DON'T need an Edelbrock intake. The factory unit is quite good.
All the factory stuff is good. When it works correct. From one that has the same stuff with 211,500 miles on it.
Really sell the stuff and buy one great running car.
So it's boring.
Oh well.
Hopefully, you'll have a very long way to make your life more fun!
PS College Girls are great. I'd rather play with them AGAIN!

Hehe, I'll be the odd-ball here, and say to go for the rebuild! As long as you have a second car, you can take as long as you want on the first one. It'd be a great learning experience, and something to look forward to on the weekends to get away from school. You'd be shocked at the amount of "plans" I drew (and still draw) in the margins of my notebooks!

I have a notebook somewhere with a whole interior drawing of my car, as seen from the driver's seat- it looks awesome. Took me a whole class! Good thing I already knew the class (Pascal data structures)!

1985-1988 Fieros have the 2.8 HO engine.

About the comment on selling the car... I really don't want to sell it because of sentimental reasons. It was my first car, and it was sort of a gift from my dad. I have an 85 Firebird that I use as my daily driver, it is in really good shape and runs perfectly fine. (I hope that I didn't just jinx myself.) I just wanted work on the 84 as a hobby.

Really seriously.
Go get a V-8 & swap it in. Make your effort worth itself.
I just saw a BEAUTIFUL 305 4 bbl engine in a 1979 Monte Carlo in a wrecking yard.
I wish I could put that in my S-10 BLazer.
Don't tell me, I have directions right behind me!
And the V-8 swap exhaust manifolds already, too.
Learn by swapping in a 3.4 in the 85!

Dennis6, that's actually a different motor than the '84 HO. 'Fact, in 1985, with the introduction of MPFI, the 1985 2.8 was dubbed a "high output 2.8". That "HO" designation dropped in 1986.

But good point, the Fieros did get the larger throttle body.

hmm I know where ones sitting ripe for the pluking....

After reading through the message boards more, I'm starting to lean on putting in a 3.4. It might take me a little longer to get the money put togeter to get started, but it does look like I could save a little bit of money on the whole project.

the difference between a regular stock engine and a H.O. stock engine is that the high output one has a less restrictive exaust system....the engine itself is all the same

I believe you're talking about some of the V8's; which got a dual-cat y-pipe. I've never heard/seen that regarding the '84 HO 2.8. (Or the '85 HO 2.8, which is exactly the same as the 86-up 2.8.)