I have an original drivetrain 1990 firebird formula with the 305 tbi motor and a t5 5 speed transmission (i believe) my donor engine is a zz4 350 out of my 1980 chevy k20 mud truck. the truck currently has a sm465 (4 speed granny gear) manual trans on it. i am trying to find out if i will be able to directly bolt the t5 onto my 350 block to put it in my firebird. any help or links appreciated. Thanks

 

You have a roller motor now if the swap is a 1980 350 then you are going to flat tappet and will need a different flywheel than your factory one. You will need to off a 85 or older 3rd gen. Other than that it will fit.

 

the 350 is complete and running. id have to look at the numbers on the block in the mud truck. the truck is an 80 thats why im saying its an 80. but bellhousing wise it should work? bolt up?

 

I don't think the 5 speed ever came behind a TBI 305, only TPI 305s.

And as midias said, the only concern would be the flywheel, if both engines have a 1 piece rear main seal then it will be a direct swap, if one has a 2 piece rear main seal then you will need a flywheel for the proper crank. (The flywheel bolt pattern was different between the two different styles.

 

They sure did. I've owned several. Matter of fact my 92 started life that way.

 

Interesting, I've only seen them behind TPIs

 

if it truly is a ZZ4 engine (it will have "ZZ4" stamped on the pad by the water pump) then it is a drop in swap: GM even used to sell a 50 state smog legal kit to put them in certain third gens..

 

It was actually the ZZ3 that originally came out as an emission legal engine swap for 82-87 third gens with the L69 or LG4. My car was swapped to a ZZ3 about 12 years ago but all emissions parts were removed since there is no inspections where I live.


http://www.camarotech.com/engine-ZZ3.html

 

I no concerns with emissions or smog laws for this swap. The mud truck is simply rusted beyond repair and I would like to get some more ( a lot more) life out of my 3rd gen. The 350s mods are "minor bolt ons" headers, high rise intake, cam, and 750cfm carb. I just wanna make sure the t5 will bolt up to it before I go rippin and tearin into everything.

Also, the 305 motor mounts should be the same as the 350 correct? Was gonna get energy suspension mounts just to make sure it doesn't go anywhere

 

Motormounts & bellhousing pattern should be the same. Only issue may be with the headers. There's a lot more space in a full sized truck than a 3rd gen.

 

EVERY external detail about the 305 and 350 are ABSOLUTELY IDENTICAL IN EVERY WAY, except for the numbers cast into the block. (which rarely interfere with anything fitting anything) That means, motor mounts, bell housing flange, header location, and EVERY other external detail.

Motor mounts may be different for a Camaro/Firebird from those for a truck; don't know myself. However that has nothing to do with 305/350, only truck/F-body.

You may still have to contend with year model differences, specifically, the 1-pc rear main seal (86 up) vs 2-pc (85-back). I can't recall which version the ZZ3 was. However within either year range, 350 === 305.

If the year range of the engines is different you will need a flywheel. The stock 305 Camaro/Firebird flywheel from the correct year range that covers your motor, will fit your 350. The motor being wrapped currently in an old truck doesn't matter.

The odds of your truck headers fitting in a Camaro/Firebird are exactly zero. Ain't happenin. You'll need the correct exhaust for your chassis.

The odds of a "high rise" intake fitting under a Firebird hood are also pretty much zero. Camaro has a slightly taller hood and the odds would be better. People will tell you that you can use a "drop base" air cleaner to get it to fit; but it doesn't make too much sense to lower the lid of the air cleaner to where it almost touches the top of the carb which is of course what a "drop base" does. Doesn't too much matter how "high rise" the intake is if all the air has to pass through a tiny slit and then immediately make a 90° turn to go downwards. Might want to start researching intakes compatible with your chassis. They're cheeeeeeep so no need to worry about "cost", it'll disappear into the noise level by the time you get the swap complete.

 

I like what I'm reading. All I need to worry about is the flywheel and headers. Hood is raised no worries there. Now for clutch? Order it like it would be for the original 305? Or?

 

every ZZ series crate motor was based on the one piece rear main seal block: think of a ZZ4 as an LT1 rotating assembly in a 4 bolt TBI truck block with Corvette L98 aluminum heads and a custom camshaft.

yes, order all the clutch pieces for the stock 305.

 

Order the clutch to fit the stock 305, but buy an upgraded one. Stock replacement may not hold the torque of the ZZ4, not sure what the clutches are rated for, but i'm sure the ZZ4 has close to double the torque output of the 305

 

Yea i would never order a "stock" clutch. just didnt know the disc diameter and which P plate to get. getting at least "stage 2"

 

Don't do it unless you totally rebuild it for that kind of power. T5's are junk. I like the 5 speeds but GM was smoking pot when they built that hunk of ****. Better off with a 700 with a shift kit