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Can anyone tell me what motor mounts I would need to drop my 307 olds motor into the 80 firenza ? It currently has the Buick v 6 in it with a turbo 350 trans all stock . Thanks

Don't know if it has been done yet, maybe someone else will chime in.

Pontiac, Buick, Cadillac, Mopar , even a Ford 4 cylinder have been done by others here, but don't remember a Oldsmobile anything.

Doug in P.R.

well ill be dammed!! i guess ill be the first one? i cant imagine an olds motor not going in an oldsmobile

If I was to go to all the effort to put an olds engine in my olds, it seems like a lot of work for not much improvement to go with a 307. The motor makes barely more hp than your 3.8 does now. Any olds Motor, all the way up to a 455 and everything in between will bolt to the same mounts and adaptations you are going to need to make that 307 work. Bigger is better. JMHO
Roy

Yes fastmax I agree but I already have a nice running 307 olds I’m taking out of my 80 cutlass (built 455 is going in it)and I had no luck selling the 307 . The v6 is a lazy 110 hp at best so the 307 with about 170hp as it sits should be a noticeable improvement .my goal here is to spend very little to make a fun car .

Just put the 455 straight into the firenza, then you only have to pull off one swap! LOL
Roy

350 Diesel block punched out and strokedwith aluminum heads and intake would be nice.

Doug in P.R.

Large hammer, sawzall and a welder.
length is the main problem with the Olds V8 it’s 1.75” longer than a SBC with a short water pump.
you may have to move the radiator forward into the core support, fab the motor mounts, offset the motor to clear the steering shaft, notch the oil pan and clearance the firewall.
The air cleaner may not clear the stock hood.
fab your own exhaust

Smiley wrote:Large hammer, sawzall and a welder.
length is the main problem with the Olds V8 it’s 1.75” longer than a SBC with a short water pump.
you may have to move the radiator forward into the core support, fab the motor mounts, offset the motor to clear the steering shaft, notch the oil pan and clearance the firewall.
The air cleaner may not clear the stock hood.
fab your own exhaust

is that all? anybody want to buy a firenza i guess just take it one step at a time .Roy you got me thinking lol

After getting to know these h bodies a little I’m going to leave things alone for now there is simply too many mods I want to deal with. It’s clear now why people don’t drop olds v8s in these things , for me it’s all or nothing and don’t have the time for all right now . Thanks for the input

Giving up that easy? When I did my Cadillac swap, there was only 2 attempted, #1 was a Vega with 500 that was done as drag car and was abandoned do to being too squirrely, #2 Todd ( 454Spyder) on here tried it on a Monza and gave up , and I tried it and completed it and had a successful run with it for many years till I sold it to move down here.

Anything can be done if you have determination!

Doug in P.R.

my hat goes of to you doug for a job well done i dont give up easy but im working on 3 other things now maybe ill revisit this down the road

The longer length of the Olds Small Block probably explains why Olds never installed the 260 V8 in Starfire's. I always thought it would have been a natural fit, and keep the brand loyalty going. Pontiac was never really interested in selling V8 Sunbirds, that is why they never considered the 301 V8 for them. I think each division having there own V8 in there version of the H-body would have helped.

you could freshen up the V6. valve job, rings,slightly bigger cam, headers and maybe a new carb and intake.

Smiley wrote:you could freshen up the V6. valve job, rings,slightly bigger cam, headers and maybe a new carb and intake.

ive been doing alot of research on this and could definitely get alot more out of the v6.