I have a 95 Buick Roadmaster swapped in to my car. To my knowledge, everything is the same as the f-body engines except the accessories and the iroc heads/slightly smaller cam.
I also find it quite amazing how few people know these engines came in anything other than the f/y bodies..although with iron heads. Engine code is 'P' on the vin. You used to be able to pick one up for less than half the price of an alum head engine. Worked for me.

 

They may run quite well but they were de-tuned to make 260 HP. You can take timing out of a F-body and make it run on 87 octane too.

 

Thank you for further proving my point about the missinformation you kids like to spread about anything but the beloved f-body. They were not detuned, they were setup to make a little more torque sooner in the powerband to move the heavier cars with crappy gearing, the "best" gears you could get behind the iron head LT1 was 3.08, a lot got 2.93 and some were saddled with 2.56 in the wagons no less. Try 2.56 in a car with a base curb weight of 4672lbs like the owners manual for my Roady wagon says and see how well the aluminum head version likes that, trust me it wont. The guys I know who have out of ignorance swapped to aluminum head motors thinking it would be an "upgrade" have confirmed the lesser lowend of the aluminum head motor. Tuning is a BIG part of the peak HP difference between these motors but that does not mean the b-body was detuned it was just setup for a different purpose.
I have good info that emmissions in the heavier car was a part of the cam differences too.

 

What does the gear set and the weight of the car have to do with the engine producing 260 HP instead of the 275 HP in the 95 F-Body?

 

What I am saying is that the higher rpm at which the aluminum head motor makes slightly LESS torque is a bad match for a heavy car with numerically low gears.

I have spoken to tuners that say with basic boltons and good tuning both motors make about the same peak numbers leaving me to question if what was really going in was GM taking torque away from the aluminum head motor in order to save you glass axle.

The other thing you need to consider is that since the b/d-bodies are "grandpa" cars they needed to be grandpa quiet and they choked it badly in doing so. Replacing the rectangular baffle after MAF with a piece of 3" pvc is a documented like 9rwhp and that is still with the 450cfm airbox.

You kids believe octane makes power, it does not, even cammed I ran 87 octane in my car up until last spring when I did the AI stuff and upped compression. I swapped back and forth between pcmforless 93 and 87 octane tuning and I could not tell a difference in performance. Next claim will be that octane allows more timing and that is more power which can be right but is not an accurate blanket statement the way most use it.

 

the iron headed lt1 got more trq than the aluminums got to move a heavy *** car .it had a smaller cam for tighter emmisions oh yeah ever see a skinny kid try push a fat chick off him hard as hell heavy cars need more ***** down low not up top how often did ya see gramps launchin the caddy at 3500 rpm.s not often the power comes on sooner not later like in a f body.....i have a transplanted iron headed lt1 in my 93 camaro out of the hole its a animal starts pullin on my friends alu headed lt1 till my cam runs out but that will change soon

 

cool plan i hope it works.

 

Iron heads had nothing to do with torque down low, the torque down low had to do with the cam. and octane effectively makes power in a f-body, dyno a f-body on 87 octane then do a pcm reset and dyno it on 91 or higher octane, youl'l see a power difference. You need to quit defending your precious iron headed stopchild like its a religious jihad, so you got a car that got ****ty gearing and a smaller camshaft. Camming your car isnt neciscarily going to increase octane requirements, a tune or compression bump will however. You should be thankfull your cars all came with vented optis and a better air scavanging system than f-bodies. If you're that hard upfor a car with better gearing, lighter weight and more topend then buy a f-body. If you like your caprice and want more power then build it for more power, whineing and defending your precious b-body isnt going tochange anything. Answer the posters question and let life go on. 50 lbs of weight on the nose of the car is a lot when it comes to a full drag car, people buy everything to lighten the nose of their f-bodies, fiberglasss hoods, tubular k-members. 50 lbs is a lot to those people, and better flowing stock means nothing when it comes to a full out drag car, do LE3 iron heads flow better than LE3 aluminum heads?

 

I am not saying the irons are better just that you kids want to belittle anything that was not f-body.
I wanted to take advantage of the R&D that has been put into the aluminum heads so I bought a set and went wo AI and had them worked and it has worked out quite well for me.

Look at the posts from the guys who actually ended up putting iron head motors in their f-bodies they confirm the lowend, I am not saying everyone should go do that but it does make an effective repair for a damaged motor.

Far as potential there are bolton b-bodies making over 300 to the wheels.

On the detonation prone thing conventional wisdom says aluminum allows one full point more compression yet the difference is only .4 on the stock motors and you claim the 91 is a good thing for the aluminums, applying a little of your "logic" I have to wonder if it is the aluminums that are more detonation prone.

Another reason to go ahead and drop a motor in with iron heads is it leaves the aluminums sitting on a shelf until you can send them out to be reworked with zero downtime, think even thos of you who love to bash anything non-f-body will agree with me on that one.

 

Assuming were all a bunch of kids is always going to help sell your case I guess next your going to tell us that the F-Body isn't a de-tuned Vette.

 

I live in southern Louisiana, During the Katrina aftermath gasoline was scarce so all I had was 87 octane. My f-body was perfectly happy on 87 octane, not audible pinging and it still accelerated like a raped ape if I got into the gas. People are running 12:1 compression with the aluminum heads on pump gas. The aluminum heads are far less detonation prone, its just that they don't take advantage of that very much from the factory stock.