reamo04

do the b-body's come with a different cam than f-bodys?
I just put a LT1 from a caprice into my car, and it feels like it has more low-end

LiENUS

Yep, the cams geared more for lowend torque to move the heavier b-body. It likely also is producing a little less horsepower as well.

reamo04

alright, i was wondering
I had a dif. cam in my fbody motor than stock (not entirely sureon specs of it) and this one just feels like it has a lot more low end

96capricemgr

Have to consider that the b-body had grandpa quiet intake and exhaust as well as 87 octane tuning. People who want to talk up the "less hp" aspect of this seem to forget these details. Both well tuned with comparable boltons make very close to the same power.

I honestly wonder if what really happened was GM limited lowend on the f-body to save the glass axle. The LT1 b-bodies got the 8.5" which is pretty stout.

AdioSS

depending on your source, the B-LT1 cam is more than 10 degrees shorter @.050 than the F-LT1 cam. But it is also much tighter LSA at 111 instead of 116 or so.

LiENUS

The plastic portion of the intake tract does not account for very much horsepower loss, they both share the same intake manifolds and exhaust manifolds. The B-body lt1 makes less horsepower because it has a smaller cam and lower compression. the "87 octane tuning" is on the f-body lt1s as well so thats not a very good excuse to use.

reamo04

will there be a difference in compression since i used my fbody heads? I had the 643 castings on it right now, and it doesnt really feel like it has less top end or anything, feels the same except with more low-end

96capricemgr

I was not refering to the manifolds atall but rather the airbox and noise baffles.

The b-body did get dual cats and mufflers but the pipes are SEVERLY crush bent and the mufflers are 1 3/4" inside.
Bolton b-bodies, done well, can be 300rwhp are you seriously claiming much more for f-bodies? Keep in mind all b-bodies were A4 and all LT1 b-bodies got the 8.5" axle.

Far as the 87 octane tuning best I know the f-bodies got 91 octane recommended. What do I know though I am just capable of research and thought, lost skills these days.

LiENUS

They run just fine on 87 octane, I had to run 87 during the katrina aftermath because it was all there was, and it worked fine. Theres not a huge difference restriction between the b-body and f-body airboxes as far as I've seen. The big differences come in lower compression and a smaller camshaft. Run the same camshaft in a b-body and f-body engine (with their respective stock heads) and you will see similar power peaks, yes without boltons the b-body will be a little more restricted but the difference won't be huge.

Compression should be the same if you're running f-body heads, the change in top-end isn't much but it is there.

speed_demon24

That's because f-bodys also have a low octaing timing table that it goes to when it gets alot of constant knock retard.

LiENUS

Point being, they have an 87 octane tune, and when I was running 87 octane I couldn't tell any performance difference.