"Cam race"

[Prix]

Ok, I was thinking about cams after I get a chip and top end swap, most likely the 272 cams but I hear 260 cams can be just as good, but which would benefit a 3000lbs 92 2dr Grand Prix with a pushrod to get it down a drag faster?

[TheProfessor]

id say 260 unless you are running a higher compression ratio
like 10:1 or higher

[SappySE107]

Yup, the 272 is pretty aggressive and without high compression, its going to lack dynamic compression and probably hurt the low end quite a bit.

[dbtk2]

I would definately go with the 260. That or the comp 260. A 272 would be too aggressive for what you want, your lowend would die. I like my 260 cam. And just so you know, unless you've done a lot of weight reduction, your car weighs significantly more than 3000lbs.

Shawn

[SappySE107]

Its at least 3200 pounds and probably closer to 3300.

[v6h.o.]

Re: "Cam race"

Ok, I was thinking about cams after I get a chip and top end swap, most likely the 272 cams but I hear 260 cams can be just as good, but which would benefit a 3000lbs 92 2dr Grand Prix with a pushrod to get it down a drag faster?

In a Drag Race situation, Purely Drag the 272 is the cam to get, However with your Grand Prix im assuming its an Auto? If it is stick to the H260 (crane) or the comp 16-233-4 (260/212 degree) camshaft.

With my 5spd i rev my Comp, 260/260 212/212 duration cam all the way up to its limit of 6200 rpm, the 272 would want even more RPM for full potential, the sad part of auto's is its hard to get valve'd/programed to shift at those RPM's. (well for the 3t40 it is, dont know about the 4t60)

the other problem is i'd recommend the smaller 260 series cams as if your GP is still using the GEN2 3.1L MPFI top end, you are not really going to be able to take full benefit of the larger 272's potential with the gen2 intakes restricting the airflow alot at Higher RPM.

the 272 Needs High compression as well. and is not so emissions friendly as well.

[614streets]

02373
135H
270
270
218
218
.460?
.460?
110
.000?
.000?
42328

http://schneidercams.com/cams/34.




Also solid cams..........

[v6h.o.]

http://schneidercams.com/cams/34.

Will, you have an extra "." in there at the end, so the link doesnt work as you have it,

this should work now: http://schneidercams.com/cams/34

[dbtk2]

Re: "Cam race"

the other problem is i'd recommend the smaller 260 series cams as if your GP is still using the GEN2 3.1L MPFI top end, you are not really going to be able to take full benefit of the larger 272's potential with the gen2 intakes restricting the airflow alot at Higher RPM.

He said he's gonna do a topend swap too. But I would still stick with one of the 260 cams.

Shawn

[1QUICKHATCH]

has anyone tryed the 272?

[Cannonball]

I have an old article in Car Craft showing a 15HP gain in an 80s 2.8 V6 with the 272 cam. I agree with the others about the auto trans, if you have the auto then stick with the 260 but if you have the stick go with the 272. It really doesn't need higher compression to work right, as the old article shows and, being a split pattern cam, it really doesn't hurt lowend as much as you might think. You're much better off with a split pattern cam than a single pattern for this reason.
Obviously it will work better with porting but the rpm requirement isn't much higher than the 260 cam. At most, according to the Crane catalog, it's only 500 rpm more than the 260. The rpm range the 272 starts to make power is also higher (2k) so it's obviously best for a stick where as the 260 would be better for an auto.

The article was done on a 2.8 V6 in a Fiero with it's stock MPFI and iron heads btw.

[TheProfessor]

what is a split pattern cam exactly
i have a 272 but the engines not done yet

[RacerX11]

It means the duration on the intake and exhaust lobes are not the same. Single pattern cams use the exact same lobe pattern on both intake and exhaust. The split pattern cams tend to have broader power/torque curves.

Marty

[TheProfessor]

oh ok thats what i thought

[Cannonball]

BTW just to clarify; when I said the 272 cam starts making it's power at a higher rpm and stated 2k, I meant the 272 starts making it's power in the 2k range not that it started 2k higher. The 260 starts at 1500 rpm.