How does that 274xe compare to the xs274s? What are the specs for the 274xe? Which cam would be better for a 71 Chevelle, 388ci, 9.5:1C/R, street/strip car with 4.11s out back? What, if any, downs are there from the 2 cams? Thanks

The solid will give you more torque and a higher rev capability. You decide if it's worth the 'hassle'. Oh, and I would always use posi-locks for a solid cam, especially a valve slapper like the Comp line.

I have poly locks on my motor right now, just that they're not locking. I was thinking of buying some 1.6 rollers, but I've had people tell me that it's not worth it and there won't be a differece in performance...but yet, I see people here making rocker ratio changes from 1.5 to 1.6 with increases in et and performance. Anyways, would I benifit from going with 1.6s? Or am I better off staying with the 1.5s I have now and just buy new poly locks? Would anyone happen to know if I would even see a difference by changing to the xe274? Right now, I have a no name brand cam with a .488" lift. I have no idea what the rest of the specs are, but I was told they should be somewhere around the lines of 284 advertised and around 234*@.050 and either a 110 or 112 LSA. TIA graemlins/thumbsup.gif

What heads are you running? Its kinda hard to figure out if the 274XE would be better without knowing your DCR, CR, Static Ration oh by the way Pat Kelly is Da Man for this!

My two cents is that with your 388 you have more motor than my 360 so you may benefit from a smaller cam depending on your heads and how much overlap is bled off. I love my little combo its not much but it seems to work great together. High velocity runners in the head for street small 650 Mechanical secondaries carburetor, remember you can always go more but you maynot make more power. Remember high velocity is what you want!

With those cubes and 4.11 gears I'd run the 284 version.

Do you know what the .050" dur is for the solid? The hyd is 230/236. For a comparable size solid, you'd need about 8º larger, 238/244. This is due to lash.

Originally posted by Pat Kelley:
Do you know what the .050" dur is for the solid? The hyd is 230/236. For a comparable size solid, you'd need about 8º larger, 238/244. This is due to lash. 236/242 - .501/.510 ;)

Originally posted by Spawn22:
What heads are you running? Its kinda hard to figure out if the 274XE would be better without knowing your DCR, CR, Static Ration oh by the way Pat Kelly is Da Man for this!

My two cents is that with your 388 you have more motor than my 360 so you may benefit from a smaller cam depending on your heads and how much overlap is bled off. I love my little combo its not much but it seems to work great together. High velocity runners in the head for street small 650 Mechanical secondaries carburetor, remember you can always go more but you maynot make more power. Remember high velocity is what you want! I got bowtie heads that are ported, 2.02/1.60 I/E vavles, 64cc. I just don't know what CCs they are flowing. As for static C/R, it's 9.5:1, but I have no idea what my dynamic C/R is.

Sounds like you may have a generic copy of the RPM cam in your motor and if you do it is kinda lazy down low b/c it really needs to be installed in an 11 to 1 CR. motor!!

It's something like 300/234/310/244, 112/107, .488"/.510" so imho is a BIGGER cam!!

There is also another cam in this 11 to 1 CR. range that you may have..

292/232/300/234, 108/106, .488"/.488" lift.

This cam would make your motor "talk" to you quite a bit b/c of the 108 LCA thing so does your motor "talk" to you alot at idle??

The other cam should be some smoother at idle due to the 112 LCA...

Hope this helps and I got the cam spec's from my old Wolverine Blue Racer cat with the "Snake" on the front...??

pdq67

Originally posted by pdq67:
Sounds like you may have a generic copy of the RPM cam in your motor and if you do it is kinda lazy down low b/c it really needs to be installed in an 11 to 1 CR. motor!!

It's something like 300/234/310/244, 112/107, .488"/.510" so imho is a BIGGER cam!!

There is also another cam in this 11 to 1 CR. range that you may have..

292/232/300/234, 108/106, .488"/.488" lift.

This cam would make your motor "talk" to you quite a bit b/c of the 108 LCA thing so does your motor "talk" to you alot at idle??

The other cam should be some smoother at idle due to the 112 LCA...

Hope this helps and I got the cam spec's from my old Wolverine Blue Racer cat with the "Snake" on the front...??

pdq67 I have no idea what my LCA is, but I'm assuming my LSA is around 110 or so, but that's just a guess. At idle, she's pretty loud and sounds like I'd have over a .500" lift.