[68SSlemans]

Hello my friend has a nicely rebuilt 350 with about 8000 miles on er. It needs a little more umph, if you know what i mean. I think the cam is an edelbrock performer, not the performer RPM. He also want a little bigger duration for that beautiful sound we have all come to love. We are thinking on the Comp Cams XE 274H, or maybe the lunati voodoo with .504 lift and 276 degrees duration. The pistons are slightly dished with about 8.5:1-9.0:1 compression. Do you think any of these cams is a good selection.
Thanks,
Chas

 

[eville]

The voodoo 60104 (276) is really going to want 10:1. You may prefer the 60103 (268) at 9:1.

 

[wiskeesour]

I love my CC274H. You will too. With that CR, you want to stay under 230 Dur and 470 or so lift. Bigger is not always better.
Timing and tuning Ive learned can get you a great sound.

 

[68SSlemans]

I believe at the @ .5" the intake duration is 230 on the 274 right? But maybe the XE 268 is the right selection for his motor? anyone else have a good selection, thanks so much so far guys!

 

[travis]

What heads, compression, exhaust system, intake system, tranny/torque convertor, and rear gears? Is he just looking for sound, or more power at any particular rpm band? What kind of vehicle?

The more info, the better. Its kinda hard to make any sort of recommendation without the above info, other than the cams that you selected are a bit big for a 8.5 to 9.0 compression engine.

 

[HarleyD67]

I used to run the XE274 on a mild 350 and it was a blast. At the time I was running stock 65cc heads with 2.02"and1.6" valve with some pocket porting, and a Weiand Stealth intake and headers. But to say for sure I would want to know what your planning for intake and carb. Also rear gears and stall if auto.

 

[68SSlemans]

The car has early model heads, single hump but they are ported to 2.02 and 1.6. The car is an M-21 with 4.11s. IT's got a Edelbrock Performer RPM and an Edelbrock 650cfm. Exhaust is Hooker Super Comp headers with 2.5 inch flowmasters.
Thanx

 

[HarleyD67]

Then go with the XE274 you'll be very happy you did.:thumbsup:
And with the right tuning you can get a great sound as well.

 

[68SSlemans]

I don't know might go with the 268 just to play it safe. Harley thanks for all the imput sir!

 

[travis]

Does the engine have dished pistons? Even with a factory smogger type dished piston you will be right around 9.0-1, maybe a touch higher.
If the heads don't have screw in studs, you might want to look at the crane 282H06, aka the 282 energizer. Cam and lifters for about $120 from summit, works good with a fairly mild valvespring like the Z-28 springs, and the 106 lsa will make it sound tough (considerably lumpier than a XE268) and pull hard in the midrange.

 

[wiskeesour]

I don't know might go with the 268 just to play it safe. Harley thanks for all the imput sir!

LOL Which Harley?....

You would be ok with the setup you have and the 274....gears are pretty steep, and the dual plane I imagine it would work quite well and still get a respectable sound.

 

[pdq67]

Travis,

You mean the old Crane 274H06?? The 282H06 sounds awefully big here is all..

I think Isky's 264 Mega hy-cam will be just about right for him!! And it should "cackle" fine, imho....

pdq67

 

[68SSlemans]

Does the engine have dished pistons? Even with a factory smogger type dished piston you will be right around 9.0-1, maybe a touch higher.
If the heads don't have screw in studs, you might want to look at the crane 282H06, aka the 282 energizer. Cam and lifters for about $120 from summit, works good with a fairly mild valvespring like the Z-28 springs, and the 106 lsa will make it sound tough (considerably lumpier than a XE268) and pull hard in the midrange.

And if the heads are not screw in studs which would you recommend.
Thanx

 

[Rocketrod]

I posted a similar question a while back. Bigger is not always better. Here is a link to the threadck out this thread which contains several Desktop Dyno graphs http://www.camaros.net/forums/showthread.php?t=100037

 

[68SSlemans]

Thands everyone im goin for the cc XE274H. I think the 274 duration and .477 lift will be good.:thumbsup:

 

[pdq67]

Please listen to travis here b/c he know's what he's talking about, imho..

And fwiw, a 274 cam need's right at 10 to 10.25 to 1 CR to run it's best!! That's why I questioned him about the 282 cam he mentioned...

I really figure he meant to say 274H06!!!!!

Come on back, Big Guy...

pdq67

 

[wiskeesour]

Thands everyone im goin for the cc XE274H. I think the 274 duration and .477 lift will be good.:thumbsup:

You will like the XE274. I have built SEVERAL 333/350/377 using 76/72cc heads getting from 8.7:1 and 9.8:1 and for streetability xe274 was dead on. We tried several like the 268 and found them better suited for marine use. The 282, 284 and even the 292 made our street motors dogs till around 4K RPM. so those motors saw loose convertors and tons of N02.

IMHO, to get decent numbers down low with the setup you have and use a HYD cam, you will be happy w/ XE274H from Comp.

Travis is pretty smart. He'll have something up his sleeve, I know.

 

[travis]

Taking into consideration the 4.11 gears and 4 speed (the m21 is the wide ratio box, right?), I would not be afraid to use the 282H06 in this application, but I wouldn't want to use anything bigger with 9.0-1 compression. My concern with using pressed in studs with the larger XE cams is their aggressive lobes *might* start pulling pressed in studs out of the heads. Granted, I am using an XE268 with matching springs with a set of vortec heads with press in studs and it has worked great for 7+ years now, but these was brand new heads...not 40 year old castings. The XE268 pulls great to a little under 6K rpms with a performer rpm intake and good exhaust.
Actually, after thinking about it for a while, I would use the comp cams 275 dual energy hydraulic. It is 219/[email protected], .462/.482 lift, on a 110 lsa. The lobes are a bit milder (easier break in and longer valvespring life, plus less stress on the studs), the 10* intake/exhaust difference will provide a wide powerband, and the 275* intake duration will provide a healthy idle and still provide good street manners. This setup shouldn't need more than 89 octane fuel, and should pull hard from 2000-6000 rpms. Plus, you don't have the XE lines noisy valvetrain...thats a big plus to me even though they do work great.

Normally I wouldn't suggest a cam this size for a 9.0-1 engine, but those gears and 4 speed will easily overcome the torque loss on the low end from lack of cylinder pressure. And don't get me wrong...the XE274 will work, but personally I would like to see .5 to 1 more point of compression and screw in studs for a cam that size. Everybody has their own way of doing things though :thumbsup: Just be sure you use matching valve springs with whatever cam you choose.

 

[68SSlemans]

Yea i have never changed valve springs before is it a major pain in the *** and about the dual energy cams lsa, isn't that the same as the xe at 110. I know most manufacturers use 112 LSA. Thanks

 

[travis]

Comp cams mainly uses a 110 lsa for its street cams. Isky likes a 108, Crane generally uses a 112 or 114, as does Crower.

With the right tool, changing valvesprings is a snap. You don't want to use the stock springs with an aggressive camshaft...at the least you'll float the valves. You could break a spring or stack one solid...neither one a very good situation.