Would a Summit-K1106 paired with Vortec heads modified for high lift, produce nearly 400 HP on a 350? I know people recommend the Comp Cams XE268 for this combo, but the summit cam comes with lifters for a better price. This will be on a carb'd engine and thus the reason it was posted here.

Summit cam specs:

Duration @ 50...
Intake 234
Exhaust 234

Lift...
Intake .488
Exhaust .488

Lobe Seperation 114


XE268 cam specs:

Duration @50
Intake 224
Exhaust 230

Lift...
Intake .477
Exhaust .480

Lobe Seperation 110

The only major difference I see is the Lobe Seperation, in all other areas the summit cam looks more aggressive. Will the lobe seperation harm this setup?

Thanks

 

The Summit cam is less aggressive, by a long shot.

If you look at the full curve of valve motion produced by that old profile (incidentally, the same or nearly the same as the Edelbrock RPM cam), it looks like a slowly rising ramp with a kind of sharp pointed peak and then a slowly falling ramp. If you look at the newer cam, it looks more like a square; closer to instantaneoius full opening, and holds the valve at or near peak lift for far more of the cycle, then drops it to its seat more quickly. So you might see numbers something like 234° @ .050" vs 224° @.050"; but if you follow it a little longer, you'll see things like 185° @ .100" vs 190°, then 150° @ .200 vs 165°, and so on. (Not the exact numbers, I made them up to illustrate the point, see the mfrs' spec sheets for the real numbers) The better cam ends up with a good 20% more "area under the curve" than that old lazy thing that was designed when there were no valve srings available except VascoJet which were so stiff your cam wouldn't last even 10,000 miles.

That's not a wise place to cheap out by $50 or whatever. You'll enjoy the other a whole lot more, and probably make it back in gasloline in less than 2 months if you drive it alot.

 

Anxious to hear replys, have all my peices to change top end over except the Vortec heads which are currently being treated to more extensive port work and then flow tested. They were set-up for a .600 roller cam, so they had to machine the heads to accept the smaller valve springs since the cam I have is Lunati Bracket Master II 292/292 .480/.480 hydraulic, but I figured since I was tore down that much I'd swap cams quick to boot. They machined the heads for the different valve springs and also installed 2.02/1.60 valves since they were at it. Just got my Lunati solid cam this afternoon, new specs are adv. duration of 283/288- actual @.050 244/249 and lift comes in at .530/.543. According to DDyno-don't need a lecture about that thing, just fun to plug in specs and see what happens-ended up with 431hp/6000rpm and 430 tq./4500. Hp/tq curves worked out really well for my stall and shift points so we'll see next month if my research paid off with good results or if I just wasted yet another $1500 for nothing but conversation. Hopeing to get down to 12.0-12.3, but time will be the judge of that since tuning will also be an issue. My short block is just a 355 hyperutectic 4 eyebrow piston with current 9:3.1 compression and I also bought the Felpro .015 compressed head gaskets to boost compression a little.

 

Oh well, doesn't hurt to try and be cheap does it?

Thanks

 

lol, yeah, that's what I thought this was gonna be, oh well it'll make a good back up motor for our crew, oh wait, their all running big blocks
Oh well, experience!! yet another cam swap to put under the belt, I hate cars!!

 

If I was going to choose a Summit cam as a alternative
to a Comp XE268-10, Summit# K1106 is not it.
K -1105 would be the closest one.

Its wider lobe separation tends to work better over all on a closed exhaust system. The narrower lobe separation of the Comp Cam
favours a open/tuned exhaust system and *can* make more power and torque. *But* are more sensitive to exhaust back pressure and tuning.

Although Comp's claim to fame with these XE series of cams is a more intense lobe lift curve, (requires a upgraded valvetrain for best results) the old guard, reliable Simmit/ Blue Racer/ generic grind cams are not near as lazy as RB would have you believe.
In the real world, on the street they work real well.

Again, the summit K1106 would not be my choice for your app.
At or near 400Gross BHP is well within reach.
Good head, induction and exhaust flow are key to reaching that performace level, in either case.

Here are some other sources of other simular budget/ generic
performance cams.

www.competitionproducts.com
www.amotion.com

 

don't skimp there... go with the comp XE cams

IHI how far down the bores are your pistons... was the block decked?

If you had standard 64cc heads on the car before... the compression will come up irregardless of the thin gasket..

standard vortecs are appox 63cc to begin with.. and likely by the sound of it the ones you have may have been, or are going to be decked some.

You can afford to bump that compression up a lot.. especially with that long duration cam.

I'm running a bit north of 10.7 in mine... on 93 octane, and have Zero problems with detonation.

 

Ponykiller, I have zero idea how far down the bores the slugs are, it was a rush deal when we threw it together last year so I could stay in the points. I do know the heads I bought then were 64cc and when they installed the 2.02/1.60 in those heads I actually lost 1cc due to them milling it to fit the valves. I never asked if these new heads were milled or not, but hopefully they are as I'm seeking maximum compression possible. I've always wished since I installed this motor I would've went 2 valve relief instead of 4, but what's done is done. I do know once I tear it apart for this swap I will check pistons so I know exactly what I'm dealing with for compression. So you know if these vortecs take different heat ranged plugs like other motors or is plug selection limited for these things, I've asked a couple other places with no luck. I already got the air gap intake, but wonder if I should'nt have gotten an open plenium, too late again, but it outta still run better than my current combo. I can already pull the tires about an inch when all the stars/moons are lined up right, I'm just after some low 1.7's to high 1.68-9 60's, with both tires hangin every pass.

 

Thanks for the info F-Bird. I will keep the Summit in mind then.