1983Zsled

Well, It's winter time up in the land of the Canadian's and that means it's time to start screwing around with our cars over the long, cold, depressing months ahead.

Having said that I'm interested in possibly selecting a new camshaft for my combo. I'm currently running a summit k1103 cam, and I have read that this cam is considered a "old School" grind. I was wondering if there is any advantage to going to a Comp cams, or Lunati newer grind that will be better overall. I would be possibly looking at a overall bigger cam as well. I guess "better overall" is a very subjective term.

Current motor, 350, .030 over, stock crank rods, flat top ( 4 valve relief) hyper pistons, .025 in the hole, .015 head gaskets, vortec 906 heads, modified for lift to .530 and mild port work done, 1.52 roller tips, performer intake, ( quadrajet and factory hood clearance) hedders, 3" cat back, and a Performance 700r4 with a 2400 stall, and 3:42 limited slip rear.

summit k1103 specs here; http://www.summitracing.com/parts/sum-k1103

I was looking at a Lunati cam or a Crane that would be similar..... or larger but want to retain some torque in the lower end. I cruise on freeway at 2250 rpm's at 70 mph.

Here is a Lunati cam Part Number: 10120702LK
Previoius Part Number: 60102LK

• Advertised Duration (Int/Exh): 262/268
• Duration @ .050 (Int/Exh): 219/227
• Gross Valve Lift (Int/Exh): .468/.489
• LSA/ICL: 112/108
• Valve Lash (Int/Exh): Hyd/Hyd
• RPM Range: 1400-5800
• Includes: Cam Kit

As I understand it the newer cam grinds like allow a wider powerband. I drive the car 2000 kilometers a summer, with a trip to the track once in a blue moon. I'm fairly happy with the summit k1103 cam I have now. Lots of bottom end, and pulls all the way to 5500 or so. The guy at the motor shop thinks I can get quite a bit more from a bigger cam like the summit k1105.
I have the motor out to detail the engine bay, so now would be the time to upgrade the cam.


So my question is; Has anyone done exactly what I'm suggesting? Going from a k1103 to a bigger and newer cam grind? What was the result ?

Am I better just to stay with what I have?



Any feedback or advice would be appreciated.


Thanks.....

DeltaElite121

These specs would be a nice step given your current restrictions at a current 9.97 compression ratio (I'm assuming you have 64cc chambers?). Looks like it's the same cam with more lift now that I look more at it, heh.




Hydraulic roller, fair idle. Strong power increase in mildly modified engines with excellent throttle response. Will work with stock converter in 383 and up size engines or 2200 RPM stall speed converter in 305-350 cubic inch engines. Likes 3.23-3.73 rear gears. Also the largest cam for inboard/outboard marine applications.
•Advertised Duration (Int/Exh): 270/278
•Duration @ .050 (Int/Exh): 219/227
•Gross Valve Lift (Int/Exh): .515/.530
•LSA/ICL: 112/106
•Valve Lash (Int/Exh): Hyd/Hyd
•RPM Range: 1800-5800
•Includes: Cam Only


Part Number: 20120711
Previoius Part Number: 60111



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Hydraulic roller, lopey idle. Great street machine cam! Likes upgraded intake carburetor and exhaust. Needs 9.5:1 or better compression and 2500 RPM stall speed converter and a 3.42 or better rear gear ratio.
•Advertised Duration (Int/Exh): 282/290
•Duration @ .050 (Int/Exh): 231/239
•Gross Valve Lift (Int/Exh): .535/.550
•LSA/ICL: 110/106
•Valve Lash (Int/Exh): Hyd/Hyd
•RPM Range: 2400-6200
•Includes: Cam Only


Part Number: 20120712
Previoius Part Number: 60112


Something like this ground on a 108 LSA would be an awesome running/sounding cam, but you'de need to get a better set of springs to run it. This is the one I'd pick honestly with a few tweaks to get that explosive midrange in, but that's just me. I think Alex's Parts sells a decent set of springs that will work with the vortec heads if I recall correctly. I can't remember off the top of my head, though.

NVM, I see it. It's carbureted. Must be the turkey because I'm not seeing stuff, heh.

1983Zsled

The motor I have is a hyd flat tappet lifters.... not roller.
I was thinking about the retrofit upgrade but not doing it now.
I have upgraded springs on my heads already....

Thanks.

1986Z28OWNER

iTrader: (1)

I think the exhaust duration is a little high for 355ci, Id like to see something in the 218/224 duration @ 0.050" range, 0.480-0.500" lift range, and a 110 LSA or maybe a bit bigger (112). The summit cam looks alright, combined with a set of 1.6 rockers I think it would work good.

1983Zsled

I like this cam and it seems to fall in line with what you are saying....
Lunati VooDoo

• Advertised Duration (Int/Exh): 268/276
• Duration @ .050 (Int/Exh): 227/233
• Gross Valve Lift (Int/Exh): .489/.504
• LSA/ICL: 110/106
• Valve Lash (Int/Exh): Hyd/Hyd
• RPM Range: 1800-6200
• Includes: Cam Kit

Part Number: 10120703LK
Previoius Part Number: 60103LK


Is anyone using this now, and will this kill my low end torque?
I would be able to use my 1.52 roller tip rockers as well and stay in the range you suggested, 0.480-0.500"

DeltaElite121

You have a 2400 stall converter.. you're not going to lose any lowend. That's Harold's most recent "XE268" design from the Voodoo line. That cam was designed for street motors.

Are you doing all the work yourself? If it were me, I'd be putting a solid flat in regardless of whether this is a street or strip car (and that is what I did). I replaced my XE274 for a solid and I didn't even use the cam after break-in. It's still sitting off to the side. The solid will give you more power, RPM's, and more aggressive ramp rates, but you'll need to check your valve lash every so often. Not really a big deal.

TreeFiddy

I went from the 1103 generic cam to the comp XE262, no other changes. By comparison, far more zing across the whole rev range, particularly down low - was a bit of a dog with the old cam.

I used the 262 because I'm only at about 9:1, and have a stock convertor. You could go higher to the 268 or 274, or Voodoo etc equivalents, as mentioned above.

1983Zsled

That's what I was looking for some real world experience. I really like the Lunati cam that i mentioned earlier Part Number: 10120703LK.

Will the performer 2116 intake and 3" high flow cat choke it out making it a "dog"?

DeltaElite121

You're looking too much into it. You have a 2400 stall converter, and you're asking if you're going to lose low-end torque like it's going to fall flat on it's face and barely go anywhere (and no, that's not going to happen but you ARE shifting the powerband... that's the point of a new camshaft).. I have two friends that have Comp's 268's equivilent (of which Harold designed BEFORE the Lunati VooDoo cams) and it's fine, even on a stock converter. You have a mild build, so if something is "choking" things I seriously doubt you'll notice a difference at your current power levels. Your headers might depending on what they are, but that's about it.

1983Zsled

OK thanks for the advice..... I have comp cams 981-16 springs on my vortecs. Do oyu think I'd need an upgrade with the Lunati 10120703LK cam?

1983Zsled

I have done some research and believe that this will be the best cam for me.
The Lunati Voo Doo 10120702.

Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,400-5,700
Intake Duration at 050 inch Lift: 219
Exhaust Duration at 050 inch Lift: 227
Duration at 050 inch Lift: 219 int./227 exh.
Advertised Intake Duration: 262
Advertised Exhaust Duration: 268
Advertised Duration: 262 int./268 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.468 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.489 in.
Valve Lift with Factory Rocker Arm Ratio: 0.468 int./0.489 exh.
Lobe Separation (degrees): 112

It will work with my comp springs 981-16 and I'm hoping for a nice little upgrade in power.

Thanks to all who answered my questions.