SUM-6901 Cam

[Bruceynz]

Hi Guys,

Has anyone used a SUM-6901 cam in a 318? I have a sum-6900 but wonder if I can get away with the slightly bigger sum-6901 cam in my engine, I have posted these specs before but will do it again, XXX302 heads, performer intake, holley 600cfm carb, summit headers, 3.21 rear end, will the sum-6901 work ok with stock converter?

Summit says stock to 2000 stall but that as we know what works for a 318 may not work in a 360 and vs versa summit don't specify what size engine just 318,340 and 360

In a post someone recommended cam that was really good for a 318, better than the summit cams, more in tune with a 318 as they said the summit cam grind is a chev grind but I can't find it

Brand:Summit Racing Manufacturer's Part Number:SUM-6901
Part Type:Camshafts
Product Line:Summit Racing® Camshafts
Summit Racing Part Number:SUM-6901


Cam Style:Hydraulic flat tappet
Basic Operating RPM Range:1,800-5,500
Intake Duration at 050 inch Lift:218
Exhaust Duration at 050 inch Lift:228
Duration at 050 inch Lift:218 int./228 exh.
Advertised Intake Duration:276
Advertised Exhaust Duration:288
Advertised Duration:276 int./288 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.441 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.441 in.
Valve Lift with Factory Rocker Arm Ratio:0.441 int./0.441 exh.
Lobe Separation (degrees):114
Computer-Controlled Compatible:No
Valve Springs Required:Yes
Camshaft Manufacturers Description:Fair-smooth idle, low-midrange power. Works with stock-2,000 stall, 9:1 and higher compression, and gearing.


http://www.summitracing.com/int/parts/sum-6901/overview/

Thanks
Bruce

 

[aspen77rt]

You would probably want more gear. That cam with a manual and 3.21's sure. Not with an auto with stock converter IMO.

 

[Aspen500]

I think what they mean by "Chevy grind" is it's ground on a Chevy core so it has narrower lobes. Mopar uses larger dia lifters and with a wider lobe, can have steeper ramps and faster opening/closing. Most cams have the narrower lobes except Hughes Engines, Mopar Performance (of course) and probably a couple others that have Mopar size lobes. Hard to explain but you get the idea.

The cam you posted is fairly mild and should be decent in a 318. A lot of what a cam is good for also depends on the compression ratio and heads.

What I've found is, the best way to come up with a cam that'll work for what you have, and what you want it to do is to call the manufacturer's tech line (or in this case, Summit) and talk to them directly. Can save a lot of money, time and grief. Don't ask me how I know this, lol.

Actually, I suspect (but don't quote me) the Summit cams are made by Edelbrock. They have the exact same specs as an Edelbrock Performer Plus and Edelbrock Performer RPM.

 

[aspen77rt]

If I was looking for an OTS cam for my car with the requirements you stated I might look at;

Lunati
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,000-5,000
Intake Duration at 050 inch Lift: 208
Exhaust Duration at 050 inch Lift: 213
Duration at 050 inch Lift: 208 int./213 exh.
Advertised Intake Duration: 250
Advertised Exhaust Duration: 256
Advertised Duration: 250 int./256 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.454 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.454 in.
Valve Lift with Factory Rocker Arm Ratio: 0.454 int./0.454 exh.
Lobe Separation (degrees): 112



CCA-20-220-3
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 800-4,800
Intake Duration at 050 inch Lift: 206
Exhaust Duration at 050 inch Lift: 212
Duration at 050 inch Lift: 206 int./212 exh.
Advertised Intake Duration: 250
Advertised Exhaust Duration: 260
Advertised Duration: 250 int./260 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.432 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.444 in.
Valve Lift with Factory Rocker Arm Ratio: 0.432 int./0.444 exh.
Lobe Separation (degrees): 110

Comp Cams CCA-20-208-2
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 800-4,800
Intake Duration at 050 inch Lift: 206
Exhaust Duration at 050 inch Lift: 206
Duration at 050 inch Lift: 206 int./206 exh.
Advertised Intake Duration: 252
Advertised Exhaust Duration: 252
Advertised Duration: 252 int./252 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.425 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.425 in.
Valve Lift with Factory Rocker Arm Ratio: 0.425 int./0.425 exh.
Lobe Separation (degrees): 110

Crane
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,500-4,500
Intake Duration at 050 inch Lift: 204
Exhaust Duration at 050 inch Lift: 216
Duration at 050 inch Lift: 204 int./216 exh.
Advertised Intake Duration: 260
Advertised Exhaust Duration: 272
Advertised Duration: 260 int./272 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.427 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.454 in.
Valve Lift with Factory Rocker Arm Ratio: 0.427 int./0.454 exh.
Lobe Separation (degrees): 112

Howards
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,200-4,600
Intake Duration at 050 inch Lift: 205
Exhaust Duration at 050 inch Lift: 213
Duration at 050 inch Lift: 205 int./213 exh.
Advertised Intake Duration: 259
Advertised Exhaust Duration: 267
Advertised Duration: 259 int./267 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.420 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.430 in.
Valve Lift with Factory Rocker Arm Ratio: 0.420 int./0.430 exh.
Lobe Separation (degrees): 112


Lunati
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,000-4,500
Intake Duration at 050 inch Lift: 210
Exhaust Duration at 050 inch Lift: 210
Duration at 050 inch Lift: 210 int./210 exh.
Advertised Intake Duration: 260
Advertised Exhaust Duration: 260
Advertised Duration: 260 int./260 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.441 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.441 in.
Valve Lift with Factory Rocker Arm Ratio: 0.441 int./0.441 exh.
Lobe Separation (degrees): 110

 

[brotherGood]

IIRC, and don't quote me..but summit cams were made by Crane. I've got the 6900..does just fine with the magnum heads

 

[aspen77rt]

IIRC, and don't quote me..but summit cams were made by Crane. I've got the 6900..does just fine with the magnum heads

Yip, yip.

 

[aspen77rt]

https://www.youtube.com/watch?v=wmWrIXR_5bA

https://www.youtube.com/watch?v=xJMXl09IAEs

https://www.youtube.com/watch?v=SDXQxAJR6d4


same guy
https://www.youtube.com/watch?v=A5SBzALYWJo

https://www.youtube.com/watch?v=wlYUauOOXeU

https://www.youtube.com/watch?v=wlYUauOOXeU

 

[gtsdude]

The summit 6901 is pretty close in spec to the stock 340 cam, should run pretty good in 318.

 

[Bruceynz]

I currently have a sum-6900 and haven't used it yet, I was toying with the idea of getting the 6901 and selling my 6900 but don't want to go to big in cam that I need to change the converter, will a stock convertor work ok with a 6901 cam spec? the 6901 has 114 LSA so should smooth out the TQ curve at the expense of some peaky HP figure, I am no cam expert but the 114 will also assist with idle. Or am I better to stick with my 6900 cam. I guess what I am really asking is there much to gain to change to the 6901 cam.

Sum 6900

Basic Operating RPM Range:1,200-5,000
Intake Duration at 050 inch Lift:204
Exhaust Duration at 050 inch Lift:214
Duration at 050 inch Lift:204 int./214 exh.
Advertised Intake Duration:278
Advertised Exhaust Duration:288
Advertised Duration:278 int./288 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.421 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.444 in.
Valve Lift with Factory Rocker Arm Ratio:0.421 int./0.444 exh
Lobe Separation (degrees):112


Sum 6901

Basic Operating RPM Range:1,800-5,500
Intake Duration at 050 inch Lift:218
Exhaust Duration at 050 inch Lift:228
Duration at 050 inch Lift:218 int./228 exh.
Advertised Intake Duration:276
Advertised Exhaust Duration:288
Advertised Duration:276 int./288 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.441 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.441 in.
Valve Lift with Factory Rocker Arm Ratio:0.441 int./0.441 exh.
Lobe Separation (degrees):114

 

[Bruceynz]

CCA-20-220-3 looks very similar to the Sum-6900

If I was looking for an OTS cam for my car with the requirements you stated I might look at;

Lunati
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,000-5,000
Intake Duration at 050 inch Lift: 208
Exhaust Duration at 050 inch Lift: 213
Duration at 050 inch Lift: 208 int./213 exh.
Advertised Intake Duration: 250
Advertised Exhaust Duration: 256
Advertised Duration: 250 int./256 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.454 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.454 in.
Valve Lift with Factory Rocker Arm Ratio: 0.454 int./0.454 exh.
Lobe Separation (degrees): 112



CCA-20-220-3
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 800-4,800
Intake Duration at 050 inch Lift: 206
Exhaust Duration at 050 inch Lift: 212
Duration at 050 inch Lift: 206 int./212 exh.
Advertised Intake Duration: 250
Advertised Exhaust Duration: 260
Advertised Duration: 250 int./260 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.432 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.444 in.
Valve Lift with Factory Rocker Arm Ratio: 0.432 int./0.444 exh.
Lobe Separation (degrees): 110

Comp Cams CCA-20-208-2
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 800-4,800
Intake Duration at 050 inch Lift: 206
Exhaust Duration at 050 inch Lift: 206
Duration at 050 inch Lift: 206 int./206 exh.
Advertised Intake Duration: 252
Advertised Exhaust Duration: 252
Advertised Duration: 252 int./252 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.425 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.425 in.
Valve Lift with Factory Rocker Arm Ratio: 0.425 int./0.425 exh.
Lobe Separation (degrees): 110

Crane
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,500-4,500
Intake Duration at 050 inch Lift: 204
Exhaust Duration at 050 inch Lift: 216
Duration at 050 inch Lift: 204 int./216 exh.
Advertised Intake Duration: 260
Advertised Exhaust Duration: 272
Advertised Duration: 260 int./272 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.427 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.454 in.
Valve Lift with Factory Rocker Arm Ratio: 0.427 int./0.454 exh.
Lobe Separation (degrees): 112

Howards
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,200-4,600
Intake Duration at 050 inch Lift: 205
Exhaust Duration at 050 inch Lift: 213
Duration at 050 inch Lift: 205 int./213 exh.
Advertised Intake Duration: 259
Advertised Exhaust Duration: 267
Advertised Duration: 259 int./267 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.420 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.430 in.
Valve Lift with Factory Rocker Arm Ratio: 0.420 int./0.430 exh.
Lobe Separation (degrees): 112


Lunati
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,000-4,500
Intake Duration at 050 inch Lift: 210
Exhaust Duration at 050 inch Lift: 210
Duration at 050 inch Lift: 210 int./210 exh.
Advertised Intake Duration: 260
Advertised Exhaust Duration: 260
Advertised Duration: 260 int./260 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.441 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.441 in.
Valve Lift with Factory Rocker Arm Ratio: 0.441 int./0.441 exh.
Lobe Separation (degrees): 110

 

[Aspen500]

IIRC, and don't quote me..but summit cams were made by Crane. I've got the 6900..does just fine with the magnum heads

I stand corrected! Thank you.

 

[aspen77rt]

CCA-20-220-3 looks very similar to the Sum-6900

No sir, very different.

 

[Steve2961]

Most of the cam characteristics are given based on an engine of around 350 ci. so in a 318, you can expect the cam to act like a slightly bigger cam (sorry, I dont' know how much bigger). Because of the 318's relatively small displacement, I'd stick with the 6900. Especially with the stock converter and a 3.21 gear. If the car's mostly street driven, I think you'll be happier with the low and mid range grunt of the 6900 compared to teh 6901. Besides, you already have the 6900 and New Zealand's a long way to ship a cam.

 

[Bruceynz]

Hi Aspen77rt,

Are you able to let me know how it would perform different, I see the LSA is 110 so HP would be more peaky, other than that how would it perform compared to a summit cam?

Thanks
Bruce

No sir, very different.

 

[aspen77rt]

Hi Aspen77rt,

Are you able to let me know how it would perform different, I see the LSA is 110 so HP would be more peaky, other than that how would it perform compared to a summit cam?

Thanks
Bruce

The Comp Cams XE and Lunati Voodoo cams have far more aggressive ramp rates than both the summit cams. Aggressive ramps allow the valve to reach maximum velocity sooner, allowing more area for a given duration. Increased throttle response, increased cylinder pressure, torque, etc. The Comp XE and Lunati Voodoo look like tamer(smaller) cams on paper when compared to the #6901, but they are not. Don't over cam a street driven car, you will regret it. I will always choose to "under cam" a street driven car slightly, rather than over cam for the combo and usage.

IMO for a street driven car, forget peak horsepower, average horsepower is what you need to focus on IMO, with a nice torque curve. Realistically, how often do you think your going to be hitting 5,000-5,500 rpm in your Doba?


Your engine combo is essentially a stock set-up. Unless those #302 heads intake ports are opened up and bigger valves installed they are nothing more than stock heads. Of course that would cause a mismatch with the smaller intake ports perfomer intake, so the intake ports would have to be opened up. The #302's in stock form don't flow all that great. That being said, your entire top end Carb, intake, heads, are rather restrictive. Not to mention the stock slugs in the bores. You will be lucky to hit 9.0:1 compression. Those #302 will however bump the comp up compared to the stock open chamber heads on there now. However, what you do have going for you is port velocity. That's where a smaller Voodoo or XE cam, which are more aggressive than the #6900/#6901, is right on target for your combo and usage of the car IMO.

As someone suggested, call Comp Cams or Lunati and have them recommend an OTS XE or Voodoo cam and compare it to the #6900/#6901.

Between the 6900 and 6901, I'd stick with the 6900 since you already have it.

 

[Bruceynz]

Hi Aspen,77rt

Do the specs of a cam not show how it actually works, I mean can you ramp the valve open faster with a mopar specific cam because of the larger lifter diameter, thus making a lesser looking spec mopar specific cam perform better than a higher spec cam with smaller lobes for a smaller lifter diameter, I hope I am making sense I am only home taught in mechanics.

In its basics if 2 cams have the same spec but one is designed for the larger diameter mopar lifter, then the mopar specific one will perform better cause you can ramp the valve open quicker? (but then wouldn't that change the duration, hmmmmm) :eusa_wall:

Thanks
Bruce

 

[aspen77rt]

Check this article out.

http://www.hughesengines.com/TechArticles/1camshaftfrequentlyaskedquestions.php

 

[Aspen500]

Faster opening and closing has no direct effect on duration. Duration is the amount of time the valve is open. If you look at a real Mopar specific cam lobe vs one with a Chevy lobe (both cams being equal lift/dur) the Mopar lobe looks rounder (if that's the correct word to use) on the top of the lobe, but the ramps will be steeper. The faster you can get it open and closed, the longer you can have the valve be at max lift. It's like turning the volume up and down on a stereo from 0 to 5 to 0 slowly in a given amount of time vs turning it from 0-5-0 quickly but the 0-5-0 time is the same. It'll be louder longer,,,,,,,,,,if that makes any sense??? That's one of the biggest reasons a roller cam will outperform a flat tappet (aside from the friction reduction). The ramps can be really steep and the valve can stay open farther for longer. I'd love to go roller but, well, you know,,,,,,,,,,,,,$$$$$$$$$$$$$$$$.

 

[Bruceynz]

Yup I see it now, the valve can be open to its max quicker thus for the same durantion let more fuel in, I see the advantages of of a larger diameter lifter, so what off the shelf cam would work good in my combo, there is a list to choose from above I am like a :icon_eyes:

 

[Aspen500]

Cam selection is a science that I never mastered! The really best way is to talk to the manufacturer and get their recommendations.
If you stray too far from stock specs, then you also run into geometry problems using stock valvetrain parts. To get a higher lift, the base circle has to be smaller and at the very least you'll need longer pushrods to get proper lifter preload. In other cases you need the longer pushrods and have to go to adjustable rockers (like I did on my stroker 500) but that's also something the manufacturer could tell you. I doubt you'd have a problem though with any of the cams listed.