power difference between different brand cams

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Orr89rocz
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Re: power difference between different brand cams

Post by Orr89rocz » Thu Jun 29, 2017 9:21 am

bigjoe1 wrote:I gave Chet Herbert a very good Isky cam to copy, and his copy was 20 HP LEES than the real thing from Isky- So much for the exact same thing





JOE SHERMAN RACING
Well obviously the copy didnt turn out a true copy then.


I dont understand a test like this...different brands have their different lobes for different applications. You could take several comp cam lobe families, similar .050/.200 and lift figures to a degree, and test the cams on various icl lsa etc, and find various gains/losses in power.
Does not mean one lobe family was best lobe of all, just means it was best for the particular application!

So many variables a cam lobe is designed for

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Re: power difference between different brand cams

Post by Frankshaft » Thu Jun 29, 2017 10:04 am

We definitely got a conversation going. lol. Anyhow, sorry for the suspense, the 2 cams were nearly identical in power. Same peak tq, at same rpm, there was a slight drop in tq from the Erson cam at 5900, 6000 and 6100, about 6 ft/lbs. I think the difference was oil pressure. On dry sump engines I have done, I have seen 1 lb of oil pressure make 1 hp diff. Like, start pulling it with 95 lbs, and say, that's to much, drop it to 70, and literally it picks up 25 hp. This one was up from 65lbs to 75. It has a new, different oil pump, as lifter shrapnel took out the old pump. Also, the different style lifter could be not bleeding off as much oil pressure. Either way, its up 10 lbs, which, for this deal is actually good. Its just a bracket race deal, and he double enters the thing usually, so, it gets run a lot. After 6100, it is nearly identical. Flip flops 1 or 2.

So, it wasn't to exciting, the Erson cam made for all practical purposes, the same exact power. One other thing, when we dynode it last, we dumped the break in oil, and tried Shafer synthetic 5-50, he swears by the stuff, runs it in everything. It made more power, we didn't do that this time, and it matched peak hp. So, is it possible the Erson cam makes a few more peak hp, I think it does. So, for losing 20-50hp, ahhh, no.

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Re: power difference between different brand cams

Post by Warp Speed » Thu Jun 29, 2017 10:14 am

randy331 wrote:
bigjoe1 wrote:After I won the EM Contest, Comp made me a similar cam to show what I was missing- It made 20 more HP than the Isky I won with. That was when I started using Comp all the time.
Comp probably just narrowed the LSA 1 deg. I've heard that's worth 100 emc points. :lol:

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Re: power difference between different brand cams

Post by Warp Speed » Thu Jun 29, 2017 10:18 am

Frankshaft wrote:We definitely got a conversation going. lol. Anyhow, sorry for the suspense, the 2 cams were nearly identical in power. Same peak tq, at same rpm, there was a slight drop in tq from the Erson cam at 5900, 6000 and 6100, about 6 ft/lbs. I think the difference was oil pressure. On dry sump engines I have done, I have seen 1 lb of oil pressure make 1 hp diff. Like, start pulling it with 95 lbs, and say, that's to much, drop it to 70, and literally it picks up 25 hp. This one was up from 65lbs to 75. It has a new, different oil pump, as lifter shrapnel took out the old pump. Also, the different style lifter could be not bleeding off as much oil pressure. Either way, its up 10 lbs, which, for this deal is actually good. Its just a bracket race deal, and he double enters the thing usually, so, it gets run a lot. After 6100, it is nearly identical. Flip flops 1 or 2.

So, it wasn't to exciting, the Erson cam made for all practical purposes, the same exact power. One other thing, when we dynode it last, we dumped the break in oil, and tried Shafer synthetic 5-50, he swears by the stuff, runs it in everything. It made more power, we didn't do that this time, and it matched peak hp. So, is it possible the Erson cam makes a few more peak hp, I think it does. So, for losing 20-50hp, ahhh, no.
Need to work on that dry sump system! :wink:

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Re: power difference between different brand cams

Post by cstraub » Thu Jun 29, 2017 10:23 am

Frankshaft wrote:To further elaborate about title, what's the thoughts on similar cams from different manufacturers? I just freshened /fixed an engine for a customer that I originally did from scratch. I think I have cycled out the last set of JUNK comp cams lifters from the engines I have built. Never again comp anything for me. Anyhow, obviously the cam was ruined too. This is a good running 406sbc, Dart block, Rhs heads, that I ported, it makes upper 600's for hp, so its no slouch. On most internet dynos, it would make way over 700, lol. Just a strong, basic bracket race deal. Anyhow, new rings, bearings, fresh hone, gaskets, and new Erson/Morrell super duty lifters, and a Erson cam, to replace the comp grind that was in it. Lucky there was minimal or zero damage from the shrapnelled lifter. Nearly identical specs. 1 less at .050 on intake, same ex duration, same lobe Sep, and same lobe lift on both in/ex as old cam, installed at the same intake centerline. I just had as similar of a cam I could, so no potential changes needed to converter, gear etc was needed. Any guesses ? I know I have heard claims from at least one speedtalker who says comp cams make 20-40 more hp than any other cams that are the same size. This Dyno also repeats 1 year, 3 years, 6 years, etc later like dead on, so, its 100% accurate. This spring I have freshened and redynoed 3 engines, that were originally dynode there, and the sheets and graphs would have overlayed each other to the point they were nearly identical.

Thoughts? Guesses?
The Math is the Math. If the cam specs are what the engine needs then there should be no gain. Many over the years have contacted me for a cam change only to get a degreeing instructions or a new lash setting. If the cam they have is only slightly off and I can tweak it with a little labor on the customers part that is all I do. No sense in selling them a camshaft. Bad for the bank account but I sleep at night.

Now if a cam is way off and I can prove it with a lash change so the customer sees it I will do this. Without money changing hands the customer can see first hand the cam in the engine is wrong. You pick up a couple 10ths with a lash change it is an eye opener for them.
Chris Straub
Performance Mfg.
http://www.straubtechnologies.com
www.distributorgears.com

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Re: power difference between different brand cams

Post by Frankshaft » Thu Jun 29, 2017 10:25 am

Any hints? Wrong pump? Again, it was a bracket deal, nothing super scienced out. I was surprised it picked up that much. There is a lot of power hiding in the oil, oil sysyem and windage, that is for sure. I have seen 2 quarts of oil either gain, or lose 20 hp, numerous times on wet sump deals.

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Re: power difference between different brand cams

Post by CGT » Thu Jun 29, 2017 11:00 am

Frankshaft wrote:We definitely got a conversation going. lol. Anyhow, sorry for the suspense, the 2 cams were nearly identical in power. Same peak tq, at same rpm, there was a slight drop in tq from the Erson cam at 5900, 6000 and 6100, about 6 ft/lbs. I think the difference was oil pressure. On dry sump engines I have done, I have seen 1 lb of oil pressure make 1 hp diff. Like, start pulling it with 95 lbs, and say, that's to much, drop it to 70, and literally it picks up 25 hp. This one was up from 65lbs to 75. It has a new, different oil pump, as lifter shrapnel took out the old pump. Also, the different style lifter could be not bleeding off as much oil pressure. Either way, its up 10 lbs, which, for this deal is actually good. Its just a bracket race deal, and he double enters the thing usually, so, it gets run a lot. After 6100, it is nearly identical. Flip flops 1 or 2.

So, it wasn't to exciting, the Erson cam made for all practical purposes, the same exact power. One other thing, when we dynode it last, we dumped the break in oil, and tried Shafer synthetic 5-50, he swears by the stuff, runs it in everything. It made more power, we didn't do that this time, and it matched peak hp. So, is it possible the Erson cam makes a few more peak hp, I think it does. So, for losing 20-50hp, ahhh, no.
Thanks for sharing your results, I appreciate that. Its nice to see some "actual" results devoid of theory, speculation, or marketing intention. How much Peak Torque does the engine make, if you don't mind me asking? Any chance of viewing some dyno sheets? Sounds like a nice bracket piece.

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Re: power difference between different brand cams

Post by CGT » Thu Jun 29, 2017 12:49 pm

bigjoe1 wrote:I gave Chet Herbert a very good Isky cam to copy, and his copy was 20 HP LEES than the real thing from Isky- So much for the exact same thing





JOE SHERMAN RACING
Im guessing it wasn't a good copy. Were either cam doctor'd? Or lift curve checked with a degree wheel? I know some "boutique" grinders copy lobes, and they tend to be off from the cam card.

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Re: power difference between different brand cams

Post by CamKing » Thu Jun 29, 2017 1:50 pm

Orr89rocz wrote:
bigjoe1 wrote:I gave Chet Herbert a very good Isky cam to copy, and his copy was 20 HP LEES than the real thing from Isky- So much for the exact same thing





JOE SHERMAN RACING
Well obviously the copy didnt turn out a true copy then.
Nope.
For example.
Say the Isky Lobe master had .0005" runout, then it was ground on a cam core that was only straightened to within .0005".
Now you copy it on a grinder that adds another .0005" runout, then grind it on a cam that's only straightened to within .0005".
What you end up with, is a POS.
Mike Jones
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jonescams@bellsouth.net
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(704)489-2449

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Re: power difference between different brand cams

Post by CamKing » Thu Jun 29, 2017 1:54 pm

In summery.
You take a run of the mill cam from one company, and a run of the mill cam from another company, with the same specs, and low and behold, they run about the same.
No idea if one floats before the other.
No idea if one will wear-out the valvetrain sooner then the other.
No idea if the specs are correct for the application.


Great test.
Mike Jones
Jones Cam Designs
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jonescams@bellsouth.net
http://www.jonescams.com
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Re: power difference between different brand cams

Post by GARY C » Thu Jun 29, 2017 1:59 pm

CGT wrote:
bigjoe1 wrote:I gave Chet Herbert a very good Isky cam to copy, and his copy was 20 HP LEES than the real thing from Isky- So much for the exact same thing





JOE SHERMAN RACING
Im guessing it wasn't a good copy. Were either cam doctor'd? Or lift curve checked with a degree wheel? I know some "boutique" grinders copy lobes, and they tend to be off from the cam card.
In the early 90's I know of several guys running herbert cams and winning their local classes but the machine shop I deal with said in his dyno testing the herbert cams were usually down on power vs comp and inconsistent lobe to lobe, I don't know if they did their stuff in house, when I dealt with them in early 2000 they had me contact a guy named Don Johanson for custom cams...I don't know if that was good are bad. Their catalog lobes looked lazy...maybe old school?

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Re: power difference between different brand cams

Post by cstraub » Thu Jun 29, 2017 5:31 pm

CamKing wrote:In summery.
You take a run of the mill cam from one company, and a run of the mill cam from another company, with the same specs, and low and behold, they run about the same.
No idea if one floats before the other.
No idea if one will wear-out the valvetrain sooner then the other.
No idea if the specs are correct for the application.


Great test.
And how one cam company ends up with "new Lobe designs" borrowed from another. I've learned more about integrity in this thread than anything.
Chris Straub
Performance Mfg.
http://www.straubtechnologies.com
www.distributorgears.com

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Re: power difference between different brand cams

Post by blwilliams » Thu Jun 29, 2017 5:47 pm

Here is a question I have pondered more than once.
Depending on the cam grinding machine wear and tear, how close is the indexing between cylinders?
We degree the cam off of #1 cyl, how close is that IO EC figure on the other 7 cylinders?
If a machine is worn and unable to duplicate from cyl to cyl or even lobe to lobe, that can't be good.
Even if just the lobe separation varies from cyl to cyl, that is going to not be optimal.
Just wondering.

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Re: power difference between different brand cams

Post by F-BIRD'88 » Thu Jun 29, 2017 6:13 pm

Just to clarify your testing. did you test both the old cam and the new cam in this same new motor? Or did you only now test the New Erson cam and are comparing that test to old previous dyno tests of the old motor with the old (evil) cam?

One is A-B cam testing. 2 cams tested in the same motor.

The other is not A-B cam against cam testing. it is something else.

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Re: power difference between different brand cams

Post by PackardV8 » Thu Jun 29, 2017 6:19 pm

Nope.
For example.
Say the Isky Lobe master had .0005" runout, then it was ground on a cam core that was only straightened to within .0005".
Now you copy it on a grinder that adds another .0005" runout, then grind it on a cam that's only straightened to within .0005".
What you end up with, is a POS.
Surprised Mike didn't mention how copying from the small cam lobe to make a large master magnifies any inaccuracies when transferred then back to the small lobe when grinding a copy. That's why a cam master is many times larger than the lobe.
Jack Vines
Studebaker-Packard V8 Limited
Obsolete Engineering

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