Custom Grind or Off the Shelf

[LowDeck451]

General question... If a guy has a street car (3.55 gear, hp exhaust manifolds) that he wants to run at the track pretty often, would the ‘right’ custom ground cam for a less than perfect combo like this be a better choice than an off the shelf grind? In other words, would you have a better chance of getting the ‘right’ off the shelf cam if you had a better combo, let’s say 4.30 gears, light car, high stall, headers etc.? Hope this makes sense! Thanks.

 

[BSB67]

The details of the build, and the goal for the car will influence the answer. But, there is always a better cam. But how do you know it's better? If you call 5 custom cam grinders, give them all your information, three will be close to one another but still a little different, and the other two will be a lot difference. This is a generalization based on my observations, but I bet I'm close.

So, how do you know if a custom cam will be better than an off the shelf cam?

Some people believe that the MP 528 is the best cam, while other would not go so far to say that. Most would agree that it is pretty good for many exhaust manifold applications.

 

[LowDeck451]

Thanks BSB. My thinking is that the cam companies have to make more compromises in their street/strip cams for all the possible combinations of the public, whereas a custom grinder with the specifics of one customer’s car could nail it down better. Also, I think you might have mentioned in another thread that once you get close to the best cam, there’s probably not much of a difference in the top three cams anyway, or something to that effect. I also realize that in a ‘street/strip’ car, a 10 or 15 horsepower difference between cams would probably be lost in the chassis anyway lol. Interesting subject to me though.

 

[BSB67]

Thanks BSB. My thinking is that the cam companies have to make more compromises in their street/strip cams for all the possible combinations of the public, whereas a custom grinder with the specifics of one customer’s car could nail it down better. Also, I think you might have mentioned in another thread that once you get close to the best cam, there’s probably not much of a difference in the top three cams anyway, or something to that effect. I also realize that in a ‘street/strip’ car, a 10 or 15 horsepower difference between cams would probably be lost in the chassis anyway lol. Interesting subject to me though.

That sounds like something I'd say. Not sure many people would agree so you might not want to hang a lantern on it.

 

[Curiousyellow71]

A few things that usually steer us towards a custom cam are when we are pushing the compression on pump gas, trying to run the vacuum brakes, exhaust manifolds builds, stroker cranks, valve clearance issues and trying to get that last 10hp. LOL
It's good to have what you are looking for at least narrowed down before you call and talk to a custom cam company. I always mention Tim Goolsby at Bullet and their mopar only grinds when custom is mentioned. Back when we did a custom grind from comp cams it went ok, but as I've mentioned before it took longer to give them the credit card info then the cam specs....we were pretty much on our own.

 

[LowDeck451]

Are those Bullet lobes fast or max rate? If so, I don’t think I need or want that for the mostly street driving part of street/strip in my case.

 

[Curiousyellow71]

We like the UD profiles, we have had .842 and .904 UD profiles ground also have cams ground off bullets master list and occasionally a lobe gets recommended that is new not on the list.
You do not have to get a cam ground for a .904 lifter you can get a profile for .875 ford or .842gm and have it ground on to a bb mopar. IMHO doing a .842 chevy on a mopar makes very little sense when doing a custom.. Bullet has so many options, I can't really say what's is fast rate or not, There is 3 letters in there cam lobes that designate the cam style. The UDs are pretty quick but great cams. I think a lot of the comp cams have given the "fast rate" term a bad name by dropping the valve like a falling rock, making noise and going bad from quality issues. I have no idea really what your engine is, but if I am headed to a track my plan is not to go slow! You certainly can screw up the cam choice and go slower!

There may be a off the shelf cam that works well. A custom grind will run maybe 50-75 bucks more from bullet vs. a "name brand` shelf cam from summit..

Heard good things about Jones cams as well.

Usually the first street/strip cam compromise is vacuum to run the brakes. 108 lsa cams are not good vacuum builders, also narrow LSA street/strip grinds are not necessarily great for pump gas.

 

[wyrmrider]

Agree with Curious I'd rather have a mild mopar lobe than a radical chevy lobe with the same specs- lot of FUD and BS on this topic
Bullet has slow and fast rate cams do talk with Tim Directly or you have pot luck (true of any grinder) and do not forget Racer Brown and Engle- both have long Mopar
Experience --
Engle has mild, moderate and max strip only lobes

Agree on Comp and fast close being hard on parts
do not go for a max rate for any given duration on the street
CamCraft has some interesting mopar lobes
Howards seem to go for the Max but are fairly modern, later than the UD Harold profiles Howard has the latest UD Harold did AFIK
AFIK Jones has excellent SFT lobes and absolutely the best HR and SR lobes His Motorhome HFT is best in the low compression class better than Howard and Lunati

 

[beanhead]

No reason NOT to go with something custom spec'd anymore, in my opinion, unless you really understand all the things that go with it. Parts durability, manners, efficiency with the compression ratio etc and how the valve events affect everything. I've been told by people much more experienced that the difference between a handful of cams in a range of maybe two-three sizes may not be more than 10 or 15 hp, so unless you're building for a dyno challenge why not get the cam that best fits all the other criteria. It's not like it costs a bunch more dough and then you get a cam that's actually matched up to your combo and intended usage. All it takes is a phone call (or three!)

 

[LowDeck451]

Thanks all you guys, appreciate your experience. That’s what I was thinking, hoping to hear. Not a lot of extra cost for such an important part.

 

[383man]

I run a Dwayne Porter custom grind solid flat tappet cam in my 63 and I love it. Ron

 

[LowDeck451]

Update...
I submitted a spec sheet for a custom cam to Mike Jones and thought some of you might like to see what he recommended. My car is a ‘69 Barracuda...
383 .060
HP exhaust manifolds
Weiand dual plane
Carter 800 AVS
KB flat tops .005 down
516 closed chamber heads 2.08/1.74 pocket ported (he asks for cfm, I guessed 250)
9.7:1 comp. measured w/.040 quench
727 auto and modified 340 converter by a reputable
Super Stock racer. His estimate, 2500 stall.
Car weight w/driver, 3600lbs (my guess, I’m about 250)

Notes..
Car will be mostly street driven, but will be taken to the drag strip often.

Mike Jones recommended...
208/216 @ .050
.299/.305 lobe lift. .448/.457 @1.5
108 LSA
Single bolt cam core
Hyd. FT

(cam and lifters about $360)
He didn’t mention an installed CL
Honestly, not as ‘big’ as I would have guessed but, I don’t have the experience to critique it either. Also not disappointed or anything like that. Myself, I’d rather have a better cam for my combo than a cool cam sound anytime. I did expect a wider LSA with exhaust manifolds (112ish seems to be the trend I see most often?) from what I’ve read over the years. Anyway, I’ll contact a couple others, I’m curious to see what other cam grinders have to say also. Thanks guys.

 

[Officer Higgins]

You have power brakes?

 

[Officer Higgins]

Update...
I submitted a spec sheet for a custom cam to Mike Jones and thought some of you might like to see what he recommended. My car is a ‘69 Barracuda...
383 .060
HP exhaust manifolds
Weiand dual plane
Carter 800 AVS
KB flat tops .005 down
516 closed chamber heads 2.08/1.74 pocket ported (he asks for cfm, I guessed 250)
9.7:1 comp. measured w/.040 quench
727 auto and modified 340 converter by a reputable
Super Stock racer. His estimate, 2500 stall.
Car weight w/driver, 3600lbs (my guess, I’m about 250)

Notes..
Car will be mostly street driven, but will be taken to the drag strip often.

Mike Jones recommended...
208/216 @ .050
.299/.305 lobe lift. .448/.457 @1.5
108 LSA
Single bolt cam core
Hyd. FT

(cam and lifters about $360)
He didn’t mention an installed CL
Honestly, not as ‘big’ as I would have guessed but, I don’t have the experience to critique it either. Also not disappointed or anything like that. Myself, I’d rather have a better cam for my combo than a cool cam sound anytime. I did expect a wider LSA with exhaust manifolds (112ish seems to be the trend I see most often?) from what I’ve read over the years. Anyway, I’ll contact a couple others, I’m curious to see what other cam grinders have to say also. Thanks guys.

http://englecams.com/

 

[wyrmrider]

ask mike about
H440D64307 256° 202° .307″ .461″
for the intake

have this master on the intake and a similar exhaust he recommended for you
stock exhaust manifolds, TQuad, true 9:1 ported 915 heads .030 quench
rv converter

I have not worked out the timing your 264 degrees @108 vs my 256 @112
plot the timing and see how it works out
duration should move the intake close 4 degrees later but lca will move it back
If he thinks you do need that the later intake close or some other reason for the 8 degree more duration I'd suggest SFT with edm lifters
The 256 lobe has more area under the curve, fatter lobe

My cam works great and I think ground by brother rick like 40 years ago when they were in so cal
BTW their dad was the real deal

mine is on 112, heaverier vehicle and I tow

 

[LowDeck451]

You have power brakes?

Oops. No power brakes.

 

[LowDeck451]

ask mike about
H440D64307 256° 202° .307″ .461″
for the intake

have this master on the intake and a similar exhaust he recommended for you
stock exhaust manifolds, TQuad, true 9:1 ported 915 heads .030 quench
rv converter

I have not worked out the timing your 264 degrees @108 vs my 256 @112
plot the timing and see how it works out
duration should move the intake close 4 degrees later but lca will move it back
If he thinks you do need that the later intake close or some other reason for the 8 degree more duration I'd suggest SFT with edm lifters
The 256 lobe has more area under the curve, fatter lobe

My cam works great and I think ground by brother rick like 40 years ago when they were in so cal
BTW their dad was the real deal

mine is on 112, heaverier vehicle and I tow

I guess you know this cam is 264 adv., he didn’t list it..
Cam# D440/1b, H66299-68305-108

At 264 adv. I get an ICA of 60* installed at 108

Your ICA at 256 adv. would be 56* installed at 108
Maybe because of my higher CR, 9.7?

 

[Curiousyellow71]

Some thoughts...


Typically it's a good idea to run a narrow lsa like 108 for a engine with less displacement and a short stroke to gain some bottom end torque it moves your power band lower. A 383 likes a couple degrees narrower lsa then a 440, a 440 likes a couple degrees narrower then 512.
I am not sure how jones rates seat timing maybe wyrmrider knows? If his cam is 264 @ .006 w 108 lsa I think the cam recommended won't like 9.7 it's to small. Even with good quench.

Other question...
You mentioned going to the track? Does that mean you are going to run slicks or trying to peddle it with a street tire?

 

[LowDeck451]

Some thoughts...


Typically it's a good idea to run a narrow lsa like 108 for a engine with less displacement and a short stroke to gain some bottom end torque it moves your power band lower. A 383 likes a couple degrees narrower lsa then a 440, a 440 likes a couple degrees narrower then 512.
I am not sure how jones rates seat timing maybe wyrmrider knows? If his cam is 264 @ .006 w 108 lsa I think the cam recommended won't like 9.7 it's to small. Even with good quench.

Other question...
You mentioned going to the track? Does that mean you are going to run slicks or trying to peddle it with a street tire?

Drag radials 27” or less to help the 3.55.
I’m assuming wyrmrider knows it’s 264? Jones didn’t list that in my rec., also didn’t mention an ICL.
I’ll talk to him.
You mentioned Tim Goolsby at Bullet, I’ll call him also. Thanks.

 

[wyrmrider]

seat timing @.006 like comp, lunati and others
he also does .006 + lash for his solids (not .020) so durations are consistent no matter big lash or tight lash and can be copared with hyd and hyd rollers
ove course SAE .006 at the valve takes rocker ratio into account
In an old post on his chevy powered boat he shows that for the .842 chevy lifter it takes a 1.7 rocker ft cam to equal the VALVE motion of a HR