Custom Ground Cams

[bszopi]

a lot of production cars are now using a similar method of cam production

This is how the 3100 and 3400 cams are.

[your_I.D.]

Crower cams will do regrinds for $100.00 each. They can dup. the W41 profile no problem. Turn around time is 5-7 days.

[slick94prix]

Crower cams will do regrinds for $100.00 each. They can dup. the W41 profile no problem. Turn around time is 5-7 days.

That's the cheapest I've heard yet.

[sd_iconoclast]

I talked to Schneider cams, also in San Diego. They did not say how much they wanted, but they also said they could do the DOHC cams.

[your_I.D.]

Just a note worthy differance in 96 cams and 95 cams: note timing flats.
96 on left

[series8217]

My 93 cam flats look like the ones on the left..

[SappySE107]

Yeah, thats backwards, 96 cams are on the right with the single wide flat instead of the 2 smaller flats. Would be nice to know the timing difference though.

[your_I.D.]

No one to my knowlege has measured the clearance in the cam carriers yet

Checked clearance on carriers. Its close. We can't add any height directly to lobe. Lift can only be gained by a smaller lobe base.

[your_I.D.]

I was bored and wanted a little more info on lobe shapes, Intake ver exhaust. So with cam carrier off and upside down. One lifter installed. I pulled out dial indicator and degree wheel(made from old CD and printed degree wheel on a cd label.) Set up dial ind. with a small light cone shaped spring pushing lifter against cam and degree wheel on end of cam. Zeroed degree wheel at highest lift found. Zeroed dial ind.at lowest lift found. Here are my results (degrees are at cam rotation of 360* total. Not crank degrees. Lobe centerline is 0* @ max lift.)

EVO: -70* = .000 inches
-60* = .004
-50* = .055
-40* = .148
-30* = .244
-20* = .312
-10* = .357
0* = .372
+10* = .361
+20* = .325
+30* = .253
+40* = .176
+50* = .072
+60* = .010
EVC +70* = .000

IVO: -70* = .000 inches
-60* = .010
-50* = .050
-40* = .133
-30* = .220
-20* = .284
-10* = .340
0* = .365
+10* = .360
+20* = .331
+30* = .278
+40* = .196
+50* = .105
+60* = .019
IVC +70* = .000

One thing I noticed is, the lowest point on cam lobe is not directly opposite lobe's max lift. Theres a .002 drop right before IVO and EVO. If you zero dial ind oppisite lobe's max lift right before IVO or EVO it will drop to -.002 inches. I used the degree reading when dial ind. cam back up to .000 as a referance for valve open. (info above is not an exact measurement but very very close) Someone wanna plot that in to a lobe shape? :P

[your_I.D.]

Yeah, thats backwards, 96 cams are on the right with the single wide flat instead of the 2 smaller flats. Would be nice to know the timing difference though.

I can do that. Just need to pickup some more cd labels for another degree wheel. Slide one of each year cams in cam carrier. Setup second dial indicator. Lock cams down with flats. set degree wheels at zero and zero out dial indicators. Note at what degree IVO or EVO starts and compare degrees.

Edit: that wont work do to lifter bores are not parallel to each other. So one cam at a time. :P

[fieromadman]

Wow this is kinda depressing that this thread hasn't been updated in so long. Theres alot of good information in here. Anyhow, here is a big update for you.

These are the specs for the custom cams that are in two running Fieros and one that is in progress:

SPECS ARE AT .050
Custom:
INTAKE:
Lift: 396
Duration: 220

EXHAUST:
Lift: 411
Duration: 228

Stock:
INTAKE:
Lift: 369
Duration: 205

EXHAUST:
Lift: 373
Duration: 213

These are strictly regrinds. He took away from the base circle. They work in the engine without any other modifications. I tested the clearance between a leaked down lifter and the valve stem with plastigauge to make sure there was good pressure there and there was. Of course I did this with the cam carriers bolted on and the cam on that valve stem was positioned on the lifter at the base circle. When the engine is running there is no unusual lifter tap. These were made for a Fiero application with a manual tranny so they are made to rev. And that they do. Good power all the way to 7200 RPM's but they dont really start to wake up untill 4000. The low end is good enough for a Fiero though, and the powerband works well with gearing.

I bought the cams through Steve Long Racing cams in California. It was a group buy. My friend at the time Dave Gunsul and Steve came up with the specs for the cams. With the group buy I believe they were 100 dollars a cam.

With these additional modifications, one of the engines with these cams installed was dynoed. The modifications are:
The engine is a 95 crate motor with about 14,000 miles on it now. It has all stock internals with custom ground cams (cam specs are secret ), 96-97 intake manifold swap, a northstar throttle body, an underdrive pulley, power steering and A/C delete pullies, 180* t-stat, ngk plugs, poly mounts from WCF, custom exhaust, larger injectors (36#), spec stage 2+ clutch, and a custom street tuned chip on the 94-95 (OBD1.5) by sinister performance.

It put down:





And heres some pictures of the cams and some testing:











-Jeff Depies

[FieroWannaBe]

damn wish i could get my hands on some.

[ez112]

I'm sorry but with all you have done ON a manual I'm not impressed with them numbers.

There's just so many variables on a manual fiero VS. a W-body automatic. Sure the Fiero will be quick, but on an auto what's going to happen?

[fieromadman]

It's not my car for one. And for two, what serious modifications does it have? The intake manifolds might give 5 horsepower, the underdrive is worth about 5, and the powersteering is worth 5. That engine that was dynoed is basically stock with cams and a few little tweeks and tuning. Besides that, his "custom" exhaust is nessicary to get the engine in the car, and its not a well designed exhaust system. So you take 15 horsepower off of the 230 that is dynoed to the wheels and you have about 215 to the wheels for an otherwise stock engine. Generally stock engines dyno at 185 generously at the wheels? Thats 30 horsepower from the cams. If you ask me thats nothing to shake a stick at. Also, if you assume 15% loss at the wheels that engine is putting down about 264 horsepower at the crank. So thats about 49 horsepower over stock with the modifications that are done. Obviously there are MANY more variables to that equation, and alot of what I've said are rough estimates, but seriously!

Now, for an automatic w-body, would I EVER reccomend these cams? Hell no. They dont generate enough low end, at least not timed straight up. This is why we didnt share specs untill now on the cams, because we dont want everyone to think that this is the one and only aftermarket grind that will work. Obviously that is not true. For a manual Fiero application where you dont need as much low end, these are spectacular! The more supporting mods that are done to this engine and the more the cams will perform too. Ported heads, headers, and ported/custom intake manifold later and realisitcally you are going to be sitting pretty damn well.

More than anything I posted that to get peoples brains thinking about doing different grinds so we can do some research and figure out whats best for each application. Now that we have proof that some fairly big regrinds work, and that they are not thousands of dollars, it would be great to try some different specs and see what we come up with. Call Steve Long Racing cams and talk to him about what he can do! Thats what Dave Gunsul did.

[ez112]

Yeah good point. I retract my statement.

I did call Steve long a long time ago. This was back when I didn't have cores. I asked him about adding low end to the cams because it was going go on an automatic. I knew about these regrinds before and heard that these wouldn't work too good on a heavier automatic. He said he COULD do something about it.

Now the part is if he'll still remember me, heh.

I don't like my car right now though, so I don't know if this will ever happen....