Solid Flat Tappet camshaft for 383 SBC

[n2omike]

I'm looking for some opinions on a camshaft choice I'm making for a 383 Small Block Chevy.

The carburetor still needs purchased
has a Victor Jr. intake (could step up to Super Vic)
AFR 210 heads,
1-7/8" Hooker Super Comps, 3" exhaust,
010 block
Callies less expensive line of crank and rods
Pistons are JE with a compression ratio of 10.3. (a bit low)
has Crower lifters with the EDM hole for pressure oiling

It's going into a 1969 Camaro that is to be used as a 'toy'. Power under 3000 rpm isn't really a concern, just maximum reliable power up to around 7000 rpm that won't round the cam lobes off when street driven.

Here's what I've come up with....

Comp Cams Xtreme Energy Solid lobes. These are hyped to have an opening ramp as quick as all but their most aggressive solid racing lobes, but a smoother closing ramp to preserve the valve job and reduce noise. They are also designed for very tight lash settings to further reduce valvetrain shock.

252/260 @ 0.050" with a 106 or 108 lobe seperation. He has 1.6 intake and 1.5 exhaust rockers for 0.578"/0.560" gross lift.

Anyway, here are the lobes...

Intake #6059

290@0.015, 252@0.050", 164@0.200", 0.578" lift with a 1.6 rocker

Exhaust #6061

298@0.015, 260@0.050", 172@0.200", 0.560" lift with a 1.5 rocker

Any comments? Feedback is appreciated!

Thanks!

[Cobra]

What would it take to sell you on a roller cam? If you are not limited, a hydraulic roller would provide you with a superior cam for your application.

[n2omike]

It's not mine. It belongs to a friend who has a baby due any day now, so dropping a grand on a good Roller setup is sort of out of the question. He's pretty much locked in with the solid flat tappet at this point. In the future he may go solid roller.

What sticks out in my mind is the fact that those are some pretty big heads for 383ci, and the compression ratio is a bit on the low side.

I'd like to have the tight lobe seperation and smaller duration to pump up the cylinder pressure... but those good heads probably won't need that much overlap???? I'm sort of leaning towards the 108 LSA right now with those lobes...

Anybody have some good experience, recipies or feedback? (I'm a Ford guy)

p.s. He already has a special grind Crower that specs out at 294/298 (advertised) 264/268 @ 0.050" with a 110 degree lobe seperation and 0.597"/0.570" lift. I thought the duration was a bit high and the lobe seperation was a bit wide for the compression ratio. Comments?

He was also inquiring about the 4,7 firing order swap. I have no experience with that.

Thanks!

Mike

[bigjoe1]

Save your money on the 4 and 7 swap. I do lots of engine builds very much like this. They love the 106 lobe centers.I also find that 1.6 in and 1.5 ex works best. There are some newer profiles that would make more HP, but you are on the right tract. JOE SHERMAN RACING

[n2omike]

Thanks for the feedback, Joe!

I may have to go with the 106 degree lobe seperation, then. Significant improvement over the 108, huh?

Is the Super Victor a good upgrade on this engine? (AFR 210 heads and 1-7/8" headers)

I'll probably have him shop around for an 850 mechanical secondary carb of some sort, unless you have a better idea.

For what it's worth, the car has a 4-speed right now, but he may be converting to an automatic in the future.

Thanks for your input! I feel priviledged to have your ear on this. You da' man!

Mike

[automotive breath]

Mike,
I have plenty of experience with the Isky flat tappet solid lifter cams. For the price compared to a roller set up they are hard to beat and performance is outstanding.

I use three different profiles on 355 SBC engines with 10:1 to 11:1 compression; all are very similar with 106 lobe centers.

Part No. 201547 254/259 @ 0.050” good to 7000 RPM
Part No. 201549 258/263 @ 0.050” good to 7200 RPM
Part No. 201555 263/268 @ 0.050” good to 7600 RPM

Random notes:
Set them up a few degrees advanced to improve low RPM performance.
They work best if you keep the RPM above 5000
They are all tight lash cams; frequent lash settings are not needed, easy on springs
Raising the compression ratio as little as .5 will have a big impact on performance
These cams make good power; we have run 9.50 at 140 with an 11:1 flat top 355 in a 2200 lb Super Gas car
with the AFR 210s and the Isky 201555, Victor Jr. intake, 830 HP, 5500 - 7500 RPM

bigjoe1,
It’s great to have you here; I have always enjoyed your simple straight forward approach.

[bigjoe1]

I ran Isky stuff for years, After I won the Engine Master contest, Scooter from Comp Cams said they would really like me to use their stuff. He introduced me to the head cam designer. and we hit it off right away. When a customer sent me an engine back for a freshenup and all I did was replace the old cam with a new Comp grind,the performance picked up by 50 HP. I was won over. I used those cams you mentioned, they were new back in 1990, and they were real good THEN. On a 550 HP engine, I think you would leave 25 to 40 on the table with that old tech. JOE SHERMAN RACING

[automotive breath]

... I used those cams you mentioned, they were new back in 1990, and they were real good THEN. On a 550 HP engine, I think you would leave 25 to 40 on the table with that old tech. JOE SHERMAN RACING

Thanks Joe, somehow I knew you would provide guidance, exactly what I was hoping for.


Joe, Can you provide a CC part number for a grind similar to Isky 201549?

[Kaotic]

quote
Joe, Can you provide a CC part number for a grind similar to Isky 201549? (or 201547) ?

I know this is an old thread dug up, but also would like to know the answer to above question.

When the budget is not there for a solid roller set-up, some are still searching for a good flat tappet equal to old Isky 201547 or 201549 with todays better grinds, so what is recommended ???

[73c34me]

I ran that same compcam you mentioned in my 383 w/ a victor jr. I loved it, pulled hard to 7000 ish rpm. I have that & matched edm lifters for sale, pm me if you are interested.

[BigBro74]

Isky makes more modern lobes in their magnum XL solids also- check out the 545-A (201546) or 555-A (201556).

[F-BIRD'88]

If the two Isky cams are the right cams for your application they will be very hard to actually beat.

The Comp TL Solid flat tappet oval track-drag series are about similar. EG CS288TLS-6 EG CS280TL-6 (a little smaller)

The isky 201549 is very versitile. If you want more torque down low , advance it. If you want topend rpm, straight up.
And play with the lash a bit. It responds.
It runs and runs and runs. 10.5:1 to 13.5:1 It likes to rev up too. ( good or ported heads, single plane 750+carb

You will have to go to a (good) roller cam to get a real gain over this one in its intended application.
Dyno and track and water tested. My friend created a phone book archive on testing a whole box of camshafts. This cam was champ. It even likes Nitrous.

UD Harold had similar stuff Ultradyne cams. You can get thru Lunati, Bullet or Howards.
The Crane stuff is real good too. You don;t have to reinvent the wheel every week. A great cam design is a great cam design. eg Crane F-256/3634-2S-5 or Crane F-260/3694-2S-6
Compression is your friend (race gas) especially once you get bigger duration than these.

[levisnteeshirt]

put a 304 isky mega cam in a 13-1 383 , guy loves it ,, limited funds so that's what he could get ,,, pulls hard close to 8000 ,, 2nd year on engine in a circle track car , cam shows zero wear , couldn't be more pleased how its doing , 3500.00 engine with a good bit of used parts

[GARY C]

9 years later and he is still getting generic cam recommendations.

Comp has a list of cams for 283 through 400 ci engines.. Pick one.

The Crane fireball worked great in my buddies 327!

[Biteme]

put a 304 isky mega cam in a 13-1 383 , guy loves it ,, limited funds so that's what he could get ,,, pulls hard close to 8000 ,, 2nd year on engine in a circle track car , cam shows zero wear , couldn't be more pleased how its doing , 3500.00 engine with a good bit of used parts

How much valve spring pressure is it running?
Reason I ask is my .570 lift flat tappet cam has done 2 drag seasons and is starting to show wear. 150 seat 370 nose. edm lifters etc.