Dwayne88IROC

I thought it would be fun to pick a cam but there are soooooo many flavors and variables.

I have criteria but all this checking around is making my head pound.

I need beer!!!!!!!

8T8IROC

iTrader: (3)

Speaking with Don today it seems that for my engine project the LT4 Hot Cam and from the close similarity of my motor to Vincent's engine the ZZ-9 both seem like much better choices than the current cam that is in the motor. I would just take your time like Kevin said and investigate a bit, ask other people that are running "close" to the same setup you are thinking of doing and getting their feedback on some ideas. If your project is special enough you can always consider a custom cam, of course that's only going to drive the price even higher

Dwayne88IROC

What do you guys think about these?

Engine list is:
383 w5.7 rods 10.1 to 1 comp.
AFR 195cc street
SuperRam base & top
eventually 1 3/4 headers 1 5/8 for now

Comp cam 08-418-8 dur in276 ex282
w/1.5 rockers lift is in503 ex510

or

Comp cam 08-306-8 dur in284 ex292
w/1.5 rockers lift is in510 ex540(w/1.6 this getting close to max)

or

Crane HR-284-25-12 lG dur in284 ex292
w/1.5 rockers lift is in509 ex528

or

Lingenfelter 74219 dur @.050 in219 ex219
w/ 1.5 lift is in525 ex525 (why his stuff isn't stagered is confusing)

Just a few choices so far.

BGNCHRS

If you have the cam cards (or actual opening and closing degrees) for
each cam I can runs sims for you based on the engine data software I
have at work.

One big key to this is what you are actually looking for. big HP, big
torque, best 1/4 mile time. overall street-ability? first you have to
answer this. then move on to analyzing what cam is best for your
purpose.

You also need to know gear ratio and trans info to get proper operating
range for your setup.

The cam is the LAST thing you pic when building a car. Just because it
works in well in a Chevelle, doesn't mean that it will work in a
Camaro. (weight difference)

If you do have a contact that is running a similar engine combo that
cuts your research incredibly.

I would stay away from Crane. Comp has the best choices. TPIS has the
best that I've seen for TPI street use. Lingy's cams aren't dual
profile because most of his builds have heads that make up for the lower
efficient exhaust sides of most of the shelf manufacturers.

btw.........you need to have all your duration and lift specs at the
same point (usually .050" is the standard to adhere to) as i think on
the comps you list advertised duration which every cam maker has a
different way to get that number.

hope this helps.

Barry F

Dwayne88IROC

A drag racing street car yeah that's what I want. Very streetable with fast 1/4 mile times.

I will be running my stock 3:08's and WC t-5 trans.

I want the RPM range to be 2000 - 5800 (maybe 6000).

What more info do you need other then cam specs for your software program?

10.1 to 1 comp. I will be using 1.6 rocker ratio.

Can you please check what these 3 cams will do?

Comp cam
Model Number 08-304-8
Duration .05"- 210/220
1.5:1 Lift - .500/.510
1.6:1 Lift - .533/.544
Lobe sep - 112deg

Accel/Lingenfelter Cams
Model Number 74219 recomended for 383w/SuperRam
Duration .05"- 219/219
1.5:1 Lift - .525/.525
1.6:1 Lift - .560/.560
Lobe sep - 112deg

GM High-Performance Cams
Model Number 24502586 Hot cam
Duration .05"- 218/228
1.5:1 Lift - .492/.492
1.6:1 Lift - .525/.525
Lobe sep - 112deg


Thanks
Dwayne

8T8IROC

iTrader: (3)

You might want to add the Cost of each of those bad boys, since I thought you were trying to build your "new" motor on a budget. That way people can give you a more of best bang for the buck recommendation on the Cams you've choosen. Just my $0.02.

Kevin91Z

iTrader: (1)

If those are your three choices I'd pick the LT4 HOT cam. Cheapest price and most duration. Dont forget to check the price using our discount at Valencia Chevy.

Dwayne88IROC

So far the LT1 is winning in the desktop dyno checks.

A good flat tq from 2-4k.

I didn't have this on the list but the SLP 51010 had the most horse power.
.05 dur 224/232
1.6:1 rr lift .522/.544
112 deg lod sep

I haven't tried the ZZ9 yet.

BGNCHRS

Dwayne,

The ZZP will not do as well as the LT4 hot cam or the 51010.

I software we use at work is a very advanced design that takes into account for more variables than the DD software can. You can also customize a number of factors.

Next I plug the HP and TQ curve into drag 2000 and base that on the weight and Cd I have for the third gens to get an idea of 1/4 performance with the same motor but with other variables changed, like CR's, flow rates on heads, cam changes, etc.

Barry F

8T8IROC

iTrader: (3)

Wow! :hail: Wish I had all that soffware, not to mention the knowledge you guys have. Please keep posting about the results of the Cams because as things stand I am all set to swap mine out and would like to make sure I will get one that will keep me :rockon: and ing LOL

Dwayne88IROC

So far GM's Hot Cam is the ticket. My engine builder thinks I should go w/more lift to take advantage of the heads. Max .570 lift.

What happens if you raise the lift to .550 w/ the same duration as the hot cam 218/228?

Or maybe the duration of the hot cam on Lingenfelters lift (.560/.560)

Did you plug in the flow numbers of the heads I sent?

I'm still amazed that the ZZ4 did so well.

I'm pulling the motor today after my cub scout troop works on their pine wood derby cars. 15 kids with sand paper all wanting to make tanks. ('')

BretD 88GTA

Dwayne,
I definitely thing the LT4 Hot Cam is the way to go, but the key thing I want to know is have you contacted Steve Spohn about this new motor yet?

You've murdered two torque arms with just your 305, what do you think is gonna happen with a 383, 6000 clutch dump.

85 1C5 IROC

>>I'm pulling the motor today after my cub scout troop works on their pine wood derby cars. 15 kids with sand paper all wanting to make tanks. <<

Dwayne, be thankful they didn't want to make Mustangs....lol

Steve

BGNCHRS

He'll be replacing the scattered T-5 with a T-56 and then the 9-bolt with a 12-bolt because he keeps blowwing the caps off it and gets tired of replacing ring gears

Barry F

Kevin91Z

iTrader: (1)

Actually Dwayne has a 10-bolt 3.08 ratio, but he should get a 9-bolt or a 12-bolt.

BGNCHRS

I thought that MAYBE with it being an 88 IROC it would have a Aussie rear.

Barry F

Kevin91Z

iTrader: (1)

Right, it could, but it was ordered without the G92 options or disc brakes. So the default with a 5-speed is the 10-bolt 3.08 with drum brakes.

Dwayne88IROC

My RPO code for the rear is G80. 3:08's w/al drum.

I do have a "new when I bought the car"(replaced 2 months before I bought it) 9 bolt in the 86.

I think it has the high gears 2.something? Gotta fix that.

I'll have to give that t-5 a kiss when I stall it. Kind of a last kiss good by and good luck little buddy.

No mudpuke pine wood derby cars Scout master orders.

However, I do like to see mudpukes used as demolition derby cars

This new tq arm looks pretty beefy. We'll see

Kevin91Z

iTrader: (1)

G80 is the code for posi-traction. Your code for the 3.08 gears should be GU4.
The crappy ratio in the 9-bolt is 2.77 . You could spend $500 and get a 3-series posi and a set of 3.45 or 3.73 gears for it from Miles, and have a nice almost bulletproof rearend that will last up to 11 second runs. Or keep using the 10-bolt 3.08...

Dwayne88IROC

I have both RPO codes

GU4 3.08 ratio
G80 limited slip


Only $500 for a really good rear end sounds great. But I don't have the $ to do that yet. The 10 bolt will have to suffer for a bit.