94'BLKBRD

iTrader: (76)

Im Planning On Swapping Out My Cam For A Bigger One,i Want It To Be Streetable But To Make Alot Of Power??and What Cams Are You 383 Guys Running And What Kind Of Horsepower Gains Are You Getting?
Specs Of Engine In Sig.

SStrokerAce

iTrader: (2)

with 8.5:1 compression where is the blower?

94'BLKBRD

iTrader: (76)

It's Coming Soon

SStrokerAce

iTrader: (2)

So you need a blower cam then... because with that 8.5:1 anything NA is going to suck to drive and make power.

From what I have seen, there are very few blower cam specs out there for the public to see that are usefull. They are usually way off from what would make the most power throughout the RPM range the motor is used in.

Bret

DeltaT

iTrader: (5)

That cam you have will make a great blower cam. If I changed anything it would probably be to add 1.6 rockers with the right springs. Remember you need good springs for FI because the boost is putting pressure on the intake valve which can take 60 pounds off the spring's effective rating, depending on your boost level.

Jim

SStrokerAce

iTrader: (2)

IMHO the 214/224 114LSA cam is WAY OFF.

94'BLKBRD

iTrader: (76)

Talked To Mechanic Who Built My Engine And It Turns Out That Another Mechanic Gave Me The Wrong Compression! He Gave Me The Compression From A Lt1 396 They Also Built.my Compression Is 10.5:1,my Engine Is Sitting On The Stand In My Garage.

So What Big Streetable Cam Do I Get?? Gm847,le3??

DeltaT

iTrader: (5)

Take the money that you were going to use for the blower and buy a solid roller cam, springs, retainers, pushrods, 1.6 roller rockers and lifters. With the automatic I recommend either the cam I have in my 383, a Comp Cams Xtreme Street Roller, 230/236, net lift .575/.584, 110 or 112LSA, or if you like some more lope, the 236/242, net lift .584/.593, at either 112 or 114.

These are pretty mild cams that give your 383 a ripping powerband with a lot of torque. The small one's advertised duration is only 268/274, and the larger is 274/280, so they will idle well but spin to say 6200 (small one), and 6500.

A valve adjustment every 6-7K miles is recommended. Adjustment takes about 1hr. total.

The 230/236 idles like a hydraulic roller of around 222/228, but has a powerband like a big hydraulic roller of about 238/244.

Buy everything but the pushrods, and get an adjustable length checker one - that will tell you how long a set of pushrods to get. Summit carries like 30 lengths just for SBC (including LT1/4) in increments of like .004", so it's not too much of a hassle to measure, order and wait a couple days for delivery.

There's a little more valvetrain noise but no other downside. The performance gain on those ported heads of yours plus the 383ci and solid roller will be phenomenal. With the larger cam and your 10.5: I'm guessing a solid 500HP at 6200 /510TQ at 5000, and power everywhere.

Jim

My Site: http://home.mindspring.com/~jim_fisk/id1.html

SStrokerAce

iTrader: (2)

Why would you do a solid roller with only high .500's lift? With 2.0" valves in a 383 you just don't have enough curtain area there and the cam he has already and the one you mentioned are just small, and lacking in a lot of areas for strokers.

I don't wanna jump on your case but I'd stick to the blowers and turbos and stop with the cam advice.

94BLKBIRD,

Let's figure out the compression ratio you really have....

Chamber Size, Piston Volume, Deck Height and Head Gasket size are all you need.

Bret

DeltaT

iTrader: (5)

Cuz he's only running ported LT1 heads? Throwing a .680" lift at them won't have much of a payoff.

but I will anyway?

Either of those cams would work great on his A4 383 TA.

Jim

94'BLKBRD

iTrader: (76)

here's some info on the pistons ,i'll try to get the rest of the info from the builder today

SB-Chevy Heavy Duty Inverted Dome Pistons, .030'' Overbore
Piston Dia.: 4.030''
Piston Top: -28cc Dome,

SStrokerAce

iTrader: (2)

Well I guess you don't get all the concepts of camshaft and motor design then.... you need to look into the concepts of curtain area and how that plays into making HP. You don't pick the lift of a motor based on where the head flow numbers peak. lol

For curiosity sake, how many cams did you design and sell last year? I probably have that beat by about 100 or more...

I'm jumping on your case because you are giving the guy info that will seriously make his motor underperform compared to what it could do.

Bret

SStrokerAce

iTrader: (2)

Sounds good.

With those pistons you are more likely to be around the low 9's for compression in a 383 with LT1 heads.

Bret

DeltaT

iTrader: (5)

What are we talking here - 5%, 10%?

I never said my advice was the best in the world, nor did I try to build myself up by cutting someone else down.

I understand now that you are trying to make a sale, which explains a lot, but that doesn't mean everyone's threads should be locked or their opinions ignored (or not stated) once you step into the ring.

BLKBRD - I'm seeing your compression ratio at about 10:1 with those pistons.

Jim

94'BLKBRD

iTrader: (76)

CHAMBER SIZE IS 64cc, DECK IS .005 AND HEAD GASKET IS .039 THICK

SStrokerAce

iTrader: (2)

I could care less if I sell another camshaft....

I had a customer with a 383 TFS heads ported by Lloyd and a hyd roller cam, that was a emissions setup and it was easily 40hp more than if he had the 214/224 114LSA cam that 94BLKBRD has. If the setup wasn't emissions oriented it would be around a 70hp gain. That's a 10% gain right there and a 6% gain with the emissions cam.

That's my point. Don't bring a knife to a gun fight ;-)

Bret

SStrokerAce

iTrader: (2)

8.7:1 is your compression ratio

94'BLKBRD

iTrader: (76)

Should I Take Advantage That My Engine Is On The Stand And Swap Out The Cam For A Bigger One?? Or Just Leave It Alone And Worry About A Supercharger

SStrokerAce

iTrader: (2)

With the numbers I posted above, does it sound like it's worth it?

Bret

T/A KID

iTrader: (12)

Bret I have been reseaching a lot of your threads and numerous others on Blower cams, From what I see a lot of people say run a wide I/E ratio dealing with duration (anywhere from 10,12+ split)
But lately I see a lot of guys going fast with smaller splits like around a 4-6 degree split especially the LS1 guys. Kp on this board (director in the forced induction section runs 9.48's at 144 with a tiny 204/211 01 Zo6 cam with out of the box Dart 225, forged 347 Ls1, 12.5 lbs of boost on his D1SC, with a 3340 race weight, backed with a 3;70 gear ration and a Th400, cuts 1.3 60 times. The car sounds stock besides the blower wine and the bypass valve .
On my 383 I was thinking something with a 6 degree split with as much lift as I can throw at it using the stiffer big block Beehives. I firgure with boost running through the motor these springs would be my best choice.
When it comes to LSA at boost I have heard just about everything some wider than 114 and some narrower.

DO you car to GIVE A LITTLE BIT of FREE INFORMATION!