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View Full Version : Have been debating building a 383 LT1, what crank?



Samckitt
12-11-2006, 01:40 PM
For those of you who have built a 383, I am curious what crank you recommend. I am thinking about building a 6" rod 383 from an LT1, so I need a one piece rear seal. Tranny is a T56, just an FYI, not that it makes a difference. Instead of going with LT4 heads, can I make good power from the factory LT1 head with a head job of some sort?

Thanks,

speedster
12-11-2006, 01:46 PM
Eagle makes a cast crank good for up to 450/500hp. Past that they make a 4340 forging. My buddy has a 440hp 383 LT1 with a small shot of nitrous. The rods are 6" Scat 4340's. The heads are LT1 with a simple port and 180cc runners. No problems so far.

Samckitt
12-11-2006, 01:54 PM
I take it he running a cast crank with the 440hp motor.

rocketman
12-11-2006, 03:12 PM
The new Compustar line from Callies is real nice,or the Eagle crank is nice.

speedster
12-12-2006, 08:15 AM
I take it he running a cast crank with the 440hp motor.

Yes.

Lowend
12-13-2006, 12:27 PM
The Scat Series 9000 cranks are pretty damn nice, and yes any 1 piece rear main crank will work.

This will shock a lot of people, but the LT4 intake manifold port is actually a worse design than tha LT1 intake port. As a result I'm not a big fan of the LT4 heads in general. CNC heads ( www.CNCheads.com ) in Flordia has dones some port work for me on LT1 heads that have been absolutely outstanding.

I did a 95 Camaro a few years back. Stock bottom end, CNC ported heads, 218@050 cam with 116LS and short headers, 408RWHP!!

Samckitt
12-13-2006, 02:57 PM
Wow, stock bottom end & 408 rear wheel horses! Cool. What compression ratio? What are the exact specs on the cam & if you don't mind me asking, what did the heads cost you? I may go that route instead of the 383.

Thanks

Lowend
12-13-2006, 06:34 PM
I was pretty suprised at the results
It was a Smogger cam from Crane THIS (http://www.cranecams.com/?show=browseParts&lvl=2&prt=5&Vehicle_Type=Auto&Cylinders=8&Engine_Make=CHEVROLET&Year=1995&Engine_Size=305-350%20C.I.&partNumber=104241&partType=camshaft)one I think
I want to say the heads were ~$2500 including everything.
Compression ratio was stock 95 Camaro, so 10-1??

Samckitt
12-13-2006, 08:17 PM
Interesting. I wonder what the same bottom end & heads would do with 11:1 compression & a comp cams 306 cam, .510"/.540", 112 centerline, 230/244 @.050"

Lowend
12-14-2006, 07:33 AM
I have no doubt that a little more duration @ 050 would buy some more power, but keep in mind, the LT1 is hyd-roller lifters which means that no matter what you do the motor is going to be pretty much done at 6500RPM. The valvetrain is just too heavy and the hyd lifters are already pumping up by 6200RPM.
Keep the Lobe seperation in the 113-116 range to keep the MAP sensor happy

Samckitt
12-14-2006, 08:37 AM
The cam is already in it, but haven't been able to finish everything up to get it running. It may be fun to tune it, but hopefully it can be done. This cam is from Comp Cams & they advertise that it is for the LT1.

rocketman
12-14-2006, 11:01 PM
What cam did you pick,A good tuner will be able to tune it,my 396 had monster S/R on a 110 and when it was on the stock computer tuned it.

Samckitt
12-15-2006, 05:11 AM
Here are the specs of the Comp Cams 306 cam I have in my LT1:
Duration: 230/244
Lift: .510/.540 with 1.5 rockers
Lobe Centerline 112 degrees

Motor has 11:1 compression, port match heads to intake, Comp roller rockers, behive springs......

rocketman
12-15-2006, 07:50 PM
Here are the specs of the Comp Cams 306 cam I have in my LT1:
Duration: 230/244
Lift: .510/.540 with 1.5 rockers
Lobe Centerline 112 degrees

Motor has 11:1 compression, port match heads to intake, Comp roller rockers, behive springs......

That's a very common set-up will be easy to tune

Samckitt
12-15-2006, 08:17 PM
Cool, I'm glad to hear that. Do you know anyone that does tuning around Indianapolis, IN Northside?

Thanks

WS6
12-15-2006, 08:25 PM
Speed Inc can do LT motors and they are south of Chicago I believe. Not sure how close that is to you though. I just know it's closer than I am. The CC306 works well in the LT1. I personally prefer a better torque band than that cam delivers, but I am not really interested in drag racing. That cam works better at the drags than any cam I would have chosen.

SStrokerAce
12-19-2006, 11:47 AM
The CC306 (230/244) is a old design for the LT1 and doesn't work the best. You can get a lot better TQ curve by going to a different cam. As far as a 383 goes there aren't really any good shelf cams for them for a LT1.

Bret

Samckitt
12-19-2006, 11:54 AM
Why do you say the CC306 doesn't work good in an LT1?

Any recommendations to use instead of it?

Blaster11
12-19-2006, 01:25 PM
Take a look at this.

http://eportworks.com/index.htm

SStrokerAce
12-20-2006, 10:37 AM
Yeah good suggestion on Lloyd. I'm a little bias because I do his valvetrains and cams.

Bret