383 Engine Build
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 1,089
Likes: 43
From: Native Californian CALIFORNIA
Army
383 Engine Build
I have a local builder that has suggested these specs for my car based on 3:08 rearend, TH400 tranny and stock converter.
Block - .030 over
Pistons - Speedppro Forged piston L2491F30
Heads - Dart Iron Eagle Heads - 200cc runner 2.02/1.60 valves .550 max lift part # DIE111 9.88:1 SCR
Intake - Edelbrock performer intake
Cam - Comp hydraulic cam # 12-242-2 Duration Intake 224 Exhaust 230 @.5 LS 110 Lift intake .477 Exhaust .48
Carb - stock Qjet
Exhaust - Stock
I want torque in the bottom end with a good idle basically a sleeper. Does this combo work? I do not understand DCR will this engine run on 91 unlead? What hp would you calulate this specification to yield?
Block - .030 over
Pistons - Speedppro Forged piston L2491F30
Heads - Dart Iron Eagle Heads - 200cc runner 2.02/1.60 valves .550 max lift part # DIE111 9.88:1 SCR
Intake - Edelbrock performer intake
Cam - Comp hydraulic cam # 12-242-2 Duration Intake 224 Exhaust 230 @.5 LS 110 Lift intake .477 Exhaust .48
Carb - stock Qjet
Exhaust - Stock
I want torque in the bottom end with a good idle basically a sleeper. Does this combo work? I do not understand DCR will this engine run on 91 unlead? What hp would you calulate this specification to yield?
Pro
Joined: Jun 2005
Posts: 725
Likes: 1
From: FL.
Whats the compression ratio?
The 200cc heads will need a bit more lift and duration. I think you should bump up the cam a notch..around, int.488 exh.502. A 383 makes better low end than a 350 with the same profile.
Also 750cfm Carb. and Headers. will match better with 200cc's.
Otherwise choose 180cc heads with less cam, and carb. Headers are always a great idea with any engine performance upgrade.
I think Its possible to end up with a dog 383 if it doesnt match up right with 200cc heads.
My 2 cents worth.
Keep us posted..
The 200cc heads will need a bit more lift and duration. I think you should bump up the cam a notch..around, int.488 exh.502. A 383 makes better low end than a 350 with the same profile.
Also 750cfm Carb. and Headers. will match better with 200cc's.
Otherwise choose 180cc heads with less cam, and carb. Headers are always a great idea with any engine performance upgrade.
I think Its possible to end up with a dog 383 if it doesnt match up right with 200cc heads.
My 2 cents worth.
Keep us posted..
Pro
Joined: Jun 2005
Posts: 725
Likes: 1
From: FL.
Thats good compression , but Youll be fine on 91octane still. your weak link for a real nice street Vette is that rear gear. Thats the c3 highway gear. May be easier to get your goals with 180cc heads, with that rear gear...Maybe someone else will chime in with some goods...
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
I had 3.08 gears and stock manifolds with full duals on my 77 with a 383 (see sig). I had a 2,500 stall converter and with that setup the car ran around 14 flat in the quarter at 100 mph. You should really consider changing the converter if you're looking for any off the line performance at all. A mild converter is OK for normal driving.
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 1,089
Likes: 43
From: Native Californian CALIFORNIA
Army
I had 3.08 gears and stock manifolds with full duals on my 77 with a 383 (see sig). I had a 2,500 stall converter and with that setup the car ran around 14 flat in the quarter at 100 mph. You should really consider changing the converter if you're looking for any off the line performance at all. A mild converter is OK for normal driving.
What exactly would raising the converter to a 2,500 stall do for me. Will it still idle? I do not understand this application
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
As for idle characteristics, the higher stall converter you use, the easier it is to achieve good idle, in gear.
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Melting Slicks
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From: Auburndale Florida
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This is for my 383 build up, 2500 stall, 9.7 SCR, 190 cc alum heads, TH400 and 308 gears
Best of luck, Mark
Pro
Joined: Jan 2005
Posts: 535
Likes: 0
From: Southaven MS
1972 Warship.. I went with the Comp Marine Roller, like the XR276 but has a 112 LSA same money at Summit, much cheaper than a custom grind! Should ship this week and have the motor back together next week
This is for my 383 build up, 2500 stall, 9.7 SCR, 190 cc alum heads, TH400 and 308 gears
Best of luck, Mark
This is for my 383 build up, 2500 stall, 9.7 SCR, 190 cc alum heads, TH400 and 308 gears
Best of luck, Mark
Instructor
Joined: Sep 2004
Posts: 182
Likes: 0
From: Brentwood TN
Here's my 383 - idles like stock yet has unreal torque.
- Eagle Street And Strip Rotating Assembly Speed Pro 5.7 Rods with Hypereutectic Pistons w/Teflon Coated Skirts – 9.0:1 compression
Block Prep - Thermal Cleaned,Shot Blasted,Magnafluxed,Bored & Honed .030" over with Torque plates,Square Decked,Align Bored & Honed,Clearanced for Stroker Crank,Balanced.
- Cam - Comp Cams XE256H-10
Gross Valve Lift .447/.454
Duration At 0.006 Tappet Lift 256/268
- Comp Cams Pro Magnum Rocker Arms 1.52
http://73corvetteproject.blogspot.com/
- Eagle Street And Strip Rotating Assembly Speed Pro 5.7 Rods with Hypereutectic Pistons w/Teflon Coated Skirts – 9.0:1 compression
Block Prep - Thermal Cleaned,Shot Blasted,Magnafluxed,Bored & Honed .030" over with Torque plates,Square Decked,Align Bored & Honed,Clearanced for Stroker Crank,Balanced.
- Cam - Comp Cams XE256H-10
Gross Valve Lift .447/.454
Duration At 0.006 Tappet Lift 256/268
- Comp Cams Pro Magnum Rocker Arms 1.52
http://73corvetteproject.blogspot.com/
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 1,089
Likes: 43
From: Native Californian CALIFORNIA
Army
Here's my 383 - idles like stock yet has unreal torque.
- Eagle Street And Strip Rotating Assembly Speed Pro 5.7 Rods with Hypereutectic Pistons w/Teflon Coated Skirts – 9.0:1 compression
Block Prep - Thermal Cleaned,Shot Blasted,Magnafluxed,Bored & Honed .030" over with Torque plates,Square Decked,Align Bored & Honed,Clearanced for Stroker Crank,Balanced.
- Cam - Comp Cams XE256H-10
Gross Valve Lift .447/.454
Duration At 0.006 Tappet Lift 256/268
- Comp Cams Pro Magnum Rocker Arms 1.52
http://73corvetteproject.blogspot.com/
- Eagle Street And Strip Rotating Assembly Speed Pro 5.7 Rods with Hypereutectic Pistons w/Teflon Coated Skirts – 9.0:1 compression
Block Prep - Thermal Cleaned,Shot Blasted,Magnafluxed,Bored & Honed .030" over with Torque plates,Square Decked,Align Bored & Honed,Clearanced for Stroker Crank,Balanced.
- Cam - Comp Cams XE256H-10
Gross Valve Lift .447/.454
Duration At 0.006 Tappet Lift 256/268
- Comp Cams Pro Magnum Rocker Arms 1.52
http://73corvetteproject.blogspot.com/
Instructor
Joined: Sep 2004
Posts: 182
Likes: 0
From: Brentwood TN
The vacuum is fine the car idles at 550 rpms - with just a slight lope
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I have a local builder that has suggested these specs for my car based on 3:08 rearend, TH400 tranny and stock converter.
Block - .030 over
Pistons - Speedppro Forged piston L2491F30
Heads - Dart Iron Eagle Heads - 200cc runner 2.02/1.60 valves .550 max lift part # DIE111 9.88:1 SCR
Intake - Edelbrock performer intake
Cam - Comp hydraulic cam # 12-242-2 Duration Intake 224 Exhaust 230 @.5 LS 110 Lift intake .477 Exhaust .48
Carb - stock Qjet
Exhaust - Stock
I want torque in the bottom end with a good idle basically a sleeper. Does this combo work? I do not understand DCR will this engine run on 91 unlead? What hp would you calulate this specification to yield?
Block - .030 over
Pistons - Speedppro Forged piston L2491F30
Heads - Dart Iron Eagle Heads - 200cc runner 2.02/1.60 valves .550 max lift part # DIE111 9.88:1 SCR
Intake - Edelbrock performer intake
Cam - Comp hydraulic cam # 12-242-2 Duration Intake 224 Exhaust 230 @.5 LS 110 Lift intake .477 Exhaust .48
Carb - stock Qjet
Exhaust - Stock
I want torque in the bottom end with a good idle basically a sleeper. Does this combo work? I do not understand DCR will this engine run on 91 unlead? What hp would you calulate this specification to yield?
Comp Cams has just too many flat cams to be a coincidence. I used the the Crane power max 278 for years with the high intesity lifters with 1.6 roller tips.
Buy a real manifold that does give performance. The Weiand Stealth.
The Performer or lack there of is only good on pickup trucks turning lower rpm - It would really choke a 355 ci. during dyno testing it shut my motor down just over 5000 rpm with a 600 carb. At first i thought it was the carb so I installed a 750 cfm. The Performer sut it down again. the runners are just to small.
Last edited by gkull; Dec 29, 2006 at 05:48 PM.
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 1,089
Likes: 43
From: Native Californian CALIFORNIA
Army
I have a M21 4 spd with 3.70 gears out back... The heads are the stock L82 heads from 73 Casting No 330545 (cast iron) 2.02/1.6" Valves, 76.18cc, tapered spark plug, screw in studs & guide plates with 76cc Combustion Chambers. The heads were pocket ported and gasket matched
The vacuum is fine the car idles at 550 rpms - with just a slight lope
The vacuum is fine the car idles at 550 rpms - with just a slight lope
Instructor
Joined: Sep 2004
Posts: 182
Likes: 0
From: Brentwood TN
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 1,089
Likes: 43
From: Native Californian CALIFORNIA
Army
since you have analyzer 3.3 what changes to your base model could be made to hit 400+hp. Would aluminum heads, etc get you there?
Instructor
Joined: Sep 2004
Posts: 182
Likes: 0
From: Brentwood TN
