Engine rebuild suggestions
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Joined: Jun 2006
Posts: 67
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From: Iowa
Engine rebuild suggestions
I am planning to pull the matching numbers engine out in a couple of weeks and rebuild it. Car is a 1973 coupe, L-48 with auto. I have looked into crate vs. rebuild and I think I want to go the rebuild route. Here's what I have been thinking:
1) Bore as needed and clearance the block for a Scat 383 kit. Of course block will be tanked, new cam bearings, etc...
2) Scat 383 crank and rods
3) Speed Pro Hypereutectic Pistons in the 9.8 range
4) Dart Platinum Iron Eagle heads (need some suggestions here on runner size)
5) Lunati Voodoo Cam & Lifter Kit #60102LK
6) Car currently has an old Torker II manifold and smallish holley. I am open to suggestions here. I thought about going TPI, but not sure I want to drop a couple of grand on that conversion right now.
7) I will probably stay with the Turbo 400 for now but I may swap to a 200R4 in a couple of years.
Of course I will keep the stock crank and heads for the future and I will not have the block decked in order to retain the VIN stamping. What do you guys think of this setup? Any suggestions are welcome.
Thanks in advance.
1) Bore as needed and clearance the block for a Scat 383 kit. Of course block will be tanked, new cam bearings, etc...
2) Scat 383 crank and rods
3) Speed Pro Hypereutectic Pistons in the 9.8 range
4) Dart Platinum Iron Eagle heads (need some suggestions here on runner size)
5) Lunati Voodoo Cam & Lifter Kit #60102LK
6) Car currently has an old Torker II manifold and smallish holley. I am open to suggestions here. I thought about going TPI, but not sure I want to drop a couple of grand on that conversion right now.
7) I will probably stay with the Turbo 400 for now but I may swap to a 200R4 in a couple of years.
Of course I will keep the stock crank and heads for the future and I will not have the block decked in order to retain the VIN stamping. What do you guys think of this setup? Any suggestions are welcome.
Thanks in advance.
Racer
Joined: Apr 2005
Posts: 494
Likes: 0
From: Virginia
I just did an in car rebuild on my 73 - 350, didn't plan it that way, one thing just led to another. It’s running now, still have a lot of work to do. If I had to do it again would definitely go with a crate engine 383 or something along those lines. Too much time and work involved on a rebuild. Drop a crate engine in; quick, easy, and you know it's going to run good (if you pick the right one 
). Good luck.
). Good luck.
Thread Starter
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Joined: Jun 2006
Posts: 67
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From: Iowa
Originally Posted by FAST73
I just did an in car rebuild on my 73 - 350, didn't plan it that way, one thing just led to another. It’s running now, still have a lot of work to do. If I had to do it again would definitely go with a crate engine 383 or something along those lines. Too much time and work involved on a rebuild. Drop a crate engine in; quick, easy, and you know it's going to run good (if you pick the right one ). Good luck.
). Good luck.
Drifting
Joined: Apr 2004
Posts: 1,302
Likes: 36
From: Allen Park Mi
are you running headers or ramshorns?
that will make a differnece in the cam.
i don't know the specs on that voodoo, but the modern tight LSA cams run like crap with manifolds..
i just went through this in my Corvette and my 69 Z28. Both cars have factory manifolds and I went to smaller More modern cams on tighter LSAs and in both cases the cars ran worse... I put OE HI-PO cams back in both (duntov 30-30 to be exact) and the cars both came to life like I coudln't believe, and both cam manufacturers coudln't believe that the Dinosaur Duntov 30-30 ran better... they figured I installed their cam wrong LOL nope.
learned my lesson the hard way.
Aaron
that will make a differnece in the cam.
i don't know the specs on that voodoo, but the modern tight LSA cams run like crap with manifolds..
i just went through this in my Corvette and my 69 Z28. Both cars have factory manifolds and I went to smaller More modern cams on tighter LSAs and in both cases the cars ran worse... I put OE HI-PO cams back in both (duntov 30-30 to be exact) and the cars both came to life like I coudln't believe, and both cam manufacturers coudln't believe that the Dinosaur Duntov 30-30 ran better... they figured I installed their cam wrong LOL nope.
learned my lesson the hard way.
Aaron
Drifting
Joined: Apr 2004
Posts: 1,302
Likes: 36
From: Allen Park Mi
by the way, in a lower compression 383...
i ran the L79 (327-350) hydraullic cam in a 68 Z about 20 years ago..
that car had m-20 wide ratio trans and 3.36 gears and it still makes me smile.
it had stock exhaust, stock intake and holley,
i think it ran 12.50s on street tires back then... which is haullin for stock exhaust and stock appearing.
A
i ran the L79 (327-350) hydraullic cam in a 68 Z about 20 years ago..
that car had m-20 wide ratio trans and 3.36 gears and it still makes me smile.
it had stock exhaust, stock intake and holley,
i think it ran 12.50s on street tires back then... which is haullin for stock exhaust and stock appearing.
A
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
In your case I would buy a donor block and keep your original engine intact. The only thing you would re-use is the block and the oil pan anyway it sounds. You can probably buy a good machined block for around $300 or so. Then you don't have to worry about decking.
Thread Starter
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Joined: Jun 2006
Posts: 67
Likes: 0
From: Iowa
Originally Posted by aaronz28
are you running headers or ramshorns?
that will make a differnece in the cam.
i don't know the specs on that voodoo, but the modern tight LSA cams run like crap with manifolds..
i just went through this in my Corvette and my 69 Z28. Both cars have factory manifolds and I went to smaller More modern cams on tighter LSAs and in both cases the cars ran worse... I put OE HI-PO cams back in both (duntov 30-30 to be exact) and the cars both came to life like I coudln't believe, and both cam manufacturers coudln't believe that the Dinosaur Duntov 30-30 ran better... they figured I installed their cam wrong LOL nope.
learned my lesson the hard way.
Aaron
that will make a differnece in the cam.
i don't know the specs on that voodoo, but the modern tight LSA cams run like crap with manifolds..
i just went through this in my Corvette and my 69 Z28. Both cars have factory manifolds and I went to smaller More modern cams on tighter LSAs and in both cases the cars ran worse... I put OE HI-PO cams back in both (duntov 30-30 to be exact) and the cars both came to life like I coudln't believe, and both cam manufacturers coudln't believe that the Dinosaur Duntov 30-30 ran better... they figured I installed their cam wrong LOL nope.
learned my lesson the hard way.
Aaron
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Thread Starter
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Joined: Jun 2006
Posts: 67
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From: Iowa
Here are the specs on that Voodoo cam:
Advertised Duration IN/EX: 262/268
Duration @ .050 IN/EX: 219/227
Gross Valve Lift IN/EX: .468"/.489"
LSA / ICL: 112/108
Valve Lash IN/EX: Hyd/Hyd
RPM Range: 1400-5800
Advertised Duration IN/EX: 262/268
Duration @ .050 IN/EX: 219/227
Gross Valve Lift IN/EX: .468"/.489"
LSA / ICL: 112/108
Valve Lash IN/EX: Hyd/Hyd
RPM Range: 1400-5800
Instructor
Joined: Feb 2006
Posts: 156
Likes: 0
I would go with the rebuild. My father and I built his motor from his 78 camaro and it was well worth it. There was a great deal of satisfaction when we were finished. Just another point of view on the rebuild vs crate! Good luck!
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
Originally Posted by markdtn
In your case I would buy a donor block and keep your original engine intact. .
I would pull the L-48 and put it aside
Someday you will be glad you did
Plus the downtime is much less with a crate engine.
I would like more guts from my 73 but I refuse to bastardize the original engine to get there because some years down the road it will turn out to be a big mistake
Thread Starter
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Joined: Jun 2006
Posts: 67
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From: Iowa
Originally Posted by Bob Onit
That or a crate engine
I would pull the L-48 and put it aside
Someday you will be glad you did
Plus the downtime is much less with a crate engine.
I would like more guts from my 73 but I refuse to bastardize the original engine to get there because some years down the road it will turn out to be a big mistake
I would pull the L-48 and put it aside
Someday you will be glad you did
Plus the downtime is much less with a crate engine.
I would like more guts from my 73 but I refuse to bastardize the original engine to get there because some years down the road it will turn out to be a big mistake
That said, am I better off with a junkyard casting or should I be looking at the GM clones available from summit or jegs?
Le Mans Master
Joined: Oct 2001
Posts: 5,943
Likes: 3
From: Wildwood IL
Originally Posted by Hogzilla
Here are the specs on that Voodoo cam:
Advertised Duration IN/EX: 262/268
Duration @ .050 IN/EX: 219/227
Gross Valve Lift IN/EX: .468"/.489"
LSA / ICL: 112/108
Valve Lash IN/EX: Hyd/Hyd
RPM Range: 1400-5800
Advertised Duration IN/EX: 262/268
Duration @ .050 IN/EX: 219/227
Gross Valve Lift IN/EX: .468"/.489"
LSA / ICL: 112/108
Valve Lash IN/EX: Hyd/Hyd
RPM Range: 1400-5800
Had one very similar in my '77 350. Woked great!! I'm not an expert, but with your combo, an intake runner size of 190 on the heads would work great. Low rear gear, stock stall, low duration cam, & 190cc runner head will make a great everyday street car with awsome diveabilty and manners. Your build components are similar to the 350 i had, and I could drive that baby anywhere without any issues or special driving techniques or instructions. Get in...fire it up....just go!!!
Good luck
Eddie
Drifting
Joined: Oct 2005
Posts: 1,915
Likes: 48
From: Angier nc
i would pick up a used block.they are cheap and available.the machine shop will check it out.
i would think a 180cc intake runner would be sufficient considering your cam size and compression.you arent turning alot of rpm's and that will keep the air velocity up.
i ran a similar combo in my nova with trick flow alum heads and a comp 280 magnum cam.it ran great.
i would consider switching to a dual plane intake if you are running a stock/low stall converter.if you have the clearance go with an rpm intake or maybe the holley street dominator.
some 3.42-3.73 gears should help her sing!
i would think a 180cc intake runner would be sufficient considering your cam size and compression.you arent turning alot of rpm's and that will keep the air velocity up.
i ran a similar combo in my nova with trick flow alum heads and a comp 280 magnum cam.it ran great.
i would consider switching to a dual plane intake if you are running a stock/low stall converter.if you have the clearance go with an rpm intake or maybe the holley street dominator.
some 3.42-3.73 gears should help her sing!
Advanced
Joined: Nov 2003
Posts: 75
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From: saratoga springs ny
What's up Hogzilla.
I've said and will continue to say it.
Give Mike a call at MASperformance. Have him build your 383. Take your original motor and save it.
Everytime I hear my car start, run , or hear someone else comment on how terrific and healthly it sounds, I smile ear to ear. Feeling the power when I drive it. NICE..
Let me know if you want some details.
Enjoy the decision making process.
I've said and will continue to say it.
Give Mike a call at MASperformance. Have him build your 383. Take your original motor and save it.
Everytime I hear my car start, run , or hear someone else comment on how terrific and healthly it sounds, I smile ear to ear. Feeling the power when I drive it. NICE..
Let me know if you want some details.
Enjoy the decision making process.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
For a 383 I would go nothing smaller that 200cc intake runner and 280ish (advertised) duration cam, if you are putting this motor in an RV or towtruck that cam is fine 
Instructor
Joined: Dec 2005
Posts: 190
Likes: 0
From: Hot AZ
I agree sounds like it would be a good project for you and your son, if he's into it. I'm also with the others forget the L-48, put it away! Why build up that old 2 bolt main, when you can get a new 383 GM block with 4 bolt mains?
GM PART # 88959106 *
CATEGORY: All
PACK QTY: 1 CORE CHARGE: $0.00
GM LIST: $1,014.90
OUR PRICE: $738.85
DESCRIPTION: BLOCK
This bare block is the same as 10105123 except the pan rails have been already machined so the 3.80" crankshaft clears the block. It has 4.00" diameter cylinder bores and four-bolt main bearing caps. This block is machined for a one-piece rear main crankshaft seal. This block weighs 197 lbs. TECH NOTES: Cylinder wall thickness is the same as current production engines. The lifter valley is machined for Hydraulic roller and or flat tappets. Crankshafts with two-piece seal can be installed with adapter part number 10051118.
GM PART # 88959106 *
CATEGORY: All
PACK QTY: 1 CORE CHARGE: $0.00
GM LIST: $1,014.90
OUR PRICE: $738.85
DESCRIPTION: BLOCK
This bare block is the same as 10105123 except the pan rails have been already machined so the 3.80" crankshaft clears the block. It has 4.00" diameter cylinder bores and four-bolt main bearing caps. This block is machined for a one-piece rear main crankshaft seal. This block weighs 197 lbs. TECH NOTES: Cylinder wall thickness is the same as current production engines. The lifter valley is machined for Hydraulic roller and or flat tappets. Crankshafts with two-piece seal can be installed with adapter part number 10051118.