Yet another motor ?
Thread Starter
Instructor
Joined: Aug 2007
Posts: 103
Likes: 0
From: Chatham On
Yet another motor ?
Okay so I have been doing some motor hunts on and off as I was going to do either a 383 or 427 sbc. After some research and debating the 383 seems more appropriate.
I came across a low mile 383 that seemed like a good price even if I decided to change a few things. I am trying to get some additional specs and can update if I get them but this is what I have.
Let me know your thoughts.
383 forged crank and pistons 11.5 to 1
5.7 rods
Hyd roller and roller rockers
1pce rear 4 bolt
High vol pump
87 alum 2.02 ss valve vette heads ported (have a buyer if I want to sell heads)
TBI intake with upgraded TBI no computer
Lift 480 int 492 exh ( no other specs on cam)
Comes with a bunch of extra parts ign ECG
Says 450 hp 1500 to 5500 best rpm range 11.25 to 1 runs on prem pump gas
So how many probs changing to the 1 pce from my 2 I have a 4 gear?
Is there any aftermarket Tbi controller out there if I did not to go back to carb?
I assume they are 58cc heads any idea of possible pistons that are in there -cc or flats maybe as I may want to drop the compression using different heads?
Any other issues you guys see or any thoughts?
Thanks
I came across a low mile 383 that seemed like a good price even if I decided to change a few things. I am trying to get some additional specs and can update if I get them but this is what I have.
Let me know your thoughts.
383 forged crank and pistons 11.5 to 1
5.7 rods
Hyd roller and roller rockers
1pce rear 4 bolt
High vol pump
87 alum 2.02 ss valve vette heads ported (have a buyer if I want to sell heads)
TBI intake with upgraded TBI no computer
Lift 480 int 492 exh ( no other specs on cam)
Comes with a bunch of extra parts ign ECG
Says 450 hp 1500 to 5500 best rpm range 11.25 to 1 runs on prem pump gas
So how many probs changing to the 1 pce from my 2 I have a 4 gear?
Is there any aftermarket Tbi controller out there if I did not to go back to carb?
I assume they are 58cc heads any idea of possible pistons that are in there -cc or flats maybe as I may want to drop the compression using different heads?
Any other issues you guys see or any thoughts?
Thanks
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Well 11.5 to 1 compression and a .480 lift roller cam don't sound right. That much compression will require a 300+ duration cam to run pump gas. Never seen a 300+ duration roller cam with only .480 lift. This means your either being lied to or the owner has no clue what he has. The engine is used and you can't hear it run. All negatives. Why was it puilled? I would be walking away from this deal.
Thread Starter
Instructor
Joined: Aug 2007
Posts: 103
Likes: 0
From: Chatham On
I am too some what sceptical but I have seen many builders quote HP during a build that are way over stated.
I have seen those power levels dynoed before in a similar configuration but not with those heads, generally with 195 or 190 AFR's.
I have quite a few ?s to ask him but with a forged inside the price is attractive.
Can you elaborate on the casting number difference?
Also elaborate on the cam friendly TBI?
I was curious about adding a holley or fast efi controller to a TBI also the 2 to 1 pce rear changes.
Thanks
I have seen those power levels dynoed before in a similar configuration but not with those heads, generally with 195 or 190 AFR's.
I have quite a few ?s to ask him but with a forged inside the price is attractive.
Can you elaborate on the casting number difference?
Also elaborate on the cam friendly TBI?
I was curious about adding a holley or fast efi controller to a TBI also the 2 to 1 pce rear changes.
Thanks
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Too many fluff up #s to sell pieces.
Local big name builder out here does it or did it to a friend of mine..hes convinced his maybe 480hp 347 is putting out 550. cant get him to run me for some reason lol. Hes got his dyno sheet so it must be right? Just like flow #s some are just so full of it and most rarely bother to double check.
Others use different tweaks on their dyno..OR the numbers are right but fresh cool air plumbed into the carb no accessories etc etc. Just build the best you can for usage/budget and the numbers will be what they will be.
If I had to do it again it would have a much smaller HR cam and a turbo with about 10lbs of boost easier to drive and way more power. costs less than a S/C I think
Local big name builder out here does it or did it to a friend of mine..hes convinced his maybe 480hp 347 is putting out 550. cant get him to run me for some reason lol. Hes got his dyno sheet so it must be right? Just like flow #s some are just so full of it and most rarely bother to double check.
Others use different tweaks on their dyno..OR the numbers are right but fresh cool air plumbed into the carb no accessories etc etc. Just build the best you can for usage/budget and the numbers will be what they will be.
If I had to do it again it would have a much smaller HR cam and a turbo with about 10lbs of boost easier to drive and way more power. costs less than a S/C I think
Last edited by cv67; Jan 17, 2013 at 01:07 PM.
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Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
You can't change a one piece rear seal block to a two piece rear seal plus I think the block and crank are unique for each setup. I'd pass this dream deal up. Too many questions unanswered.
Thread Starter
Instructor
Joined: Aug 2007
Posts: 103
Likes: 0
From: Chatham On
I talked the guy, he seemed alright I am very much thinking I should just stay away but in talking to him I have a question more curious than anything.
When he had the build done he said he used a Scat 400 forged crank machined to the 350 size. Also I know this is a 1 pce rear seal block so either Scat makes a crank like that or he used an adapter?
When he had the build done he said he used a Scat 400 forged crank machined to the 350 size. Also I know this is a 1 pce rear seal block so either Scat makes a crank like that or he used an adapter?
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
They make aftermarket 400ci blocks with 400crank mains or 350mains. I have a 4 inch stroker crank with 350main journals in my 400ci Motown block that I also ordered with 350mains. This slows the main bearing speed down and is not a big factor but spinning at 7000RPM there may be some benefit. 
So you can buy aftermarket forged 400 cranks with 400mains or 350mains and you can buy aftermarket 400ci blocks with 400mains or 350mains
Who knows what this engine had done to it but I would stay away from it.
So you can buy aftermarket forged 400 cranks with 400mains or 350mains and you can buy aftermarket 400ci blocks with 400mains or 350mains
Who knows what this engine had done to it but I would stay away from it.