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Discussion Starter · #1 ·
Mild 383, Rochester fuel injection, 58cc aft mkt heads with 2.02/1.60 valves, 3/4 length headers. How would this combination work with a 097 cam?

I know cam technology has improved greatly since 1957, but with the fuelie I’m thinking “ old school”

Just kicking around ideas, so far I have heads, FI unit and headers on another engine.
Thks
 

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Just off the cuff...It seems as if the combustion chamber on those heads are way too small for a 383
 

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1956 chevy 210 del rey sedan
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using 58 cc heads on a 383 even with dished pistons is going to be 11:1 compression. not a great choice at all unless they are aluminum. Honestly you are better off with a 70 cc chamber head and flat tops. the smaller chamber heads shroud the valves really bad and the small valve size chokes the life out of the cubic inches. there is not a super huge selection in pistons for a 383 .
 

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Discussion Starter · #4 ·
Ok, well, scratch the heads! Sorta thought a 4” bore would jack up C/R pretty high. Heads currently on a new 060 over 283, but I think the mtr may be on life support! ……. just in the thinkin stage right now.!
Aside from the heads, what do you think of an 097 in an engine 100” bigger?

Pops, read the sad thread on your “pupper” this am.
They become family!…..a hard pill to swallow for sure. Sorry that happened
 

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Discussion Starter · #6 ·
Thks, mr55/56……..i agree 58cc too small for a 4” bore
 

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Why spend the money to make it a 383 by using small port, small chamber heads and a too small cam? Step up all of those or just build a 350.
 

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I have a buddy that builds motors for customers with some of these new style cams and the finised product dont always run better than my old school stuff,
 

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perhaps he is not the best at selecting a cam?? just sayin.
 

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Discussion Starter · #10 ·
Thanks for the comments……
The 70 LT1’s were 350’s so maybe a cam more along those lines would be a better choice in a 383 build.
Rick, thanks but I’ve been corrected on the 58cc heads and IF I build this I won’t be using these iron heads.
 

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Thanks for the comments……
The 70 LT1’s were 350’s so maybe a cam more along those lines would be a better choice in a 383 build.
Rick, thanks but I’ve been corrected on the 58cc heads and IF I build this I won’t be using these iron heads.
I have a 355 with a Duntov 30-30 with a 69 Z28 intake and carb, that is very fun to drive. It has f/t pistons anb 441 casting 2.02/1.60 72cc heads with screw in studs & guide plates.
 

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Absolutely no argument from me on this point!!!
Should we assume your 383 is set-up for a roller cam or not?
 

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Discussion Starter · #14 ·
IF I do this I’m NOT leaning toward a roller.
Remember this will be with the 63 FI unit I have. As you know vacuum is everything to these units. As Jim Lockwood stated “ the more vacuum the better”. That’s why I asked about the 3737097 cam. Those cams, I’m told, could produce 18-20” of vacuum and of course that was the FI cam back when these cars were built. (64/5 Corvettes had the 30-30 more radical cam)
Plus the “clickity clack” is kinda neat, too. Just don’t know how that cam would react in a 383, but vacuum is something I have to strive for.

tell me if I’m all wet! I do appreciate the comments, good & bad.
 

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Roller cams and high vacuum are NOT mutually exclusive. The factory cam that makes the most vacuum is the roller cam from 80s/90s TBI and TPI engines. Of course it is a rather small cam as for duration and lift.

One thing that makes big vacuum is wide lobe centers, 114° and up. That's what most factory cams have.
 

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GM used a 58cc head on a 4" bore 350 for years (see the Z motors from the 90's to at least the mid 2010's)...decades actually so the notion that a 58cc chamber is a problem in and of itself is bunk. It's not the combustion chamber size that is the problem...they have smallish valves for a 383...but for a 350 they're fine (they used 1.94/1.5 valves like so many other 350's used). They're not great by any means but they did work and were remarkably better than the crap GM put on 4" bore 350's in the 70's and most of the 80's.

If it were me, I'd look at the Trick Flow Specialties 175cc aluminum double hump replica heads for a fuelie build like this. Otherwise, the AFR 180cc head is likely the best head outside of a GM production head that will need a complete rebuild.
 

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Discussion Starter · #17 ·
GM used a 58cc head on a 4" bore 350 for years (see the Z motors from the 90's to at least the mid 2010's)...decades actually so the notion that a 58cc chamber is a problem in and of itself is bunk. It's not the combustion chamber size that is the problem...they have smallish valves for a 383...but for a 350 they're fine (they used 1.94/1.5 valves like so many other 350's used). They're not great by any means but they did work and were remarkably better than the crap GM put on 4" bore 350's in the 70's and most of the 80's.

If it were me, I'd look at the Trick Flow Specialties 175cc aluminum double hump replica heads for a fuelie build like this. Otherwise, the AFR 180cc head is likely the best head outside of a GM production head that will need a complete rebuild.
Thanks, hutchenc, yes I really like the looks of those Trick Flow heads, but from the flow of comments I felt the chambers may be too small for a 383 w/FI.
I think the Trick Flows are 60-64 cc or something like that????
Thanks again
 

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it's not so much the chamber size as it is where the compression is going to end up at and the fact that the valves are small and really shrouded by the chamber. horrible flowing actually.
 

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Discussion Starter · #19 ·
it's not so much the chamber size as it is where the compression is going to end up at and the fact that the valves are small and really shrouded by the chamber. horrible flowing actually.
You guys know much more about this stuff than I do but 2.02. & 1.60 are about as big as one can get in a sbc head ( with race exceptions). Also don’t understand what u mean “ it’s where the compression ends up at”. I would think compression would be equal or nearly so, across the combustion chamber at or near TDC with a flat top piston??
Educate me …… thks on advance
 

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2.02/1.60 Valves were the biggest ever offered in a production car. The only non Corvette to have them after 1970 was the 1974 and back Z28. I would use a dish piston in a 383 with the 60cc Trick Flows. I have them on a flat top 327 and its 9.6-1. A 383 would be much higher.
 
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