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Discussion Starter #1
Im currently building a 383 and not being a motor guy i was just hoping to get some input from everyone.

Heres what ive got: 1969 2dr nova turbo350 (art carr built) stock 10 bolt

engine: 350 4 bolt main 1 piece rear main seal block bored 30 over and micro honedclearenced for 400 crank,durabond cam bearings, eagle crank, clevite 77 rod and main bearings, gm o-rods (resized), hyperuetectic kieth black flat top pistons with 2 valve reliefs, speed pro file to fit rings, pioneer high tsi rod nuts, melling high volume oil pump, stock balancer.

Top end: Edelbrock 5087 alum. Heads as follows-2.08 intake,1.60 exhaust valves, 64cc comb chamber,210cc intake runner,62cc exhaust runner. Cam-speed pro #cs-179r or "l79 cam" specs- .050 dur int.222 ex.222, sae duration int.290 ex.290, cam lift int.298ex.298, valve lift int.447 ex.447, lobe centerline 110 int 118 ex 1:5 ratio roller rockers edelbrock victor jr intake 1 5/8 headers, im thinking a 850 holley?

Like i said im not a motor guy so if anybody sees a problem with this combo please let me know! Any one know what the specs would be? Like comp ratio, hp, torque etc? I need some input!!
 

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Im currently building a 383 and not being a motor guy i was just hoping to get some input from everyone.

Heres what ive got: 1969 2dr nova turbo350 (art carr built) stock 10 bolt

engine: 350 4 bolt main 1 piece rear main seal block bored 30 over and micro honedclearenced for 400 crank,durabond cam bearings, eagle crank, clevite 77 rod and main bearings, gm o-rods (resized), hyperuetectic kieth black flat top pistons with 2 valve reliefs, speed pro file to fit rings, pioneer high tsi rod nuts, melling high volume oil pump, stock balancer.

Top end: Edelbrock 5087 alum. Heads as follows-2.08 intake,1.60 exhaust valves, 64cc comb chamber,210cc intake runner,62cc exhaust runner. Cam-speed pro #cs-179r or "l79 cam" specs- .050 dur int.222 ex.222, sae duration int.290 ex.290, cam lift int.298ex.298, valve lift int.447 ex.447, lobe centerline 110 int 118 ex 1:5 ratio roller rockers edelbrock victor jr intake 1 5/8 headers, im thinking a 850 holley?

Like i said im not a motor guy so if anybody sees a problem with this combo please let me know! Any one know what the specs would be? Like comp ratio, hp, torque etc? I need some input!!
What is
micro honed
???
 

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72 Frame off, bare metal resto-mod. 383, TH350, Eaton Posi, Complete new suspension, disk brakes
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Carb a bit much

You are building a pretty nice system there, and should be fun. Based on my research and advice from the folks at Edelbrock, a 750-780is almost on the large size. You can shove so much fuel in there that the engine under-performs. Once you decide on a brand, give their techs a call, they are really good to deal with. Then when the engine has a few miles on it take it to a good racing shop and have the carb jetted correctly for your engine. This needs to be done after the engine is built and the cam run in because each engine has it's own "personality".
You are doing yourself well by asking if you have the right combination to have a good system. Others may also suggest other brands of carb - my son is one of them - so keep an open mind there are some really good ones out there.
 

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You are building a pretty nice system there, and should be fun. Based on my research and advice from the folks at Edelbrock, a 750-780is almost on the large size. You can shove so much fuel in there that the engine under-performs. Once you decide on a brand, give their techs a call, they are really good to deal with. Then when the engine has a few miles on it take it to a good racing shop and have the carb jetted correctly for your engine. This needs to be done after the engine is built and the cam run in because each engine has it's own "personality".
You are doing yourself well by asking if you have the right combination to have a good system. Others may also suggest other brands of carb - my son is one of them - so keep an open mind there are some really good ones out there.
X2^^^
I was thinking same thing! Carb way too large:yes: Like Pete said 750 to 780cfm MAX.

Good Luck with it:yes::D
 

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with a cam that small, I would recommend a performer or performer rpm intake. low end torque will suffer with a victor jr intake :yes:
 

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I'd say go to a little bigger cam(maybe 500 lift and 230-240 duration), dual plane intake instead of the Jr, and 780 max carb. 210 is a good sized intake runner for that small of a cam. compression ratio probably in the 9.75 to 10.25 range. would think you could make 425-450hp. imo
 

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Discussion Starter #10
Thanks for the advice, when i got the motor it had some iron fuel injection heads and a 1986 firebird tpi setup with it. Im using the intake of my old motor, dont really wanna replace the cam! Im installing a power disc brake kit and im afraid if i go bigger it wont have enough vacuum. Glad i didnt buy the carb yet. Thanks again guys! I will be posting some pics soon too.
 

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I agree that 850 is a bit on the large size for that application. I guess I wouldn't be too afraid of a 750-780 cfm carb on a 383 as long as you're geared appropriately and have the correct stall speed converter (assuming you have an automatic). If you run an automatic, you might want to consider a 780 vacuum secondary Holley. The 3310 series was used from the factory on the Z28 302 motor (and other small blocks, as well) and they ran VERY well! In theory, they were over carbed! If you're running a standard transmission, a 750 double pumper would probably be just fine.

I just put together a 385 in a '70 Chevelle with a TH-350 and 3.73's using a 3310, for my neighbor and it runs VERY well! We re-jetted the primaries to 70's and may take them down to 68's now that it's broken in. If memory serves, it came with 71's out of the box. Whatever you end up with, you can do quite a bit of tuning to dial it in.
 

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I understand that I was a little late for the party, but I have some questions

I recently ported a set of GMPP fast burn heads, for a friend of mine, that are going on a 383.
I had a 383 sitting in the shop that had been dynoed with a different set of heads, so I offered to dyno his heads on it to see the power potential of his heads, and to compare to the heads it had already been dynoed with.

We first dynoed his new heads with everything just like the 383 had already been dynoed with. Then we changed out the cam to the cam he plans on running in his 383.

The engine is,
4150 braswell carb,
ported motown intake with 1"" spacer,
GMPP fast burn heads with 2.02""/1.56"" valves with a finished volume of 210cc. (were GMPP vortecs)
1.7/1.7 shaft rockers
flat top pistons with a comp. of 11.5/1
4.031 bore x 3.75 stroke
1 3/4 x 1 7/8 step header, 3"" collector

1st cam dynoed = comp cam 236/248 108 lsa .380in/.367ex lobes.
2nd cam dynoed= Howards shelf cam 255/261 108 lsa, .400 in .413 ex lobe

The 3 columns listed are with the Howards cam at 102*/105*/108* ICL.
When we switched to the bigger cam, peak TQ rpm went up 400-500 rpm, but peak HP rpm was very little higher than with the small cam.

Why? What’s the limit to peak HP rpm on this engine?

What would you change if looking for more power, but no more rpm?

What does the results of these 3 cam position pulls tell us about the engine/cam?

I realize there will be info wanted by some, so just ask.

I can post a pull with the small Comp cam if needed.

Thanks
 

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383

I think with that small cam those heads will kill the motor. That was the problem putting square port big block heads on a low horse motor. Get a cam in the low to mid .500 lift and around 235-240 @ .50 Terery
 

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Should always start with the questions: what are the goals for the car?
210 runner heads are fine with appropriate valvetrain on a 383
But if the goal is just a street car: 170-195cc runners might be ideal
I just accepted an offer for a little 170 cc vortex headed 383.
It’s been in the shop so it needed to go. Little lunati hydraulic flat tappet cam went 12.6 at like 109mph with minimal tuning in a 66 nova.
Has excellent usable torque. Nice little punk street motor.
383’s can make decent power but they can get pricey to do so.
Old technology but maybe we save that for an LS or LT thread.
 

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My solid roller 383 I run the AFR 210 heads and the Quickfuel 850 carb. My buddies 383 hydraulic roller I built him I put the AFR 195 heads and the Quickfuel 750 carb

The 195 heads would be more than enough for that cam. I would put more cam.

Love this one I put in my buddies: https://www.summitracing.com/parts/hrs-110275-10

Needs a 3500 converter and at least a 3.73 gear. Perfect cam for hot street and drive it everyday if wanted.
 

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383 Stroker Build

As stated by others--the cam is too mild & an 850 carb is too much in my opinion. Here's my setup 383---10:1 compression---same heads you have except 55 cc chamber,my pistons have a 10cc dish. I had 1.5 roller rockers on a mild cam like yours. I bought the car with a 383 built by someone other than the previous owner so i measured cam lift myself. Not wanting to replace the cam i had either--i replaced the rockers with 1.6 ratio rollers to bring the lift up to .500---.510. I run a Holley 4160 carb vacuum secondaries 750 cfm with 72s in primary side. My car has vacuum disc brakes & the motor makes plenty of vacuum for those & a nice idle---350 auto trans.---3:73 gears.
So for your setup--try the 1.6 rockers they require .100" longer pushrods to keep the valve train geometry in shape.
 
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