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Discussion Starter · #1 ·
You're the next contestant on
THE HP IS RIGHT !
motor is allmost done and will be dynoed within a few weeks give/take

Guess the hp and torque but you cant go over or you bust lol

Here it is .

Short block :
89 SB 385
Balanced assembly
  • scat 3.75 crank
  • weisco .040 forged pistons
  • scat I beam 6 inch forged pro rod
  • 10.9 CR
Howards /brookshire
31 degree major intensity cam
243 @.050 on a 107
.589 / .589 lift
Isky red zone lifters
crower shaft rockers 1.6/1.5 which puts lift at .628/.589

Afr 195 competition heads
308 [email protected] .600
2.08 valve
65 cc chamber

Hedman 1.75 long tube

Weiand dual plane air gap intake

850 cfm AED anular boosters

Let the bidding begin
 

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Discussion Starter · #5 ·
WAG: 507ft lbs at 4100rpm, 589 hp at 6100rpm
I sure am hopin the rpm stays down there .
I was actually hopin for anything under 65.
I'd love 61 to 63 though because I dont want to run a deep gear in order to be at or near max hp at the stripe .
Trying to walk that fine line where street and strip meet . I'm bordering falling off on the strip side though I think lol. Maybe not
 

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Could you explain why just a 1.5 rocker on the exhaust. I would think getting air out would be just as important as getting air in. I've never understood 1.6's on the intake and 1.5's on the exhaust.
 

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Could you explain why just a 1.5 rocker on the exhaust. I would think getting air out would be just as important as getting air in. I've never understood 1.6's on the intake and 1.5's on the exhaust.
Air comes out under high pressure. This was a common small block thing going back to the Bill Jenkins days. On paper numbers would say you need to increase the exhaust. But even my big blocks have been lift favored on the intake side. This was also proven with my 565 making almost 1000 hp and still using a stock size exhaust valve. I would NEVER recommend changing out any exhaust valve anymore even on stock heads. A set of stock 2.06/1.72 oval port heads, I would go to the 2.19/1.72 combo. Exhaust duration being higher in general is there for the clearing effect to make sure the exhaust is cleaned out by the incoming air at the end of the stroke but this is based on the flow characteristics of the head.
 

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Air comes out under high pressure. This was a common small block thing going back to the Bill Jenkins days. On paper numbers would say you need to increase the exhaust. But even my big blocks have been lift favored on the intake side. This was also proven with my 565 making almost 1000 hp and still using a stock size exhaust valve. I would NEVER recommend changing out any exhaust valve anymore even on stock heads. A set of stock 2.06/1.72 oval port heads, I would go to the 2.19/1.72 combo. Exhaust duration being higher in general is there for the clearing effect to make sure the exhaust is cleaned out by the incoming air at the end of the stroke but this is based on the flow characteristics of the head.
When I asked Jones Cams to spec me a solid roller he too recommended 1.6/1.5 rockers favoring the intake. Also like you said the exhaust duration is greater than the intake. 2.08/1.60 valves

I'm thinking the tight LSA and the dual plane intake ought to knock the peak RPM down a bit but I'm no expert by any means.
 

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Discussion Starter · #10 ·
Could you explain why just a 1.5 rocker on the exhaust. I would think getting air out would be just as important as getting air in. I've never understood 1.6's on the intake and 1.5's on the exhaust.
Look at the heads
 

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Discussion Starter · #11 ·
Joe Sherman said " if switching up intake vs exhaust lift ALLWAYS lift higher on intake and NEVER on exhaust "
When a guy that has had the success of a Joe Sherman makes a blanket statement like that I'm all ears
 

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Discussion Starter · #12 ·
Air comes out under high pressure. This was a common small block thing going back to the Bill Jenkins days. On paper numbers would say you need to increase the exhaust. But even my big blocks have been lift favored on the intake side. This was also proven with my 565 making almost 1000 hp and still using a stock size exhaust valve. I would NEVER recommend changing out any exhaust valve anymore even on stock heads. A set of stock 2.06/1.72 oval port heads, I would go to the 2.19/1.72 combo. Exhaust duration being higher in general is there for the clearing effect to make sure the exhaust is cleaned out by the incoming air at the end of the stroke but this is based on the flow characteristics of the head.
1000 hp out of 565 cubes .
Only a builders builder pulls those kind of numbers off.
What was the torque of that particular motor?
 

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I picked out the parts and built it in my garage. It was machined and dynoed at Jensen Engine Technologies. I had worked in a machine shop building race engines in the early 2000's and this was the last engine I built for the car before getting out of racing.
 

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Discussion Starter · #16 ·
I picked out the parts and built it in my garage. It was machined and dynoed at Jensen Engine Technologies. I had worked in a machine shop building race engines in the early 2000's and this was the last engine I built for the car before getting out of racing.
Man that's quite a build . Very impressive to see those sort of torque numbers out of that many cubes . To me thats what separates the mens from the boys lol

If you had to say what the most influential factor was in getting all that torque out of that number of inches what would it be ?

I know it's the whole combo but ...
 

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I think the longer stroke helped it, and then having a big enough head to support the piston speed. But it was by no means a tow truck motor it made peak torque at 5700 rpm and didn’t vary by more than 10 ft lbs for 1000 rpm from 52-6200.
 

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Could you explain why just a 1.5 rocker on the exhaust. I would think getting air out would be just as important as getting air in. I've never understood 1.6's on the intake and 1.5's on the exhaust.
It's a lot harder to get it in, with nothing but atmospheric pressure filling the cylinder.

On the exhaust side, you've got the ability to open the valve when pressure is still high, and then let the outrushing high pressure exhaust help evacuate itself with the draw it puts on the header pipe and port at the end of the exhaust event.
It not just the rising piston pushing it out, actually the rising piston does very little of the entire exhaust event.

Put bluntly, the intake side needs the help, the exhaust side doesn't....at least on an SBC.

Typically putting the 1.6 rocker on the exhaust hurts low end torque for a slight high rpm gain.
 
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