I was just going to mention, nitrous does cool down the intake
CK5
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94 Z28 coupe
- Thread starter Bent77
- Start date
Tell us again why its not getting a cam and a supercharger?
That said, I do already have a 373 gear set
I also already have a ZZ 4 camshaft, would have to grind the nose relief and change the drive pin for the opti Spark
I also have the converter that came out of the 700r4 that was in the 69 Camaro so that would raise my stall speed up about 800 hundred RPM
But it’s a good car not some Hoopty piece of shit and I don’t really wanna screw it up
I also already have a ZZ 4 camshaft, would have to grind the nose relief and change the drive pin for the opti Spark
I also have the converter that came out of the 700r4 that was in the 69 Camaro so that would raise my stall speed up about 800 hundred RPM
But it’s a good car not some Hoopty piece of shit and I don’t really wanna screw it up
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Ok, are trying to compete with @ktmoutfront ?
Or are you dictating to your phone.
Did you read what you posted?
Let’s talk cam changes, if nothing else but theory
Most stock sbc cans are lame. As are the heads. So our understanding of power output must consider flow
A stock standard average is about 180 cfm. And trust me that’s with a tail wind
These heads and vortec heads are 200 or 210 based off most flow sheets I’ve seen
Most SBC blocks are 9ish to one. This is 10.5:1
Stock cam
202/207 450/460 117
Option 1
paceperformance.com
Option 2
Most stock sbc cans are lame. As are the heads. So our understanding of power output must consider flow
A stock standard average is about 180 cfm. And trust me that’s with a tail wind
These heads and vortec heads are 200 or 210 based off most flow sheets I’ve seen
Most SBC blocks are 9ish to one. This is 10.5:1
Stock cam
202/207 450/460 117
Option 1
10185071 Hydraulic Roller Camshaft -G.M. ZZ4 Crate Engine
Pace Performance offers the best pricing on products offered by Chevrolet Performance Parts. Including 10185071 - Hydraulic Roller Camshaft -G.M. ZZ4 Crate Engine.
paceperformance.com
Option 2
Pardon Our Interruption
www.summitracing.com
So how much would we gain? Expected power output?
@folkenheath
@6872xtc these are the same 2 cams that you asked me about. Comparison wise this is very relevant to all the questions you asked me
@folkenheath
@6872xtc these are the same 2 cams that you asked me about. Comparison wise this is very relevant to all the questions you asked me
Here’s some factory cam numbers
Not sure I buy the output numbers. Also remember the change in the rating system
The “300” hp 327 cam is what was stock for most all small blocks. I’d rate those 180hp as installed
www.jalopyjournal.com
Not sure I buy the output numbers. Also remember the change in the rating system
The “300” hp 327 cam is what was stock for most all small blocks. I’d rate those 180hp as installed
Technical - GM factory cams - specs
I see a lot of cam threads with general suggestions such as Duntov cam or L79 cam, usually without real info on specs. I spent a little time...
A simple rule of thumb I use to guestimate HP potential at the crank for most 2 valve per cylinder V8s is to use the single intake runner flow of the heads at the valve lift you are using, and double it. So if you want to see a difference, look at the head flow chart and see how much more flow you get, if you are picking up 10 cfm with the increased valve lift, you can guess 20 HP, etc.
This assumes everything else is correct and is just an estimate, but it gets you pretty close quite often. It would not work well to show the difference between a cam that has the same exact lift but more duration, and it won't show higher compression. For that I use a simple chart out of a book. It also assumes you have good head flow data for your heads, proper fuel and ignition timing, good exhaust flow, etc. Obviously don't use the flow at .700" if you only have .500" lift.
If you are adding boost my app estimates HP potential for a supercharger or turbo application. You could also use that to estimate a NA engine with 0 boost, it is going to be heavily dependent on the VE number you use vs actual for the results, which is another guess, but it also estimates based on peak RPM. which you could raise up a few hundred RPM for a change in duration.
This assumes everything else is correct and is just an estimate, but it gets you pretty close quite often. It would not work well to show the difference between a cam that has the same exact lift but more duration, and it won't show higher compression. For that I use a simple chart out of a book. It also assumes you have good head flow data for your heads, proper fuel and ignition timing, good exhaust flow, etc. Obviously don't use the flow at .700" if you only have .500" lift.
If you are adding boost my app estimates HP potential for a supercharger or turbo application. You could also use that to estimate a NA engine with 0 boost, it is going to be heavily dependent on the VE number you use vs actual for the results, which is another guess, but it also estimates based on peak RPM. which you could raise up a few hundred RPM for a change in duration.
We always used that as well
1.9 for flat tappet
2.0 for hyd roller
2.1 for solid.
Fairly close on all the engines we dynoed
So how do you know how much cfm is gained on a can change with no way to test it?
You take thee head flow chart and look at your cam lift.
So for example here are some mild Brodix IK heads..
For the IK200, If you only had a .400 lift cam they are only flowing 230 cfm, or 460 HP potential. (that's probably optimistic though, that's a small cam)
If you step up to a .600 lift cam, that's a 260 cfm, or 520 HP potential.
Or put another way, you could gain 30 cfm or 60 HP.
If you only went from a .550 t0 .600 lift with that head, you are only gaining maybe 4 cfm, or 8 HP. Now, if you have a high flowing head that picks up a bunch between .500 and 600 lift, then you would see a bigger difference with the cam swap.
Obviously this isn't exact, just ball park stuff.
So for example here are some mild Brodix IK heads..
For the IK200, If you only had a .400 lift cam they are only flowing 230 cfm, or 460 HP potential. (that's probably optimistic though, that's a small cam)
If you step up to a .600 lift cam, that's a 260 cfm, or 520 HP potential.
Or put another way, you could gain 30 cfm or 60 HP.
If you only went from a .550 t0 .600 lift with that head, you are only gaining maybe 4 cfm, or 8 HP. Now, if you have a high flowing head that picks up a bunch between .500 and 600 lift, then you would see a bigger difference with the cam swap.
Obviously this isn't exact, just ball park stuff.
That makes my 8.2 diff seem quite adequate!
Directly related to actual traction as well
Then add shock load…
So here’s some lt1 head numbers
Food for thought:
These are close to what vortec heads do. Those heads are limited to .450 lift at the guide, so they never actually reach peak flow
Stock sbc heads flow about 180cfm @.500
LS heads flow more, and is part of why the torque curve is higher
Food for thought:
These are close to what vortec heads do. Those heads are limited to .450 lift at the guide, so they never actually reach peak flow
Stock sbc heads flow about 180cfm @.500
LS heads flow more, and is part of why the torque curve is higher
Let’s talk cam changes, if nothing else but theory
Most stock sbc cans are lame. As are the heads. So our understanding of power output must consider flow
A stock standard average is about 180 cfm. And trust me that’s with a tail wind
These heads and vortec heads are 200 or 210 based off most flow sheets I’ve seen
Most SBC blocks are 9ish to one. This is 10.5:1
Stock cam
202/207 450/460 117
Option 1
10185071 Hydraulic Roller Camshaft -G.M. ZZ4 Crate Engine
Pace Performance offers the best pricing on products offered by Chevrolet Performance Parts. Including 10185071 - Hydraulic Roller Camshaft -G.M. ZZ4 Crate Engine.
Option 2
Pardon Our Interruption
www.summitracing.com
I like that both are 112 LSA versus the 117 you currently have. Either should give some more low end snap.
Between the two I like the hot LT4 cam a bit more. Craptastic GM heads the exhaust flows terribly, so more duration on that side of things is helpful, and the LT4 cam gives you more exhaust duration even though the lift is a bit less.
