Ported E7 Flow Numbers

[Nathan in MI]

Gadget, the combo I ran before seemed to really like the single plane and showed a noteworthy jump (about 50 peak hp, with only a very small drop down low where it wasn't doing much anyway) when I switched it from a dual to a single.

That's an odd quirk of Desktop Dyno. With just about any combination, switching from dual plane to single plane adds about 50 hp. That doesn't mean it would actually happen in the real world. Just slap on a dual plane and go.

[Mr. Land Yacht]

I was advised against the Bcam from a few GMNers including Turbo...it's duration is too high...it's 224* at .050" lift...too high.
So, Mike...that "dyno" sheet is with an E303 cam/1.72 RR...so my exact setup, right? it looks like it...
I wouldn't expect the hp #s to be that high(470ish at 6500rpm) but I would imagine more like 400-420ish....max...but we shall see

[1987cp]

That's an odd quirk of Desktop Dyno. With just about any combination, switching from dual plane to single plane adds about 50 hp. That doesn't mean it would actually happen in the real world. Just slap on a dual plane and go.

Not from what I've seen; some combinations seem to show virtually no change, and low-end-oriented combos seem to generally show a very significant loss. Maybe I'd better have another look at it, though, since you guys know more about the program than I do.

[Mr. Land Yacht]

Now I REALLY can't wait to build it up

[1987cp]

I was advised against the Bcam from a few GMNers including Turbo...it's duration is too high...it's 224* at .050" lift...too high.
So, Mike...that "dyno" sheet is with an E303 cam/1.72 RR...so my exact setup, right? it looks like it...
I wouldn't expect the hp #s to be that high(470ish at 6500rpm) but I would imagine more like 400-420ish....max...but we shall see

So far as I can tell, yeah - the only thing I'm thinking I could have accounted for with more effort is differences in effective duration from the bigger rocker ratio, but that might not be practical to account for in a simple simulation like this one. I'll have to leave that question for someone else. There is the issue of the valve sizes, as according to these simulations, they make a bit of difference. I was assuming 2.02/1.60 valves while Gadget is assuming stock valves, so I'm curious what valves are actually installed.

I was also pretty surprised that DD claimed as much power as it does. I did notice, for example, that the torque output is rather optimistic for a stock 5.0 HO motor, and while the power at the factory-rated horsepower peak is correct, the simulated peak is a little higher up - so right, I'd guess these numbers could possibly be a little optimistic. If the output were known to be reliable, I'd be pretty keen on building the engine, doing whatever is needed to keep it spinning between 3500 and 8000 RPM - probably with some deeper gears and reducing the car's weight some - and see what it does!

[Mr. Land Yacht]

I'm not sure about the valve sizes...We'll have to wait for Turbo to see this thread again
Gerry never said anything about making the valves larger...so I'd assume they are the stock size(whatever that is )

[1987cp]

I think that'd be the 1.78/1.45. I'll keep my eyes peeled!

[Mr. Land Yacht]

adn your ears open

[gadget73]

Mine was run using stock valve sizes and the flow numbers from my particular heads. I don't have the sheet but no real reason to expect it to be much different than yours.

Nate: the effects of the dual plane really vary with the cam. Generally speaking it helps on the bottom and hurts up top but some cams don't work well at low rpms, so the intake really won't change much.

http://www.jason.fletcher.net/tech/camlist/cams_rol.htm if anyone wants the specs on the FMS letter cams and a bunch of others.

[Nathan in MI]

Nate: the effects of the dual plane really vary with the cam. Generally speaking it helps on the bottom and hurts up top but some cams don't work well at low rpms, so the intake really won't change much.

Yeah, I know that's true in the real world, but I was talking about some of the weird stuff Desktop Dyno does. I should dig up the thread on Moparchat that I found that someone posted where he discusses some of the oddities of how DD works.

[gadget73]

yeah its definitely not the most accurate thing on earth. Seems to me some of the numbers it chugs out are somewhat pipe dream-like. Its somewhat useful comparing what a single change would do to the power bands, but it really isn't the final word fo sho.

[Mr. Land Yacht]

btw, when I actually Dyno this car a while from now, is there anyway to find out how much HP I have at the crank?
like some sort of calculation or something?

[1987cp]

Don't people usually assume something like a 15% loss through the driveline? There are probably different figures to use for a manual versus automatic transmission, too, or if you run a harder-to-turn rearend like a 9".

[Mr. Land Yacht]

yea, I always heard 15-20%...I know that someone here dynoed a stock MGM and came out to 129rwhp...which would be only a 14% loss...
so, if I dyno at ~330hp or more(that's somewhere around 17% loss), I will be a very happy camper :banana:

[turbo2256b]

I'm not sure about the valve sizes...We'll have to wait for Turbo to see this thread again
Gerry never said anything about making the valves larger...so I'd assume they are the stock size(whatever that is )

You have the 1.94/1.6 SS valves