[charlie66]

Originally Posted by Tom Vaught

You have some good videos out there Charlie.

Tom V.

Thanks.

Tom do you think the round plenum is any more or less better then the square edged one by looking at the two simulations .

Curious about your opinion on this ...

[Tom Vaught]

I could not see the second video Charlie, with the square edged Plenum.
Saw a lot of other Videos of your car though. Way Cool.

The Vortech/Paxton "Power Hat" has a round Plenum and the inlet (located at 7:30) feeding in from that location but many do not know about the "Wall" that is on the other side of the plenum at 5:00 that forces the air entering the plenum to move inward to the center of the carb. They also use a defuser screen to further equalize the air to the carb air horn. Know you have EFI but the air effect is still the same with a round plenum. YOU WILL HAVE A WHIRLPOOL EFFECT WITHOUT THE "WALL" AND THE "DEFUSER SCREEN".

Tom V.

[charlie66]

So if I will have a whirlpool of air, is that going to be bad?

[charlie66]

Originally Posted by Tom Vaught

I could not see the second video Charlie, with the square edged Plenum.
Saw a lot of other Videos of your car though. Way Cool.

The Vortech/Paxton "Power Hat" has a round Plenum and the inlet (located at 7:30) feeding in from that location but many do not know about the "Wall" that is on the other side of the plenum at 5:00 that forces the air entering the plenum to move inward to the center of the carb. They also use a defuser screen to further equalize the air to the carb air horn. Know you have EFI but the air effect is still the same with a round plenum. YOU WILL HAVE A WHIRLPOOL EFFECT WITHOUT THE "WALL" AND THE "DEFUSER SCREEN".

Tom V.

This is the square plenum simulation Tom... https://www.youtube.com/watch?v=MXW_...ature=youtu.be

[Tom Vaught]

Originally Posted by charlie66

This is the square plenum simulation Tom... https://www.youtube.com/watch?v=MXW_...ature=youtu.be

Ok, Thanks Charlie.

Tom V.

[charlie66]

Originally Posted by Tom Vaught

Ok, Thanks Charlie.

Tom V.

Do you have a opinion on which one may be a better choice?

[Tom Vaught]

My old Boss used to say: "Everyone has an OPINION, 10,000 Opinions isn't worth one piece of real data." Build one of the boxes (either one - flip a coin) and get some data and go from there.

Tom V.

[charlie66]

Originally Posted by Tom Vaught

My old Boss used to say: "Everyone has an OPINION, 10,000 Opinions isn't worth one piece of real data." Build one of the boxes (either one - flip a coin) and get some data and go from there.

Tom V.

I understand that Tom. I just respect your opinion and wanted to know it on this ....

[Tom Vaught]

Ok here is how I would do it because I know that this works and gives good distribution to the runners. Do not pay attention to the 'lower runners" or to the runners curved downward. Your runners would be straight into the head ports.

The runners on the top go to the head two runners on each side (just like a 4 cylinder Pontiac cross-ram. Plenum is on the opposite side from the head.

But the inlet tube is on the side of the plenum and bounces the air off the back wall and the the air goes into the runner pairs.

Tom V.

[charlie66]

Originally Posted by Tom Vaught

Ok here is how I would do it because I know that this works and gives good distribution to the runners. Do not pay attention to the 'lower runners" or to the runners curved downward. Your runners would be straight into the head ports.

The runners on the top go to the head two runners on each side (just like a 4 cylinder Pontiac cross-ram. Plenum is on the opposite side from the head.

But the inlet tube is on the side of the plenum and bounces the air off the back wall and the the air goes into the runner pairs.

Tom V.

Thanks Tom.

So you think I should shorten my plenum design like that one> So the inlet is not so far from the back wall like yours?? Mine is 7.5 inches away.

[Tom Vaught]

You can't see the plenum from the side where the runners go into the plenum on top of each other. Like a tunnel ram intake turned on its side.

My point was the T/B runner (from the throttle body) had about a 4" gap from its discharge to the back wall of the plenum. Plenty of room to bang into the wall and then evenly flow to the different runner openings.

Imaging if you took a M/T crossram intake and kept the left side (shown in the pic attached) Those nice straight runners went to the passenger side head for your deal.

Then you cut away the side of the plenum and added a 90 millimeter or 100mm tube from your Throttle Body to the side of the plenum.

You would have a similar intake to the one I posted before.

Tom V.

[Stan Weiss]

Charlie,
Don't know if a v8 manifold picture will help. This was posted by Keith Wilson on a site I am a member of. I don't do Facebook so I don't if there are any better pictures on their Facebook page.

Stan

-------

So just what is the Kool Aid flavor this month?

[Tom Vaught]

Charlie, This link is a step by step thread of how they created a intake very similar to the picture Stan posted (that was provided by Keith Wilson).

The Speed Demon LS Engine uses a intake of the same design and was also fabricated by Wilson Manifolds. It is the fastest non Jet Engine Bonneville Racer.

The link I am providing is a very similar intake done by Wilson and goes thru the steps of why the intake was fabricated the way it was. Enjoy, Charlie.

http://www.lsxmag.com/tech-stories/e...am-for-blownz/

Tom V.

Charlie, If you ever call down to Wilson manifolds and get a chance to talk directly to Keith, tell him I said "Hi"
We go back a long, long ways.

Tom V.

[charlie66]

Originally Posted by Stan Weiss

Charlie,
Don't know if a v8 manifold picture will help. This was posted by Keith Wilson on a site I am a member of. I don't do Facebook so I don't if there are any better pictures on their Facebook page.

Stan

-------

So just what is the Kool Aid flavor this month?

That is the other design I was juggling doing. Just like if you took off 4 runners and half the plenum and turned it on its side . lol

So Stand what do you think of the design I came up with in the simulation? Im not asking you if you know it will work, just your opinion of whether or not you think its doable to try ...

Thank you for the link. im going to look on FB for it..

[charlie66]

Originally Posted by Tom Vaught

Charlie, This link is a step by step thread of how they created a intake very similar to the picture Stan posted (that was provided by Keith Wilson).

The Speed Demon LS Engine uses a intake of the same design and was also fabricated by Wilson Manifolds. It is the fastest non Jet Engine Bonneville Racer.

The link I am providing is a very similar intake done by Wilson and goes thru the steps of why the intake was fabricated the way it was. Enjoy, Charlie.

http://www.lsxmag.com/tech-stories/e...am-for-blownz/

Tom V.

Charlie, If you ever call down to Wilson manifolds and get a chance to talk directly to Keith, tell him I said "Hi"
We go back a long, long ways.

Tom V.

Thank you Tom, Ill read it...

[charlie66]

So getting back to the subject on comparing the change I made in static compression ratio. I made a conversion chart showing what the differences are between 8.4 an 9.8 with boost.. Its starts out where there's around a 5 psi difference between the 2 to equal the same boosted compression ratio. Then as boost rises it eventually grows to almost 7 psi in there comparison . That's where the old 40 is the same as the new 33 psi. But its interesting to me that the change doesn't really show all that much until 27 psi. At the top of the list in the beginning the increase is around .09 of a point. By 27 psi its .86 of a point. Then by the end its 1.92 almost 2 points .. So something is drastically changing at the 27 number.. Another interesting thing is now that im running the car with the change and not just looking at the conversion chart I can tell that the motor gets very angry at an after 27 psi. There's no doubt that it does.. So there's a correlation there confirming some validation of the chart.. From 20 to 25 psi there's a power change but go 2 more to 27 , feels bigger. Yes this is just my a$$ meter so there's no track numbers or anything like that .. I will be going over to the dyno again one of these days though...

Ok so here's the conversion chart I made . I hope it will be of some interest to others as it is to me...

[charlie66]

So if the 9.8 to 1 set up has the same compression ratio at 33 psi as the old 40 psi with 8.4 to 1 what really is different besides the psi being less ?

Will it make more heat and be less efficient or will it be the same ?

Will it need the same timing or will it need less?

It does seem to be at the same power level with 33 psi..

I noticed the fueling demand is the same too.

Seems all the tune stayed the same with less boost..

I'm happy with the turn out....

[GTOGEORGE]

Originally Posted by charlie66

So if the 9.8 to 1 set up has the same compression ratio at 33 psi as the old 40 psi with 8.4 to 1 what really is different besides the psi being less ?

I have a hard time believing that 1.4 to 1 added compression equals 7 lbs of boost. 7 lbs of boost could be anywhere from 140 to 210 hp (just a guesstimate) on a v8. the difference would be added heat with more boost (spinning the blower or turbo quicker) thus making it less efficient, JMO.


GTO George

[charlie66]

Originally Posted by GTOGEORGE

I have a hard time believing that 1.4 to 1 added compression equals 7 lbs of boost. 7 lbs of boost could be anywhere from 140 to 210 hp (just a guesstimate) on a v8. the difference would be added heat with more boost (spinning the blower or turbo quicker) thus making it less efficient, JMO.


GTO George

Its additional 5psi starting at 20. It grew to 7 psi by 33.
My motor made 65 rwhp more with 5psi added.

My real wonder is if it has the same compression ratio at 33 psi as the old 40, is there any more / less or the same heat? It is 7 less psi but with the same cylinder pressure.. So is it a wash or is there more to it? I lean to think if its the same pressure , then with having less psi it might have less heat...

[GTOGEORGE]

Its that 4 cylinder stuff throwing me off! LOL!


GTO George