Plenum size question

[geno]

Did i make this to big? Im thinking of cutting it back and shortening it?

 

[49-blues]

Nice job! Looks great!

 

[Mac in SD]

I hate your guts.

Seriously, that is beautiful.

 

[BlownV6]

Show Off!!! Nice job!!! Mike

 

[geno]

Thanks guys:smile:
I can still cut off the front later and shorten it .I will run it like it is and see how it works. Me and a friend came up with the shape and i cut and fit the pieces and had a guy weld it for me.

 

[Nasty Wendy]

Awe man I hate to tell you this but you screwed that up ROYALLY.:frown:
Being that I'm such a nice guy I'll do you the favor of taking it off of your hands. Consider it my thanks to you for all I've learned from reading posts you've made over the years. I wouldn't have it any other way.

 

[geno]

You might want to learn what not to do from me LOL

 

[John Wilde]

Gene,

That looks sick, run it!

 

[ttypewhite]

I think I just wet myself:redface: Awesome job Geno. Keep up the good work.

 

[laz]

The bigger the plenum the better it looks good just watch the distribution its gonna favor the rear cylinders, if you want better distribution move the throttle body forward this will give the air a little more time to make turns and such, at 250 mph where do u think most of the air will end up?

 

[Nasty Wendy]

The bigger the plenum the better it looks good just watch the distribution its gonna favor the rear cylinders, if you want better distribution move the throttle body forward this will give the air a little more time to make turns and such, at 250 mph where do u think most of the air will end up?

I'm sure he is gonna use a power-plate to correct for that.

 

[John Wilde]

I'm sure he is gonna use a power-plate to correct for that.

That was pretty good!

 

[geno]

The bigger the plenum the better it looks good just watch the distribution its gonna favor the rear cylinders, if you want better distribution move the throttle body forward this will give the air a little more time to make turns and such, at 250 mph where do u think most of the air will end up?

Thanks for your input and i will being watching the exhaust temps with 6 egt,s. Im hoping it will have even boost at the backside of the intake valves because the supply is more than the demand and because all the intake valves dont open at once.Im to stupid to figure out how air moves around inside the intake of a boosted motor. There is alot guys running log style intake with no problems. Ive done some reading on this and most people believe a 90 Deg elbow on a cast intake is the best. If you look at Factory Hogans they are not much better. Ive thought about making a baffle inside to devert air off the rear?

 

[Alky V6]

Ive thought about making a baffle inside to devert air off the rear?

That wouldn't be a bad idea with the shape of the back of your plenum cover. Note how the Hogans are flat in the back. Better yet, the rear should be domed or half mooned a certain distance after the last runner(s). I added a plate in mine to keep flow from bunching up at the rear of the plenum. A simple test I did was to shoot air into the entry and note how much flow I was getting out of each runner on the bench. A very simple, small plate made the flow from each runner much more even.

 

[laz]

Hey i seen alot of different designs and your right alot of the big name custom intakes are not much better kinda like the 2jz supras we got a hogans intake and the distributions horrible the virtual works is way better but 3 times the price . The reason the carb intakes are best is easy to see your pressurizing the middle but aslong as you can monitor and correct with your mangement system your good .

 

[JayC]

The simplest solution is to make a small spacer out of sheetmetal to go between the plenum and intake. Put a small shelf on the back of the spacer that protrudes slightly out into the intake. That will divert the air from ramming the back two cylinders.

I used to make a plenum spacer that Kirban sold for years and that was the premise behind it. It worked well. I dont see any reason that wouldnt carry over to this.

The Hogan intake isnt rounded off in the back. The air pretty much slams into the rear wall and redistributes.

 

[geno]

I was going to make the shelf by skip welding on a lip to the base plate..What do you think about a inch long and kicked down slightly towards the center? Im not trying to set the world on fire like you guys are with your build LOL

 

[JayC]

I was going to make the shelf by skip welding on a lip to the base plate..What do you think about a inch long and kicked down slightly towards the center? Im not trying to set the world on fire like you guys are with your build LOL

I probably wouldnt kick it down but an inch sounds about right.

 

[Alky V6]

These are pics of the plate I'm using. It follows the exact same idea that Jay mentioned. Note how it's angle cut though. I had to do this to get the static flow evened out. One runner on one bank hangs back a bit from the others on a stage I. I'm sure it's the same on a stage II intake. The depth of the plate was important too. I just took a piece of cardboard and taped it to the cover for tests until I had the right shape.

It did make a drastic difference in the flow from each runner. Without it, practically all flow went to the back runners. And I mean ALL.

If I remember correctly, I even think there was a very small flow reversal on the front runners without the plate.

 

[geno]

Ive thought about doing the same thing to my street car with Champion heads and factory Hogans lid Also what do you guys think of the placement of the injector bungs i welded in?