Blocking off coolant to plenum

[LGAFF]

CCMANO, TOYVET and I did some country driving.....during the course of the drive I got left in the dust by Hans freshly ported intake and headers.....when we got to the car show Hans told me how he had blocked off the coolant to the upper plenum..........also Hans noted that you can now put your hand on the plenum surface and not smell sizzling beef......or in my case more bacony smell.......anyway, the question is, what would the anticipated performance gain be from this mod? Seems this would do well when combined with a relocated IAT, fresh air induction, etc.

Any thoughts? I am not talking 20hp but one would think it would have some impact.

[Aurora40]

I'm bypassing the throttle body coolant, mostly because I noticed white flakey stuff between the TB and plenum, and it turns out the factory gasket corroded. I'm sort of sick of dealing with the crappy TB gasket, so I ordered up a Jerry's one, and I'm gonna go the extra step of bypassing the coolant altogether.

The plenum is probably a bit harder? Doesn't it flow up from the injector housing?

[-=Jeff=-]

I did it too.. not sure there is a performance gain, but i can pull the plenum in 15min without draining coolant..

Pete, Al, Dominic and Hans have this done

[Paul Workman]

Originally Posted by -=Jeff=-

I did it too.. not sure there is a performance gain, but i can pull the plenum in 15min without draining coolant..

Pete, Al, Dominic and Hans have this done

That right there is reason enough to cut it off, IMO!

As far as a performance boost goes resulting from cutting off the coolant to the TB, there is still quite a bit of heat radiating up thru the IH's too; cutting off the TB coolant can't hurt, but that is only part of the story. (There's a lot to be said for those plastic intake plenums used by the LSx motors; very low specific heat values, compared to aluminum.) So, I think a combination of cutting off the TB coolant IN conjunction with a Lingenfelter thermal isolator gasket, might make a bit of sense (or at least Lingenfelter thought so). We can't pack our plenums in ice, less we drown our starters.

I'm gonna dyno mine w/ and w/o the thermal isolator & TB bypass, hopefully sometime this summer. Ideally, I would do a few pulls, then make the swap, and then do some more on the same day, same dyno (the setup at the Mid America Vettefest in September(?) might be one venue for such foolishness).

Anyway...Goood question ya got there! I'm interested too!

P.

[XfireZ51]

Originally Posted by -=Jeff=-

I did it too.. not sure there is a performance gain, but i can pull the plenum in 15min without draining coolant..

Pete, Al, Dominic and Hans have this done

I have the drill and tap if you need it. The brass plugs come from Ace Hardware.
You can pull a plenum in 20 minutes.

[Ccmano]

I've often wondered if the claims made by Ron Woods on his ZR1Products.com site are legit. He claims a 19.8rwhp increase by adding Plenum and Throttle body insulators, Throttle body coolant bypass, light weight underdrive pullies, 145' Thermostat and an X-Pipe. He does post the dyno sheets. Check it out...

http://www.zr1products.com/

I have been considering the insulators.
H

[LGAFF]

Just to be clear, we are not speaking of a TB bypass, but blocking coolant off at the IH.

[XfireZ51]

Lee,

You are blocking off the coolant passage on the top of the injector housing which directs coolant to upper plenum and then to TB. Not the passage between the cylinder head and IH.

[LGAFF]

Yes, I knew that but was amazed at how cool Hans Plenum is now.

[secondchance]

I came accross an interesting calculator that calculates relative horsepower based on air temp, atmospheric pressue and relative humidity:

http://www.anycalculator.com/enginehorsepower.htm

Based on this 100 degree to 90 degree (10 degree differential) holding air pressure at 31 and relative humidity at 30% for both shows 102.2% and 104% respectively - translating to .18% hp differential per degree.

If this is true, for a motor of 350 hp, per 10 degree drop of intake air should result in 6 hp gain roughly.