Fred SS

iTrader: (3)

Hey guys, since the TPI plenum is located right above the motor and subject to radiant heat. Would it be worthwhile to coat the bottom of the plenum with some sort of heat reflecting coating or possible heat reflecting tape to reduce heating of the incoming aircharge. I've oredered a IAT relocation kit today and thought maybe I should go further. Maybe the air is not in the plenum long enough to get heated. What do you think?

Oh and I wanted to thank the members of this forum for all the information I gained from reading their posts. The information helped me greatly with my TPI conversion on my 87 Monte Casrlo SS.

Tuned Performance

iTrader: (92)

Gm has found painting engines in black dissipate heat. As far as making the mat to a iat your car will run rich unless you recalibrate if you are running sd for maf tpi it does not seem to effect fuel ration but is used to control egr and air pump.

Fred SS

iTrader: (3)

Thanks for your help Brian. So your saying that moving my Manifold Air Temp Sensor to the intake track ahead of the MAF sensor will require me to re-cal the ecm because the cooler air there will result in the ecm adding more fuel? I guess I'll be selling that kit as soon as I get it. Do you think blocking heat from underneath the plenum is worthwhile. There are several types of heat reflecting tape and coatings that I could place on the underside of the plenum. The reason why I ask it that I know cooler air going into the engine gives more HP, and that plenum gets pretty hot.

cuisinartvette

In theory it sounds good but honeslty wouldnt waste a penny on it youllnever notice any differerence

Tuned Performance

iTrader: (92)

Fred if your running speed density you would need to recalibrate the setting in the eprom for the relocation is will effect the air fuel ratio. On tpi maf its just a waste of money. I don't think you can do much about cooling down the plenum its a heat sink bye design.

ninetyone

iTrader: (2)

You will notice a little difference. Car will be smoother especially when it's already warmed up or engine is hot. I noticed a big decrease in mileage though. This is because the tables need to be reprogrammed in the prom now to compensate for the IAT sensor being moved into the air intake instead of the plenum. The IAT now becomes a MAT sensor.

Fred SS

iTrader: (3)

Thanks guys for all your helpful comments. It'a an 89 MAF TPI system on a 350 chevy, installed in my 87 Monte Carlo SS. Your all probably right, trying to block heat from the plenum is a waste of time. The plenum is a heat sink anyway you look at it.

ninetyone

iTrader: (2)

....and don't forget the actual temperature of the air entering your heads comes from the plenum. You probably want to leave that mod alone.

Tuned Performance

iTrader: (92)

Buy lots of ice bags

Guest

Nitrous, your car will run beast even AFTER the shot. (as it will still be cool in temp)

Tuned Performance

iTrader: (92)

I wish Mrp still made the plenums That would be neat to have.

Fred SS

iTrader: (3)

[quote=Tuned Performance;5555271]I wish Mrp still made the plenums That would be neat to have.

Brian, I,ve never heard of MRP. That plenum looks to be some sort of composite with threaded inserts. I would assume pretty rare.

Tuned Performance

iTrader: (92)

it is very rare I have only seen 1 and don't think very many were produced. Would be neat to see the Dyno results and heat loss. I have heard they made runners as wel but have never seen. Picture of them.

Twin_Turbo

iTrader: (25)

Those things were a piece of junk, that must have been what.. 20 years ago? They made the palstic plenum and the tB. Reports of the thing coming apart, the thhrottle blade stickign in the housing etc. etc. MRP went belly up pretty quickly. Probably because of all the issues

Tuned Performance

iTrader: (92)

the idea of a composite plenum is a good idea, but the throttle body looks like it belongs on a model engine. Yeh I think it was more than 20 years ago my love of gm mpfi goes way back the mechanical Rochester unit looked cool too. Some guys have all the McFarland toys lol