Aluminium carb spacers (Darin and others)

[Fatman]

Just a quick question for Darin and any others who want to chip in.

Looking at the RM site and notice that some motors use alum carb spacers while other will use a phenolic spacer. Why?

I was always under the impression that phenoilic was a no lose situation.

[LilRacr]

I would like to know more about this also. I like to use phoenolic for heat dissapation but several people have said that there is an advantage in aluminum over phoenolic?

Is this for a specific spacer design? Or false information?

[Darin Morgan]

Just a quick question for Darin and any others who want to chip in.

Looking at the RM site and notice that some motors use alum carb spacers while other will use a phenolic spacer. Why?

I was always under the impression that phenoilic was a no lose situation.

Phenolic has little advantage over aluminum if your under hood temps are not out of site or your engine isn't running at 180-200F. In those cases it can have the advantage of lowering the carb temp but very little if any power is realized from this effort in Drag Racing. Aluminum is easier to machine into the complex designs we now offer. Some of our reversion plates have very thin walls and Phenolic just wont work because its brittle and flakes away when it gets thin in areas. Manifold spacers and anti reversion plates ( don't confuse the two ) where perfected about thirty years ago and I can see nothing new in the industry and have not for at least fifteen years. All these wiz bang spacers and reversion plates have been and where used in Pro Stock and Comp eliminator over twenty years ago. They are nothing new but nobody talked about them or offered them to the general public because they where true speed secrets in the seventies and eighties. The Super Suckers and HVH spacer and Anti reversion designs are not new but they still work just as good today as they did thirty years ago.

Spacers increase plenum volume resulting in more top end power if the engine can utilize it. Its easy to get carried away with plenum volume. You have to be careful not to use to many. The dyno will sometimes show more power by adding two, three or even four spacers. If the plenum volume is to large for the engine it will stall or lag when you shift and fall back into the converter as well as accelerate poorly throughout the entire power band..

Anti Reversion plates help isolate the boosters from the reversion and resonant pulsations in the plenum. This helps increase fuel signal resulting in more fuel flow and air flow. The end result is 6-8hp and in some cases as much as 10-12hp. Only in cases of a very poor engine combination do reversion plates result in HP gains of 20 or more. Some of the claims are flat our lies but we wont go into that.

there are also spacer/anti reversion combination plates that incorporate both into one unit.

[bc]

How do you know when to use an Anti Reversion plate? Or is it just test and see if it helps or not? Also, I see them used alot on tunnel rams, do they benifit a single plain intake also? Who sales the spacer/anti reversion plate combo?

[Fatman]

Thanks Darin

A question along the same lines. What about intake manifold heat?

Is there any advantage to keeping the whole intake manifold cool? I can imagine there would be but why don't we see racers running insulating spacers between the cylinder head and intake manifold? Is this where much heat transfer comes from is is it more from the valley? I guess the condition of the intake charge could be an issue but couldn't you then just tune to suit the cold intake?

Thanks always