Intake porting questions

[plinker]

I pulled the air intake and injection manifold off my truck ('89), Mostly to see what shape everything was in, and to put in injectors, gaskets, clean everything ete..

I read that port matching the intake and the manifold is somthing possibly worthwhile doing. I know porting for 2 cycle engines is beveling the edges of the port, is that all that would need to be done or am I missing something?


Also, do you gain anything HP or MPG wise with plenum and/or throttle body spacers?

 

[IMenriched]

I pulled the air intake and injection manifold off my truck ('89), Mostly to see what shape everything was in, and to put in injectors, gaskets, clean everything ete..

I read that port matching the intake and the manifold is somthing possibly worthwhile doing. I know porting for 2 cycle engines is beveling the edges of the port, is that all that would need to be done or am I missing something?


Also, do you gain anything HP or MPG wise with plenum and/or throttle body spacers?

yes...port matching is just that...removing or blending the two mating surfaces/ports so that there is not a air dam effect. don't think you're missing anything.

as for the plenum spacer....maybe some, but it would be so small that you wouldn't really be able to tell. It would be more for insulation value, trying to keep the air charge as cool & as long as possible. The throttle body (TB) spacer in all likelihood...is just make your wallet lighter.

keeping the whole upper intake cooler makes more sense to me, than just the TB .....but how it going to affect the air charge temp sensor and its information feed back might adversely negate any of the possible gains.

 

[Big Jim M]

Howdy Plink

I pulled the air intake and injection manifold off my truck ('89), Mostly to see what shape everything was in, and to put in injectors, gaskets, clean everything ete..

I read that port matching the intake and the manifold is somthing possibly worthwhile doing. I know porting for 2 cycle engines is beveling the edges of the port, is that all that would need to be done or am I missing something?


Also, do you gain anything HP or MPG wise with plenum and/or throttle body spacers?

For normal driving and normal use your answers are all no!

Port matching: Can be of help to an engine that is running above your power band. When trying to get the last possible tiny bit of flow at extreme high rpm. When using the engine as built for normal requirements..no gain!

Spacers.. It is a well known fact that changing the length of the plenum runners can contain the standoff and maintain velocity at certain rpm at the cost of other rpm. So adding spacers of certain lengths will HELP at certain rpm. However this gain causes a loss at all other rpm. These spacers must be aded to the individual runners and not the plenum itself. The aftermarket spacers being sold for our rides are pure JUNK.. Nothing else.
Big Jim

 

[Irokranger93]

biggest cold air intake