MTFCA Forum

Hi flow aluminum intake manifold... anyone have any experience with one? Pros/cons?

They have worked well for me

We, as in Australia do have a con, it is just wide enough that it has to be removed to get the generator out with the RHD steering in the way.

Only slight con.....at least on my install of the hi-vol intake. The intake flange rim is a bit larger than Ford intake, and with a repro exhaust manifold the hi-vol intake impinged on the underside of the exhaust manifold.

Had to grind off a flat on the top side of the alum hi-vol intake flange rim to nest up, otherwise the intake won't seat on its gaskets squarely.


(New intake powder-coated, and new exhaust manifolds)

My experience is that with everything else stock even bore and stroke stock,and a stock NH carburetor it causes the car to be slow accelerating. It works great at high speeds. I think it is drawing too much air when you open the throttle and not enough suction to draw in gas. Kind of like trying to blow out a candle with your mouth wide open.
I have not tried it with other speed equipment on the car or with a different carburetor, so I would not be against using it if it works with what else you are using.
Norm

I’ve had the same experience as Dan. A little massage with a grinder takes care of it. Didn’t notice any real difference in performance but your experience may vary.

Andy

With those who have rebuilt the engines with a little bit larger diameter valves, 280 camshaft and a straight through NH carburetor will find this large bore intake manifold to be a real positive asset.... These are new castings of an earlier Ford intake manifold.

Thank you!

I have one on my speedster. with a Texas T carburetor(yes the one that requires a fuel pump) I noticed more performance all the way through and top end. very happy with it.

Tim

I have one I have not installed. Someone I respect told me that they improve performance on the top end but you lose out at the low end. One of these days I'll try it out and see for myself but for now I'm happy with the standard intake.

This is one of those rare and interesting things where folks say they work well or don't work worth a darn...and I've come to accept the fact that both things are true. I could give reasons why it should hinder performance and not help, and I'd be right in theory but right in reality only 1/2 the time, and that is a terrible average.

I think the primary differentiator is the condition of the engine and whether or not, performance aspects of the carb and engine have been upgraded - and even at that, I have no doubt that someone could provide dyno test data that shows their stock worn out engine performs better with one.

I'd say you just have to try it and then don't be surprised if it doesn't help and conversely be prepared to congratulate yourself as a genius if it does...it's a coin flip.

I believe a stock or near-stock engine would give up a little low end torque and gain a little higher RPM performance, maybe. That assumes everything is in good shape.

To realize the full potential of a high flow manifold without doing extensive modifications, a high compression head to reduce chamber volume and improve compression and volumetric efficiency would probably be of substantial benefit at all operating speeds.

To really boost power, cam and valve modifications would be needed, along with improvements aimed at increasing reliability at higher engine speeds. A lighter, more streamlined car would benefit more from such modifications than a heavier one, such as a sedan.

I will expand on my experience. I have a RHD 13 touring with a ORIGINAL large volume intake and a Stromberg OF carburetor. Low head. Yes electronic ignition!
The car pulls well at low speeds and climbs hills well and runs nicely at 40 mph
As I don’t have a generator I can’t comment on that situation. It certainly clears the exhaust manifold ok.

Duplicate post.
Read below please.

The intake I saw needed the inside dressed and smoothed out. (Media blasted)
Lots of flakes and scale debris freely releasing from the inside surface, that would be headed to the intake valve of each cylinder.
I wouldn't want to ingest aluminum debris into the motor.

I had the same fitting problem, having to grind away at the top of the alloy manifold. The mounting flange was also a bit asymmetrical , but that is only a cosmetic thing. I fitted a later cast iron big bore manifold, cast in the same way as the original alloy ones, on my tourer. With a straight bore NH Holley it picked up just under two HP on the dyno.

Allan from down under.

I added one when I swapped my vaporizer for a stromberg. The only fit and finish problem I had was the throat casting width at the bottom flange was a little too wide to clear a socket on the mounting bolts. One side cleared the bolt but the bolt on the other side scrubbed the side of the casting. On the plus side, I made a neat wrench with literally only one use! Between the new high compression head, carb and manifold, my coupe runs like a scalded cat.

Brad

Put them on dozens of engines for customers - never had a since issue with any of them.