Don Terrill’s Speed-Talk

383... 13.5 on alky... 7200 rpms... rules say open spacer only but I'm not opposed to trying a four hole so... Do I go cheap? Fancy? HVH or off brand? Plastic, phenolic, wood or aluminum?

We have been having good success with the HVH spacer line. Particularly the tapered and blended type.
Funny this is that on some combo's we have tested they perform much better up side down which has a base with 4 holes that are blended and tapered into an open side facing up.
I would have to find a party number but they do have some of the best spacers we have used.
There are other notable designs and styles that are for lack of a better way to say this "generic" copies again that showed improvements over the HVH model's.
The intake itself can differ from part to part in the same line out of the box no mods and others that had the full meal deal performed had different results.

I guess what I am saying is working with a specific combo you will ring out every pony in a specific rules engine where part numbers must be used but with all the options for heads post sizes etc available today you just have to test and test some more till you get everything you can from a combo which can be tough without a dyno to do it.
But time slips can also point you in the right direction as well as there are no hard fast rules that you use this spacer with this intake and thats as good as it gets kind of deal

I agree there Pro Power... I hope to book a 1/2 day of dyno time when I'm ready.

I like those super suckers but I've seen some generics have good results too. I guess I'll see if I can pickup a couple cheap ones and maybe find an hvh on the used market so I can compare them.

The sheer plate type never fails to add power and never hurt provided it's on a single plane Manifold.

mag2555 wrote: ↑Sat Jan 20, 2018 7:00 am The sheer plate type never fails to add power and never hurt provided it's on a single plane Manifold.

Single plane...

Rules limit the manifold to 7 1/2 inches from the bottom of the plenum (outside I think) to the carb base. Mine is about 4 1/2 inches... anyone seen an advantage to going three inches high with a spacer?

We had one engine that we had 4 inches of spacer. ! inche 4 hole and 3 inches of open. Made more tq but hp was minimal. But in car didnt run as well and had to go back to 2 in. Had a tendency to back fire.
reed

racear2865 wrote: ↑Sat Jan 20, 2018 9:32 am We had one engine that we had 4 inches of spacer. ! inche 4 hole and 3 inches of open. Made more tq but hp was minimal. But in car didnt run as well and had to go back to 2 in. Had a tendency to back fire.
reed

Funny how that stuff works...

Krooser, i bet the rules are meaning 7.5 inches from the China rail up to the gasket surface ??? Mark H.

swampbuggy wrote: ↑Sat Jan 20, 2018 9:04 pm Krooser, i bet the rules are meaning 7.5 inches from the China rail up to the gasket surface ??? Mark H.

You're right...it's a Wissota rule that also applies for the Dirt Kings Tour. My local track reverts to the Wissota deal too.

It's 7 1/4"... valve galley rail to base of carb. Looks like a 2" spacer is what I need.

Thanks... I missed that.