Holley strip dominator intakes

[mike ramirez racing]

can anybody give me some insight/history on the different strip dominator intakes for a sbc? Anybody use any one of these intakes? what works for what sbc application?

I have an older one 300-2 somebody told me its for a 4 speed engine.

There is a 300-25 thats has taller runners for automatics?

and the 300-100 looks like a 1" spacer has been cast integral to the intake.

Any info is greatly appreciated.

[dragrcr71]

I've got an old 300-2 in the basement. It ran about the same as a Vic Jr. on my high 10 second 355 @ 7000rpm with a PG.
The 300-25 does have taller runners. I expect that just moves the rpm range up a couple.

[mike ramirez racing]

anybody else?

[407SBC]

I tried a 300-25 strip dominator vs a 2925 super vic on a 406. Both intakes were lightly ported. The supervic murdered the strip dominator up to about 6000 rpm. From 6K to 8K the strip dominator destroyed the supervic. I really like the strip dominator and dont think it gets much play, especially when you consider the price. Its just about the cheapest 4bbl intake for sbc. The 100 is the one designed with Keith Dorton. Never tried it but would like to.

[want-a-be]

I had an old 300-25 that I welded the runner extensions into the plenum much like the 2925 super vic has. It out performed the super vic accross the board. Did the Mod before the 2925 had hit the market. That intake has picked up every engine it has been on. It's on a circle track car now and he won't even discuss selling it.

With the right plenum mods the 300-25 in hard to beat, imo.

Don

[GOSFAST]

I had an old 300-25 that I welded the runner extensions into the plenum much like the 2925 super vic has. It out performed the super vic accross the board. Did the Mod before the 2925 had hit the market. That intake has picked up every engine it has been on. It's on a circle track car now and he won't even discuss selling it.

With the right plenum mods the 300-25 in hard to beat, imo.

Don

Still holds true today, that "mod", lengthening the runnings along with some very minor "massaging", is worth an add'l 30+ HP from that intake, tested on 355" SB's! Torque numbers were greatly improved!

It still out-performs many of todays manifolds "across-the-board"!

We still use a number of these "Strip-Dominators" on the BB's also, most recently on a 509", 10:1, "990" heads, and making 640 HP. The "older" castings with the "Winters" snowflake seem to have a slight edge and were a "cleaner" casting!

Thanks, Gary in N.Y.

P.S. We picked up in the neighborhood of .3 at the track/30 HP on the dyno (nominal)! Below here is one in the works, "fins" in place, waiting to be finished!

[407SBC]

Beautiful work on that plenum. It must be a pain in the a$$ to weld those runner extensions on. I dont think I would even try. How long does it take you?

My only complaint with the strip dominator manifold is the lack of rear coolant outlets. When I tried to drill them on the bungs that holley puts there they come out offset from the coolant exit in the head. There isnt enough material for a 1/2" npt unfortunately. Its not a crazy big deal but its more work for me to add -12 outlets that I want.

All in all an excellent manifold. Im glad to see others have had the same positive experiences. I havent actually met many people who run these on their cars.

[want-a-be]

Yep,...thats what it looks like when the job is done. Still my preferred intake when this is done to the intake. Not tried a turtle yet but I'm betting the numbers would pick up even a bit more. The numbers you saw on the dyno are pretty much what I saw also. I did do the before and after test.

Don

[mike ramirez racing]

Wow that's great info gentlemen thank you. So far I lost out on a 300-25 and a 300-100 on ebay. I have a 300-2 and was thinking of trying it with a 1" 4hole super sucker. If all else I put up on ebay. Just bead blasted it and painted it cast aluminum. Looks nice.


Just curious...how does the 300-25 compare to a bowtie intake?

[cv67]

Also wondering if a super sucker could help

Are you guys buying or making those runner extensions?

Is that the tradiditonal shape to use, seen others that were straight up and down some at an angle etc. Looks fun to experiment with. You could always tack then in if they didnt work no big deal to remove

[900HP]

I just got this 300-100 from Chad Speier. The "Keith Dorton" model has slightly smaller runner cross section for use with stock unported iron head rules and is also taller as noted previously. It also has provisions for rear water accessory and the carb pad is flat not angled. I haven't put this one together but I'm expecting good things.

[Walter R. Malik]

anybody else?

There were 2 different -2 intake manifolds; the later, (improved? ones), have much shorter runner dividers at the top.
The -25 is the same SIZE runner as the early -2 however, it has a runner length about .900" longer.