A 750dp body and metering blocks with an 850dp baseplate is an 830 right?

Do the venturies have to be opened up to the larger throttle bores? Is the choke horn/tower milled to achieve 830 cfm of flow? I have downleg boosters on my 750....are annular needed? What other mods are necessary for this conversion?

I have read in this forum that the smaller venturies are more sensitive and the throttle response is much improved over an 850dp. Would this be a good swap on a 468 turning 6500rpm or will the loss of 20cfm be detrimental for performance?

TIA

It's the other way around, an 850 body with 750 plate.

The 850 has 1-9/16 venturis and 1-3/4 blades

The 750 has 1-3/8 v's and 1-11/16 blades

The 830 has 1-9/16 v's and 1-11/16 blades

I don't know what you'd get with what you suggested. Might be an interesting experiment. If you do it post your results.

750 body and 850 base plate equals a 950....go figure. It will only flow 830 but holley calls it a 950. yes you will have to blend the body to the base plate.

So which one should I try? The 850 with the 750 baseplate or the 750 with the 850 baseplate?

I have a both the carbs and an extra 750 body.

Which combo do you guys think will be better?

Never was able to figure out why Holley calls their 830cfm HP series a 950 :confused:

I had my carb guy Ty at TPCracing change my 750 to a 950. It works great. I think if I were to do it..I would use a proform body.

Originally posted by bigjimzlll:
I had my carb guy Ty at TPCracing change my 750 to a 950. It works great. How much he charge ya?

Did he just enlarge the venturi opening to 1 3/4 or did he also do some meetering block work to better dial it to your engine?

hes a sponsor...so it was a 150 bucks. That was with a new billet base plate. He recalibrated it too. New boosters too.
http://www.tpcracing.com/testimonials.html

Annular boosters?

Wow that's not a bad price at all with new boosters,a billet baseplate, and some calibration adjustments.
Not bad at all.

Originally posted by novaman:
Annular boosters? No, some sort of a special deal..heres a quote from his web site "Jim recently sent us his Race Double pumper back for a re-calibration to his new motor combo and gained even more E.T. Ty installed his infamous double cut drop-leg booster to enchance the signal of Jim's TPC Stage 3 Racing carburetor."

bigjimzlll,

Shall go ahead and try out both these mongrels (750/850baseplate & 850/750baseplate). I will be using the stock dogleg boosters however. Later on I might upgrade to a Proform body with adjustable air bleeds as you suggested.

Pat Kelly,

Will definitely post the results.

Thanks guys!

Originally posted by bigjimzlll:
</font><blockquote>quote:</font><hr />Originally posted by novaman:
Annular boosters? No, some sort of a special deal..

Ty installed his infamous double cut drop-leg booster to enchance the signal</font>[/QUOTE]The Carb shop does the same mod.I think they would cost a bit more though.