I had a 750cfm mighty demon annular blower carb before. It ran pretty good (had to jet up about 15sizes) but it made decent power on dyno. After about 6months of use two boosters fell off of the main body. I ended up returning it to jegs and used the money to order a custom built carb from pro-systems. The new carb is suppose to built to match my engine combo, weight, and gearing perfectly. The float and idle were suppose to be set or very close. The new carb is no longer boost referenced and flows 785cfm. I was thinking of a 950hp holley but the carb guy said with a stick shift trans to stay smaller on CFM. the new carb also has stepped dog leg boosters instead of annular.

I bolted it on and found the idle was at 1800-2000rpm so I had to adjust the two butterfly screws down to 900rpm. Then I checked the float levels and found the secondary level at the top of the bowl. So Adjusted the float levels to the recommended level. Test drove it and it ran smooth and nice at cruise, i noticed my wideband showing 11-12 AFR at cruise so its rich at cruise. I did a few test runs at WOT and was a little disappointed, the car didnt pull nearly as hard as it used too when old carb was set up correctly. Then I saw the AFR was leaning out to 13.5-14.1.

So much for perfectly tuned/bolt on and go carb lol, I guess I have to jet up on the secondary side. It looks nice though

 

the pics are nice but a audio of that motor would be great.

 

Beautiful carb, but I'm surprised anyone would offer a mail-order carb that was supposed to run anywhere near "perfect". There's way too many variables that a carb simply can not compensate for mechanically without the intervention of a skilled tuner.

 

Way to many variables involved. Would be nice in a perfect world though

 

Here are the specs:

adjustable air bleed system
HP series body
non-stick gaskets
drag float with jet extensions
billet baseplate
stepped dog leg boosters
hi-flow needle and seats
big sight glass bowls

"comes with complete wet-flow porfolio ( jetting is usally dead on or within 2 sizes)

We even set the idle....just bolt on and go. Each carb is built and flowed custom on wet-flow bench to match a custom fuel curve for your exact setup. typically these carbs make 20-35hp over an off shelf unit "



It came with sheet showing all the air bleed and jet sizing and a set of blank air bleeds in case I need to make a change. I need to get the WOT down in the 11.5-12.0 with the blower so I probably need to go up about 4-5 jet sizes on the secondaries.

 

dont have a new video with the new carb, but I have one from few months ago. Its a quick burnout 1st-2nd at my buddy shop "1st burnout of spring 2011"

click on pic
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Saw the burn out. Impressive, beautiful. I bet it WAS a nice set of tires

 

Good for you! I've been sold on Pro-Systems doing the carb for my 427 makeover ever since first researching them. If they're as good as appearances, I may never buy a carb "off-the-shelf" again.

 

Sounds awesome.

 

sounds like a vette is suppose to

 

That is one Wicked Vette.... (with a proper diff!)

 

Thanks man!

 

I had a chance to tune the car today and it made a huge diff. I went up 4 jet sizes on secondary side and 2 on primary side. Then I adjusted the 4-idle mixture screws, ended up with 1 turn out and AFR at 12-12.3 a little rich for idle but throttle response was best here. I then advanced timing from 28-32 deg. Went for rip and WOT AFR was 12.5 now and throttle response was crisp and car pulled hard. spun 1st and 2nd gear with my drag radials. Also my cruise rpm AFR was in 12.2-13.3 range.

Overall, Im very happy with this pro-systems carb and I only had to go up on jetting and tune idle mix slighty. Took about 10-15min to dail it in and car runs great. I def would recommend pro-systems for anyone with a hp motor.

 

Sounds perfect. I guess with this carb you can't really keep the cruise ratios and power ratios separate?

What are you using for wideband? Does it allow you to map against RPM?

 

I have a AEM wideband, i works decent and was cheaper compared to other bands. My data logging is me with a pencil and notebook lol. I have my boost, fuel pressure, and wideband under my cowl for easy viewing. I think there is an optional wire harness and program I could purchase to use real data logging but I haven't got into it too much.

 

I am having tuning issues with my Holley 850. I have been pointed to a pro systems. I was going to ask how you could tell yer AFR, now I see how with the gauge you have.
Does the throttle linkage match a Holley? It looks similar from your pic above. I would need that to mount my existing bracketry.
Great video......

 

You need to be smarter than the moron on the phone telling you to stay smaller with a stick car. That is even wrong for a non-supercharged car. Super chargers at 10 psi is like doubling your cubic inches. So a 350 becomes 700 ci. in the amount of CFM flow through the carb


That is why you see dual 750's on a blower motor. Previously you had a 750 mighty demon. It probably flowed around 800 cfm with annular booster.

You need much more cfm. I would return it and argue that you got dupped by a dumb A$$

Carbs can maintain the most linear A/F ratios when operated within air flow parameters. You don't want the carb restricting flow to the supercharger.

Oh Ya! aren't line locks crowd pleasers?

 

Thats an awesome video. Do you have any details as to what you have done to the rear end to contain all that power. Thanks for your time.

 

Pretty Sweet!!!!!!!!

 

custom built Eaton 12 bolt 4 series case with 3.73 gears.
heat treated 10/17 spiders (30 spline)
custom tuned/polished posi set up
ARP ring gear bolts
Toms Diff steel bearing cap
Billet driveshaft yoke
HD rear cover
Solid pinion sleeve
30 spline Heat treated Toms Inner axles
3.5" Halfshafts
Tom's (31 spline) outer axles with 1/2" wheel studs
Solid rear diff crossmember mounts and traction bar.


Its overkill for my current power level but I eventually want to do a bigger motor and a procharger set up.