SBC tunnel ram carb change , READ... MORE CFM

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Tuner
Guru
Guru
Posts: 1890
Joined: Sun Apr 01, 2007 5:26 am

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by Tuner » Sun Sep 10, 2017 5:43 pm

A pair of 1050 4500s or don't bother. :wink:

joespanova
Expert
Expert
Posts: 702
Joined: Sat Dec 01, 2007 5:15 pm
Location: McDonough Ga.

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by joespanova » Sun Sep 10, 2017 7:04 pm

Tuner wrote:A pair of 1050 4500s or don't bother. :wink:
2 Dominators on a 377? I'd have to see that to believe it ( that it would pick the car up )...............lol
BTW , who wants to predict what a carb change might do ? :mrgreen:
modified wanna be

statsystems
Guru
Guru
Posts: 1112
Joined: Sun Apr 03, 2016 1:17 am

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by statsystems » Sun Sep 10, 2017 7:32 pm

joespanova wrote:
Tuner wrote:A pair of 1050 4500s or don't bother. :wink:
2 Dominators on a 377? I'd have to see that to believe it ( that it would pick the car up )...............lol
BTW , who wants to predict what a carb change might do ? :mrgreen:

It's done all the time. Don't get caught up in CFM numbers. No sense using 660's on anything. 750's are plenty small. I agree with tuner. 2 1050's.

I have a matched pair for sale but I'll tell you they are 3 circuit. I'd make you a smoking deal.

Tuner
Guru
Guru
Posts: 1890
Joined: Sun Apr 01, 2007 5:26 am

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by Tuner » Sun Sep 10, 2017 7:47 pm

statsystems wrote:
joespanova wrote:
Tuner wrote:A pair of 1050 4500s or don't bother. :wink:
2 Dominators on a 377? I'd have to see that to believe it ( that it would pick the car up )...............lol
BTW , who wants to predict what a carb change might do ? :mrgreen:

It's done all the time. Don't get caught up in CFM numbers. No sense using 660's on anything. 750's are plenty small. I agree with tuner. 2 1050's.

I have a matched pair for sale but I'll tell you they are 3 circuit. I'd make you a smoking deal.
Bob Glidden's ProStock Plymouth Arrow engine was a 340 with a pair of R-6464 1050s. The carb setup and 2 circuit jetting instructions are in the Mopar engine book.

joespanova
Expert
Expert
Posts: 702
Joined: Sat Dec 01, 2007 5:15 pm
Location: McDonough Ga.

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by joespanova » Sun Sep 10, 2017 8:34 pm

It'd be nice if I had a dyno.............I could learn a hell of a lot easier.
modified wanna be

F-BIRD'88
Guru
Guru
Posts: 5658
Joined: Tue Mar 27, 2007 6:56 pm
Location: Ontario, Canada

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by F-BIRD'88 » Sun Sep 10, 2017 9:26 pm

If bigger carbs gained 50 hp and that made the car a little faster, will that make you more money or make the girls like you better,?

bigjoe1
Show Guest
Show Guest
Posts: 6162
Joined: Thu Aug 24, 2006 8:16 pm
Location: santa ana calif-92703
Contact:

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by bigjoe1 » Sun Sep 10, 2017 9:44 pm

I ran two 1050 Dominators on a 377 way back in 1990- It made 710 HP at 8000-- We turned it 8800-9000 in the car- It ran 970 at 139 with a 2 speed powerglide and 5.57 gears




JOE SHERMAN RACING

randy331
Guru
Guru
Posts: 2548
Joined: Mon Dec 04, 2006 7:30 pm
Location: N.W. MO.

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by randy331 » Sun Sep 10, 2017 10:02 pm

joespanova wrote:It'd be nice if I had a dyno.............I could learn a hell of a lot easier.
Or get lots of info that conflicts with commonly accepted ideas.

Randy

tjs44
Pro
Pro
Posts: 399
Joined: Thu Jul 07, 2005 2:30 pm
Location: long beach.ca

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by tjs44 » Sun Sep 10, 2017 10:09 pm

Go back to post 2.Tom

Tuner
Guru
Guru
Posts: 1890
Joined: Sun Apr 01, 2007 5:26 am

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by Tuner » Sun Sep 10, 2017 10:40 pm

Here's your sign. :D
bigjoe1 wrote:I ran two 1050 Dominators on a 377 way back in 1990- It made 710 HP at 8000-- We turned it 8800-9000 in the car- It ran 970 at 139 with a 2 speed powerglide and 5.57 gears

JOE SHERMAN RACING
statsystems wrote:
joespanova wrote:
Tuner wrote:A pair of 1050 4500s or don't bother. :wink:
2 Dominators on a 377? I'd have to see that to believe it ( that it would pick the car up )...............lol
BTW , who wants to predict what a carb change might do ? :mrgreen:
It's done all the time. Don't get caught up in CFM numbers. No sense using 660's on anything. 750's are plenty small. I agree with tuner. 2 1050's.

I have a matched pair for sale but I'll tell you they are 3 circuit. I'd make you a smoking deal.
:mrgreen:

joespanova
Expert
Expert
Posts: 702
Joined: Sat Dec 01, 2007 5:15 pm
Location: McDonough Ga.

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by joespanova » Mon Sep 11, 2017 7:10 am

F-BIRD'88 wrote:If bigger carbs gained 50 hp and that made the car a little faster, will that make you more money or make the girls like you better,?
Its funny you mention that...............that's exactly WHY I'm doing this , a-hole.
Anyway.......it all started from needing new boosters in my 660's since some of them were very loose. I called a few shops and no one wants to mess with 660's. In fact the first shop I called was Patrick's shop ( Pro Systems ). My request was , can you install new boosters and while you're here is there anything I/we can do ( like the old 850 base plate mod ) that's worth the time and effort. No interest.
So I left a message , he called me back , we talked and he wants to sell me a couple 750s he practically guarantee's will make the car quicker.
I'm not easily convinced.
See , its like this................I run some nostalgia stuff , the 9.50 / 6.0 stuff. If its possible the 750's get me to the next index ( 9.25 ) , why not try it. Actually I could care less anymore.....but it was interesting to hear opinions anyway.
Certainly carb shops want to sell carbs...............but then , that's why I'm here now...........for educated " unbiased" opinions.
modified wanna be

In-Tech
Guru
Guru
Posts: 1510
Joined: Wed Apr 21, 2010 4:35 am

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by In-Tech » Mon Sep 11, 2017 8:05 am

Hi Joe,
Typically with tunnel rams the fuel curve gets all facked up, mainly going rich on the top end. A pair of bigger carbs is never a bad idea but if you want to deal with what you have, get to tuning. Since you have a loose booster maybe some downlegs are in order rather than the crappy one's that come on the 6224's. I think I have some 6109's laying around, I'll have a look later today.

Fun little tunnel ram story, a bud at a boat shop with a pickle hydro has me work on his carbs, pair of dp 750's on a 454. He was tickled that he was able to cruise the entire 5mph zone at havasu without reving it up to clean it out multiple times from loading up at idle :roll: Wet exhaust and I wasn't going to ride in the boat a friendly bet emerged with the other guys in the shop. A paid lunch bet that we could have the engine pulled, dyno'd and back in the boat by noon equated to a 75hp increase and of course we won the bet too. =D> We're at the river for the maiden voyage and he came back with a grin ear to ear saying it picked up 15 mph and never quit pulling(everyone here that knows a hydro/tunnel knows the faster it goes, the less boat in the water and the faster it goes as long as rpm can increase).
Anyhoosit he says I might need to readjust the carbs as it's not idling so good. I hit the recall on the tach and it's 8800rpm [-X Hey dumbass, you floated the valves and bent some is why it's not idling...smile gone :mrgreen:
Heat is energy, energy is horsepower...but you gotta control the heat.
-Carl

NormS
Member
Member
Posts: 121
Joined: Sun Dec 13, 2015 10:21 am
Location: Vassar,Michigan
Contact:

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by NormS » Mon Sep 11, 2017 8:27 am

Iv'e built a lot of 660's for dual quad set ups. The 1 1/4" primary venturis give the straight leg boosters a signal curve that makes the mixture go progressively richer as the airflow goes up. The same straight leg booster in the 1 5/16" secondary venturi has a considerably better signal curve for maintaining a good A/F ratio. I've modified many pairs of these carbs so that all 4 venturis are the same size, anywhere from 1.320" to 1.450". Yes, that does increase air flow, but more importantly, it gives a much more manageable booster signal curve, which improves the full throttle fuel metering dramatically. Power gains for you will come from better fuel metering and fuel conditioning, more than from the CFM increases.

Even though 660's are limited on what you can do with the throttle linkage,because they are center squirter carbs, that doesn't mean they are outdated or junk. They can be made to work very well, as is the case with most performance Holley carbs made in the last 50-60 years. Norm/CFS
Competition Fuel Systems Vassar, MI.

joespanova
Expert
Expert
Posts: 702
Joined: Sat Dec 01, 2007 5:15 pm
Location: McDonough Ga.

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by joespanova » Mon Sep 11, 2017 8:42 am

Thanks for info and stories guys.
modified wanna be

tenxal
Pro
Pro
Posts: 366
Joined: Sun Nov 17, 2013 8:48 pm

Re: SBC tunnel ram carb change , READ... MORE CFM

Post by tenxal » Mon Sep 11, 2017 8:59 am

joespanova wrote:It'd be nice if I had a dyno.............I could learn a hell of a lot easier.
Maybe. Maybe not.

One of my QJets shows 8 hp more on the dyno but is slower on the track. :wink:

Post Reply