Getting started on a 470 stroker, what carb ?

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MOPARMAGA

" The other hard member"
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Hey fabo friends,
I'm looking for help picking the right carb for street & strip, I have a guy from fabo that is a builder & going to have him help with the stuff I can't do.
Here's my build so far;
70 dart swinger, aiming for 2800 pounds
630 casting 73' 400 block
Molnar 3.915 crank
6.70 rods
1.320 SRP pistons.
Compression should be 11.3:1
I have trickflow 240s
I have a couple choices for intake, rpm & trickflow track heat.
Cam is a howards solid flat with 260@.050 intake & 264@.050. .616-.620 lift.
Automatic with 38-4200 stall,
I think thats all the info needed???
I have a #80509 830 classic hp holley now,
I don't have the budget as of now for a fi system so I'm not worrying about that.
What do you guys think?
 
lol

BIG BO.jpg
 
Hey fabo friends,
I'm looking for help picking the right carb for street & strip, I have a guy from fabo that is a builder & going to have him help with the stuff I can't do.
Here's my build so far;
70 dart swinger, aiming for 2800 pounds
630 casting 73' 400 block
Molnar 3.915 crank
6.70 rods
1.320 SRP pistons.
Compression should be 11.3:1
I have trickflow 240s
I have a couple choices for intake, rpm & trickflow track heat.
Cam is a howards solid flat with 260@.050 intake & 264@.050. .616-.620 lift.
Automatic with 38-4200 stall,
I think thats all the info needed???
I have a #80509 830 classic hp holley now,
I don't have the budget as of now for a fi system so I'm not worrying about that.
What do you guys think?


If you had the cash for the carb Rusty posted I’d Beal, for that.

Aside from that, what you have is fine. I’d pin gauge every hole in that thing and write down every hole size.

I’d start with making sure you have only 2 emulsion holes ~.028-.029 and blank off everything else. Depending on what metering blocks that has, it may have 3 or 4 emulsion holes. If 3, block the middle off with a 6/32 brass set screw. You’ll probably need to to for that. If it has 4 you block 2 and 4 from the top.

Next up is to add transition slot restictors. I use a brass 8/32 set screw for that and start with about an .080 hole.

If you don’t have the tools to do it, you can buy them cheap or pay someone to do it.
 
:rofl::rofl::rofl:

528CBA15-684A-41B2-9D54-206C9F8D50DF.jpeg


Seriously speaking, it looks and sounds like a great build and a lot of fun. The 830 should do OK for the street but as you figured, leave some on the table at the track.

I have to ask, what is the balance of the street strip machine?

I think the track heat is the intake to use and as large as you can get the flow rate of the carb. Being limited to a 4150 bolt pattern is the short coming. For max track effort there is nothing better than the tunnel ram and it’s hard to compete against it. It is a lot of work just going through the hood.

Staying tuned!
 
:rofl::rofl::rofl:

View attachment 1715533462

Seriously speaking, it looks and sounds like a great build and a lot of fun. The 830 should do OK for the street but as you figured, leave some on the table at the track.

I have to ask, what is the balance of the street strip machine?

I think the track heat is the intake to use and as large as you can get the flow rate of the carb. Being limited to a 4150 bolt pattern is the short coming. For max track effort there is nothing better than the tunnel ram and it’s hard to compete against it. It is a lot of work just going through the hood.

Staying tuned!


Wish I had that intake. Or the Pro Dominator. Should have kept my PD.
 
:rofl::rofl::rofl:

View attachment 1715533462

Seriously speaking, it looks and sounds like a great build and a lot of fun. The 830 should do OK for the street but as you figured, leave some on the table at the track.

I have to ask, what is the balance of the street strip machine?

I think the track heat is the intake to use and as large as you can get the flow rate of the carb. Being limited to a 4150 bolt pattern is the short coming. For max track effort there is nothing better than the tunnel ram and it’s hard to compete against it. It is a lot of work just going through the hood.

Staying tuned!
Honestly, I won't know the balance till I drive it the 1st time. I may be so enamored I daily drive it. I'll just need to get a night job to pay to drive during the day lol. But I had in mind street 60-40 race, also I have a couple gear swaps I can do for race day.
But again it will depend. Right now I live in communist Seattle WA & the roads are garbage. Hopefully moving a few cities away where commonsense exists
 
If you had the cash for the carb Rusty posted I’d Beal, for that.

Aside from that, what you have is fine. I’d pin gauge every hole in that thing and write down every hole size.

I’d start with making sure you have only 2 emulsion holes ~.028-.029 and blank off everything else. Depending on what metering blocks that has, it may have 3 or 4 emulsion holes. If 3, block the middle off with a 6/32 brass set screw. You’ll probably need to to for that. If it has 4 you block 2 and 4 from the top.

Next up is to add transition slot restictors. I use a brass 8/32 set screw for that and start with about an .080 hole.

If you don’t have the tools to do it, you can buy them cheap or pay someone to do it.
Yeah when I run numbers on calculators I come up with my carb up to 925 cfm.
I am going to put a 850 base plate on, I think there's a little massaging. Thank you for your reply
 
:rofl::rofl::rofl:

View attachment 1715533462

Seriously speaking, it looks and sounds like a great build and a lot of fun. The 830 should do OK for the street but as you figured, leave some on the table at the track.

I have to ask, what is the balance of the street strip machine?

I think the track heat is the intake to use and as large as you can get the flow rate of the carb. Being limited to a 4150 bolt pattern is the short coming. For max track effort there is nothing better than the tunnel ram and it’s hard to compete against it. It is a lot of work just going through the hood.

Staying tuned!
Oh yeah also when I'm confident in my tig welding abilities I plan on making myself a tunnel ram out of 1/8th inch or 3/16 aluminium plate, probably do a 12 inch runner cross ram deal, or a single 4500 flanged 12 inch straight up deal. (ahh the life of a big dreamer....but I usually can make them become reality). Thanks for your reply
 
The 80509 carb will work just fine for what you're building. Save your money for something that matters.
 
I had a Pro systems 950 carb on my BBC , was the biggest pile of crap i ever owned. It went with the car when i sold it. Plus Patrick has no customer service skills. It took me a while to sort out all his mistakes on that carb.
 
The 80509 carb will work just fine for what you're building. Save your money for something that matters.
Thanks andy, the carb is good up to 6200 by holleys recommendations, I will be replacing & massaging a 1.75 base plate on, holley guy said throttle response would pick up. if I was looking to get closer to my max rpm of my cam & heads ill need to step up to a 1050 dominator & your right, there's better stuff to buy & there's always time to upgrade
(Well that depends on no lunatics in office)
 
I had a Pro systems 950 carb on my BBC , was the biggest pile of crap i ever owned. It went with the car when i sold it. Plus Patrick has no customer service skills. It took me a while to sort out all his mistakes on that carb.
That's basically a 750 with an 850 baseplate if I'm not mistaken. Way overpriced, thanks for letting me know that.
I think I'm just going to put a billet 850 baseplate on my 830hp.
 
What's wrong with the baseplate on the one you've got?
Nothing's wrong with it, just that it's nearly a the same venturi as throttle bore. It basically turns it into an 850
 
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