427 SBF

89 Fox 427 said:
Yes, thinking about it
Click to expand...
I wouldn't waste the money on it if you can't put the "proper" intake on the engine, just not worth it at this time. Too bad you can't do EFI. A throttle body is pretty thin (height-wise) and would buy you a lot of hood clearance, plus no issue with it being close to the hood like a carb. I understand the price can be an issue. I use the Holley Terminator ECU on "budget" stuff. Pretty good system, far less money than the HP or Dominator ECU's I use on my race cars. Doesn't have the internal datalogging like my stuff, but can still do it via a dash or laptop.

But........ The fuel pump, injectors, regulator and throttle body do add-up...... If building a combo from scratch and you have nothing, then EFI really isn't that bad. But if you have a running setup and no one to buy your old stuff then yeah, it's a big hit.
 
89 Fox 427 said:
The original ORIGINAL plan was 450hp.

Buying the dart block the goal was 650 and a 10.5.
Click to expand...
What does it weigh? The wifeys race car is 3500 with me in it, goes 10.5 @ 128. It is a 406 SBC, compression to be determined........ I thought it was sub 11:1, it can't be after seeing the pistons in it. Anyway, we ran this engine for 6+ years in her car, bought it used from a street/strip deal like yours. He did tell me at the track he ran it on purple. Anyway, mild cam, I have the specs, idles VERY smoothly at 1000 rpm in gear. I have idled at 800 but I like it better at 1000.

According to the Wallace Racing Calculator her engine makes about 600hp. This thing is really mild.

BTW: We have stock out of the box AFR210's on her engine and an Edelbrock EFI intake, I think it is based off the Vic Jr, low rise single plane.
 
Last edited:
Mike Beck said:
What doe sit weigh? The wifeys race car is 3500 with me in it, goes 10.5 @ 128. It is a 406 SBC, compression to be determined........ I thought it was sub 11:1, it can't be after seeing the pistons in it. Anyway, we ran this engine for 6+ years in her car, bought it used from a street/strip deal like yours. He did tell me at the track he ran it on purple. Anyway, mild cam, I have the specs, idles VERY smoothly at 1000 rpm in gear. I have idled at 800 but I like it better at 1000.

According to the Wallace Racing Calculator her engine makes about 600hp. This thing is really mild.
Click to expand...

I have zero clue about the weight. Lots of shit removed, no heat/ac, no sound deadening, no rear seats, the typical suspension upgrades and lightweight kmember, aluminum rear bumper I made for fun.. but the cage, bigger engine, huge trans.. who knows!

And I sure don't want a smooth idle. If it sounds smooth I want a refund! I get shit for it, but I love the sound of those thumpr cams or rattler cams.

I put numbers in that calculator on Wallace. To run 10.5 @ 130 at 3300lbs shows about 500 to the wheels
 
Briansshop said:
It doesn't take much to get weight out of a Foxbody. Mine was at 2600lbs w/out driver easy.
Click to expand...

I'm eager to scale it. Captain lightweight, I mean Patriot Racer called me fat. I did have a 22 gallon fuel cell made, better keep that empty for track days
 
89 Fox 427 said:
I'm eager to scale it. Captain lightweight, I mean Patriot Racer called me fat. I did have a 22 gallon fuel cell made, better keep that empty for track days
Click to expand...
Once running, just find a place with a truck scale. You can ask them if you can pull halfway on and get a weight. Then pull all the way on and get full weight. That's what I did before I bought race car scales.
 
Patriot Racer said:
Once running, just find a place with a truck scale. You can ask them if you can pull halfway on and get a weight. Then pull all the way on and get full weight. That's what I did before I bought race car scales.
Click to expand...
Truck stop scales have different platforms for the truck and the trailer , park the front half of the car on one platform and the rear on another
 
Going to notch the divider of this absolutely horrible never going to work dual plane this weekend if I get a minute. I'll probably knock it down 3/8 to 1/2 inch or so
 
89 Fox 427 said:
I'm eager to scale it. Captain lightweight, I mean Patriot Racer called me fat. I did have a 22 gallon fuel cell made, better keep that empty for track days
Click to expand...
Every track I have ever raced at has scales.

I think the Wallace calculator is flywheel power. I went 156mph @ 3400 pounds on juice years ago. I believe their calculations. It says 1069hp. Pretty sure my engine makes 725ish. I had a .063N and .030's in the DP, so I was running about 400ish of juice through it back when I did my 8.90 Index stuff. I figured it took about a 1000hp at that weight to do that. I was always deep-staged so it was actually in the 8,.8x range.
 
89 Fox 427 said:
Going to notch the divider of this absolutely horrible never going to work dual plane this weekend if I get a minute. I'll probably knock it down 3/8 to 1/2 inch or so
Click to expand...

What are you going to do to the edge?
I just looked at some big block Chevy pictures.
It looks like Edelbrock just mills it and leaves it flat on the Performer RPM, which is notched like you're talking about.
The Air-Gap looks like it's taken all the way to the floor.

I have an Air-Gap on a shelf somewhere.
If I remember I'll look at it after I'm done with yard work.
 
Steve439 said:
What are you going to do to the edge?
I just looked at some big block Chevy pictures.
It looks like Edelbrock just mills it and leaves it flat on the Performer RPM, which is notched like you're talking about.
The Air-Gap looks like it's taken all the way to the floor.

I have an Air-Gap on a shelf somewhere.
If I remember I'll look at it after I'm done with yard work.
Click to expand...

Old air gaps (like mine) are not notched. The pics on Amazon looks like it's notched 3/8" or so. The pics on summit there's no notch. Edelbrock website, no notch.

Who the fuck knows
 
89 Fox 427 said:
Old air gaps (like mine) are not notched. The pics on Amazon looks like it's notched 3/8" or so. The pics on summit there's no notch. Edelbrock website, no notch.

Who the fuck knows
Click to expand...

They're all over the place!

BBC - both RPM and Gap are notched, but at different depths.
SBC - RPM not notched, Gap notched.
SBF - I can't even tell

I just realized I don't have a carb on my BBC with the RPM.
The notch is about 9/16" deep, the sides are flat, and the bottom is radiused a bit.
 
Steve439 said:
They're all over the place!

BBC - both RPM and Gap are notched, but at different depths.
SBC - RPM not notched, Gap notched.
SBF - I can't even tell

I just realized I don't have a carb on my BBC with the RPM.
The notch is about 9/16" deep, the sides are flat, and the bottom is radiused a bit.
Click to expand...

I'm going to go 1/2", radius front and rear, and turn what's left of the divider into a rounded point instead of flat
 
The air gap carb plate is 3 degrees downward. Meaning from pad height (5.75") out to the end of a 14"air cleaner (7") a Victor junior would give me 0.37" less hood clearance. So I'm pretty sure that's out. Mark also said the vic jr wouldn't be worth it for this application anyway. Vic sr or stick with what I got

20250606_114814.jpg
 
Milling down 1/2" from the divider barely gets me into the front runners (cylinders 1 and 6) I don't know if that's good or bad 🤷‍♂

20250606_120213.jpg
 
The rear runners (cylinder 4 and 7) is thicker, presumably because of the angled carb pad

20250606_120251.jpg
 
Talking out loud, it just struck me.. the design of this will pull from a different plane with each stroke. Alternating one plane to the other with the firing order 1-3-7-2-6-5-4-8

Which of course is the proper firing order for you LS guys (we don't even talk about Mopar)
 
Last edited:
I just looked at my BBC Air-Gap.

The notch is 3/8" deep and it's more radiused than my RPM and the sides are radiused too.
The radius is pretty much a perfect half circle.
As I said above, the RPM is 9/16" deep

The Air-Gap is more than ten years newer than the RPM so they may have updated their ideas.

I think you have your answer.
 
You must log in or register to reply here.
Back
Top