Adapting a SBC Intake to a SBM

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Because I need a mechanical fuel injection manifold, which are very uncommon for small block Mopars and if I do happen to find one it will likely be very expensive, Hilborn for SBC is very common.
 
racerdude5 said:
Because I need a mechanical fuel injection manifold, which are very uncommon for small block Mopars and if I do happen to find one it will likely be very expensive, Hilborn for SBC is very common.
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I was contemplating something the same thing. I finally bought a pair of 4 cyl big bike EFI setups, but haven't done anything with them yet.

I've also tried to find out--and have not--what else might have similar port spacing, EXAMPLE

If the B/RB stuff was "close" or could be port matched, you could buy a B/RB setup and adapt to a DIY side flange/ valley plate. That would not be too hard if the ports were similar. If the pair-to pair spacing is off, you could cut them apart

There are others built this way, I think? some of the Buick/ Ponchos/ Olds, don't remember

Like these

Mopar B/ RB

s-l1600.jpg


394 Olds

s-l1000.jpg


Poncho

s-l300.jpg


s-l1000.jpg
 
I read online that the small block chevy and small block mopar port spacing are only .06 off, I could be mistaken
 
here a pic that might help>>> SBC engine blueprint....

Treblig
 

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I've looked at the same, and IIRC RB port size and spacing is close, but the ports for RB are definitely larger and again if I remember correctly they would still need to be split in the middle and shortened.

Buy some intake manifold gaskets for various styles and see what is closest, but all will require some cutting and welding.
 
..and you don't think this adaptation is going to be very expensive? you may be trading one devil for another.. just thinking out loud..
racerdude5 said:
Because I need a mechanical fuel injection manifold, which are very uncommon for small block Mopars and if I do happen to find one it will likely be very expensive, Hilborn for SBC is very common.
Click to expand...
 
If you must have a Hilborn set up do some homework. They are a big piece of garbage on the street. They either idle or they are wide open. I would hate to see you modify a Chevy piece and then decide it is garbage. You can use the stacks and the butterflies to control the air but you need a complete port injection set up to make the rest work.
 
Kinsler does offer a stack style injection system, but for w7/w9 heads or brodix ascs heads. Not sure if there's a difference at the intake bolt pattern for the ascs? I'm simply not familiar and didn't dig much deeper at the time since it's mostly fantasy for me.
 
Bung the inboard of each bore for a injector and fuel rails. run a MAP to the center distribution block so it can average all the bores manifold pressure via the old fuel hoses. BMW M3 uses individual valved runners in this manner for big power.
e30-m3-groupa.07.JPG
 
toolmanmike said:
If you must have a Hilborn set up do some homework. They are a big piece of garbage on the street. They either idle or they are wide open. I would hate to see you modify a Chevy piece and then decide it is garbage. You can use the stacks and the butterflies to control the air but you need a complete port injection set up to make the rest work.
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Vote best post.
 
toolmanmike said:
If you must have a Hilborn set up do some homework. They are a big piece of garbage on the street. They either idle or they are wide open. I would hate to see you modify a Chevy piece and then decide it is garbage. You can use the stacks and the butterflies to control the air but you need a complete port injection set up to make the rest work.
Click to expand...

I believe this may be part of his other thread with his 318 sprint car engine build. Hilborn setups are very common on them and run great at the 7k+ rpm they run. But I could be mistaken.
 
Yep, this is for the sprint car. I am aware it would be a disaster on the street. My idea was, as you can see how close the ports are to matching, machine the port surface so it will sit in the valley of the Mopar like it should (assuming the angle of the intake port surface is different), then grind off the bolt holes and weld on a flat plate and re-drill it for the Mopar bolt pattern or something like that. Then finish up with port matching. The only other idea I've had was to start with a tunnel ram... Or I could just try making an intake out of aluminum tubing... Hmm.. Thoughts?
 
You'll buy a decent tig and make your own for cheaper than buying what you need to do this, but I'm curious as to why mechanical injection? You can go EFI and make more power and do so far easier.

Governing body limitation?
 
jos51700 said:
You'll buy a decent tig and make your own for cheaper than buying what you need to do this, but I'm curious as to why mechanical injection? You can go EFI and make more power and do so far easier.

Governing body limitation?
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Yes, sprint cars have no charging system and no battery either. They use a magneto. Your not allowed to use any digitally controlled engine functions.
 
racerdude5 said:
Yes, sprint cars have no charging system and no battery either. They use a magneto. Your not allowed to use any digitally controlled engine functions.
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which is weird because I could have sworn I saw a car with an MSD ignition box... :/
 
racerdude5 said:
The only other idea I've had was to start with a tunnel ram... Or I could just try making an intake out of aluminum tubing... Hmm.. Thoughts?
Click to expand...

I have thought about that as well. There recently was a TR on here I thought would be a good candidate. I forget, I thought Weiand or Offy would work, Edelbrock would not because of the way the "valley" cover is done. On the Ed, there's a big cavity

Here's an Ed that sold on here.

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Weiand. This might be better

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My fab skills are not that "great," but I've thought about building or buying intake manifold flanges, and tacking up a valley pan and just build one. It would be steel, tho, not aluminum.
 
AFR Polyplastic? Edelbrock dual quad wouldn't work cause it has plenums. Yeah, that tunnel ram would be perfect, or so I'd like to think.
 
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