rb tunnel ram on a b motor

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mygasser

mygasser

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hi all,
i'm struggling to find a tunnel ram for my 383 for reasonable money here in the uk. i've got a lead on one for a 440 so if i get it the plan is to narrow the base (cut a section out of the middle, lengthways), weld it back together then adapt the top back on. the ally welding isn't an issue, but any other problems i may not have thought of?
cheers, neil.
 
I think your going to have some difficulty with narrowing 2 inches out of that without radically altering the runner shape/transition. That’s not going to matter as much with LPG, but you’ll still want to do it in a way to equalize the runner shape, length, and angle as much as possible. What brand of manifold is it? I don’t think it would be impossible to do, but it would definitely be challenging.
 
just make one.

Hot Rods - Let's see your homemade speed equipment

LPG is already a gas so atomization is not an issue so your runners can look like crap as they will not pool fuel like a carbs. Almost a dry intake and that can look like a maze. Get 8 2" 45's and shape the ends to port size. Get some intake flanges made or cut your own. The bathtub intake gasket already seals the valley. Weld up the 45's to the intake flange and collect them all into a plenum with your 2 mixers. with a little math you can determine the optimum intake runner volume and length. 383 is a great motor to do this on as well as a 351C as they are both dry (coolant free) intakes. I dont see how your going to section out a RB intake and get it all back together with no leakage unless you got a mill and a vertical band saw. Good luck.
 
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Here you go. Small block chevy tunnel ram, two adapter plates. Thats about it. This was done quite often in the 70s. Do some measuring and you will find them close. And if you cant find a small block chevy manifold, well,,,,,,,,
 
I like that, I can't recall much but I think I have heard of that being done before. It sounds like a wonderful plan for a vintage Edelbrock TRY1 tunnel ram. Short yet narrow tapered runners, large plenums. I imagine a B 383 with decent heads on LPG could make decent use of one of those.
 
Just get what is made to fit.
 
As someone who is currently fabricating a blower manifold for my B engine, I feel your pain. Albeit I’m on this side of the pond where they are (somewhat) plentiful. The amount of time and energy has not yet exceeded the $1650 they go for. I ordered an exhaust manifold for my aaf 5cyl and belly pan from the UK for my 93 Transporter. Shipping was surprisingly friendly on my wallet. But, this was the first thing I thought of when Someone suggested fab your own tunnel ram
BF115EC6-C506-4815-8921-F079FA6C0AC2.jpeg
 
The High And Mighty Plymouth. This is the car that the Ram Chargers ran out of the back door of the chrysler factory and put all the theory about ram/sonic tuning into practice.
 
i bought the 440 tunnel ram, got the guy down to £130 sterling. it's only metal so i'll make it work. i may take a section out of the runners each side then drop the centre back down in the middle to narrow it for my 383. if that doesn't look doable i'll just remove a section lengthways from the base then adapt the top back on. we'll see, my time's free so.......
cheers, neil.
 
If you don’t mind me asking, what brand of tunnel ram did you find? Just curious because you mentioned it having a base.
 
You’ll definitely be narrowing the base, an RB intake is two inches wider than a B intake. That is the best cast tunnel ram made for a Mopar big block. I suggest PM’ing AndyF, he would probably know the most practical way of accomplishing your goal. As a cautionary note, maintaining the as cast port transition to the port window in those intakes is critical to maintaining the performance.
 
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TheGrateRonzini said:
As someone who is currently fabricating a blower manifold for my B engine, I feel your pain. Albeit I’m on this side of the pond where they are (somewhat) plentiful. The amount of time and energy has not yet exceeded the $1650 they go for. I ordered an exhaust manifold for my aaf 5cyl and belly pan from the UK for my 93 Transporter. Shipping was surprisingly friendly on my wallet. But, this was the first thing I thought of when Someone suggested fab your own tunnel ramView attachment 1715306354
Click to expand...
That looks like a long ram. LOL
 
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