Projects Building My 34 B'Ville Coupe With a Potvin

Sure would like to find a Hilbourn 2 port for a 6/71 that would top it off. So here is the next project. Because i want to run EFI (yes Not period correct) I want to hide the injectors under the runners. There is no room so I took a Hot Heads dual carb manifold and gently removed the runner sections from the plenum. This manifold has the runners standing more vertical thereby allowing more room under the plenum. When I'm done adding the tubing to the tops of the runners I'll add a top and bottom and ends to make it look like the Potvin unit pictured.

 

Now it’s starting to take shape. I had a good friend Dan Fantini fish mouth the runners.

 

That is neat.....

 

Looking forward to seeing the new top in it's finished glory!

 

That look great! One of the coolest pieces of Tech on the board right now.

 

Thanks TMAN

 

Do you know how your friend Dan Fantini fish mouthed the runners? Maybe horizontal mill with over arm support?

Beautiful Work!

 

Bigger pic

 

Sure He used a boring head on his vertical mill with the head rotated about 40 degrees. The problem he ran into was when you lean the tool over it cuts an ellipse so he had to reset the bore diameter as he went deeper

 

So a little back asswards but this might as will be a build thread. After starting on the engine (previous posts), I now have a little time to start on the chassis build. First off. Thank You guys for any and all feedback i have and will receive during this build. It's not going to be fast (the build) but hopefully i can stay at it steady.
As I couldn't borrow a chassis table i had to build a cheap unit that will work for this build then give/sell/ or cut it up.

 

I just noticed you build side plate adapters for the 301 quick change. Do you still make them? I have a 11 bolt 301 halibrand I'd like to use.

 

Check his threads, he has a whole thread on them!

 

Yes, I saw that but they were posts from 2016. I want to know if he still makes them.

 

Im glad to see you’re going to make this a build thread. The level of thought going into your decisions is inspirational. Keep it up, and thanks for sharing.


Sent from my iPhone using H.A.M.B.

 

Thank

 

I sure do. Start a conversation and I can help you out.

 

Sorry for Jumping around. I got the frame down off the wall and started the dis-assembly. How many rivets in a 34 frame? A FREAKIN MILLION OF EM. well not quite but i hate taking old frames apart. Next will be the repairs and then the mods. After 2 days of swinging body hammers (a 3 LB. and a 2 LB.) i have the rails in pretty good shape along with the inner frame/xmember. I started to repair by cutting out the rust at the rear kickup then realized I didn't have any material so onto other stuff. QUESTION. Is there a preference for large images or the thumbnails??



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larger images please

 

So one of the mods I want to do is stretch the frame 3 inches to try and make a little more room for the Potvin. I decided to cut the frame just ahead of the steering box mount. To kill 2 birds at once I'm using replacement frame horns. I had to massage the new horns as the rails and the horns were different depths where i wanted to join them. Besides the vertical cut i also had to make a horizontal cut in the new horn to make them match up. then it's a case of clamping them all up and carefully welding them up. Onto the other rail except it has a problem. In the last pic you can see that the un modified rail is about an inch low in the crossmember area. Luckily the rail just needs to be corrected back where it starts to kick up and will only needs to be corrected in one spot. Once the rails are patched straightened and ready to go back together I'll put the body on and make some decisions on further mods.

 

Okey Dokey TMAN

Ted

 

I like your thinking on the intake manifold re: hiding the EFI injectors. I hid mine under the SBC Potvin intake and had to put everything in the valley of the block. Finger's crossed they never leak! Are you planning on running fuel through the blower? Have you figured out your wheelbase yet? What are you going to do for radiator, alternator, and water pump or did I miss those details?

Great build by the way!

 

Large please

 

I'd love to see a inspired image of the desired look of this street monster...

 

I don’t think I’d worry too much about an injector leak. There are production cars with the injectors under the intake. The plan for the wheelbase is 115 but may change once I get it together enough to fit up a nose piece. I’m really fussy about how the proportions look. I don’t want it looking like Pinocchio.
The rad will need to be in the trunk with 2 electric pumps. One pushing water each way.
For the charging my first plan is to mount it above the blower with a pulley running off the end of the blower. The pulley part is already built and I’ll take a pic of it but it may not make it to the final product. It adds 3.5 inches to the length and I don’t know if it will fit. The alternator will need pretty good output as there are more than a few motors to run.
As for putting fuel through the blower, they were never designed for that. They were designed to only move air. Yes there are many special instances where people have put fuel through them and it works fine but that is because of the special usage.
Here’s something I,ve thought about, the blower was never designed to be mounted by the end plate. What affect will it have on the operation? Will the case flex, will the rotors clash.

Ted

 

My concern is with an O-ring leak at the fuel rail, under the intake. But that's OT.

Funny, your wheelbase is exactly the same as mine, 115-inches. Body is '29 roadster. Radiator will be in the rear as well, though I didn't think about having a pump on both ends. Thought about driving the alternator off the blower, but had the same concerns as you. Ended up driving it off the driveshaft, mounted on the quickchange. Plans are to use a deep cycle AGM and a capacitor bank to help with the load.

I wasn't planning on running fuel through the blower, but a few folks with more experience than I recommended it due to the heat that will be generated by the rotors. Food for thought.

I thought the same regarding the blower being mounted by the end plate but have never heard of any failures due to the design. I know of a handful of Potvin setups being used at Bonneville/El Mirage and there's one in a T-bucket that's been on the road for years. I still put a 2x4 under the blower when the engine is on the stand! LOL

 

I thought about running the alt off the driveshaft but I want the no/low speed charging. I had a car with that setup years ago and in traffic the battery voltage kept dropping off. Now that was 30 years ago and the tech has changed.

 

Somebody made at least one change gear setup for that blower drive because I saw it at Bonneville many moons ago.

 

Yup, there have been a few. Chico @ Mooneyes is running one in his Modified Roadster.