Hi guys, planning a roadster build - wondering how much room you loose with a BB/409 vs a small block or flathead? (6'5 34" inseam) Thanks
All those engines require the same minor fitment to the firewall, i.e. a flat firewall. So run what you like.
I'm similar size as you. A friend has a 409 32 roadster that I fit in. Foot room next to a tunnel is very tight with big feet, so be careful with the shape of it. A thin seat back will do a lot for your comfort, and a low seat base will help you fit in instead of on the car. Guys our size need to spend much more effort on mockup layouts to make sure we can enjoy these small cars after all the effort to build one.
I am 5'11 and I have plenty of room in my 32 with a mostly stock firewall and SBC . These cars are much larger than a model A - and with seat adjustment you should be fine. The height of the windshield will be your issue. Also - You do not need a flat firewall - mine just has a notched center for the distributor - and I see 32s all the time with this setup. Check out This build (Hotrodpro). He has a bbc and a stock firewall that he modified to fit. With you're height - you may want to consider a body that is lengthened. I've seen 2" added in the doors on roadster bodies. http://www.jalopyjournal.com/forum/threads/a-new-32-project-of-my-own.973954/page-18#post-11436950
I was going to suggest a thin seatback, but someone has already covered that. I am only 5'07", but with the total 3 1/2" setback of the firewall, I am figuring how to have the seatbacks on the glide seat thinned out. My glide looks kinda hokie. The seats that seem to work best are the original design that follow the curve of the body. Many of them are custom made, and at your height, you will need to consider the chop of the windshield. What agshelby said is true. Small distributor is also necessary. Wish I could do the roadster over; I would have plenty of footroom.
I don't have a clue how you could loose room. In fact the question makes no sense at all. You could however lose room.
flatheads and sbc's are no big deal... no mods needed on the firewall. I think the 409/bbc will cause some firewall issues but if planned correctly you may not lose much foot room
A big block (396/427/454) is 2" longer than a small block so if the location of the front of the motor is determined by radiator/fan considerations the back of the motor/bellhousing etc will be that much closer to you. Roo
This is how Brizio recessed the firewall on this 3 window. Notice it gives the appearance of being stock. They performed the same recess on the 3 window that John Mumford had built, and it features a 348/409 mill Doing it this way you really don't loose any of the aesthetics of the original firewall, and leg room is not compromised.
There are a few more things involved here that would have to be addressed. Fenders/no fenders. With fenders hood length and radiator placement are somewhat critical while a lot of fenderless rods have frames that are stretched a tad for engine room without modifying the firewall to an extent. I'd agree with the trial fit, plan trial fit some more concept and with keeping the trans tunnel to a minimum. I've been in several rods with huge trans tunnels that had little or no foot room where the builder could have done much better on that part. It's one thing to have to swap from your walk around the show comfort shoes to your thin "driving shoes" to be able to drive more comfortably but a whole different ball game when the car gets left in the garage on anything but short trips because it is uncomfortable to drive for any distance.
I am 6' 7" with a 38" inseam. I have a steel deuce roadster with a '56 365 cadillac. I didn't have to trim the firewall for clearance at all. I simply had to trim the lower part of the firewall to clear the adapter to the chev bell housing. I have a smaller than stock fan, 17" or so, and use a stock model A coupe seat with 1" square tube under the stock tracks. The seat was custom made with deep contours and the back of the seat is under the tack strip area. I fit in it fine and my windscreen is chopped 3".
The small block is a natural fit in a '32 and my original roadster with a 283 and '39 transmission fits with only a slight notch to the firewall above the bell housing. Everything else clears, heads, distributor, ect. A friend has a 396 in his '32 5w and used a flat firewall to clear the heads. There is no need to modify the stock firewall with a small block.
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