Does the firewall need to be recessed to fit a sbc/tremec? I have an option to buy a OEM firewall for $500. But if I have to recess I feel like a aftermarket that has already been recessed is a better buy. My 33 will be channeled.
My 33 has a stock firewall with a small recess to clear the distributor. Very tight, but without the distributor recess it wouldn't have fit.
If you use a pre-1969 water pump & associated pulleys, along with a small diameter distributor (like the pre-electronic ignition version), no firewall mod will be needed. But, now you’re faced with mounting the alternator/generator, which may not be a concern for you (no hood, no fenders, no problem).
The small Mallory will just barely clear the original gas pedal linkage horizontal shaft(if that is what you will use).
A recessed stock firewall looks much better than an aftermarket firewall. Either way, mock up the engine with everything in place; distributor, water pump, pulleys, fan, fuel pump, etc. so there are no surprises later. Here's a pic of a small recess I did on a '33 firewall to fit an unmentionable engine along with a pic of my kid's channeled '34 a pretty much stock firewall.
Thank you fellas. I’m using the hood no fenders. Is $500 good for a OEM firewall? I’m also looking for the outer side cowl sections.
Around here you should be able to buy a whole cowl for $500. Maybe in AZ prices are higher. I'd still rather have an original firewall with the least amount of cutting than a modern one.
grab a '35-'36 truck firewall... same size as a model 40 but has about 4" more engine bay... it retains the stock looking reveals / beadwork... a '37-'39 truck firewall is the same size but has a very handy battery box built in... pic... i like to leave 1" of the truck cowl in case i need a chunk of the factory looking fold over....
Wow I didn’t know those could work. Is there any modifications that would need to be made? Or figment issue?
Maybe without the belt driven fan? I couldn't have done it without the distributor recess, and I'm using an old point small diameter distributor.
My brother & I used a 1961 283 Chevy in his 1933 sedan, adapted to the original trans. We didn’t touch the firewall. We may have gotten creative with the fan, but I just don’t remember. We did the swap in 1979. I do remember that the fit was tight.