I want your advice fab guys

I'm planning on using a K24 in my Rx7 and I know I can fab an adaptor plate to use my stock FC trans

what i really want to know is say my adaptor plate is 1/2" aluminum Could I have a shop Mill 1/2" off the transmission Bell housing and have the " adaptor" plate welded to the transmission Bell housing.

I can potentially save $500 On a custom Flywheel I know it'll most likely end up costing around $500 for the milling and welding but i'd rather the engine sit 1/2" further back and not have a custom flywheel

Will the Old Cast transmission aluminum be ok to weld?

 

No, no and no.......LOL

You can mill the front of the FC transmission and if you can find a "great" welder, maybe weld on the adaptor plate. The issue is the section thickness of what is left of your FC bellhousing and the difficulty in getting a good weld on it. It just isn't thick enough to maintain strength especially if you are going to get power out of that K24. Also, welding cast aluminum is extremely hard and it is very easy to substantially weaken the joint.

I am not even going to ask why you are going to do this as you can get as much power out of an NA 13B as you can out of a K24 and keep everything Mazda. I just don't understand why?

All I know is that I have run against a ton of K24's and even K24 Frankenstein motors over the years and only a couple have been substantially quicker. To each there own, but if I was going to swap in a motor and build a "one-off", I would go with an LS1 swap. A substantial difference and a car somebody else would want after you are done with it. A great swap, easy and a fast car when you are done. man it could idle at 160 kmh if you wanted it to.

Eric

 

I can make 250whp with a K24 and more Torque than a 13B and be Totally streetable and get decent gas mileage Lots of K24s out there for cheap etc etc etc

Right now the gas mileage and daily drivability is what swaying me to the K24 I'm not about to spend 6-7k on a LS1 Swap

Ya i didn't even think about the section thickness where the plate would be welded, it would be Quite thin

I would love to keep it all mazda with a Speed3 engine swap but that would truly be an expensive swap

 

just get a mazdaspeed protege.

 

If i wanted Front wheel drive car?

 

if gas mileage is such a big concern, i would just buy a cheap daily driver like a protege/civic and it would probably cost less than the k24 engine and all the modifications you would need to do to your fc.

it sounds like you need to make your rx7 a weekend/cruising/track car.

just my 2 cents, but it isn't worth the money/time/aggravation to do what you are planning.

 

^This.

 

Gas mileage isn't the concern and not the point if this thread I want to make more power than an n/a 13b without going turbo and the heat that it brings in a small light weight package with strong aftermarket support