Horsepower increase M42

[Gordo351]

Hello all, brand new to BMW's and I have a question. I have a aquired a Lotus seven style car with a BMW drive line in it. 94 M42, 5 speed stick, 3:45 posi rear end. Is there a quick and cheap way to bump the HP on this engine? Turbo is not an option the way the exhaust is. I am wondering about bigger injectors, cam shafts. Supercharger would be an option but cost is a possible issue there. Any advice is welcome!

Gordo351

[pbonsalb]

Look up grassroots motorsports 318i project car. Not quick or easy or cheap but they fully built a motor or rather had metric mechanics do it and gained a lot of power. I think the engine build was in the $8k range.

Could you fit a positive displacement supercharger on the side of the motor?

[Gordo351]

I could possibly fit one if I had dimensions, pics etc. My hood is handmade, a lot of english wheel work I would hate to give up!

[pbonsalb]

Try Hyde Motorsports. It will be prototyping an M42/44 positive displacement kit soon and should have some dimension estimates.

Swapping in a more powerful 2L four is another option. Boxer like WRX or in-line. Obviously turbo.

[jakermac]

I was toying with building a proper M42 based turbo motor, and after much research and budgeting decided it would be much too expensive and not get anywhere near the lower levels I was shooting for. I ended up changing my plan to swapping in a Honda K20A2 2.0 liter motor that I’m building to run a Borg Warner EFR 7163 turbo. And with the KMiata transmission adapter parts, I’m able to bolt the Honda Motor to my BMW ZF 5 speed transmission.

[cmoody]

Possible that there might be a few DASC kits running around still, but are probably expensive.

[digger]

racehead ITB kit, mild cam increase