A standard 4 speed will easily take 150 hp in a road car. You are kidding yourself if you think you will get much more power than that from a 2 litre without spending a mint. Even 150 hp will not be cheap.
Others here are right in that they are barely worth rebuilding, you wont get much change from $1000 from a gearbox guy and for about $1500 you can buy a second hand straight cut close ratio box which is a huge improvement over the standard ratios (once you ar driven a car with one you will never go back).
If you must get a box built at least buy a close ration gearset so you will have something worthwhile once you have spent all your money.
Cheers
Shaun B
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