Best/cheapest/most reliable etc way to 300hp

[JRowe]

Well, the title pretty much sums it up. Within the next year to year and a half, I will be attacking the power problem with my car. I currently have a couple of e30's (91 318is and 88 325is). The body is shot on the 88, so I will intergrate them into one car with the following parts I already have, most of which are already on the 88 325is. FK springs with bilsteins, all new suspension bushings everywhere, some urethane, new tie rods, short shift, Top end perf. regrind cam, chip, CAI, m30 afm. So I have addressed most areas that are easy to improve. Now I'm left wanting more power.

My goal is to have approximately 300hp or 250 rhp or something close to it. I've read the comprehensive swap thread for m50/s50/52 and it sounds like a good way to go. However, to get to 300hp, it sounds like one would need an s52 obd1 with cams, chip, intake exhaust and very good tuning. Cost would probably end up being 6-7k. So, what other formulae are available for 300hp. I know forced induction/turbo is a good alternative, but I don't know enough about it.

Please discuss, the pros and cons of the s52 route vs. turbocharging including costs, complexity, reliability etc. Thanks.

PS Since this doesn't fit neatly into this category, I will double post it in the forced induction forum also. I wish it could appear both places and concurrently update itself. Mods, if so can you do it? Thanks.

[PeterCip]

You can get 250 HP to the wheels relativly easily with a turbo M20.
Go a t4/t3 hybrid turbo, MS or equiv fuel system(or a RRPR) bigger fuel injectors, timing retard, intercooled.. etc etc.

anyway, a lot of us turbo M20 e30 guys put down that kind of power, for a lot less than an s52 modded.

But there is something about all N/A engine power...

[bmwdude]

The cheapest way to make 300hp is quite obviously turbo charging your M20 assuming it doesn't need a rebuild. To put things into perspective, a T3/T4 turbo with 5.5 psi and fmu, and small intercooler, with everything else absolutely stock, including exhaust, will give you about 230-235 flywheel hp on the 2.5L M20. A couple more digits on torque. This about the same range as a stock S52. Now a turbo gives you that flexibilty to increase power easily. If you were to increase boost to 10 psi, add your choice of either piggy back fuel system or stand alone(an other topic perhaps), T3/T4 turbo or even T04E, will give you 290-300 flywheel hp with 315-325 ft-lbs of torque, on an otherwise stock engine. The same figure as a stock M5 6 cyl or Euro E36 M3, although your turbo M20 will give an edge on torque. A cheaper alternative the M20 is.