Honda Prelude Forum - PreludeDriver.com

Well....here it is almost 11pm and I just finish the Alternator swap in the 1990 si....at any rate I can't imagine what the dealer ship charges to deal with that nightmare....if it dies again I think I will relocate it to the trunk and attach it to a hamster wheel....Its odd but Ive never cussed Honda until this alternator....lol.

Next question!!!! Guys it seems odd to me that the temp gauge in the car gets about 3/8 in from HOT before the fans kick on? When they do however it cools right off and goes back to the halfway point between C and H....Can you give me your experience on the matter?

Also does anyone know of actual horsepower gains by ditching the factory air plastic/maze/intake/contraption? I know it looks much better, but just wondering if it is worth fooling with?

Hats off to Guido...thanks again for all the help. I think I am well on my way to making a nice car new again....thinkin about just keeping it stock for the most part.

Your temp gauge sounds like it is behaving like mine. That's probably normal. The important thing is that the fans are coming on, so I think you're good.

I don't know of anyone who has actually taken some quality dyno numbers before and after messing with the intake setup. The basic premise for airflow into an engine says that smooth, laminar flow from a cold air source is always best. To that end, I propose that a cold air intake would offer at least a minimal improvement over the stock system just because the flow path and surface is better. The inside of the stock air pipe is ribbed, which is no good for laminar flow. If there are improvements, and I think there should be, it would be mostly at the top end when the engine is really pulling air.

I built a cold air system for my car, and noticed an improvement in throttle response. No word on actual power output though, as I didn't put up the cash for time on a dyno. Sound improved as well, as all Honda engines make a pleasant roaring sound through the intake when they get above about 4000rpm on open throttle.

Bottom line, and what I tell everyone: If you have a hundred bucks lying around, not a bad thing to do. Just don't get into the intake expecting 10 extra hp, because it's not going to happen. I'm convinced that the actual increase might be in the neighborhood of 2-5 hp at the top end, but again, I can't verify this. Like all import engine tuning, you have to nickle and dime your way along. These engines are so good to start with, that unless you're going to do something severe, like put on a turbo, 2-5 extra horsepower is a good deal. It's so different from a big american V8 built in the 1970s that will make 30 extra horsepower just by slapping on a $150 set of headers. If only it was still so easy to free up some more ponies.

Glad to hear your car is rollin'. Post pics in the prelude Picture thread in the Just For Fun forum so we can see your ride.