civic_jason

I'm planning a future swap for my ek and I was interested in knowing what mods to make without hurting gas mileage?

The only exceptions I have are that I plan on using a LS intake manifold which I may port on a little and an LS automatic (local shop is very good at doing the auto swaps)but besides that I'm open to suggestions. Oh and always more power and mpg is always a good thing.

TM_EM1

seriously? LS automatic?

i have a B20v with a stock b16 tranny making about 27 mpg with very spirited driving. I usually stay out of vtec though and i'm pretty sure with a LS 5th i'd be around/over 30 mpg.

a conservative turbo setup with a great tune might be even better.

civic_jason

Yes auto this is my commuter.

Turbo is out of the question due to the 328,000 miles on the engine.

I might go turbo on the B20 one day.

I figure keeping the exhaust to about 2 to 2 1/2 inches won't hurt mpg. I plan on a adding the usual air filter and piping. I'm a bit concerned about the P75 ecu running the B20 a little too lean so I may have to get a tune.

civic_jason

How much does intake porting help?

Is the stock throttle body my best option?

Does head porting help? Exhaust side or intake side? Or both?

Stock exhaust manifold or is there a better aftermarket for a close to stock engine?

Come on people I know there are some of you that know this stuff backwards and forwards.

hybridmiklo

If you are worrying about gas mileage and doing auto swap. Just stay stock. You are going to be wasting alot of money for nothing.

stayontrack

manual transmission for better gas mileage

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civic_jason

No way I'm staying stock the 1.6 is just way too weak.

I think you misunderstand. I don't want fast I want more torque, more power and just as good mpg. If I wanted fast for cheap with zero worries about mpg I would have kept my 87 Mustang LX 5.0L.

Please tell me how much worse the LS auto would be mated to a 2.0L than a D16y7 mated to an auto then I might change my mind.

The B20 swap isn't going to be that much more expensive than it will be for me to swap in a y8 with auto.

civic_jason

I don't want a manual...I'll take a mpg hit there to keep my auto.

jazzRS

i hate to say it but just scrap this whole idea. a b20 with over 300k miles mated to an auto? just dont do it. i bet a healthy d16 will be better than that tired b20. save money and time and do this right or dont do it at all

civic_jason

No the d16 has 328,000 miles now. I plan to purchase a low mileage b20 and auto.

I really don't see how a 135-165whp b20 (don't forget the torque!) with auto could possibly be as bad in any respect than a rebuilt d16y7 or d16y8 that makes maybe 85whp/100whp through their automatics.

civic_jason

So which is best for the B20z engine to port the intake or the exhaust side?
Also I'm interested in knowing if porting the LS intake is a good idea or will kill my torque?

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