98tadriver

I read a few things such as the higher compression jdm f20c making 250ps (246hp) @ 8600 rpm where as the usdm f20c1 makes 240ps (236hp) @ 8300 rpm.

My question is, has anyone actually dyno'd both of these, and if so, what was the actual difference in hp/tq at the wheels? Does the jdm engine make 10 more hp at the wheels or is it negligible? Just curious is all. Thanks

98tadriver

Holy crap. 70 views, not one reply

liquid_helix136

As someone who has owned an s2k and been active here for about 8 years, I've never seen anyone seek out JDM engines specifically for the compression increase. The F22 tends to dyno higher than the F20s, and if you were going to do a swap, I would recommend the F22 vs the JDM swap.

s2000Junky

Agreed F22 is just better in every way, power and machine tolerances/equip improvements. .5 compression improvement on the F20 still wont match a USD F22 in power/trq overall. You will get slightly better yields out of an F22 with the same bolt ons as well, simply do to the added displacement/improved breathing through more of the rpm range.

Sylvain2000

Still doesn't answer the question ...

Interested as well ,

kenstyle

You're not getting any real replies because honestly, this is such a trivial and silly topic to discuss with all the aftermarket support that is available out there for the USDM F20C.

Hope this helps.

98tadriver

Thanks for the replies fellas My engine runs good and all; It was more of a question to satisfy my curiosity.

Chuck S

Japanese horses are smaller than USA horse so it takes more of them to match the power of the US engines. Kinda like the reverse of gas mileage US vs UK where they always get more miles per gallon 'cuz their gallon is 20% bigger.

-- Chuck

liquid_helix136

I had a low cr 2.0 engine built for boost, 9.5 compression, and had it tuned N/A while I saved up for boost. It put down 212whp and 147wtq. It had valves springs retainers and lighter pistons and rods but just simple bolt ons and tuned. Very strong engine.

my point is that was a "stronger than stock" engine, and the compression was 3x lower than the difference between the JDM and USDM engines, so that extra 0.5 of cr probably will be negligible and not noticeable.

Buy a test pipe and get it tuned, you'll gain 20-30 mid range tq which would stomp all over a JDM "high cr" engine

Bruunz

Another thing to think about is the fact that JDM engines have 100 octane fuel readily available. Which is why most of the JDM engines have a higher CR.
In Australia we always get our engines with a lower CR (usually by 0.5) as the highest common grade of fuel is 98 (93 US).