Bolt ons...discussion

AFAccord

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The two motors spin in opposite directions. Therefore, K20 wrist-pins are offset .010" to the exhaust side, and F23 wrist-pins are offset .010" to the intake side. If you didn't flip them, THEN you'd run into the issues you mentioned. Flipping them 180 corrects the offset.
 

mraw112

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That makes sense. But Ive heard of people with like old ford v8s rotating the piston and it helps the gain a little more power.( im guessing through compression.). Since we dont have a high reving engine wouldnt it make it some what ok to have the offset in the other direction, and combating the increase in compression with a thicker hg?
 

AFAccord

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The old V8's had much more dramatic offsets with their wrist pins, so flipping the piston has a 'rod lengthening' affect. This creates a smaller compression area, and bumps compression up a little. V8's however use comparatively lower compression and much less aggressive timing than our fours. (Even Nascar engines are limited to 12:1 compression. Pretty low in comparison to most high-performance Honda builds) Most V8s have flat or dished piston domes, and can afford to be closer to the cylinder head. Not quite the case for our I4's with domed pistons. It's these extra tight clearances that distinguish Hondas from other cars.

The offset pins are intended to reduce side load on the cylinder walls and increase leverage during the power stroke when the explosion above the cylinder is forcing the rod down to turn the crank. Generally speaking, you wouldn't want to decrease compression with a thicker head gasket unless absolutely necessary. Doing so decreases quench area, which inhibits flame travel, and reduces cooling on the piston because it doesn't come as close to the head to transfer its heat into the coolant flowing above.
 
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talontsiawd

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go v6. i regret not doing it myself

You still have to do a transmission swap though. Not that i haven't thought of selling my my car for a v6 to do a mt swap asap, unfortunately most my mods are I4 specific.





It's funny how this went from a thread where i wanted to know the most basic and it got so technical. I love it though, it's probably basic info for alot of you guys but i know very little about building hybrid motors out of our I4's.
 

champaned_out

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hey AF Accord you were the one that hit 15.2 on the 1/4 mile a few years back right? with just bolt-ons and JET ECU flash?

your in this old school thread from a few years back on e-h.com... post #237 on page 24... there used to be a picture of your dyno plot but i guess after all these years the IMG expired or was taken off...
http://www.everything-honda.com/forums/showthread.php?t=5075&page=24&highlight=accordian

would you recommend the jet flash for people with bolt ons?
 

AFAccord

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hey AF Accord you were the one that hit 15.2 on the 1/4 mile a few years back right? with just bolt-ons and JET ECU flash?

your in this old school thread from a few years back on e-h.com... post #237 on page 24... there used to be a picture of your dyno plot but i guess after all these years the IMG expired or was taken off...
http://www.everything-honda.com/forums/showthread.php?t=5075&page=24&highlight=accordian

would you recommend the jet flash for people with bolt ons?

I would recommend the Jet reflash to someone who has covered all the basic bolt-ons, has a pretty tight budget, and low technical expertise.

It seems to provide equivalent results as a VAFC, but without the wiring headaches, and without the extra $$ to dyno-tune. I'm sure you could get even more gains by combining the Jet ECU and a VAFC, but for the cost of both items and time spent tuning, you could have already gone OBD1 and opened up much more potential.

I do still have my Jet ECU in the garage, and have a couple dyno charts here with the ECU in my own car when it was 'stock'. Mods in the first chart were AEM intake, header, H23 trans, and AEM PS pulley. Second chart includes the same mods, but with the OEM intake arm and a BLOX Velocity stack, and about 20 degrees cooler weather.

JasonHart.jpg


IHPTDyno.jpg


On a rather sad note, I'll soon be clearing out my garage and parting out the majority of my F23 parts... :(
 
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