14:1 CR in DD

[boostdelinquent]

I've been doing some research and found out my H23A1 w/ H22 Type S pistons will be closer to 14:1 CR instead of 12.5-13:1 that I expected. With that said, I want to get some feedback on ideas I have to make it feasible to run this CR daily w/out breaking the bank so to speak. There is a Sunoco about 2 miles from here w/ 100 octane but at 7.50ish a gallon, that is not a very feasible option. With that said, I was thinking of doing one of the following.

1) E85

This seems like a realistic option considering E85 has a lower heating value of 29.19, octane rating of 101.6 and stoichiometric ratio of 9. I think this would do the job pretty well however it will require a greater amount of fuel. Considering that E85 is cheaper than premium gas in most cases the saving may even out as well. The one downside is what happens if I decide to take an extended roadtrip and E85 is not available when I need to fill up, not to mention I'd have to find which gas stations have E85 locally.

2) 93 octane fuel w/ 1 gallon of Toulene added to each tank.

I also like this option. Since toulene has a lower heating value of 40.6, octane rating of 114.5, and stoichiometric ratio of 13.4 it's properties are similar to premium fuel which has a lower heating value of 43.5, octane rating of 91-93 (depending on area), and stoichiometric rating of 14.7. With that said, I could add one gallon of toulene ($10 @ most hardware stores) to each tank of fuel which would bump the octane rating up over 100. The only downside would be driving around w/ a jug of toulene for instances when I make a road trip and want the ability to just stop at any given gas station by the interstate and not have to look for a hardware store.

Those seem like the main options I have. For tuning I'll be using a P72 ECU running Crome-Pro as well as having a UEGO permanently installed in my car to keep an eye on the A/F ratios. Though the goal is a sustainable way to DD my car w/ this high of compression if I choose to. In the event it becomes too much of a PITA I can also always put in a thicker headgasket to drop the CR to between 12-13:1 if needed although I think 13:1 would be pushing it a bit on 93 and require pulling alot of timing IIRC. Anyway, what are ya'lls thoughts?

[d112crzy]

H23 vtec with type s pistons doesn't yield over 12.1:1 unless you're doing some other stuff to it to raise compression.

H23vtec with JDM pistons puts out 11.6:1 compression. It's what I have.

If I were you, I'd use nothing but "e10" 93(93 octane with 10% ethanol). It's much better than "pure" 93 due to the ethanol. Increase knock limit quite a bit, and is usually cheaper.

The highest I'd go on pump gas is 12.5. Anything past that is really pushing it, as far as trying to produce maximum power goes.

[boostdelinquent]

H23 vtec with type s pistons doesn't yield over 12.1:1 unless you're doing some other stuff to it to raise compression.

H23vtec with JDM pistons puts out 11.6:1 compression. It's what I have.

If I were you, I'd use nothing but "e10" 93(93 octane with 10% ethanol). It's much better than "pure" 93 due to the ethanol. Increase knock limit quite a bit, and is usually cheaper.

The highest I'd go on pump gas is 12.5. Anything past that is really pushing it, as far as trying to produce maximum power goes.

I'm using the H22 pistons in a notec H23. With that said the H22 pistons stick .016 out of the cylinder. As for the E10, do you know how readily available it is or is it like E85 where it's hit or miss depending where you live?

[d112crzy]

All Hess stations have "e10"(it's not actually called that). The cheaper gas stations carry it as well.

Also, H23 block is the same deck height as an h22. The piston sticks out the same regardless of an h23 or h22 block.

[tn_accords]

joser : you should post that link to the site where you can get a good estimate on numbers when calculating compression ratio and piston to deck clearance and all that crap.

[93F22A6]

HondaFan81 has 13:1 on the white project and he runs pump gas in it. Also you could get a gallon of 100 octane and then the rest be 93. That might work but I'm not to sure on that. 7.50 sounds a little high, I can get 110 up at the race track for 8 a gallon, and thats high at that moment.

[boostdelinquent]

All Hess stations have "e10"(it's not actually called that). The cheaper gas stations carry it as well.

Also, H23 block is the same deck height as an h22. The piston sticks out the same regardless of an h23 or h22 block.

Hmm, I was basing my info off of pirateMcFred's build on H-T. Part of the CR is also that the combustion chamber design of the H22 and H23A1 are different.

[d112crzy]

Yes, there's ~4cc difference. 50cc=h23, 53.5cc=h22.

Your compression isn't that high.

[HondaFan81]

HondaFan81 has 13:1 on the white project and he runs pump gas in it. Also you could get a gallon of 100 octane and then the rest be 93. That might work but I'm not to sure on that. 7.50 sounds a little high, I can get 110 up at the race track for 8 a gallon, and thats high at that moment.

More like 12.4 technically.

[nighthawk]

my caclulator puts a H23A1 w/type s pistons at 13.1:1 compression

[d112crzy]

Your calculator/specs are wrong.

[nighthawk]

Your calculator/specs are wrong.

provide some numbers instead of just saying everything is wrong.

[nighthawk]

the piston will sit .020 out of the hole.
head 50 cc
4.5 cc dome on type s pistons
.026 compressed gasket
= 13.1:1

[nighthawk]

H23vtec with JDM pistons puts out 11.6:1 compression. It's what I have.

you have less dome on the pistons and a bigger head chamber.

[d112crzy]

http://www.honda-tech.com/showthread.php?t=1232811

If you're using all those specs already, then your calculations are wrong.

If you use Cisco calculator, it is also wrong. I'm gonna have to send my version to a mod so they can update the one posted here. Also, Cisco's calc doesn't let you properly calculate for frank engines because it doesn't take into effect the difference in compression height on different pistons.