Wo-Nelly

I tried to search but came up with very little. Basically what I want to know is what is the safe range hp wise I can push my motor to. It's a H22 block with 89mm 9:1 cp pistons (+2mm making it 2.3L) with a stock head. All I've heard is basically don't push it too far past 400whp, but that was refering to a b-series and I'm assuming it's different on a h series, correct?

Wo-Nelly

someone's gotta know something, shed some light oh great ones

Bnjmn

that number is used to determine injector sizing, among other things
In what way do you want to use it?

Ben

Wo-Nelly

I basically wanted to know how far I can push with pump gas 93 octane.

PrecisionH23a

Correct.

The MSBC is also know as the Brake Specific Fuel Consumption (BSFC). BSFC is the ratio of the engine fuel consumption to the engine power output (as measured at the flywheel). Basically, it is a measure of engine efficiency. It has a lot to do with the combustion chamber design as well as the material the head is made out of.

The H-series engines are less efficient than b-series. This means you need to run higher octane to sustain detonation. B series have pulled off an easy 450whp on pump gas (93 octane) whereas H series motors will usually misfire around the 350whp range. Do not take it above 350whp on race gas though. Slowly but surely you will notice the motor will misfire as it makes more and more power. Gapping the plugs will also not help.

B series motors also have a stronger ignition system then the preludes do. Typically around 330-350whp the stock ignition will **** out on you. So if you plan on running more then 350whp, then do so on a higher octane fuel. 110 is a nice gas to use, I will be using 116 on my next dyno session with around 28psi.

I actually squeezed out 375whp on pump gas while on the dyno and right at 390whp you could not only see the misfire on the dyno chart but hear it. Once race gas was put in and the plugs were gapped a tiny bit close, there was an instant 20whp gain. Usually on the street I run 12psi on pump gas, sometimes I will throw in a gallon or two of 110 octane just for that extra sense of security though. And believe it or not, you can tell a difference when race gas is added... especially on highway pulls.

DaX

iTrader: (1)

BSFC is pounds of fuel per hour per horsepower. 0.50 is a good conservative starting point for guessing and tuning.

PrecisionH23a

That is truely amazing. I actually wrote that in my last post but I took it out since I thought it was a bit on the irrelevant side.

I guess thats why it takes 1484 HT members to change a light bulb

BSFC has units of grams of fuel per kilowatt-hour (g/kWh) or pounds mass of fuel per brake horsepower-hour (lb/bhp-hr)

Arturbo

This may or may not help: https://honda-tech.com/zerothread?id=727017

kpt4321

For engine limitation information:

https://honda-tech.com/zero...12630

Additionally, BSFC/MSBC doesn't really have an effect on the amount of power a motor can handle. It only concerns the amount of fuel necessary for a given outout.

IloveNewt

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PrecisionH23a &raquo;</TD></TR><TR><TD CLASS="quote">Correct.

The MSBC is also know as the Brake Specific Fuel Consumption (BSFC). BSFC is the ratio of the engine fuel consumption to the engine power output (as measured at the flywheel). Basically, it is a measure of engine efficiency. It has a lot to do with the combustion chamber design as well as the material the head is made out of.

The H-series engines are less efficient than b-series. This means you need to run higher octane to sustain detonation. B series have pulled off an easy 450whp on pump gas (93 octane) whereas H series motors will usually misfire around the 350whp range. Do not take it above 350whp on race gas though. Slowly but surely you will notice the motor will misfire as it makes more and more power. Gapping the plugs will also not help.

B series motors also have a stronger ignition system then the preludes do. Typically around 330-350whp the stock ignition will **** out on you. So if you plan on running more then 350whp, then do so on a higher octane fuel. 110 is a nice gas to use, I will be using 116 on my next dyno session with around 28psi.

I actually squeezed out 375whp on pump gas while on the dyno and right at 390whp you could not only see the misfire on the dyno chart but hear it. Once race gas was put in and the plugs were gapped a tiny bit close, there was an instant 20whp gain. Usually on the street I run 12psi on pump gas, sometimes I will throw in a gallon or two of 110 octane just for that extra sense of security though. And believe it or not, you can tell a difference when race gas is added... especially on highway pulls.</TD></TR></TABLE>

I have an h23 and i got it tuned on 93 to put out 375 whp and 405 ft/lbs of tq. The setup is a 8.8:1 Venolia pistons, ge sleeves, msd setup with hondata....yada yada all the other accesories. I am pushing 20-21psi on a small t3/t4b. I have yet to notice any detonation on 93, but i dont boost 21 psi much, more like 14 psi daily. Do you think i shouldnt push 375hp/21psi on pump?

PrecisionH23a

No you shouldn't. I got a little carried away on the dyno and it started misfiring right at 390whp. I would push no more then 350ish on pump gas. 10-20whp on the street is not worth pushing a motor to its limits.

IloveNewt

Does a higher octane reduce the cyl presure even if it wasn't det. at a lower octane?

kpt4321

That's a simple question without a simple answer.

Power is generated by cylinder pressure, but not just peak. What really matters is the pressure under the curve. When you raise your octane, the peak pressure may go down, but the pressure under the curve may stay the same, or possibly even go up. As far as I know, higher octane fuels will generate a broader curve, for the same conditions.

But like I said, there's no real answer without knowing more information, and even then I couldn't be sure.