[pinota]

After 3 months of the CTR 12.1 CR failed rebuilt i got my car back.
Already have 750 miles on it and it´s great.
Running right now at 55 psi and 13º timing base during breake in cause i don´t want to have any problems, like detonation.

I´m runing 11.5 CR 82.mm pistons and eagle rods, the head and block were decked in a total of 0.023 inches. ( stock injectors but 98 octane gas )

Now my question is from 750-1000 miles how to drive my ITR, i drove very slow so far.
About fuel pressure and timing should i raise my FPR and keep the 13º timing or raise it to. I´m running stock 240 cc injectors.

Thanks,

Pinota

 

[IntegraBad18c]

There are articles on this...

That's 55psi fuel pressure, right? Had to ask. I don't think with stock timing that you would run into detonation problems. The proper octane can fix that by controlling the burn rate.

 

[MichaelDelaney]

there's an article on how to break-in a new engine properly in the Articles' Performance Engine Internals section..click the Articles on the menu to the left side of the page here.

So with a 23 thou milled head your about 11.87:1 CR. I suggest you crank up the FPR to 60 psi (set with the IM vacuum line removed off the FPR) which would give you a little more flow rate than a Prelude 280 cc/min injector at 42 psi..287 cc/min to be exact. You can run stock timing like 14-15 degrees to start if you want to play it safe...it's not like you had those crazy CTR pistons with 12-12.3:1 CR.

You'll likely need to upgrade the injectors in the future especially if you are running aftermarket cams.

 

[MichaelDelaney]

BTW 70 psi (vacuum line off) will give you a 310 cc/min flow rating but exceeds the 20% max rule for cranking up the injectors without shortening the injector life and throwing off the fuel calibrations on the ECU fuel map program. 65 psi or your max adjusted FP (stock is 44-55 psi and 20% more than 55 is 65 psi) will give you 299 cc/min.

 

[pinota]

Thanks for the info.

I´ll see how my a/f is tonight, cause i´m gona install the Greedy a/f warning metter.

 

[Mello]

I have a 99 gsr, i'm planning on adding some ITR JDM pistons, I've heard the cr will be raised to 11,4:1, is this true?! if so will a need to use high octane gas like Airplane or VP, also im thinking of some cams, like Skunk2 II, or Crower 402, and some p&p to the head or will it be to risky due to the high cr and cams?

 

[sleeperls93]

Are there good Honda engine builders in la Republica Dominicana

? The compression is 11.0:0 for the ITR pistons; I have crowewr cams, I personally love them, most people will probaby tell you to go with the skunk2s or some jun cams. That's funny about the gas, your not serious, right? Jetfuel? Good luck getting good gas in DR, third world...

 

[MichaelDelaney]

just use 93-94 octane , break the engine in correctly, and tune the damn engine before you thump on it. that means tuning with a wideband O2 sensor on a dyno....with someone who knows what they are doing. Yes the JDM ITR pistons in a GSR is about 11.4:1 CR with a stock head gasket. I would start at 14 degrees BTDC spark timing, #7 plugs gapped at 0.040 in., and crank up the FPR to 60-65 psi as a start during break-in as a safe setting and then tune from there.

I'm running 11.9:1 CR on pump gas....

 

[Mello]

Are there good Honda engine builders in la Republica Dominicana

? The compression is 11.0:0 for the ITR pistons; I have crowewr cams, I personally love them, most people will probaby tell you to go with the skunk2s or some jun cams. That's funny about the gas, your not serious, right? Jetfuel? Good luck getting good gas in DR, third world...

Yes we have good honda builders down here and about the fuel, sure i can get jetfuel, just got to have some conections

 

[99_tegls]

Are there good Honda engine builders in la Republica Dominicana

? The compression is 11.0:0 for the ITR pistons; I have crowewr cams, I personally love them, most people will probaby tell you to go with the skunk2s or some jun cams. That's funny about the gas, your not serious, right? Jetfuel? Good luck getting good gas in DR, third world...

I don't think he meant Jetfuel as in JP-8 which is a mix of Diesel fuel and Kerosene I think he was talking about Avgas which is like 108 octane but 5 bucks a gallon.

 

[MichaelDelaney]

there's no need for that. you can run with 93-94 octane pump gas even with 12.3:1 cr as long as you fuel it right in terms of air fuel ratio tuning.

cheers