Hello~

This is my first post in the all-motor forum so please bare with me. I am looking for guidance on my JDM B18C motor that is currently in my Civic EG that I use at HPDE schools.

The current mods are as follows:

AEM Short Ram, Comptech Race Header (JET HOT coated), no CAT mated w/ 2.5 true exhaust, bored throttle body, carbing oil catch can, CTR crank pulley, no AC/PS, Megan Racing cam gears, Skunk 2 stage 1 cams, Hondata IM gasket, NGK blue wires, AEM FPR, B&M fuel press gauge, and I am using a full standalone programmable Microtech ECU.

My tuner is telling me the power is dropping off in the higher RPMS due to lack of compression. My dilemma is how to increase compression in my motor safely. I am looking at either going with a set of CTR pistons OR maybe doing a mugen headgasket and milling the head slightly.

I want some direction on where to go with this setup. Currently the car made 195whp corrected and the power is dropping off greatly per the tuner (i wasn't there at the time of the dyno runs were made).

Thanks gentleman,

mike

 

still on pump gas ? how is compression ? the easiest route is to get new cams with better top end. but i would stay away from ctr pistons in a b18c set up.

 

compression now is stock and measured a few months ago with 240 across board. I am running pump gas 93 octane and intend to stay this way. The tuner told me the power is falling off starting at about 7500 rpms all the way up to about 8500. I would like to rev out and make power till about 87-8800 rpms if possible.

mike

 

with compression numbers still good, i wouldn't want to tear down a good, strong motor just for better top end. maybe a cai ? or mugen hg ? agressive cams is out of the question with stock comp. but i would rather get new pistons before milling of the head.

 

Flat face valves, thinner head gasket and milling will all raise compression. Ctr's have a garbage quench area, I would work on the top end of your motor and not worry about the bottom half.

 

Obviously we need some info on how the car is performing itself as well how is it doing on the track? Obviously you are looking for more top-end power but how is your midrange? I am confused as why you are wanting to rev that high, 195 hp isnt terrible for what you have, is this the type-r b18c or is it the gsr version?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ZacCarter &raquo;</TD></TR><TR><TD CLASS="quote">Obviously we need some info on how the car is performing itself as well how is it doing on the track? Obviously you are looking for more top-end power but how is your midrange? I am confused as why you are wanting to rev that high, 195 hp isnt terrible for what you have, is this the type-r b18c or is it the gsr version? </TD></TR></TABLE>

The car has a great midrange with the Comptech stepped race header (4-2-1). On the track it has great power up till about 8k rpms where at the top of 4th gear it definitely falls on it's face and the motor sounds like it is about to die trying to rev that high. The motor should be revving out to 8400 rather quickly in a &lt; 2000lb car. The reasoning I would like to rev out a few hundred RPM's higher is due to some high speed sweeping corners in my local tracks that I don't like shifting in between.

In the conversations I have had back and forth today with my local shop it seems there line of thinking is that the car won't be able to run on pump gas if we were to raise the compression a half of a point (with Mugen headgasket and slight mill of the head). The CTR pistons would bring it up to 12.5 or so I am told which isn't the best idea to use pump gas. I MUST use pump gas so I am leaning towards a Mugen headgasket and milling of the head slightly. Thanks for the replies thus far

 

I was gonna go with itr pistons in my 97 gsr, similar set up, instead i went with blox type b cams, rocket valvetrain, golden eagle cam gears, bolt ons, but only with a chipped p28. Trying to get time for a real tune. Blox pull hard top end, but mid-range isn't as aggressive as bc3 or bc4.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EleanoR &raquo;</TD></TR><TR><TD CLASS="quote">
The current mods are as follows:

AEM Short Ram, Comptech Race Header (JET HOT coated), no CAT mated w/ 2.5 true exhaust, bored throttle body, carbing oil catch can, CTR crank pulley, no AC/PS, Megan Racing cam gears, Skunk 2 stage 1 cams, Hondata IM gasket, NGK blue wires, AEM FPR, B&M fuel press gauge, and I am using a full standalone programmable Microtech ECU.

My tuner is telling me the power is dropping off in the higher RPMS due to lack of compression. My dilemma is how to increase compression in my motor safely. I am looking at either going with a set of CTR pistons OR maybe doing a mugen headgasket and milling the head slightly.

I want some direction on where to go with this setup. Currently the car made 195whp corrected and the power is dropping off greatly per the tuner (i wasn't there at the time of the dyno runs were made).
</TD></TR></TABLE>

I'm having the same problem with a similar set up, my motor stops making power just over 8000 rpm with the same cams. I'm thinking of going with JDM ITR or CTR pistons, flat face valves, and S2S2/Blox B cams next.

 

I talked to Clay @ King Motorsports and we are going to try a couple of different things in conjunction with my local shop to cure this problem. I only relay this information as I suspect it will help to cure my problem. I am going to change the intake from a hot air to the full cold air setup. I am also going with the Mugen HG and 20 thou off the head and re-tune. We should be making around 210-215whp soon enough

 

A different intake manifold such as a VictorX or JG sheetmetal will move your powerband up in the RPM band at the expense of low/mid range power. A ported ITR intake manifold will improve your power everywhere. Larger cams will also move the powerband up.