daver

I know some of you die hard hp fans are going to say just chip the bloody p28 if you already have one. But i'm going to spend way more time daily driving than racing, where those closed butterflies come in handy; and the lack of a knock sensor just seems to be bugging me. It will be a jdm b18c in an eg civic with only bolt-ons.

Here the info i have about knock sensors so far. It simply retards the timing if it detects knock, and the ecu ignores it in vtec.

Well, what are the causes of knock? Does it just happen to bozos who put too low of octane fuel in or are there other scenarios? If you manually advance your timing too much you could cause it i'd say.

Why does honda have it disabled in vtec mode? If you fill up on low octane and hammer it, and the computer ignores the knock, won't that be bad? Or does it only happen at low rpms? Well, the timing adjust ping check is done at low rpms in 5th gear while climbing a low hill. So i figure pinging/knocking must only be an issue at low rpms under load.

Is there any other danger scenarios warranting a knock sensor? Is there something inherent in high cr engine that need it? The lower cr engines have no need apparently. there is no danger of putting fuel lower than the recommended 87oct in... Is that the ONLY reason for it then? for dummies who put in the low grade???????

The butterflies.
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I've seen some dynos of chipped p28s and the low end looked comparable to stock p72s on this engine. But the p28s had gas guzzler race proggies. Would a gsr prog chipped p28 be noticably less power ful in the LOW END than the stock p72? Would the mpg be affected much by running the secondaries always open?

thanks

d

poison

I'd definitely get a P72 if you are going to daily drive it mainly because it can control the IAB's (that's of course if it's a JDM GSR B18C)

Knock sensor is when misfire happens and knock is detected, or ping. It's highly not likely running on a stock motor.

A chipped P28 and not having knock would not effect much of anything.

As for the chips, it just depends. I am not too sure. You would have to go on a dyno and find out.

daver

ya, it the jdm gsr b18c ( or the sirII or whatever) i'm looking at. I've already got a p28 sitting around, so chipping it would be simple and cheap; but those butterflies. You think it makes a worthwhile diff for sure in the daily driving low end poison? Have you tried both?

I understand i could get an msd rpm activation switch, but i could also sell my p28 and get as much as half the cost of a p72 and go clean...

d

poison

ya, on a B18C with secondary butter flies, it'll effect some low end. You'll notice it.

I'd probably just stick with the P28 and chip it, then go for a Skunk2 Intake Manifold.

daver

and that's another consideration, will i get bitten by the mod bug and go with some cams and a skunk2 down the road?

Would the skunk2 mani recoup some lost low end or make it worse? I don't hear any type R owners complaining about having no butterflies.

d

poison

Nope, you'll have some nice low end and have increased top end with it.

daver

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by poison &raquo;</TD></TR><TR><TD CLASS="quote">Nope, you'll have some nice low end and have increased top end with it.</TD></TR></TABLE>

hmm, really. I assume the low end with the p72 and butterflies closed would be better, but how much low end do you need with a 2200lbs car.

Is the skunk2 basically a carbon copy of the typeR intake mani (cept with the gsr bolt pattern) or is it more like a ported typeR mani?

poison

The skunk2 provides good HP numbers across the board.

It's basically an ITR manifold but flows a little better. You would have to research some dyno's between the ITR manifold and the Skunk2 though.

Both of them are very good intake manifolds.

AMG

Sorry to pop in on your thread, but Ihave a quick question.

Poison, I am not sure if you remember my recent posts about lack of fuel? I have a B18C motor and have a skunk2 intake mani. Anyways it is hesitant down low and people tell me to either chip the ecu or get a vafc. I would rather leave the reprogramming of the ecu to the end and get a vafc. If i get a vafc and get it tuned, people say to raise vtec to 5400 or 5500? I still am confused as to why because wont this hurt mid range even more by moving up vtec? And which should i do chipped ecu/p72/vafc?

Thanks in Advance

poison

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dohcVTEChatch &raquo;</TD></TR><TR><TD CLASS="quote">
Poison, I am not sure if you remember my recent posts about lack of fuel? I have a B18C motor and have a skunk2 intake mani. Anyways it is hesitant down low and people tell me to either chip the ecu or get a vafc. I would rather leave the reprogramming of the ecu to the end and get a vafc. If i get a vafc and get it tuned, people say to raise vtec to 5400 or 5500? I still am confused as to why because wont this hurt mid range even more by moving up vtec? And which should i do chipped ecu/p72/vafc?

Thanks in Advance </TD></TR></TABLE>

You don't usually want to raise VTEC, the only reason you would raise VTEC point is to have the smoothest and when the primary cam lobes are maxed out with out have a VTEC dip.

I would get a V-AFC first AND a chipped ECU. The V-AFC even on a stock mapped ECU will be good to tune and tune the A/F ratios thru-out the whole power-band for the best HP/TQ numbers.

Sounds like you just need a tune big time. Make sure you have an FPR, Adj cam gears, the V-AFC so you can tune the motor to the best at that point.

AMG

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

You don't usually want to raise VTEC, the only reason you would raise VTEC point is to have the smoothest and when the primary cam lobes are maxed out with out have a VTEC dip.

I would get a V-AFC first AND a chipped ECU. The V-AFC even on a stock mapped ECU will be good to tune and tune the A/F ratios thru-out the whole power-band for the best HP/TQ numbers.

Sounds like you just need a tune big time. Make sure you have an FPR, Adj cam gears, the V-AFC so you can tune the motor to the best at that point.

</TD></TR></TABLE>

Should I get a chipped ECU or the P72? I want this to be a quick everyday driven car without sacrificing too much of the comfort of driving. I'm not really sure which ECU would be the best because I don't know too much about chipping ECU's and the effects it causes.

Yeah that's what I didn't understand about rasing the vtec point and actually increasing mid range power by doing so. But many people thought that this would cure both the fuel and the hesitation down low. So frankly I don't know what to do.

Any more help on this that you could give me would be great.
-Dylan

poison

I would get the chipped ECU. Especially with the Skunk2 IM.

just get the V-AFC, take it to your local tuner with a dyno, and tell him you want it tuned with all the good parts

You'll pull some good numbers.