Jagolas

ok i have a 94 coupe with jdm d15b vtec. i also have i/h/e. exhaust consists of 2.25 madrel piping with high flow cat and dtm muffler. also have ngk iridium plugs, apc wires (i know they suck), msd cap, blaster 2 coil. the car doesn't seem to have the power that it should. i was told that basically my car is "breathing" too well and that i should either get a resonator, to increase backpressure or upgrade the fuel delivery. which would be better? i know gettin a resonator is cheaper, but well it help? and what would you guys recommend in upgrading the fuel delivery, besides nitrous?

redline32

as far as the fuel; I use a 255lph fuel pump...That might help

Jagolas

i was thinking of that, but i was also told to buy a adj fpr like b&m's with a guage in playing around with that. but then the injectors can only push so much.

Jagolas

anyone else?

Jagolas

anyhelp by anybody?

BauleyCivic

Get a VAFC and a B&M fuel pressure regulator and take it to the dyno and have it tuned.

Jagolas

ok, where we be a good place to get a vafc?

BauleyCivic

https://honda-tech.com/zerosearch

Search the honda-tech classifieds, I just bought one off of another member for $165 shipped.

More info on VAFC: http://www.sounddomain.com/sku/APX401A908

Jagolas

yeah just searched, how hard is it to tune these?

TeamNextGenChris

sounds like a lot of work and money for a basically stock motor.you may be able to tune a couple HP out of that setup with a regulator and VAFC,but it should run really well with stock pressure and stock maps-the mods you have are from extreme to the point that the stock tuning just won't cut it anymore.i'd go over the motor and confirm everything is in good working order-check your cam and ignition timing,make sure your plug wires are in good shape(i've seen plenty of cheap aftermarket plug wires have higher than spec resistance even when new)along with your other ignition components.maybe do a compression check to make sure there's no problem there.if you have access to a dyno,maybe a baseline run just to see what you're really putting out,and if it is,in fact,lower than it should be.
what ECU are you running?
has the motor not met your expectations ever since you swapped it in,or has the performance dropped?it could just be that you're expecting too much.i don't know what trim level your coupe is,but that motor in that chassis definitely isn't going to give earth-shattering results.
let us know what you find.
Chris

Grimm

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jagolas &raquo;</TD></TR><TR><TD CLASS="quote">ok, where we be a good place to get a vafc?</TD></TR></TABLE>

PM LSHatch

Jagolas

right now im runnin a stock p28, and the power has just never been there, after the swap. and i know that this motor should be able to produce more than my stock z6, but it's not there. and i realize that this motor isn't earth shattering. i just think that it should be able to keep up or beat my 240sx, and it's nowhere close. compression was done during swap and that was fine. i plan on doin a vaccum check this week, along with an exhaust leak check. but it's still like something is holding me back. and the closest dyno is an hour away and cost like 400 for maybe 2 runs (i think).

TeamNextGenChris

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jagolas &raquo;</TD></TR><TR><TD CLASS="quote">right now im runnin a stock p28, and the power has just never been there, after the swap. and i know that this motor should be able to produce more than my stock z6, but it's not there. and i realize that this motor isn't earth shattering. i just think that it should be able to keep up or beat my 240sx, and it's nowhere close. compression was done during swap and that was fine. i plan on doin a vaccum check this week, along with an exhaust leak check. but it's still like something is holding me back. and the closest dyno is an hour away and cost like 400 for maybe 2 runs (i think).</TD></TR></TABLE>
also check your timing and ignition components.
i just installed the same motor in my friend's EK with a P2P(OBDII EX ECU)controlling it.the car seems dead until the VTEC solenoid activates.from what i understand about this motor,it runs on 12 valves some of the time.i'm assuming the second VTEC solenoid activates the other four valves.since the P2P(and P28)only have one circuit to activate the solenoid,i just wired them both to that one circuit.now VTEC and the four additional valves all activate at the same time.i'm thinking that the four valves should activate much earlier,as the car has no midrange...my friend hasn't found any good info on how the two different solenoids are supposed to be activated.i'm assuming the only correct way is with the appropriate JDM ECU that i'm assuming has a circuit for each of the solenoids to activate them at different times.
does your car feel down on power all the way to redline?or,does it feel slow until VTEC kicks in?
also,i wouldn't really expect hardly any power gain over a Z6-the peak power and torque specs on both are almost identical.if anything,i'd say the D15 would have less torque across the board due to it's slightly smaller displacement.
Chris

Jagolas

k thanks for the help. well here's the update, i bought and plugged up my a/f gauge, turns out im runnin way rich. like at wot the gauge(autometer)is at the c in rich. so im not gettin enough air. that could be bc of the 4 valves like chris said. i am thinkin of gettin a chipped p28 from an ht member. plus i have a ls tb in the garage, so i will try and install it. any other ideas? i know that should buy im, but i really want to save money to buy or finish a swap to b series.

Jagolas

and yes it seems like there is no power till vtec kicks but gets stronger right up till redline

Tad

you're thinking of getting a chipped p28??

what ECU are you running currently?
if its the stock one for your car.. then thats probably your problem.

but uhh.. get some friggin oem wires man,
aftermarket wires suck.. but APC!?!? come on

you dont need a new fuelpump

Jagolas

yeah that's my stock ecu, but this is the first i have heard of jdm d15b's not workin right with p28, i know the apc's suck, but i bought them when i was very new to the import scene.

TeamNextGenChris

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jagolas &raquo;</TD></TR><TR><TD CLASS="quote">yeah that's my stock ecu, but this is the first i have heard of jdm d15b's not workin right with p28, i know the apc's suck, but i bought them when i was very new to the import scene.</TD></TR></TABLE>
just to clarify-do you have the OBDI 92-95 JDM D15B(the one that's basically a Z6 head on a D15 block),or the 96+ OBDII 3-stage VTEC D15B(that runs on 12 valves,and has one solenoid to activate the other 4,and one to activate the VTEC lobes)?
Chris

Jagolas

sorry for confusion i have obd1 jdm

TeamNextGenChris

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jagolas &raquo;</TD></TR><TR><TD CLASS="quote">sorry for confusion i have obd1 jdm</TD></TR></TABLE>
okay,so the P28 should work pretty well for your setup(i was under the impression you had the 3-stage VTEC OBDII D15B).do the things suggested above,and try to track down your problem.
Chris

Tad

so you have an ex then?
with a p28?

or ist he p28 you're talking about, the skunk2one you are GOING to get?
basically waht ecu do you have in your car currently?!

Jagolas

p28 (that's what i have now), yeah it's an ex.