Finally got everything installed on the car and got it on the dyno to see where i stand with things prior to putting the car back in storage. I wanted it done now so that i could get a feel for what parts i would need to order etc. before spring so that i'd know what i'd need/have a budget and plan to have to ready to go come May.

current relevent mods-

hps gen I kit
split second psc1-003 in place of the voltage clamp

Car runs very well in some parts of power band, but "breaks" up and hits some kind of an electronic fuel cut or something in others. Any rpm's over 5k or so are likely to trigger this (most likely due to pegging the maf), also often this happens if you aggressively get into it in the mid range (pegging the maf possibly?).

Additionally, it runs lean throughout the entire rpm range (for my taste). It seems that it is likely the ratio which the 02s are trying to regulate it to. Split second makes a scaler which will allow me to adjust this if i want to (now that i know i'll always be in closed loop) and i may want to go that route.

All that said- the car made very respectable power given the issues and i can definitely see some crazy numbers just around the corner...

my plan (please give me feedback)-

add fuel pressure gauge so i can determine if it is truly the 02s limiting my fuel rather than pump or injectors

buy a new maf sensor (i can get jus the sensor right? part #?) and test it with that installed to see if that fixes the driveability. Also, custom build a larger maf housing such that i'm not pegging the meter quite so easily... Another option here might be to buy a larger meter from an w211 e55 or something (do they share the same sensor plug?) as with the scaler i would be able to adjust that to "fit" what the stock ecu expects to see if necessary.

consider adding split seconds lambda scaler- hopefully, based on the results of more dyno time with the maf issue resolved and the fuel pressure gauge installed.

thanks for any help/advice

-drew

 

Current dyno #'s?

 

they are awful meaningless right now-

i don't even have a run where we were "in" the gas the whole way.

it made 320 lb lbs or so and 280 hp (at under 5k rpms) with 14.5 a/f ratio (in closed loop). this was on dyno dynamics- so very conservative as well.



Who has some ideas/help for me?

will newer E55 maf basically wire it in and allow me to "scale" from there?

are other peoples fi projects staying in closed loop always (i new this could be a problem)- what have you done to get away from the 14.5?)

-drew

 

You need to talk to NitrogenBalance on this forum. He also has the HPS system on his C43.

I know he has his car running real well with little or no engine related performance issues.

Jeff

 

yes, but he is also ok with having no control over his tuning etc. etc.

his maf is clamped at 4.9

he will need to solve some of the same problems i'm getting into solving now if he wants to run the power i want to get to as well...

i've been talking to him a bunch and am very thankful for his help- his experience leads me to think that my current major issues are due to my maf being bad. However, my larger issue with the closed loop/open loop stuff is also apparent in his tuning (although, his car did hit a slightly less lean ratio out of the box, so to speak).

basically, if clamping the maf signal is all it takes to make it work now- so what. I KNOW it won't be all it takes if i want to add another 100 hp on top of that- which i eventually will want to do.

I will be starting small in trying to pinpoint the issues (with a new maf) and it will likely "solve" all the apparent issues- but i want to set myself up to be able to make over 400 at the wheels...

-drew

 

i'm going to drive the car some more today and attempt to better describe the current "real" issue (leaving the a/f issue out of since the solution to that can come later/isn't part of getting the hps kit to work as it was meant to)


has anyone had a bad maf on a na or fi car exhibit similar characteristics? the stuttering in mid rpms and at times at the top end... usually triggered by rapid throttle increases? This with NO check engine light?

-drew

 

Absolutely. My car exhibited the symptoms for months before the check engine light came on. When the light finally did come on, it would stay on for a few days and then shut off, only to come back on a few days later. Bought a new MAF insert and the car has been running strong ever since.

 

update-

had to work on my WRX the last two weeks, but got things sorted out with it once again. it's making 264 awhp now on dyno dynamics which is a bit of a power loss, but the new turbo is much more driveable and the car feels faster overall. for those who don't know that's about 300 hp on a mustang dyno, lol.

so, back onto this-

purchased a late model E55 maf and plan to purchase a new sensor for my maf housing as well- i'm 98% sure at this point that my maf is dirty and causing my "issue" (cleaning it corrected the issue quite a bit, but not completely).

Once i do that i'll be adding fuel pressure gauge and larger fuel pump then determining need for larger injectors and/or lambda tuning. I'm not going to give up with it running 14.0 or 14.5 under boost- as i will soon be trying to turn boost up and will need full control to get it as low as i want.

will keep everyone informed.

 

Awesome, keep at it. The upgraded fuel pump and FMU should be enough to get it running right. Beyond 5psi is unknown territory for this kit. Very possible just don't know if the injectors will keep up.

I would highly recomend an electronic f.pressure gauge so you can read it while driving and such. Simple T into the line and run some power.

 

You're getting there! Good job.

However on a side note the C43 and W210 E55's use the same MAF.

 

ya, i got w211 maf

no idea how it will work, but i got it super cheap and i think the housing is larger.

fuel pressure gauge is on the top of my list of things to get right now too-

-drew


thanks guys

 

we absolutely do not have a fuel pump in-tank correct? we only have the external pump?

I'm going to go ahead and order/upgrade my fuel pump soon preemptively since my stock one has so many miles on it.

I've been talking to aeromotive and know which pump i will use depending on whether or not we do have an intake pump- i have found nothing anywhere suggesting that we do have one, but don't have any experience with late model cars which don't...


also, our cars have a true return style fuel system- right? I know i have a return line in the rear, but i can't figure out where it leaves the front...

-drew

 

https://mbworld.org/forums/showthrea...21#post2615821

 

Search posts from "GreggC" this will find you the post with all the bosche fuel pump info. It will give you all the bosche part #'s for the replacement and upgraded pumps with all neccesary info.

Also, there is a vent for the tank that needs a vacuum source. We forgot this in the begining and it will trigger a CEL. It's a hard plastic line off the firewall. Make sure it sees vacuum but not boost. Pull vacuum from the TB port pre-blower or use a small check valve hold off boost.

Any idea how your going to run the PCV system?

 

i had found that before but the search was down and i couldn't find the info

my pcv system is done and working for now- currently it's basically as hps described. I will have to see how much oil gets dumped through the charger before i try something else.

are you talking about the hard line at the back of the engine (on the firewall) that stock runs into the back of the upper intake? if i leave that stock/as-is it will see boost... so that's something i need to change now? it didn't throw a cel yet after driving it quite a bit.

-drew

I'll post pictures of all my routing later just for confirmation purposes etc.

 

I never had that line exposed to boost. I had it open to atmosphere once and that triggered the CEL. On my app. that line connects to the TB port pre-blower and sees vacuum only. I would think that boost would upset something being its a vent, or as I was told.

 

interesting...

you mean the hard line goes from the firewall to something you ran to vacuum way up front?

where does the back of the manifold line go (that used to go to that hard plastic line) now?

 

update-

too much snow to test maf stuff out today- but a few options are here.

Gauges are here- digital iat, fuel pressure, boost/vac, and voltage

fuel pump is going to be ordered soon

timing control is going to be added (ftc1-24 or just at the tc1 or whatever they call it- unsure which route yet)

still unsure of whether or not i'll be running fmu with larger pump (or what else will allow me to add fuel over the 5v maf reading...)

oh yeah and i'm 90% about doing an AIR-WATER INTERCOOLER... forget meth! I've got the parts sourced that i believe will fit...

 

have you considered water-methanol injection as one of your "tuning" solutions ???

 

yes, and want to avoid leaning on it as much as possible- i may end up with a little meth (or nitrous is actually more likely if the air-water works as i want) but i'm too worried about the dangers (and disposability) of meth in my situation- driving the car every day etc. (in the summer)

 

i will be running both an air to water system as well as a meth setup. air to water for every day driving, and the meth to kick in only under high boost or high temps or wot not sure of final meth set up.

 

IF the air-water works as well as it should nitrous may be a better option than meth (just a 50-75 shot or so under wot)- it will make a TON of tq too

 

There should be two ports at the back. (1) on the intake mani that was already there, and (1) that is on the HPS supplied elbow that connects where the TB was. One of these ports will be used to supply vacuum to the PCV system with a check valve inline to prevent boosting the crankcase. The port on the HPS pipe I threaded internally for the IAT probe. So those are all used up. To supply vacuum to the tank vent hard line you can run a line up to the TB up front or T into the PCV line with the check vavle.

The two 3/8 ports on the valve covers should go to the vacuum source with the check valve/PCV valve. The large 5/8 port on the drivers side vlave cover I have going to a catch can with a check valve in line.

This way when the car is under vacuum which is most of the time the check valve and PCV valve create a little vacuum for the cranckcase which is good. Because the larger 5/8 line has a check valve going the other direction it keeps the PCV under vacuum. When boost hits the the 3/8 valves close preventing boost into the CC and the larger 5/8 valve is open allowing any blowby and CC pressure to be vented into the can. So under vacuum my PCV functions normally and under boost it is like an open breather system. Its the best solution I could muster up without the use of a vacuum pump. This make any sense????

I actually spent a month trying to fab up a GZmotorsport street pump but could get the room....good luck trying to fit an Air to Water or any type of charge cooler...hell if I drop a wrench I can barely get to it let alone fit a cooling system. I'll send you a rack of beer if you can pull it off!

 

Sitting here a little stunned. HPS is still in business??

Wasnt there basically nuclear war over them on this forum few years ago?



Hope everything works out!!

 

ONce again, check out GregC's setup that he used(or tried) in terms of air cooling. I would have gone the same route and would have thought it would work great. Surprisingly he lost a good amount of boost and power. The IAT's dropped but the relation of power loss to IAT drop was way too much.

He used a small barrel intercooler which fit perfect but was too small, Check it out.