cold and hot fuel pressures

[jbrown]

I had new fuel pump and cams installed and have to do some fine tuning on the WUR.. Does anyone no what the my cold pressure should be and what my warm pressure should be.. I have a CIS gauge hooked up and I forgot what the pressures were suppose to be....
Thanks John

[jbrown]

My cold pressure is at 2.2 and my warm pressure is at 3.7 . Is that about right?

[jbrown]

I am running pig rich with the meth injection and a 044 fuel pump up front... I have an adjustable warm up regulator and the solinoid. I am running rich in the mid range even with the solinoid set to 5400 rpms. I am at 10.8- 11.1. Can I adjust the WUR to control the midrange? or is there another way to get the A/F leaner in the mid range...
Thanks John

[jbrown]

I am sorry I am getting those A/F reading all the way to 6500 not just midrange...

[RarlyL8]

Optimal pressures depend on your mods/HP. List your mods and I can give you the pressure targets. Need this information:
> System Pressure and Flow Volume
> Fuel Head Type (US/Euro, stock/modded)
> Wheel HP @ what rpm, dyno graph is optimal

[jbrown]

I will have to check tommorrow on the system pressure. I know it was set to what ever Brian recommended when I put in the WUR.

I did a Flow volume test about a yr or so ago and I know it was right on stock specs for flow rate.

The fuel head is a US modded by Imagine Auto when they were around.

It hard to give you HP. I do have an old dyno sheet . It made 341rwhp and 363.1ft-lbs at 5298 rpms. I have done alot of changes since then. The motor is similiar thou....
It is a 3.5 liter built on a 3.0 block. 8.1 compression, K27hf turbo,BandB exhaust,XDI crank fire ignition, garretson intercooler,modded fuel head, adjustable WUR, 964 cams, solinoid to hold out inrichment, Snow Per meth injection, short bellhousing 4 speed, rebuilt with shorter gears, 13lbs boost. Thats what I can remember at the moment...

I had great A/Fs before I put in the cams, I went from sc to 964 and I changed the front fuel pump to a 044. Thats the only two things I did.
Thanks John

[RarlyL8]

The fuel head is a US modded

I assume BL was aware of this and compensated.

I don't see headers on your build list, do you have them? What was peak WHP (~6500rpm)? You should be hitting ~380WHP with that setup and headers.
The 964 cams will shift the power band slightly to the right.
Have you tested fuel flow and system pressure with the 044 fuel pump installed?

[JBL930]

With a modded fuel head and that boost level why do you have meth injection?
The solenoid is only there to delay fuel when you are on boost, it has nothing to do with your midrange cruising AFR. 5400 rpm is late for boost enrichment, be sure you are not going lean after 4000 rpm at WOT.

Be sure to have power going to your WUR for at least 5 minutes to make sure it's warmed up before you adjust the warm/cruise control pressure.

[jbrown]

I do have headers, B and B. The dyno numbers I gave you were from my motor before I had it rebuilt. It was a similar motor though. Same displacement and set up except I had sc cams at the time and it was only running .7 bar boost...

Let me try to exsplain this again.. The car ran fine. Cold start fine , warm start fine. A/F were good but when I was runnning the car with 13lbs of boost I would run upwards of 12.7- 12.9 at about 6500 rpms. So thats when I put in the meth injection and that cured the problem. At 6500rpms my A/F with the meth were 11.5 at 6500.

I was running the motor for about 3 yrs no problems with anything. Recently I had a minor tapping coming from the valves. It was a pitting cam lobe. So i decided to have it replaced but instead of putting in sc cams again, I went with 964 cams.

When the cams were installed I had a new front fuel pump installed (o44). Since I have made those two changes I am seeing richer conditions. I am assuming the fuel pump is causing the richer condition.

I have an innovative wide band in the car. I have my A/F at idle at 14.0-14.5. The car starts fine cold and hot. Under cruise it is fine. If I get on it and go to 6500rpms I am at about 10.8-11.2 from 4500 to 6500. So basically I am trying to lean it out alittle.

I no what the solinoid is for. I had it originally set at 5000rpms before I installed the cams and fuel pump and it was PERFECT, I was at low 12's untill 5000 rpms then when the solinoid opened up I dropped down to 11.5 to redline. So I was just thinking maybe I have to adjust my cold or warm pressures to change the midrange A/F.

[jbrown]

The meth injection I have in there to help the motor from detonation because it is a 3.5 with 8to1 comp and I wanted to run more boost. I could always go up more boost to lean it out alittle but I dont want to run more than 13lbs.. It also changes the octane to 110 ( when the meth is on) and my motor is only single plug.

[JBL930]

You should be able to get that right with simply adjusting the WUR, If your cruise AFR's are all good, then just adjusting full throttle enrichment should be simple. Have you run out of adjustment at the WUR? If so then your only option may be to lower system pressure and adjust all parameters to suit. Or change your fuel head for a standard one?
Sounds like your idle AFR's are a bit lean, thought they should be in the mid 12's?

[jbrown]

I can adjust the idle A/F. I thought it should be at 14.0. No I have not played with the WUR yet. I will adjust full throttle enrichment. It is going to be raining here for the next couple of days so I will have to wait.

[RarlyL8]

Yes the MeOH injection is a separate deal to combat detonation due to high CR combined with high boost pressure and needs to be functioning when you adust boost AFRs.
The 044 pump has a higher output than the old OEM front pump and has changed the baseline that your WUR settings were derived from (you know this). There are a couple of ways to correct this; turn the fuel head back down to factory specs and/or re-tune the WUR.
Turning the fuel head down will result in better fuel mileage than adjusting for the increased flow via the WUR. If you wish to go that route but don't want to do it yourself I have a fuel head in stock to swap or can adjust yours. System pressure needs to be verified first though.

[JFairman]

Usa a small C Clamp to press the dime sized disc on the bottom of the B.L. adjustable WUR inwards.
That will raise the boost control pressure and lean out the boosted AFR.
I would guess you'll be pressing in that disc around .020" or maybe a little more and you should have the tool Brian Leask includes to pull it back out if you go to far.
You can remove it, turn it upside down and tap it in with a hammer and brass drift too but the shock and vibration form doing that isn't good for the internals and you can do it with the C clamp without removing it from the car - just remove the two 10mm nuts and wavy washers and slide it up off the mounting studs with the rubber fuel lines still attached.

I've got a similar setup with a CIS flowtech 20% over modified fuel head and high pressure WMI, 964 cams and B&B headers but only 3.3 liters. I've tried water only and that actually leans the motor out a little when spraying but does cool the intake manifold and intake air alot and steam cleans the combustion chambers to some extent while raising the detonation threshold.
I've also tried around 40% methanol mixed with the water and that richens the AFR's while spraying.
I can turn my water injection on manualy during steady cruise to feel if it's working and see the AFR changes and after about 2 seconds the motor will start to missfire when doing that during steady cruise. Anotherwords if you're still too rich during boost while WMI is spraying you can try less methanol in the water mix and your AFR's will be less rich and you'll still get the benefits of water injection.

I'm using the M5 WMI nozzle from cooling mist that is for a motor between 300-500 horsepower and the smooth running adjustable 200-250 psi recirculating type diaphram WMI pump currently set to turn on at .8 bar and pump the water at the default 200psi.

Maximum boost I see with the K27 7006 turbo is currently set at 1.15 bar with a manual boost controller in the wastegate line. I'd try higher boost but still have regular dilivar headstuds torqued to 25 footpounds and people say you shouldn't push them higher than 1.1bar or the heads lift.
We have 93 pump octane and no emission inspections here in Florida... but the roads are flat straight and boring. The women sure aren't though.

[jbrown]

First I want to thank you guys for the help. I am hoping I can adjust this thru the WUR.
I have the disc all the way out for enrichment. I have not had a chance to tap it back in to lean out the full enrichment. I am going to do that next nice day..

The other thing I did not think of is the ratio of meth to water. I had about a 50/50 mix and my A/F at boost was alittle leaner. The day I took it for a real test ride , I added some straight meth to the tank to boost up the meth ratio and I did not even think it would make my A/Fs richer. Thanks JFairman. You learn something new everday,lol.

The other thing is , I thought with the solinoid the in the system to hold off enrichment, that were the disc is in the WUR does not come into play untill the soliniod opens and lets it inrich.
Am I wrong? I hope so because that should solve my problem as well as seeing what meth to water ratio is best for my set up...

[JFairman]

I've spent alot of time repeatedly adjusting my Brian leask adjustable WUR... maybe more than anybody and now it works as perfectly as modifed CIS can.

With the disc out all the way and a 20% over cis flowtech modifed fuel head you will be too rich under boost with no control over it no matter what you do.
You have a lot of trial and error tuning to do so be patient.

I have the CIS system and control pressure gauge but I never use it when tuning boost, cold start, idle, or warm steady cruise AFR adjustments so I don't know what those control pressures are and don't care because it runs as perfect as modified CIS can.
I watch the wideband analog G3 AFR gauge (when it works) for that when tuning.

That said, I have checked and written down my constant system pressure which is 97psi and cold start control pressure at a certain ambient temperature for reference.
AFR's are around 10:1 at cold start depending on ambient temperature and it starts and idles smooth perfectly with no smoke or over rich AFR stink, around 13.5 to 14:1 at warm stable idle depending on it's mood, around 14.8- 15.2:1 warm steady cruise depending on speed and what mood CIS is in for best possible gas mileage on flat S. Florida roads, and right around 12:1 at 6500rpms under 1.1bar boost.
I have the vacuum solenoid and digital rpm switch installed to block the boost enrichment signal to the WUR until 4600rpms when it opens.

I say what mood the CIS is in because once you modify the fuel head for more fuel flow and remove the lambda system the AFR's will never be perfectly consistant all the time, but they will be close and it will run fine and AFR will stabilize back to the same places after 5-15 minutes of driving depending on ambient temperatures, the WUR bimetallic spring temperature, and cylinder head combustion chamber temperature.