I'm more thinking an upgraded (adjustable) regulator, as opposed to a pump... as the pump is more powerful than the stock regulator allows passage through. I'll have to check the flow rates when I get closer to purchasing injectors. As I said, the first route I'm taking is to send the ECU back to powerchipgroup to see if they can fix whatever it is first. Still waiting for a reply. I'm working nights this week so it gets harder to collaborate phone call convo's during business hours. :\

 

I agree...an AFPR would be nice also, but a pusher pump would be a good buffer.

Do these cars have returnless fuel lines, or is there a return line? I'm not familiar with them at all.

SQ

 

From the projects I've undertaken and my recent adventures with my car... it may surprise you to know I'm somewhat of a newbie at a lot of aspects of cars. The first engine I ever rebuilt was this one, people said I was crazy but I pulled it off!

With that in mind, I'm not sure what you mean by return line. These are just pressurized fuel rails, one input, only outputs are the injectors, and then the pressure release at the end that you have to depress before removing the fuel line. This answer your question?

 

Good deal! Glad you cracked right into it and figured it out. If you ever attempt to work on an old 302 or 350, you'll be WELL ahead of the game.

Some cars have a fuel line that returns back to the tank. So, you can push as much fuel as you want to the injectors, and the car will only use what it needs. The rest goes back to the tank.

SQ

 

its a dead head system ... no return lines. Kleeman claims the pump is good to double the stock standard Xf's rating (400 ft/lb) so the srt pump is not straining ...

i suggest against a rising rate fuel pressure regulator as volume goes down with increased pressure ... so you are fixing the problem of the injectors running out of pulsewidth and introducing a new one of lower the volume the fuel pump can dish out...

i also suggest against larger injectors cause you will be taking drivability away from the car as factory cold start settings and the like will not be supply the same flow of fuel at a particular pulsewidth as it thinks it is ... remapping the ECU for the new injectors is a wasteful pursuit at best due to the money involved...

my suggestion ? auxillary injector ... a extra 90 lb injector and holder can be placed at after the supercharger and before the throttle body ... auxillary injector driver (your choice, emanage, megasquirt, whatever) can be programmed to spray at MAP values beyond the stock systems capabilities ... the schrader valve on the fuel rails can be utilized as a nice neat 4AN fuel port for the injector. its clean, its reliable, its cheap ...

 

How can the injector be after the supercharger, and before the throttle body...if the throttle body is before the supercharger?

I agree...fpr's are usually a band-aid for a lack of fuel.

SQ

 

clip on the G-tec and post some numbers, I wonder what your 1/4 mile time is?

 

Awesome info about the pump, that saves me a lot of headache.

The problem is, I've already had the ECU mapped once for the 25% overdrive pulley, and it's still not enough fuel. AND on my Apexi I turned the correction all the way up and the fuel is just not there. That's why I'm going for larger injectors. I'm giving the ECU one more chance, and I'm waiting on it's return from powerchipgroup right now. This will be the third attempt. I sent AFR printouts so they can tune around it, but if they CAN'T then larger injectors would be the way to go, and I won't increase them enough to take away driveability. And I have a plan around remapping the ECU around the injectors. I plan on changing to a 2 bar MAP sensor then using my Apexi to set what ratio the injectors are to the MAP voltage. If I keep the ratio linear to the factory settings then the ECU will not need to be remapped, and any small corrections that may not be accounted for I can correct with the Apexi.

I have thought about the secondary injector idea, and even where I'd put it. If I went that route I'd tap into each of the intake manifolds, one on each side. And then I'd simply use the same kind of progressive controller my methanol injection uses. I can set a min and max MAP pressure that it kicks on at and ramps up to until it hits max duty cycle.

But since I can get larger injectors for right around $500, I think I'd rather do that than try to band-aid fix it.

 

I spoke with Erick at LETMotorsports.com , and brought up your car.

He has a 185mm pulley, and said with his headers (on a C32), he is experiencing a lack of fuel at the redline - and therefore the car is pulling timing and 'fixing' this.

He said that the injectors (as far as he knows) and the pump are well up to the task of providing the fuel - he said the MAP sensor is the weak spot.

You may benefit from calling him - he said he had seen your header design, and hadn't seen your pulley - but seemed interested. A good tech discussion may benefit BOTH of you.

Keep us posted!

SQ

 

Excellent info! I will definitely get them to tune if powerchipgroup falls through. I think I will still go with larger injectors if the weak spot is the MAP sensor. This way I can upgrade the MAP sensor and keep the fuel linear. I might try it without, but I'm worried about running too lean when a stock MAP voltage would be (for example, rough figures only) ~ 4.5 v at roughly 20 psi and a 2 bar sensor would display just over ~ 3v then the ECU (thinking the stock MAP sensor is in place) will think a lot less air is moving through and output less fuel through the injectors. However upgraded injectors would get by this. More fuel would still be added due to the larger injectors despite the lower MAP voltage.

Your input has been great, I think I'll have a lot of trial and error on my hands in the next month or so. I'm pretty confident I can get it working though, since I have much control over my MAP sensor voltage outputs with this Apexi tuner. I really think 2 bar MAP sensor and upgraded injectors will do the trick.

 

Long story short... LET/Evotech it is. (sigh) The guys at powerchip don't really know anything about tuning these short of what they have pre-flashable software for.

 

Did you contact Erick?

 

Left him a message.

 

This would spray fuel like a TBI setup before the injectors in you SFI setup. Fuel on top of fuel. Oil and tire companies will love you!!!

 

I have the 185mm Pulley on order with LET and have been told it will ship next week. I had planned on using a local euro tuner who uses a Clayton dynometer for performance tuning.

I don't have a datalogger to record and provide results when shipping my ECU for a remote tune so I will be interested to see how LET/Evotech tune works out for you.

Good Luck.

 

Brian be smart about this investment I have read too many times about tunes not working out or worse paying for them and feeling or seeing no gain inmotion being one of them on the mb forums. Erik has worked hand in hand with evotech to create an ecu to work with the largest pulley on the market. There was a price going around for $995 maybe he will hook you up. It may seem like a lot but your still $1,000 under renntech and going to gain more hp.

 

Last time I checked with Erick they are still working on figuring out the fueling shortage with the 185 pulley.

 

I hear ya - but most members on this and other forums have pulled and shipped their ECU to be flashed - perhaps getting a "out-of-the-box" tune?

LET would be my first choice for the tune (I purchased everything else from them in one bundle) - but I have no way to to test or measure the results without going back to a dyno shop each time anyway, so we would just be flying blind and going by feel or I'll paying extra to for a dyno session.

Having my car on a dyno and performing real-time readings and adjustments would be worth the extra $$ to me.

 

There was a company way back who did an ecu tune as well take it to the dyno and work from there... I can not remember the name I think they later on got blasted for being street racers or something I will try searching also maybe HDDP is reading he was going to put there banner in his garage something I don't remember it was awhile ago but they ended up getting 21 horse out of a stock crossfire, They went tune dyno tune, dyno, tune, dyno. Someone on here got it for free I don't remember the name though.

 

AMGrasoul,

Any updates?

Also - TTT for the guys talking about 185mm pulley