The FMU tuning is coming along great. Still tweaking. I'll post some stuff when I get it totally completed and dialed in. I came up with a pretty cool invention to make the signal supply to the FMU adjustable in different pressure zones which removes the original design limitations. The butt dyno approves.
As far as the larger 80mm MAF I was able to pick up better than 2 PSI. I'm not so much about the maximum boost numbers, more about the extra grunt down low that feels great.
As for fuel pressure I've made significant strides. I'm estimating fuel pressure was 120 PSI with the factory 19lb injectors. Thats just how FMU's work. I can only estimate because my guage stops at 100..... it would go out of limits around 5 psi of boost....That's what prompted the calibrated MAF and 24lb injectors.
With the 24 lb injectors I was able to reduce fuel pressure to 90 psi with the standard operating FMU and a custom made calibration set.
With my FMU invention I was able to keep a nice steady AFR and maintain 11.5:1 AFR (or whatever I want it to be) at maximum boost with fuel pressure ceiling of 65 psi. So I've managed to shave off an estimated 55 psi from where I started. Which is significant.
This got me wondering if I really need the T-Rex fuel pump? So I temporarily bypassed it and took it out for a few runs. I had no problem keeping it as rich as I wanted at max boost with out the TRex. I'll give it a few more runs, but I don't think I need it. The Walbro 255lph HP pumps seems to be fine alone.
When I installed the TRex it calls to cut the factory fuel line (tank to filter) and re use the fitting. So I need to replace the line. I found one at at a company called Classic Tube that makes all sorts of fuel and brakes lines for our cars in the USA. Pretty neat it's just around the corner from me.
As far as the larger 80mm MAF I was able to pick up better than 2 PSI. I'm not so much about the maximum boost numbers, more about the extra grunt down low that feels great.
As for fuel pressure I've made significant strides. I'm estimating fuel pressure was 120 PSI with the factory 19lb injectors. Thats just how FMU's work. I can only estimate because my guage stops at 100..... it would go out of limits around 5 psi of boost....That's what prompted the calibrated MAF and 24lb injectors.
With the 24 lb injectors I was able to reduce fuel pressure to 90 psi with the standard operating FMU and a custom made calibration set.
With my FMU invention I was able to keep a nice steady AFR and maintain 11.5:1 AFR (or whatever I want it to be) at maximum boost with fuel pressure ceiling of 65 psi. So I've managed to shave off an estimated 55 psi from where I started. Which is significant.
This got me wondering if I really need the T-Rex fuel pump? So I temporarily bypassed it and took it out for a few runs. I had no problem keeping it as rich as I wanted at max boost with out the TRex. I'll give it a few more runs, but I don't think I need it. The Walbro 255lph HP pumps seems to be fine alone.
When I installed the TRex it calls to cut the factory fuel line (tank to filter) and re use the fitting. So I need to replace the line. I found one at at a company called Classic Tube that makes all sorts of fuel and brakes lines for our cars in the USA. Pretty neat it's just around the corner from me.
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