fuel cut?
- Thread starter Supraguy7M
- Start date
Supraguy7M;1931335 said:
I kinda skimmed through all the thread... isn't the simple answer... "you wont hit fuel cut". Period?
A 60-1 CT 26 will be able to do 14-18 psi, however (and this is my opinion from having exactly that... a 60-1 with 550 injectors and a Lex AFM) your going to be putting a lot of load on a turbo without really accomplishing much because the housing is to restrictive. I am not topping 14 psi on my 60-1 simply because from my understanding, (and this is going by flow) the turbo will Spool up nice and hard, but then it will be maxed out trying to get more air through the small housing. I am not sure how much of what I just said is true, but I chose to just get a nice pull and keep the turbo alive by not overboosting too much. Its still fun, however, I personally decided to go to a T4 newer turbo in the future to allow for proper flow. I can live with how the car presently drives until then. (of course at that time I will also be going with a full stand alone system)
You don't need anything with a 550/lex afm/60-1 CT26. That setup is safe to run and its very unlikely you will lean out and cause any issue if your engine is in good condition. Wideband is helpful to let you know you aren't leaning out and an AFPR is useful to limit fuel slightly if your running overly rich with the larger injectors. If you haven't upgraded your fuel pump (which you shouldn't need to do with this setup), you shouldn't have to worry about that either. The stock fuel pump is fine to feed 550's.
From what I understand, the only thing you need to really let a MK3 run nicely is 3" turbo back exhaust (stock elbow is restrictive), 550 cc injectors, lexus afm. That with even a stock CT26 will give you a helluva different feel on the car. Upgrading the turbo to a CT26 variant is fine but you will still run off wastegate pressure without a boost controller (you never listed your other mods that I noticed). Mine was holding until 10 psi. (with a 57 trim, stock intercooler, boost controller disabled) It was a good pull at 10... 14 was very nice. I never went higher (with boost controller setup) because I couldn't keep the tires from spinning in 1st/2nd.
^ my mods are Godspeed fmic kit, greddy turbo timer, greddy profec b spec 2 boost controller, 3in turbo back, 60 trim, bc stage 2 cams, minor port and polish, 10mm plug wires, arp studs, hks mhg, lex afm, all new hoses, hks ssqbov, obx cam gears (hate them!), gates timing belt, aem wideband that's it at the moment. No where near done though. Bottom end was good so I'm leaving it until this coming winter, when I pull the motor and FULLY build my 7m
Yeah, your not gonna have to worry about fuel cut... lol. And why would you need to fully build? Sounds like you have a solid engine already (if its done right with those parts).
I wouldn't touch it unless it was having issues or your shooting for something over the 600 HP mark.
I wouldn't touch it unless it was having issues or your shooting for something over the 600 HP mark.
you don't NEED an afc but it does help
you can the longer adjustment screw for the afm to adjust it that way(someone on here will know what it's called)
but you will need an afpr and fuel pump(may be wrong about fuel pump someone correct me if I am)
you can the longer adjustment screw for the afm to adjust it that way(someone on here will know what it's called)
but you will need an afpr and fuel pump(may be wrong about fuel pump someone correct me if I am)
No, all you need is the Lexus AFM and the 550's. the AFPR is mostly for if you get a fuel pump with more flow. Personally I wouldn't touch a FCD because it takes away the computers ability to protect you from running lean.
According to Reg Reimer you don't need a bigger fuel pump with 550's either.
The wideband is only useful in letting you know that your not leaning out. With your build you should be fine.
According to Reg Reimer you don't need a bigger fuel pump with 550's either.
The wideband is only useful in letting you know that your not leaning out. With your build you should be fine.
well a 20 year old car suddenly using it's fuel pump at full capacity ALOT more, won't take long it burn it out. So fuel pumps are more of a reliability thing. I know I don't feel safe running 16 lbs of boost until I put my new pump in.
Yeah that's what I thought but I had to turn my fuel pump down to 25 psi at the AFPR to prevent it from going so rich it was washing oil off the cylinder walls at WOT.
Have to look at what duty cycle a 550 cc injector is doing at less than 400 rwhp. ( not an expert, so I could be wrong, however from my car, I didn't need the fuel pump upgrade yet.)
Have to look at what duty cycle a 550 cc injector is doing at less than 400 rwhp. ( not an expert, so I could be wrong, however from my car, I didn't need the fuel pump upgrade yet.)
Grandavi;1932086 said:
cylinders are still crosshatched, no ring step, nothing. Bottom half looks about brand new (not even carbon on the pistons) at 150xxx.
That's the only reason I have done only top end work and just lower gaskets. I wanna build the car to to about 600-700hp on the 7m. So that's why I plan on pulling it and doing the bottom end at the end of the year. Those are future plans though. Oh and I forgot one mod, my Walboro 255
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The fuel pump is an easy job, just remember to lower the gas tank a bit to do it.
If your engine is as sound as you describe with a properly prepped and torqued MHG and OEM pistons your good to about 600 Hp at the crank. People tend to underestimate the 7M because so many are done poorly and then hammered to the point of failure. My 7m is built (rebuilt because of crappy build by previous owner) for 700 hp with plans of climbing as close to 500 as I can get it on 550 injectors. Anything over 400 at the wheels will make me happy.
If your engine is as sound as you describe with a properly prepped and torqued MHG and OEM pistons your good to about 600 Hp at the crank. People tend to underestimate the 7M because so many are done poorly and then hammered to the point of failure. My 7m is built (rebuilt because of crappy build by previous owner) for 700 hp with plans of climbing as close to 500 as I can get it on 550 injectors. Anything over 400 at the wheels will make me happy.
