is it ok to run15 psi?

[7m4runner]

My current mods are
3" turboback exhaust
slightly upgraded ct26,
walbro fuel pump
wideband o2

I hit fuel cut at 11 psi, If I were to purchase a FCD would it be ok to run 15psi. on stock injectors and stock fpr? Im just wanting to squeeze out a little more power without spending a lot of money:naughty:


Oh yea i did MHG and Arp's too

 

[supraguy@aol]

My current mods are
3" turboback exhaust
slightly upgraded ct26,
walbro fuel pump
wideband o2

I hit fuel cut at 11 psi, If I were to purchase a FCD would it be ok to run 15psi. on stock injectors and stock fpr? Im just wanting to squeeze out a little more power without spending a lot of money:naughty:


Oh yea i did MHG and Arp's too

You can go as high as 15 psi, but most people say that the CT26 runs out of efficiency range around 12-15psi. That being said, I run mine at a max of 13psi, but I do have a Walbro an AFPR, and a MAFT. Without at least an AFPR, I would be concerned with trying to ensure that the A/F ratio was safe at all rpm's.
Hope that helps.

 

[7Mboost]

You may need those fuel upgrades depending on what you mean by slightly upgraded ct, what is it?

 

[GrimJack]

Cripes... another one of these threads.

Essentially, no, it's not safe. You need to put it on a dyno and listen with a set of electric ears for knock in order to determine safe boost levels.

Anyone telling you PSI levels that they consider 'safe' is guessing.

 

[supraguy@aol]

And yes, I am guessing, I know.
I agree that a dyno tune is the only way to know if the boost level is safe.

 

[CajunKenny]

Remember! Fuel cut is your friend! It helps prevent detonation and running a cylinder lean. Remove it without proper mods is begging for Detonation which equals BHG! And among other bad possibilities!

I know this is echo'd in about every one of these threads; but, here goes... Do it right!

Cheap power will cost you BIG in the end.

We're not trying to step on your fruit loops, we're just trying to prevent another BHG thread!

 

[supraguy@aol]

LOL!!...step on your fruit loops....good stuff.

 

[CajunKenny]

That's cajun talk brutha!!

 

[supraguy@aol]

Shoulda been pork rinds then.
:naughty:

 

[enjoi.this]

Its always good to do it right so it lasts

 

[92TealSupra]

I do believe the math has been done already about the efficiency of a ct-26. it really is not a large turbo that is made for much over factory boost, that is why i.e they sell after market turbos, also tuning by far is more important then adding huge turbo's, fuel injectors, fuel pump. That pump you have doesn't do anything for you right now. You would need a FPR, a tuning device ( cheap one being a Apex-i ) there are many others, including AEM EMS, MOTEC, and plenty more. I do not think buying a FCD is the best choice but again your car is yours and I can only state my opinion. if I were you I would at least* get a Apex-i NEO, a lexus AFM which raises all the parameters 25% which can also help you, 550cc Injectors and a Aeromotive Fuel pressure regulator, and a upgraded turbo, easiest for you may be a ct-26 57, 60, and 62 trim. I ran a 12.9 with 16 psi out of a 62 with a tuning computer 550's and a FPR, anyhow good luck.

 

[Yblegal91t]

if you want a little more power without having to trick your computer, then just get an electronic exhaust cutout, or a nice CAI. it will run about the same price as teh FCD. and clean your 440's

 

[Poodles]

IIRC the FCD clamps the AFM signal... yeah, not a good thing.

It's meant to be used with the full suite of HKS electronics as a system, not by itself.

 

[Fubar231]

Don't cheap out with a FCD. All they do is prevent the engine, and running over Fuel Cut make the car run lean. The higher the boost the worst it is. FCD Is BAD.

 

[7m4runner]

well i'm not trying to beat a dead horse or argue my reasoning
but im just curious...since I shouldnt be pushing more that 440 hp with a 50 trim I dont see the need for 550 injectors, and since all a lex afm does is raise the fuel cut anyway, shoudnt I just be ok to sun 15 psi if I add an AFPR and a FCD.

oh yea in case it matters I also have a CAI and BOV

 

[IJ.]

Is this in a Supra or a 4runner?

 

[7m4runner]

IIRC the FCD clamps the AFM signal... yeah, not a good thing.

It's meant to be used with the full suite of HKS electronics as a system, not by itself.

how is tricking the computer to run more boost different that tricking the computer to let more air in with a LEX afm

 

[7m4runner]

Is this in a Supra or a 4runner?

86 toyota 4runner with an 87 7mgte

 

[IJ.]

Vehicle dynamics change everything, unless someone here has run your particular combination it's only guess work and opinion.

I think you'll have to be the trail blazer on this one, maybe buy a knock link and see what you can get away with.

 

[Poodles]

how is tricking the computer to run more boost different that tricking the computer to let more air in with a LEX afm

Because the lex AFM is meant to be used with the 550 injectors , you're just moving the entire map over a bit.

Completely different ideas, and the FCD is NEVER to be used by itself. HKS even stated this in the article I read (it's posted somewhere) about when they first tuned the MKIII supra.