Hey so im building a 3400 for my 86 get and its going to be running 15 psi (turbo)... so far all is going well although one thing that i have no clue about is the fuel. What size injectors/ fuel pump.. management?? (going to be using 7730, if it changes anything).

Any sugestions?

email gmtuners and see if he can give you a base tune using 3800sc file as a starting point with 3400 timing tables. It's worth a shot anyway.

Will you be tuning yourself?

Get a moates ostrich and use code 59. Its a modified/hacked version of $58 from typhoons and cyclones.

There is a whole website dedicated to it: code59.com

For fuel pump use what the 3800 guys here are using.

quote Originally posted by darkhorizon: the TRE pump is GREAT for up to 375whp, and is dead silent. Have ran at least 5 in cars I have built personally and after 3 years of using them I have yet to have a failure. A bosch 044 would be a good upgrade to the TRE pump and provide up to 550-600whp without much issue. It is a bit more than twice as expensive as a TRE pump, but IMO it would be a better option than running 2 pumps.

I'll be getting a TRE

I'd suggest 42 lbs injectors minimum. I'm running 30 lbs injectors on an iron head 3.4L at about 10 psi and must run gas as E85 will go lean.

I also run the 7730 with the $8F code as I could not get code59 to work with DIS properly. Joseph Upson gave me a link to a 3400 running code59 successfully so I am once again thinking of switching. Using code59 allows running up to 30 psi with a 3 bar MAP sensor.

15 psi is an absolute blast but you always want more! (If you plan on more then go right to 60 lbs injectors.)

quote Originally posted by Hudini: I'd suggest 42 lbs injectors minimum. I'm running 30 lbs injectors on an iron head 3.4L at about 10 psi and must run gas as E85 will go lean. I also run the 7730 with the $8F code as I could not get code59 to work with DIS properly. Joseph Upson gave me a link to a 3400 running code59 successfully so I am once again thinking of switching. Using code59 allows running up to 30 psi with a 3 bar MAP sensor. 15 psi is an absolute blast but you always want more! (If you plan on more then go right to 60 lbs injectors.)

I'm using Code59 and it works well. What's really nice about it is that you only need to add a 3 Bar MAP and proper bin mask to get started. No wiring changes if you are running 8F or A1 with a 730 ECM.

[This message has been edited by Joseph Upson (edited 12-07-2010).]

Thanks, I was leaning more towards having someone else do the tuning but we'll see. To be honest I dont even like putting the wiring together but i'll manage.

Will any fmu work as long as it is in the psi range?

[This message has been edited by dutch13 (edited 12-07-2010).]

quote Originally posted by dutch13: Thanks, I was leaning more towards having someone else do the tuning but we'll see. To be honest I dont even like putting the wiring together but i'll manage. Will any fmu work as long as it is in the psi range?

My preceptor was very adamant that I not use acronyms because they can have a different meaning than what was intended to some. I use them in writing but try to spell it out at least once first.

What is an fmu?

quote Originally posted by Hudini: I'd suggest 42 lbs injectors minimum. I'm running 30 lbs injectors on an iron head 3.4L at about 10 psi and must run gas as E85 will go lean.

I hate to tell you but E85 you have to have bigger injectors to get the same effect as say 93. On the gtp forums if someone has 42lb injectors and wants to run E85 they up there injectors to 60lb. But E85 is very close to race gas as far as knock is concerned so that may be why yours runs better!

But on a side not did you change the pistons/headgasket for boost on a 3.4??

FMU = Fuel Management Unit

quote Originally posted by black86v6: I hate to tell you but E85 you have to have bigger injectors to get the same effect as say 93. On the gtp forums if someone has 42lb injectors and wants to run E85 they up there injectors to 60lb. But E85 is very close to race gas as far as knock is concerned so that may be why yours runs better! But on a side not did you change the pistons/headgasket for boost on a 3.4?? FMU = Fuel Management Unit

Thanks for the descrip. I believe he's saying the same thing except in a different way. E85 requires larger injectors otherwise fuel flow will not be enough under the same circumstances as with a calibration for gas therefore causing a lean situation. He uses gas.

ahh ok, mybad, I read that wrong.

quote Originally posted by dutch13: Will any fmu work as long as it is in the psi range?

An FMU is not needed. You will be taking care of fueling issues with the bigger injectors, proper fuel pump, and proper tuning on the 7730. Add a wide band O2 sensor and knock sensor and you can manage your engine without it.

I agree about (I hope you "BUILT" the bottom end to take the boost) better rod bearings & mains, head gaskets... ect

yes ofcourse. Bottom end redone. arp. lower compression forged pistons, heads, head gasket. arp top.... cam. the whole nine yards. Thanks for the help guys. Appart from that i'll definitly look into the whole tuning myself, just dont want to risk ruining anything.