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General Category => Intros - 3500 HD History => Off Topic Items-Politics-Jokes etc => Topic started by: ED-NY on January 04, 2018, 08:13:08 AM

Title: TBI tuning option!
Post by: ED-NY on January 04, 2018, 08:13:08 AM
Check these out:

https://www.ebay.com/itm/Injector-Tuner-for-EFI-Optimum-EFI-TBI-Throttle-Body-Injection/252865497725?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D47301%26meid%3D61e015035b5a4a82ae22dd64f59c2839%26pid%3D100623%26rk%3D2%26rkt%3D6%26mehot%3Dpp%26sd%3D252871869017&_trksid=p2047675.c100623.m-1


https://www.ebay.com/itm/Injector-Tuner-w-regulator-for-EFI-Optimum-EFI-TBI-Throttle-Body-Injection-/252871869017?afsrc=1&rmvSB=true
Title: Re: TBI tuning option!
Post by: MrC. on January 04, 2018, 01:56:25 PM
Hey Ed.

I'm glad you posted this.

I have been reading we (3500hd's) have a higher pressure regulator factory. I have read it is 30 psi as opposed to the 13-15 psi of a half ton truck. I have also read we have small stock injectors 42#. I have been thinking about replacing my stock injectors with 55-60# units. and adding a chip (maybe a custom one) along with free flowing exhaust (no cats).
Would you see a power gain in this setup of am I missing something?

I had a 95 tbi 1/2 ton w/ 305 back in 96, I changed out to larger Holley injectors, and raised the stock pressure to 20 psi, along with a chip and underdrive pulleys and exhaust, it was noticeable. and smoked stock 350's of the day. I was hoping to repeat those results with my 3500hd.

Any advice?

Thanks,
MrC.
Title: Re: TBI tuning option!
Post by: ED-NY on January 04, 2018, 06:14:59 PM
Don't remember which engine you have but fuel alone won't make a huge difference. As you know, heads, cam and exhaust need to be included in a performance upgrade.  I have had luck un-soldering the proms in 1227747 ECM and soldering in a zif socket so we could use a flashable prom.

What I did with my current 3500HD is install a TPI setup and wired in a TPI ecm to run it. Did not put it on the road yet, it's done but I don't want to drive it in the Winter.  The truck is parked outside and has been sitting for a couple of months....this AM it fired right up. I'll know in Spring how it works, the TPI engines are noted for low end torque.
Title: Re: TBI tuning option!
Post by: someotherguy on January 05, 2018, 09:01:26 AM
I have been reading we (3500hd's) have a higher pressure regulator factory. I have read it is 30 psi as opposed to the 13-15 psi of a half ton truck. I have also read we have small stock injectors 42#
It's not a 3500HD thing.  The 1994-1995 7.4 engine has a higher pressure pump and different injectors than the earlier years, even in the 3500 and 2500 trucks.

Richard
Title: Re: TBI tuning option!
Post by: MrC. on January 05, 2018, 03:14:46 PM
You are right Someotherguy, I did read that only 94-95 3500HD's had the high pressure pump. Thanks for stating that.

I have a 1994 3500hd. I have not checked the pressure, but from what I have read it should be 30psi with 42# injectors.
That said, would there be any gains if I switched to a 50-60# injectors and removed the cat and opened up the exhaust?

Thanks
MrC.