Modifying GM TBI Fuel Injection - Part II

After re-installing my rebuilt and modified throttle body, I went on to install a Jegs' Off-road Y-pipe and tuned the adjustable fuel pressure regulator. The rest of the exhaust is a Flowmaster 50-series cat-back system.

[@FuelInjectionSucks]

The TBI rebuild kit was from Autozone. Regulator was from CFM technologies. Y-pipe from Jegs.

[@FuelInjectionSucks]

Huge increase in power, but I can't narrow down what gave the power. I think it was mostly removing the cat and the fuel pressure. Jury's still out on the TBI spacer.

[@npsit1]

@2:59 My 92 suburban has a advance disconnect next to that wiring block (under that plastic cover beside the a/c) on the passenger side in the engine compartment. It's a lot easier than going under your dash. Not sure if yours has that.

[@FuelInjectionSucks]

+npsit1 Nope, in 1994 they moved it under the dash.

[@hoofarted8709]

that's because on 93-95 the timeing advance for the ecu is located under glove box...

[@limabravo6065]

Affordable fuel injection just released their tbi injector tree the ditches the pod injectors for high impedance modern fuel injectors

[@turdferguson7270]

I always shoved 9°-10° at them, zero was for emissions. Wakes them up and didn't even ping pulling an old heavy 28' enclosed loaded for the swap meet. Last cheap and reliable system gm used.

[@jeepguy4ever30]

Did you notice a difference with the tbi spacer? I recommend advancing the timing 3 degrees over stock and run 89 octane (plus) fuel. It will give you a couple extra ponies. I felt a difference. Any more than that and you will have problems with pinging.

[@FuelInjectionSucks]

Not sure of a baseline, since I didn't have a test port. It's happy right now at about 13 PSI, any more and it runs rough cold and leaves soot on the rear quarter.

[@danielmillard8134]

mate u didn't flip the lid trick on the air clear box! lol.

[@jeepguy4ever30]

Check out the engine masters air cleaner shootout. It DOES make a difference in HP on the engine dyno!

[@heffedirte6243]

Sucks hot air....lmao

[@aps454]

If you are using the stock filter housing get a Jegs # 50080. Don't laugh it works. Just be sure to cut the bottom of the housing to the right diameter for the new spacer.

[@domivilanuevav9474]

So the shiny intake manifold is the Edelbrock tbi manifold not not

[@thedobermangang3503]

THE UPGRADES YOU DID .......DID YOU HAVE TO ANYTHING WITH YOUR CHIP

[@WinXpert12]

I dont think people remove the Cat for more HP, I personally remove them once they fail for beter mpg. Its been proven time and time again that the Cat's reduce your mpg.

[@cameronc.7885]

I had the same issue with mine stripping when i built a motor for my z71 i had the 670cfm tb for mine

[@thedobermangang3503]

IS THAT A STOCK INTAKE YOU HAVE ON THERE ...AND WHAT SIZE FUEL REGULATOR ADAPTER YOU GOT HOOKING UP YOUR GAUGE THEY GOT TWO SIZES 7/16 AND 1/2 INCH

[@kobeebeatty2965]

Haha.. i like the way you weld. Gloves are refered to as bitch mittens. And im digging all your advice. Planning on rebuilding the tb on my 95. Getting the edelbrock performer plus part # 3072 cam and lifters. made for tbi trucks. Im excited

[@Levisnteeshirt1]

the better Y pipe prolly helped a ton

[@deanobabino833]

Great videos on the rebuild and the install! How does it all perform? I am planning on doing these mods, but am still doing my homework on the proven benefits....

[@jaimetale7743]

Would installing bigger/aftermarket injectors be good or bad?

[@IcelanderUSer]

After the fuel is sprayed into those two cups does it just run down a hose to the cylinders? I don’t understand how the fuel is pressurized after the spray. Does it just get atomized and enter the cylinder with the air flow? Are you familiar with the Holley kits that let you switch to efi from the tbi or carb? I wonder what the benefits are?

[@FuelInjectionSucks]

Those cups contain two injectors, which spray right at the throttle blades. The Holley kits are still technically TBI, since the injectors are housed in the throttle body. Advantage over factory TBI would really only be power. Advantages over carb would be MPG and drivability.

[@blackbeardSCBC]

Do you have a part number or link for the Orings that were missing please?

[@knowtwodrugs]

Did you put a new chip in it or anything? Everything I've read says that you won't see much performance gains unless you retune to match the changes. Sounds awesome, and the work is spot on.

[@blackericdenice]

He want see any gains until he change the cam.

[@dalton3231]

+blackericdenice you're a youtube troll, get a life. I've seen a couple of your videos and they suck with lots of bad and false information.

[@blackericdenice]

Dalton Johnson I wish I could see some of your videos.

[@gruenkejoey]

blackericdenice have you ever done any simple mods? i had an 89 k1500 with a tb spacer, 6" open air filter, long tube headers and a chip. i gained a bunch of tq and hp. beat out lots of car and trucks just by doing a few simple mods.

[@blackericdenice]

That bull shit didn't do nothing but waste your time and money. Until you add NOS, cam or boost. Your engine is not getting the air it need to make more hp. I just can't believe how people think what you did was fruitful.

[@dalehobgood9419]

Im rebuilding my dads old truck and i was wondering if i should put different injectors in the tbi or leave it alone... only thing wrong with the truck was that it blew a rear main seal and sat for 10 years... going to get it running this year and thinking about designing my own air intake for more air in.

[@FuelInjectionSucks]

+Dale Hobgood Only if they don't work.

[@dalehobgood9419]

+Fuel Injection Sucks Ok thank you

[@jeepguy4ever30]

leave the factory injectors alone. Just flip the lid upside down on the stock air cleaner and screw it back down. Its free and works. watch engine masters air cleaner shootout for proof on the engine dyno.

[@MiahDougie1]

Great vid & Job am an import Dude but I Luv my K1500::-) but shes miss firing thinking of troubleshooting processs of ilimination TB, map sensor, temp sensor. She leaked water not sure from where and is been sitting for a month during that period of time. any suggestions. thanks

[@purestress2]

I have a 1990 chevy Silverado and the vacuum hose is cut to what I think use to be the vacuum tank. Well it doesn't have one cause my mechanic said since a new intake was put in it doesn't need it so we just covered the port. I'm trying to learn more so I can keep working on it myself. If you don't mind would you walk through with me every now and then?

[@FuelInjectionSucks]

There are not many vacuum lines on these motors. One to the MAP sensor, one to the EGR solenoid, one to the brake booster, and one to the PCV is about all I can think of. It's not like older carbureted motors. Most things are electronic on TBI motors.

[@purestress2]

+Fuel Injection Sucks Yeah he told me it use to go to the Brake Booster but that since a different intake was put in that I didn't need it. So we closed that valve. But now it seems like the brake pedal is loose and almost touches the floor with a shake and squeals now when I brake! I bought the truck with so many things missing it's been difficult trying to fix it. Our Engines look similar and want it to run like yours.

[@FuelInjectionSucks]

The brake booster makes it EASIER to press the brakes. With it unplugged it should be very hard to press the brake pedal, but they should still work. It should be plugged in, but you have other serious brake issues if you have a soft pedal.

[@purestress2]

+Fuel Injection Sucks he said my intake is better but I'd kind of rather have the original so I can hook up missing parts and leave it original. What's your opinion? Is he right?

[@purestress2]

+Fuel Injection Sucks Oh ok. So is it alright that we closed the valve. He said something that the Engine creates it's own vacuum.. Pretty much lost me there and what it had to do with being connected to the break booster.

[@Cheeques2002]

I had a tbi spacer on my 94 silverado. It seemed to make midrange power where it fell on it's face before. This was after the e3 plugs, cold air intake with k&n air filter, and 19" chambered mufflers which I used a splitter to get dual tail pipes on one side out the back. I wish I didn't swap it for a 96 mustang gt, I don't have thst anymore either. Btw- how does the truck pass smog with no cat?

[@blackericdenice]

It don't pass smog with no cat Goober.

[@outlawCaston]

Al Marino it will pass if you use the after market replacement with the o2 sensors ! they even make the headers with o2 sensors so have a nice day !

[@outlawCaston]

***** it does pass if you get the after market replacement parts with the o2 sensors have a nice day !

[@blackericdenice]

OutlawCaston Caston If a car had a cat from the factory and u remove it. It want pass an emission test. The exhaust will be to untreated.

[@FuelInjectionSucks]

***** It passes because we don't have a smog test.

[@BigZu423]

Video on how to remove these??? And great performance parts for it? I have a 1986 monte carlo 4.3L fuel injected 262

[@FuelInjectionSucks]

Find part 1 of the video

[@FuelInjectionSucks]

Bolt-on is just a suggestion apparently to most companies.

[@billypilgrim7838]

real good,the sound went south alittle

[@garyc134]

After you installed the adjustable regulator, what psi did you adjust it to?

[@FuelInjectionSucks]

gc Seems to like 13PSI. Stock is 12.

[@asaneuwillerjr193]

Quick question. I bought the same kit for my tbi and I have trouble adjusting the fuel pressure. It's impossible to reach the red knob by hand. What did u do for urs?

[@FuelInjectionSucks]

I turned it by hand. It's not fun to get to.

[@asaneuwillerjr193]

Yea I didn't get the spacer so I literally have no room to reach it so I just ordered that hoping no I can turn it 😂

[@chrystalpaugh9458]

@@FuelInjectionSucks i have a van, i can reach it from the driver seat, just need to instal it...

[@jamest4363]

I have an 1989 chevy .what should the fuel pressure be?

[@FuelInjectionSucks]

+James T43 12psi regulated pressure.

[@V22D]

can I just put a TBI fuel pressure tap adapter instead of the gauge. so I can only tap into it whit the gauge to check the fuel pressure

[@FuelInjectionSucks]

+Vicente Dominguez I don't see why not.

[@V22D]

+Fuel Injection Sucks thanks for the help I just wanted to make sure

[@robmacfarlane5864]

You can put a pressure gage on the incoming fuel line. You will have to buy the adapters that let you screw in the gage. You will also need to change the pressure spring in the TBI fuel pressure chamber. That guy from TBI Mods sells a higher pressure spring.

[@robmacfarlane5864]

Vicente--------I took the fuel line extension fittings I got from LMC and drilled and tapped 1/8 pipe tap. You could do the same, and just put a pipe plug in the hole if you don't want to have the gage in all the time. When I checked my fuel pressure it was at 12 lbs. which is normal. If you want to increase the pressure, you need the 18 lb. spring from the TBI mods guy. You might be able to buy the fittings with the 1/8 pipe port already in. Check out Jegs. Personally, I don't think I want the pressure gage in the engine compartment all the time. If it ever broke, the truck would catch on fire.

[@jacksonroxmysox1]

where did you get your kit

[@grandparolie]

I like the mods you did except for the spacer it does nothing but cause problems.

[@tylerschwartz4327]

Xavier Xavier not on tbi. Tbi engines love a tb spacer.

[@grandparolie]

Tyler Schwartz now on your TB you did a good job but like on my truck the spacer did nothing we even have before and after with a dyno and it only gave me trouble in connecting the fuel line I took it off and returned it with the results now what did help my truck was the underdrive pulleys I don’t have the one on my water pump and I regret it now my alternator runs low and my A/C blower doesn’t blow as much air and on a hot Texas day the pulley for the water pump would help it keep cooler another thing that helped was the posi and 3.73 gears. Oh I like the gauge you put on. 💯👍🏼

[@johnknight9452]

It's a orange wire with blk stripe

[@2boredfortv]

I have an 87' and the wire I disconnect to set the timing is on the driverside firewall next to the master cylinder; having to go under the dash for anything is a bummer.

[@jackthemap1885]

I laugh every time I see someone with windshield wipers that don't park correctly... I laugh in pity because I personally know it is the most frustrating thing while driving down the road in the rain when they park halfway through their cycle.

[@therocket280z7]

If there's that much of a difference between muffler and no muffler, then the muffler is significantly restrictive.

[@deanobabino833]

Ahh, good point. I`m sure going from the restrictive cat to no cat would be a decent gain. Did you increase fuel pressure any? Do you know what it was baseline?

[@benmoore3170]

I can relate to this dood.

[@purestress2]

For one it's cause you look like you know what you're doing and two our Engines look the same.

[@groveharmon804]

divoom sapa de lemn

[@w9x7cv3vg6]

hey now...take that truck out on the big highways ha ha,good jobmnow u can do mine..what kinda welder was that,i should know ! thanks

[@thedobermangang3503]

DO YOU RESPOND TO ANY COMMENTS

[@FSEVENMAN]

Lol, true enough, you have to flip the lid....

[@angiesmith9196]

Flipping the lid causes a loss of power. All your doing is sucking hot engine compartment air increasing the intake air temperature and dropping the air charge, lowering the amount of power that can be made. Simple thermal dynamics

[@FSEVENMAN]

@@angiesmith9196 I see where you're coming from but I disagree perhaps I should have mentioned I have a ram air 4 style hood with 2 large openings that flow ambient outside air directly toward the air cleaner it's absolutely getting cool air at speed....

[@123killlerz]

hi this is the spacer is work withe tbi engine 5Lin chevy camaro thankssss

[@UncaTuck]

And your shirt off?

[@geovannymerlos1938]

tengo un silverado 1993 y no arranca pongo gasolina en tbi y arranca

[@billypilgrim7838]

+Geovanny Merlos speak English or go home

[@medvetrovm]

+Geovanny Merlos no hay la presion de gasolina necesaria , por lo que debes remplazar la bomba de gasolina!

[@geovannymerlos1938]

+tusombra sonbra ya cambie la bomba y pero no me actiba inyectores ni chispa en bobina

[@medvetrovm]

si no hay chispa desde ahi , y si este modelo consta de modulo de encendido es ese la falla o a su vez chequeale el distribuidor si estan conectados los cables correctamente y si no estan quemadas las terminales del rotor y cables muy viejos desde la bobina al distribuidor y los de bujia

[@medvetrovm]

Geovanny Merlos la chispa empieza en bobina pasa al modulo de encendido si este modelo consta de ahi va al distribuidor o rotor pasa por los cables de bujias y produce chispa , chequea si estan conectados los cables correctamente o estan muy viejos (CABLES DE BUJIA SY CABLE DE BOBINA AL DISTRIBUIDOR ROTOR) y si no estan quemadas las terminales del rotor (distribuidor) , en ese orden el rotor debe ver al primer cilindro para que empieze la chispa en orden de encendido

[@susancurry9050]

thanks now I knnnow how to rebuild my carbutor

[@FSEVENMAN]

My94K1500SILVERADOROCKS

[@fastsofaracing]

fuel injection sucks, shows video about fuel injection. Cool vid tho....

[@gobloit4473]

A mod like that takes away from your low end torque.... just saying

[@WS6xMASTER]

Which one are you talking about. i am guessing the Y pipe because the factory one flows alot less.

[@jeepguy4ever30]

Since the swirlport heads, peanut cam, and factory exhaust manifolds are the real restriction on this engine, It probably helped more than it hurt.

[@FSEVENMAN]

gob loit Perhaps but these model years were notoriously low horsepower and high torque so maybe he can afford to use some of that torque....