Greetings,

I have a 89 GMC Sierra with a 5.7/AT. I don't have any experience with TBI. Can someone give me a rundown on the performance potenial of this system. I bought this truck as a second vehicle and am very happy with it. I am reluctant to make any major mods right now, it has 95K on it and not one single gasket on the whole truck leaks. It looks like it rolled off the dealership yesterday. It does have a cat back on it, and I removed the airbox silencer and fender airhorn. Seems like it runs much better. Thanks.

 

NO!

YOU MUST LEAVE IMMEDIATELY

 

Im just kidding

just keep reading the boards and the board archives

 

My dad had an 87 burb and now has a 95, both have the 350 TBI. When I go home I want to fiddle around with it and mess around with a few things. He says the 87 was faster and I agree, not sure why though. I need to figure out what gears he's got and need to help out his air cleaner problem. Maybe I'll give him my 14" drop base considering it doesn't even fit under my hood ....yet.
From what I've read, headers help a lot. They are my favorite bolt on.

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, Jon (350 TBI! getting 23mpg highway)
91 Red RS w/grey int, sq stereo (Alpine v12, kicker solo, MB quart premium etc)

• Holley 670 TB unit w/ 1/2" spacer/adapter
• Edelbrock RPM vortec intake
• 350ho 330hp vortec crate motor
• 8" harm. balancer
• Stewart stage 2 water pump w/160 thermo
• SLP tri-y headers to full 3"
• Rebuilt trans w/ SLP shift kit
• Centerline 16x8's all around
• 36/24 mm sway bars
• Full poly bushings, even motor mounts
• SLP LCA and panhard
• Alston SFCs
• Edelbrock 3 point STB
• Global west steering brace aka wonderbar
• Eibach pro kit springs
• Bilstien high perf. struts and shocks
• All this and I still have AC

My websiteAny questions?

 

What does removing the Airbox do on the 88-95 pick-ups do? Doyou think if you just stuck a open element on a pickup it would work better than the stock airflow?

 

It would work a lot better, especially since a pickup engine bay isn't as crowded. At least most aren't. An open element is the easiest way for an engine to suck in the most air so unless you can have it suck in super cold air, an open is the way to go. Even imports have figured that out. It shouldn't effect torque and might even increase gas milage.

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, Jon (350 TBI! getting 23mpg highway)
91 Red RS w/grey int, sq stereo (Alpine v12, kicker solo, MB quart premium etc)AIM: JPrevost

• Holley 670 TB unit w/ 1/2" spacer/adapter
• Edelbrock RPM vortec intake
• 350ho 330hp vortec crate motor
• 8" harm. balancer
• Stewart stage 2 water pump w/160 thermo
• SLP tri-y headers to full 3"
• Rebuilt trans w/ SLP shift kit
• Centerline 16x8's all around
• 36/24 mm sway bars
• Full poly bushings, even motor mounts
• SLP LCA and panhard
• Alston SFCs
• Edelbrock 3 point STB
• Global west steering brace aka wonderbar
• Eibach pro kit springs
• Bilstien high perf. struts and shocks
• All this and I still have AC

My websiteAny questions?

 

I've found that the regular TBI mods (K&N filter, TBI spacer and exhaust) provide a considerable increase in power over the whole range for not too much money....

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1989 GMC Sierra Z-71 Shortbed
K&N Aircharger, PowerAID TBI Spacer, Flowmaster 40 series
http://communities.msn.com/partycamv20

 

If you want to be cheap, just flip the air cleaner lid over.

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'93 2wd truck
408 sb, vortecs, 454 TBI, Comp Cam, dual exhaust

 

I have done almost all the mods to my 92 GMC 5.7L 5speed. Check out www.bharris.org/92gmc for the latest info. My current configuration is running about 350hp. I which is about the same as the Paxton supercharger ran on the first setup I had on it. Feel free to email me, I love making my truck eat the little mustangs. I still can't beat a good 4th gen though. Maybe someday.

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91 Camaro RS 5.0L Black Convertible 700R4. Owned 3 months bought from 1 owner girl. Working on that stock part.

 

I also have an 87 burb with the K motor. I only paid 750 bones for it and and it runs great so I think Ill save my money for the maro. PS, I fliped the lid and did notice a difference, both in sound and passing gear power. Maybe headers if I dont sell it.

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91 RS W/carbed 350, Vortec heads, performer rpm, Comp cams Xtreme energy 224/230 duration and .477/.480 lift. BFG Drag radials. 3.42 posi,Corvette servoed 700r4, 3000 stallconverter. Edelbrock TES, 3inch cat, flowmaster with single 2.5 inch exit.
Best time yet to come
12's?? :crossthumbs:

This is a Pic of my car in race trim www.tbns.net/billyjay/camero.jpg

Yes I know how to spell camaro- so dont ask. I didnt make the link

 

A friend at work has a chevy truck with TBI and he was wondering if there was a good truck site.He wants to do some other stuff besides engine work.I told him the truck guys come here for tbi.
We're number one!
We're number one!
By the way just did the ultimate tbi mods last weekend.Thanks to every one who posts here.

 

brharris27370-

Do you have the getrag 5-speed in your pickup? Thats what i have in my 91 pickup and i have heard nothing but bad about them. So bad, that gm gave the original owner the choice to switch to a borg warner 5-speed; But my tranny just went out and its got 200,000k on it and I thought it ran good. So I'm picking another getrag up thursday for $400 and only 69k. Thats a steal,

 

My truck has a 700R4. I removed the air restrictor from the silencer as well as the airhorn from the fenderwell. I only had the truck about 2 weeks when I did that. The first 2 tanks of gas gave me 14.5 mpg. After opening up the intake I'm getting consistantly 17.0 mpg. I didn't go with the open airfilter because the engine bays of newer rigs are so tight the only air in there comes through the radiator. I live in the south and it gets hot around here. My next plan is to get a 454 aircleaner assembly. I think it has a much larger snorkle. I also have the severe duty top for a 14 inch chevy aircleaner. I have alot more room under the hood than you guys so I can run a 14 x 6 K&N airfilter and still keep my cold air intake.

 

I will give it to you guys, you do know your TBI stuff better than any sight I have seen so far. I printed out the ultimate TBI mods last night, so I have some more stuff to look into. I think this is onesight that i will be around on a while.

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87 C-10
305 TBI
(yeah I know its a truck, but you are the best TBI guys I have found)
Performance
**Somewhere around a 17.0 @ 85 ish (G-Tech)
*Freshly rebuilt 305 bored +0.030 over (311)
*K&N Airfilter
*Homemade Ramair w/ modified intake
*180 thermostat
*Custom True dual exhaust(Flowmaster 40's)No Cat's
*TD Performance TBI Spacer
*Mobil 1 10-w30
*Redline Water Wetter
**(alot more done, but I don't feel like boring everybody)