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I have a 5.7 350 in my 89 burb v1500. Im looking to convert it to a 4 barrel carb set up. Looking for suggestions, tips, and advise. It looks like the Edelbrock 2104 performer is the way to go for intake. I found an awesome deal on a Torker 2 bit it sounds like it won't fit the cast iron heads. Also advice on aluminum vs cast iron intake manifolds? I'm going to convert the top end only. Carb, manifold, distributor, fuel pump. I have heard lots of different options on what will fit and what won't. I have a budget of about 1k so I have been trying to find used items that are high quality. (Easier said than done lol) Thanks for any advice you would like to give!
 

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I'm open to any advice, been doing lots of research online. I would really appreciate any conversation about experiences with tbi in older suburbans or carb set ups.
Thanks
 

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From what I can tell the 350 block and stock heads are similar from the 70s to the late 80s? I found a stock GM cast-iron intake manifold from a 70s 350 #340261 dirt cheap. Anyone have experience going from a tbi on a 89 350 to carb? I'm crossing my fingers this first part of the puzzle will fit. Im thinking the next piece will be a quadrajet 4 barrel. Maybe an Edelbrock if I can find a cheap enough one.
 

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the best advice most people will give you is, dont do it. I will give you other advise though.... go to www.gmt400.com these people will guide you either way you decide. they specialize in only these trucks and there are many people who have done the carb swap and got it dialed in perfect. people who couldnt and went back. and theres the people who can help you fix the TBI or even upgrade it.

Fuel injection is superior to a carb but many will argue that fact.

take care.

Al
 
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Thank you! I appreciate the link, I will go check it out. I am looking to go as low tech as possible which is one of the reasons for the switch.
 

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Looking for suggestions, tips, and advise. It looks like the Edelbrock 2104 performer is the way to go for intake. I found an awesome deal on a Torker 2 bit it sounds like it won't fit the cast iron heads.
Keep in mind that TBI heads and intake manifold 2 center bolts on each side are drilled at ~72* (IIRC) so, in order to bolt an older manifold to the heads, you'll have to oval out the holes and use elongated washers. That's why they won't fit.

Are you going to eliminate the ECM completely? It's not going to be a happy camper without the sensors and computer controlled distributor.

Also advice on aluminum vs cast iron intake manifolds?
The stock TBI intake is aluminum, saves some weight but not much else. Now aluminum vs cast iron heads is a different story but, with a budget of $1000, it's pretty much a moot point.

I agree with Al, if it were ME I wouldn't do it.
 

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Those are all things I didn't know and will have to do much more research into. (Project put on hold) This has been really eye opening. Thank you for the info, you guys have saved me a huge headache and lots of time. Back to research I go!! Lol
 

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Those are all things I didn't know and will have to do much more research into. (Project put on hold) This has been really eye opening. Thank you for the info, you guys have saved me a huge headache and lots of time. Back to research I go!! Lol
Glad to help. I'd suggest you put together a plan of what you want like, more low end torque, better mileage, faster ETs, etc. Then do some research on what you need to accomplish this with whatever combinations of parts and tuning the ECM. Unfortunately the TBI has very restrictive heads and a peanut cam. You'll want to get it to breathe better from intake to tail pipe. Your EFI system is fairly simple and very reliable as is. With the proper diagnostic tools and some help (if needed) you can troubleshoot and repair this thing on your own. Enjoy!(y)
 
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