350 TBI convert to Carb and Intake

I got the 48 Chevy pickup bought that I was looking at that comes with a 350 from an 88 Suburban. I would like to convert to a carburated system and get rid of the TBI setup. I have read about reaming out the holes to get the bolt to line up, but what are my options on buying an intake for the application? I found the Edlebrock number on Jegs, what other brands and part numbers are made for the application? If anyone has an intake and carb setup they might want to swap for the TBI let me know. Thanks

 

The more I read, sounds like there is more than the intake and carb to consider. Sounds like it needs a new HEI distributor and maybe some other stuff. Let me know your thoughts. I am not sold on putting this engine in the truck by any means and was actually planning to find and older carb engine complete to install. Just looking for some good info. Thanks

 

The Performance Products rip off of the Performer that you see on Ebay comes with the center bolt holes slotted out and angled shims to go under the bolt heads so it can be used on either style of pre-Vortec head. I'd cough up the extra bucks for the Edelbrock myself. Once in awhile one will show up on Ebay but they usually bring damn near new price. There were a few factory 4 Bbl. intakes for these heads too but they would have the EGR pad. Or you could slot out a manifold and make your own tapered shims from thick wall steel tubing and use a slightly larger flat washer on top to hide them.

About the only thing an '88 TBI 350 has going for it is that it is a 1 Pc. rear main seal and should be set up for a roller cam although trucks and 'Burbs usually got a flat tappet hydraulic. The cams and heads from the TBI V-8's suck big time. If it's a low mile core in good shape I'd tear it down to the shortblock, get a 350 Ramjet / HT383 crate motor takeout roller cam off Ebay for $50 and the necessary lifters, retainers and timing set to go with it. Then pick up a set of low mile Vortec heads and the Edelbrock Performer to go with them and bolt it all together. A conservative 330 HP with 390 plus LbFt of TQ on 87 Octane that will idle like a Singer sewing machine, pull stumps at an idle and rev to 5500 RPM with ease. I have that exact recipe sitting in my garage waiting for something to drop it in.

 

If you would learn a bit about that TBI, you would really love it. Easy starting, good fuel economy, nice torque for a stocker, lower wear on the engine. A stand alone harness is afordable and they don't look much different than a carb motor when you put the right air cleaner and brackets on them.

 

I've never had a problem using any kind of carb intake on a 305/350 tbi or tp. Just hog out the centre holes and good to go. Years later still no leaks.

 

If I use this engine, and I convert to carb, do I also need a new distributor? I have read that is true. I will know more about the engine when I get it home this weekend. I am not looking for a hot rod engine, just a dependable engine, but really don't want to mess with a bunch of electronics. Once I get it home I will be able to take the plate off the fuel pump and see if a mechanical fuel pump would work.

 

Yes, you will need to find an earlier HEI with a vacuum advance can.

 

I have 48 Chevy truck with an 89 suburban 350/700R4. I took the TBI off and put an edelbrock performer intake, holley 600, mechanical fuel pump and a mallory unilite distributor on it. It runs great. I got the motor for free and bought the used intake, carb, etc off of ebay. You shouldn't have any problems using that motor.

-Rich

 

Thanks, I am looking at all options. I will know more about it when I get home. Will the TBI setup bring anything to sell it, if so, how much? Distributor should be no big deal, I do have to take the cover plate off where the fuel pump would go and see if it can be adapted to mechanical. I would prefer mechanical. Thanks

 

I'd almost be half tempted to run the TBI knowing what I know now about them. I had one in my '89 Chevy that Toast has (and just sold) that had almost no sensors on it, and it ran like a top - hell, even better! Ran solid and strong!

There's a company - and I don't know the name or where they are located - that can get into the computers and turn off (or set permanently) the reading the computer would take from a given sensor.

And, you'd be able to run the stock distributor off of that motor as well, which runs a much smaller diameter cap than the HEI setups.

 

Here's the one I pulled out of the 89 suburban.

 

My setup is going to look very similar to yours. The mustang II front, rack and steering coluum are already in the truck. What headers did you go with, are they a center dump style shorty header? Can't tell by the pictures. Did not know which would fit best the center dump or if I had to go with something with a rear exit. Thanks for the pictures send anything else you might to me if you would LJeffe2872@aol.com. I would appreciate any help from the experts!

 

Unless you're going for a race vehicle, I'll second the reliability of the TBI, even with somewhat indifferent maintenance. Starts right up when it's 90' out, starts up when it's -9' out. Nothing particularly complicated to the wiring, either. We have one truck here with nearly 300,000 miles on the original TBI 305. My Suburban with the 350 has a crazy tall rearend gear, but still moves and has plenty of power for a street vehicle.

But if you do take it off, you can sell the injectors easily, possibly some of the more expensive sensors (EGR valve for instance) too. Seems to me the EGR when mine needed it was $75 and that was the Rock Auto price.

 

Just looking for a cruizer, not a big hot rod. Thanks for all the good info.

 

Gm makes a stock intake for the center bolt heads ... it 2-3 years only in the older square cop cars !!!

there available all over

 

Stay away from the very cheap intakes the gentleman ahaed of me mentioned. They don't fit correctly. Hole for dist. is off just a tad. had a TBI in a 54 chevy and a 72 p/u. No complaints at all. $0.02

 

I put a 1995 350 with TBI im my M1 truck. Like RUSTYNEWYORKER says, always starts, good on gas, still sounds like a V8..............

 

The tbi intake has coolant running through it without the exhaust crossover. May be cold blooded in cold weather.

 

You can get vortec heads in the junk yard. They will swap right in. Then you get a carbed vortec intake and can use a variety of carbs. I'm doing this right now. I chose the vortec heads because they are thought to be the best heads around right now for sbc's. 350 w/vortec heads and carb can easily make over 400 hp.

Do a google search for vortec heads. There's an article at one of the hotrod magazines that used scoggin dickey heads (vortec ported +) and detailed what they did to make about 450hp.

Only real issue with the vortec heads is limited lift which restricts cam choice but that can be fixed to for reasonably cheap.

 

I know this is an old thread but thought I would add my $0.02 to the mix. I had an 89 full size chevy that the computer decided to die on me in. Edelbrock makes a carb intake that bolts right on with no fuss or hassle, seems to me that I only spent a little over $100 on the thing. I bolted it on and cut every wire that went to the computer, and threw the rest away. Grabbed a HEI distributor from a buddy and threw it in. One day conversion with disassembly and installation, super easy and the thing is still running like a top!

 

jd holmes....i know this is an old thread but i am getting ready to do the same thing...but i am wanting to install bigger cam. mine is a 350tbi bored .30 over with rv cam...wanting to install a little bigger cam, vortec heads and chang to carb what else do i need thanks

 

vortec heads need a matching manifold, and may need new springs and /or machining to accept the cam
depending the specs. If you keep the cam reasonable the stock heads are good, make sure you use self
aligning rockers if buying new heads, and be aware the exhaust ports are higher and the exhaust bolts
are about 1/4 inch different in height so old manifolds/headers will have some reversion issues.

 

Like some others input,,, Think about keeping the TBI not a complicated system and damn near fool proof,,, You can get a GM or edelbrock performance manifold pretty reasonable,, put a small cam in it with headers and look around you can find a Holley Throttle body replacement used pretty cheap, Get a performance chip for the computer and you will be happy with it as a cruiser it will break the tires loose and with the right gearing still get 20-21 mpg out on the highway. I ran this set up ,Not a race engine but runs fairly well and definitely a cruiser,,and as said before starts and idles at 10 degrees or 100 deg with just reaching thru the window and hit the key...

 

when i removed the 350tbi from k5 blazer i left all wiring and computer with blazer. so say i stay with tbi it is already bored .30 over and has rv cam installed. If i wanted to install a bigger cam what would you reccomend? Also i would need a computer and harness correct?

 

I wouldn't go much over a cam with 220 dur at 050 lift and max lift of around 500 ,you may already have that.. Yes you are going to need the computer and if you have the harness it will make things easier,, you can eliminate what you don't need... Pm me I may have some extra stuff

 

well i think i might just stay with tbi but i will have to go to junk yard to pull an ecm and wire harness...so your saying adding a edelbrock performance manifold and holley throttle body replacement will also increase hp

 

Bolted a pair of 305, swirl port heads onto my nephews mild 350 in the 51 Bus Coupe. We got the heads for free with 14K miles on them, and although swirl port heads are supposed to be junk, and limited to about 4500 RPM, the motor will buzz to 6000 very easily. Tossed on an old Weiand single plane intake, elongated the center bolt holes, and bent some washers so they function as "wedges". No leaks, motor runs good, and parts were cheap or free. Even the 625 CFM "Edelbrock" carburetor is a collage of three different carbs. I am Butch/56sedandelivery.

 

I am going to get a full ration for this, but I am a TBI fan. I am in the middle of replacing the Weber 32/36 on my Falcon-6, with TBI. It is a driver, and fuel costs matter to me.

 

can you run a stock fuel pump on this block?

 

I know this is an old thread, but I'm thinking I'm dealing with the same issue on an '88 tbi 350 and I've searched for help with getting rid of the wiring and computer and you're the first I've found. Could you tell me what sensors and wires you clipped and how you made the ignition cylinder work without the computer?