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87 350 TBI motor swap with built L-48 350

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Old 01-31-2013, 04:05 PM
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Default 87 350 TBI motor swap with built L-48 350

Hello all

Well I bought a 83 blazer that has a 87 TBI motor in it with the 700r4 and its getting tired.

I have a brand new built 1970 L-48 350 with all the goodies on it and would like to swap it in if its possible.

My question is will there be any issues using the TBI? can I just yank this motor out and drop in the old built L-48 and then bolt the TBI onto the intake and call it good?

Thanks in advance for your help.
 
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Old 01-31-2013, 04:45 PM
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Why would you put a restrictive stock TBI setup on a built motor? Stock TBI relies on a known set of engine operating parameters. You need a specific camshaft, need the TBI distributor, all the sensors and the ECM.

Just buy an Edelbrock dual plane manifold, 600-ish cfm carb a set of headers and a MSD HEI dizzy. Power wire for the Dizzy, separate power for the choke, fuel for the carb and vroom-vroom...
 
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Old 01-31-2013, 05:04 PM
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Originally Posted by 70-K5
Why would you put a restrictive stock TBI setup on a built motor? Stock TBI relies on a known set of engine operating parameters. You need a specific camshaft, need the TBI distributor, all the sensors and the ECM.

Just buy an Edelbrock dual plane manifold, 600-ish cfm carb a set of headers and a MSD HEI dizzy. Power wire for the Dizzy, separate power for the choke, fuel for the carb and vroom-vroom...
lol, Not a bad idea. I am considering that too, just like how smooth fuel injection runs and if I am ever on a steep incline it wont run out of fuel.

The 350 I have is bored 40 over, weiand stealth manifold, tube headers, thunder cam, roller rockers, solid lifters, peat Jackson gear drive, ported head and have a flame thrower HEI. All brand new and has been sitting in my shop for 3 years now.

So think I should toss this motor in and convert back over to a carb?
 
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Old 01-31-2013, 05:22 PM
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Originally Posted by 70-K5
Why would you put a restrictive stock TBI setup on a built motor? Stock TBI relies on a known set of engine operating parameters. You need a specific camshaft, need the TBI distributor, all the sensors and the ECM.

Just buy an Edelbrock dual plane manifold, 600-ish cfm carb a set of headers and a MSD HEI dizzy. Power wire for the Dizzy, separate power for the choke, fuel for the carb and vroom-vroom...
oh and I do already have all the electronics in the rig right now. It has a running TBI 350 in it currently. I know it will need to be tuned and possible larger injectors. I have some expirince with tuning FI just need to know if it will all bolt up ok on the older 350.
 

Last edited by tech180; 01-31-2013 at 05:55 PM.
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Old 01-31-2013, 07:42 PM
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So get a four barrel intake that will accept a square bore carb and get something like the Edelbrock E-Street fuel injection setup. They make great power, are extremely efficient, and are easily retuned should you change heads or cam down the road.
 
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Old 01-31-2013, 08:47 PM
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What are the specs on the L48?Has it been modded with a larger cam,are you running 202`s on humpbacks or do you have 882`s with 194`s or 202`s in them.Option c you are running aluminum headsLOL.
 
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Old 01-31-2013, 11:32 PM
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the tbi unit flows 450 cfm,its not too bad,but its still a little small for a decent 350. You could slap it together,but you are going to run lean,and its going to need a tune. after all said and done it'll be easier and more efficient to run carb.
 
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Old 02-01-2013, 04:55 AM
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It depends on how much $ could spend.If you can afford it there are some fuel injection systems that can run on your set up.If your on a budget then I would recogmend what Mossy said or convert it back to carb.Another alternitive if you can get all the componets neccasary and have the $ for them would be to run tpi.
 
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Old 02-01-2013, 03:25 PM
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Originally Posted by 1sttimejimmyowner
It depends on how much $ could spend.If you can afford it there are some fuel injection systems that can run on your set up.If your on a budget then I would recogmend what Mossy said or convert it back to carb.Another alternitive if you can get all the componets neccasary and have the $ for them would be to run tpi.
Now you guys got me thinking about running a carb on it, lol. Only thing that I dont like about the carb is this rigs will be for wheeling and may see some extreme angles. But I guess there are carbs that can deal with that too.

If I did go carb should I use the fuel pump in it and a regulator/block off plate or run just turn the pump off and run the maniacal pump?
 
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Old 02-01-2013, 03:35 PM
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Originally Posted by 1sttimejimmyowner
What are the specs on the L48?Has it been modded with a larger cam,are you running 202`s on humpbacks or do you have 882`s with 194`s or 202`s in them.Option c you are running aluminum headsLOL.
Well, I lost the dang cam card for the motor and I bought it 3 or 4 years ago, but I do know it has a thunder cam and solid lifters, its bored 40 over, has weiland intake manifold, headers, flame thrower HEI, roller rockers, pet jackson gear drive and ported cast iron heads. It only has about 500 miles on it so its still brand new.

Since this motor is not stock it may be better to go with a carb uh? Sorry for being such a newbie.
 


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