Fi on stock intake manifold

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Confusedcuda

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Was wondering if anyone had experience with this, can you you install like a FItech Fi system on a stock manifold? Like a 340 iron manifold thanks
 
Yes, you can. The FI doesn't care what the manifold is made of.
The factory 340 manifold is actually pretty good.
Edit: It may be necessary to block the heat crossover, but that's the only potential issue I can think of.
 
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I had 2 Fitech throttle barrels F.I. on a gen2 hemi stock 2 4barrel manifold and it worked.
 
any intake will work with TBI. they use single planes with MPFI as its easier to get the injectors on the same plane for the fuel rails. Also MPFI is a dry intake so shape has little bearing as its just air, look at some of the modern plastic intakes: more like bags of snakes. TBI still is wet so there still is a chance of it dropping out of suspension around all those turns.
 
I would have to ask why wouldn't it work?
 
I would have to ask why wouldn't it work?

Well from the way I think TBIs work is they are not an on demand per barrel fuel delivery like a carburetor is. SO intakes that draw air from all 4 barrels for each cylinder (single plane) work better because fuel from the TBI is delivered equally to each barrel. If a cylinder is only drawing from one or two barrels then its fuel mixture is going to be screwy at lower rpms, because part of the fuel it needs is being delivered to barrels not being used at that point. It all averages out in the end, but it isn't as efficient at lower rpms.
 
Well from the way I think TBIs work is they are not an on demand per barrel fuel delivery like a carburetor is. SO intakes that draw air from all 4 barrels for each cylinder (single plane) work better because fuel from the TBI is delivered equally to each barrel. If a cylinder is only drawing from one or two barrels then its fuel mixture is going to be screwy at lower rpms, because part of the fuel it needs is being delivered to barrels not being used at that point. It all averages out in the end, but it isn't as efficient at lower rpms.

I tend to agree, but if it was all I had, I'd slap one on in a minute. Not that I'll ever run EFI. lol
 
That is why they cut the center section between the barrels out of a dual plane manifold for TBI.
 
Well from the way I think TBIs work is they are not an on demand per barrel fuel delivery like a carburetor is. SO intakes that draw air from all 4 barrels for each cylinder (single plane) work better because fuel from the TBI is delivered equally to each barrel. If a cylinder is only drawing from one or two barrels then its fuel mixture is going to be screwy at lower rpms, because part of the fuel it needs is being delivered to barrels not being used at that point. It all averages out in the end, but it isn't as efficient at lower rpms.

I've run the older Holley 2BBL and commander and then Holley HP computer with 4BBL TBI on mine with no issues. This was an Edelbrock "RPM" I'm not absolutely certain, but "I think" the manifolds used on the late 80's LA factory TBI engines were also 180 manifolds. Maybe someone has one to confirm, mine is hopelessly buried below outboard motors LOLOL

Can't tell for certain these photos sure look like a 180 manifold to me

318_EFI_Intake_Pull-17-1024x768.jpg


318_EFI_Intake_Pull-16-1024x768.jpg


Another shot. Looks to me like the divider has been cut, so don't know what it was from factory

PICT0074.jpg
 
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I didn't say it wouldn't work I just said it doesn't work well, oir as well as it could. There was an engine masters video that pointed this problem out, but they didn't say why there was a problem.
 
I’m pretty sure that’s the way these are made.

If I were going to use TBI with a 180* manifold, I’d def reduce the height of the divider...... and if it was a manifold with 4-holes under the carb...... I’d make it more like one square hole.

91D2B111-A4ED-469A-AA68-16CAE54B0F7D.jpeg
 
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