Tuned Port Injection - 30 years old
 

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October is customarily new car introduction month, that would make TPI 30 years old. The year 1985 was in the heart of my formative automotive years. I was just learning how to rebuild Quadrajets, and I remember the indroduction of TPI as some mystrerious new space aged induction method. Back in 1985, the small block Chevy was 30 years old. At the time, it seemed that 1955 was a much farther back in history that 1985 seems to be now.

Re: Tuned Port Injection - 30 years old
 

I look at that picture of the TPI, and it strikes me.
1) the exhaust is coming out of the side, like it would be in a FWD vehicle.
2) The transmission or whatever hanging on the back looks like a FWD version, or something else for testing, not really sure. It appears to be an automatic of some sort with the servo on the side, but it does not appear to be 700R4 or 4L60 (might need help identifying this thing)
3) the Engine is missing all of its stickers, like the one on the Harrison A/C unit and the alternator.
4) It is an 88-92 serpentine setup...

Cool pic tho, thanks for sharing.

Re: Tuned Port Injection - 30 years old
 

Really when you break down a TPI system they are simple in comparison to some of the new engines out there...

I am not sure if we have gone as far as we did from 1955-1985 from 1985-2015, as it seems there were greater leaps in technology between 1955-1985. WE seem to be rehashing old things and making what we know better.

I think many people do not realize that the port fuel injection in a production vehicle goes back to 1976, Cadillac had an engine that had injectors on every cyl. As did Nissan (the Datsun 280Z in 1976 had a straight 6 with 6 injectors.)

John

Re: Tuned Port Injection - 30 years old
 

Having owned and restored a 1956 Corvette including rebuilding the entire engine by myself (although I had an expert rebuild the carb to NCRS standards), I would take a TPI engine over it anyday! Setting the carb using a vacuum gauge or setting dual points with a dwell meter is like black magic compared to TPI with it's sensors I can clearly see and control with a laptop and a cable.

Re: Tuned Port Injection - 30 years old
 

If both a carb and a TPI was in good working order, I think in so many ways the TPI is more drivable too, throttle response is faster, just overall better for a street car. There is no comparison IMHO...

Granted, my 87 Formula with the LG4 was one of the best carb cars I have ever owned. Mash the throttle twice, and it would fire up like a FI car... But I have not looked back either...

John

Re: Tuned Port Injection - 30 years old
 

That exhaust routing is F-Body stock. Right behind the front tire before the 90* bend toward the rear and the 30* bend into the cat.

I figured auto as well, just without a tail housing. I am not familiar enough with auto models to guess any closer.

Good eye.

88 was different, that is 89-92 belt routing. :)

Re: Tuned Port Injection - 30 years old
 

TPI was good for it's time, but it could have used improvements, especially for the 350. It helped start off EFI performance in Chevrolet and brought back respectable power. They've come a long way since!

Re: Tuned Port Injection - 30 years old
 

The Exhaust from the Left side appears to go in front of the bump of the Oil Pan, I would expect the exhaust to be back further slightly...

I have heard this, but not sure of the differences. They appeared to be basically the same tho, not sure how to tell the difference...

John

Re: Tuned Port Injection - 30 years old
 

Left exhaust DOES actually run slightly forward as it transverses under the engine, in FRONT of the oil pan sump.

The serpentine belt routing was changed in a TSB to run from the WP to the crank, and then to the AP in attempt to quiet down that noisy R4 AC compressor.

The problem with the transmission in the picture is that for some reason, it has the tailstock removed.

Re: Tuned Port Injection - 30 years old
 

More than that, the Trans has been cut in half.

We don't see the other side of the engine, likely sectioned out to expose the pistons and such.