The moderators should just move the GM TBI postings to a new thread... having them on the same Thread is confusing....

The GM EFI and the current conversions from a carb to fuel injection are very different. Some people do not want to or are not able to use a computer for tuning or move pins around in harnesses. My posting was to show the "other way" to use fuel injection by removing a carb.

I did all that with the LT1 fuel injection in the S1 LT1/700R.. this time I wanted to try out the "easy way"... getting too old for the extra work needed.

Both ways have troubles, both have solutions... they are different.

 

Put your helmet on Carl lol...

 

Alyn:


Tis been a while since I had a tin pot GI helmet. Had a liner around here some time ago? where it went, I dunno.


And even longer since a "sorta' racing helmet. 1948, I think,
and, I think it might of been a foot ball helmet...


But, I do have a hard hat, I think, in the garage. Used when I was working and needed one to get on a construction site. Plastic probably over the hill.


Oh, well, some have called me "hard headed", so.....


Carl

 

i see its coming to FULL MOON again!

having watched this kind of postings its gets hotter about every third full moon!

and nobody agrees to there lunar abilities.

its great to be human

 

I do not have a argument with the GM EFI systems... been there - done that. The two ways are totally different methods with the same results... drive the car down the road.


The GM EFI just takes a lot of skill, a computer and electronic experience to adapt to other cars and make them work completely. Digging through wrecking yards for the parts can make them cheaper, using all new parts??


This new method is just removing a carb, using the same manifold and adding the throttle body, fuel supply and the harness and is all "plug and play". It is adaptable to other engine 4, 6 or 8 cylinders.. there are some benefits along with the problems that come from trying to fit new stuff into cars that did not come with the proper designed room for the equipment.


But hijacking a thread about one system installation.. and then saying the "other way will not work"??

 

Well, I merely saw it as TBI vs TPI ! Technical hijack, perhaps ?


The present Mabry solution. The Murry Solution. The Hutchins, almost solution and the Sanchez hoped for solution.


At least I am getting something out of it.


Carl

 

Thanks all to the inputs to this thread. There is a lot of great info in here for the community of Lumpers.

 

my V12 uses a standalone computer system, with a hand held for adjustments, 255 break points, for the fuel curve!

been great since 1994, but has been upgraded 3 times, because technology keeps moving up, and has more performance and smooth response, along wit better MPG!

i did it because the ancient Bosch D was a total mess!

yes ,some time to get it programmed correctly, but a great learning curve .

 

all of this thread is so helpful for those of us planning to lump. is that a verb?
keep it coming!


geneo

 

Trunk area is all done except for the wiring plug for the changeover valve.. it is ON the way... add the needed wires and then I will power it up and check for any fuel leaks and set the fuel pressure to 43 pounds on the fuel regulator up front.

Had to take two photos to show the items from their proper angles.. fuel system is 100% new from the S3 filler caps to the throttle body on the engine.. one short section of Jaguar metal fuel line has been retained since it is complex and goes around the IRS area.

Hi pressure fuel injection hose was used anywhere there is high pressure plus the correct clamps. There are two pre valve filters and one post pump filter that is for the high pressure system.

This is same fuel pump and changeover valve system used on my prior 1972 S1 LT1/700R with the stock GM fuel injection. Spare tire barely fits in there with all the surrounding "stuff".

 

@Icsamerica: thank you for the link with the schematics.
@alynmurray: I will contact you via email soon.
@Roger Mabry: My apologies for disrupting the flow of your post. I thought it was a
forum = discussion.

 

Maybe we should start a new thread and call it Fuel injected Lumps - How To..

Then folks who are thinking about "doing the deed" can see what needs to be taken into consideration, and the various ways to go about it, Sanchez comes to mind with his recent post looking for some direction/input as to how to do the swap (350 TBI) step by step - with which I have offered to help him (or anyone for that matter).

We may find out that there are some really good proven step by step ways of converting to TBI or TPI or any of the newer engines. Then we may see the sale price of the good well done ones increase in value.

Often overlooked is the fact that if you build your own, (or modify an existing FI system), you will, in the end, know how to trouble shoot the beast. Plug n play is great,... until something goes wrong. "who you gonna call ? " Building your own is part of the car modification hobby...it adds to your ability to understand what is happening when the car stops running or starts running poorly. I for one will place my money on the GM systems engineers every time when it comes to simple effective FI - they are proven systems. And if the Jag (with its new GM TBI wired exactly like it was in its original car) decides to have issues, I can drive it into any GM auto repair,....they plug into the "on board" ALDL . Presto ! Chango! and as Willie says "on the road again"...with GM factory parts {new or used) or I can plug it into my laptop using ALDL software that also works on my Galaxy smartphone ...so there is an app for that, as well... lol


(DId you know Corvettes had TBI? Check out 1982 Crossfire Corvettes.)

 

quick question;
seeing that GM went from TBI and advanced to TPI, why would they do that if TBI was suffcient ?

gotta be a good reason , much R&D any money spent for the change??

GM should have kept the 1963 factory FI systems, when set up correctly they more than satisfied most people?

when independently tested they were equal or better than any elec.FI system, if mass produced cost would have been acceptable.

as i was around then, most tech guys didnt have the nuts to work on them!

and actually the 1963 FI was quite simple, and with some modern elec. fuel pumps it would be more dependable!

stop and think,if GM had kept 63 FI and kept on with R&D developments using some modern tech ,i can just imagine what could be !!

 

The answers to your question. TbI is really good - when it was first available it was used on Corvettes (cross fire - 2 TBI units - one for each cylinder bank ) and Cop cars - 350 c i with large capacity injectors but still TBI. TBI was used for economy and low RPM operation, even the heads were manufactured for these purposes. As opposed to TPI which was found on cars (Camaros Firebirds) that relied on HP rather than torque. Thats why you have the zoomy intake on TPI and higher RPM operation that enables the tunnel ram effect of the TPI intake. Then came LT1 with reverse flow cooling
Another reason for computer controlled EFI. Granularity. Using digital calibration you can use any given FI system and fine tune it more precisely if it is controlled by an ECM with its various sensors.
The old Corvette HP Chevy FI relied on a vacuum signal much like the old Jettronic Bosch system as licensed to Lucas for the Jags etc. Clunky by todays standards and then there is the emissions issues to be addressed and granularity comes to the rescue, super fine tuning of the computer chip spark and fuel tables. All auto manufacturers abandoned the old FI systems and went digital - just like anything else today...phones.. TVs... anything electronic needs granularity for fine tuning. lots of bits n bytes / faster chips (baud rate) = more flexibility.

 

What's the '63 fuel injection system? GM debuted it Rochester RamJet Fuel injection system in 1957.

World War 2 was won, in part with TBI. American fighters and bombers used a simple vacuum based TBI fuel system that could handle the maneuvers that would have emptied a carburetor bowl. They also used superchargers for altitude and methanol injection so they could run extremely lean under light load and extend their bombing range.

The Germans used a much more sophisticated mechanical and direct fuel injection that was complex and had too many parts and was far less flexible, less field serviceable and less reliable. Carburetors were simple. Perhaps GI's recognized the complexity of the Rochester early Fuel injection and rejected it.

 

Yep. Chev passenger cars and Corvettes and Pontiac offered an FI in 57.
Some still willing to pay a big buck for a good one.


Hot rodders and racers did get into FI. Stuart Hilborn designed and offered one. His dry lake car went super fast. Indy and sprint cars dumped carb's and went Hilborn early on.


But, some use LT1's sans FI, adding a big carb???


I'm tryiong to recall the badge name of the Cadillac, based on a Chevrolet body that encompassed their version of FI. A cottage industry developed to chop them to two seat roadsters.


I am very pleased with my LT1 system. Sure took a lot of learning by me. Lots of help, though. I even wrote a "white paper". Lump Thoughts. I wonder where it is. Lost in old hard drives???? On paper somewhere in my lore.


Carl

 

The Seville. From 1976 to 1979. It was a Cadillac that was based on the same GM platform as the Camaro but unlike the Camaro...it had rear disc brakes. It also was a unit body car with a front sub-frame. On the Cadillac the front sub-frame had rubber bushings for smoothness but the on the Camaro it was bolted right to the body.

It used an analogue speed density fuel injection system that was very good. A simple system using just two temp sensors, a set of reed switches in the the distributor and a vacuum sensor embedded in the electronic control unit.

The 2 door chopped version was called the Opera Coupe.

I owned a few of them over the years. So superior to any carburated car I had prior. I had a 1978 which wouldn't start all of the sudden. No one know how to fix it. This started my pre-occupation for things no-one else could fix.

 

That is it. I admired them for a while, early 80's I think. Came close to buying one. One pulled in to the park lot of a local convenience store. for sale sign. $600.00. Exterior fair, not smashed anywhere. Bad exhaust leak. Talked with "slightly out of it" occupants. But, title was a bit wonky and they wanted transport back to their place. Decided there was a huge issue there, so, I passed.


Would've got me into FI much earlier....


A lot later, I bought a very nice used 85 Ford F150 4x4 302. First Ford pickup with FI. It ran very well, although a bit short on power.
Big tires and OD, a bit much.


Carl

 

Hey you guys ,...knock it off !! you are hi jacking Roger's thread (again). He got so pissed off last time, he started a new thread so we would do this kind of stuff somewhere else--- so stop it ,..stop it,..stop it. Only Roger's stuff ...understand? .. . Sheesh !! ....some people... lol

 

OK,Ok, got it.


Roger, please continue your treatise.....


Carl