Well I took a couple of hours this evening and started modding my extra tbi. It's half done. I cut the pressure regulator from the pods this should help considerbly with air quanity and fuel atomization. I'l tap and thread the holes and relocate the pressure regulator somewhere behind the carb, runs some tubing into the carb and onto the pods. Need to make a plate to cover the hole, np there. Here's some pics.

 

what are you going to do to cover the hole?

 

I have a some copper sheeting I though I would cut it to size use the two screw holes to secure it and put a couple of holes for the fuel lines with rubber grumets.

 

Here's the plate in place with hoses.

 

You may be on to something there. Does it look as if it has opened up a good bit of room for airflow? I've removed my in-tank fuel pump and am now running a Holley Blue Pump. The Holley pump came with a regulator, which I was running turned all the way up and letting the TBI's regulator(which I've made adjustable) control the fuel pressure. I've now removed the Holley regulator. At one point I was thinking about a way to do away with the TBI's regulator and use the Holley regulator. I'll have to take another look at my TBI unit after seeing how you've cut yours off. I probaly won't be running the 305 and factory TBI unit much longer(around 5 or 6 months at least untill the 4bbl TBI'ed 388ci is ready to install), but would be willing to expermint a lot with it untill then. Though I still got a few issues to work out on it now. I hope to have the tank back in in a day or two( the damn rubber hose that runs from the pump to the sending unit busted, so I hard lined it with some 3/8" copper tubing). Let me know how yours turns out. More pictures would be nice too.

 

Just wondering why your doing this? Maybe so the fuel reg is easier to adjust?

 

I'm guessing to allow more air in

 

It sounded to me that he is trying to get more airflow. He might reall be on to somthing. But yes I guess it would make adjustments easier too.

 

The question is does it really make a difference. Does the regulator actually restrict air, or do the small bores already take in all they can? It definitely looks like it frees up some space, but was that space restricting flow? I would be interested to see some flow bench data.

 

Well even if we don't get much more air flow the air coming in from all directions will atomize the fuel better. I'm looking for an adjustable regulator that has a pressure guage, that would be awesome. I will get more pics but I cut it just behind the screws on the pod, the only place you can cut really and threaded some 1/2 npt connectors into the big holes, had to bore them with the dremel first though and then applied JB Weld. used some metal tubing for the small holes and jb welded them in, hope they hold, should though, not that much pressure is really running through this stuff. I had to bend the tube up off the injector pods to get the hose to fit. Have 4 small hose clamps to hold them in place. I can really adjust the height of the pods now also. If someone has a way to test the flow in the oregon washington area I would be willing to bring the unit to them. I'm also going to use a projection manifold so it should flow better along with some 416 heads.

 

Pic of pod housing

 

9 to 13psi is the stock pressure. I'll have to look tomarrow to see what your talking about JB Welding and threading and such, its starting to sound scary now. I really don't like JB weld and such(I blew a engine cause of a JB Welded hole in a oil pan). Is the car running now?

 

I'm just wondering if it looked like it would be possible to run copper tubing to the injector pod instead of rubber? If so it would be even less restrictive. If there turns out to be no advantages over the stock setup it will still look cool.

Steve

 

The tube went in a long way on the bottom and the top threaded one is tight already, copper tubing would be cool and you could seal it with solder-As long as it does not get too hot. 13psi is not very much pressure so it should hold no problem. I could have soldered the connectors in.

The car has another tbi on it. Believe me when I put this on I will put it through some paces to make sure no fuel is leaking. If it did leak the car would die right away most likely, will carry a fire extingisher just in case. I'll tap on the fittings to make sure they can withstand a decent amount of torture. I was thinking of using some nylon tubing that has a smaller outer diameter and can be heated and bent.

There's more restriction in the internal pathways than there is in the adapters.

A 10-25 psi regulator should be fairly cheap, might be able to get one meant for other purposes.

I think it looks cool also LOL If you polish the thing up you could put a plexyglass top on your air cleaner with a light in there

 

After looking at my stock TBI, I think this idea of losing the reg could really help. That along with raising the injectors must make noticable flow increase. I don't like the JB weld idea though.

 

Check out this regulator cool looking only $39 upto 12 psi
http://store.summitracing.com/produc...earchtype=ecat

 

If you he's only gonna run 13 psi, why modify for increased airflow?

Also, there is an adhesive or filler made especially for aluminum. I believe its called Devcon. Supposedly, it can be drilled, tapped, etc after curing.

The ultimate solution would be to have a drawing made up and have one made out of a piece of alum.

 

I agree with the 13 psi thing would be nice to increase it to 20 psi but I've been unable to find a regulator for a decent price that will go that high. Also you may have to change the pulsewidth going to the injectors so they stay open less at idle speeds. You might be able to go higher on the whole pulse scenerio with higher PSI (faster overall pulse's) or maybe slower. Have not played with that.

If someone knows of a regulator that goes to 20-25 psi for a decent price. What about combining two 9 psi regulators? or will they just adjust themselves to only 9 psi if combined?

Anyone tried using an air pressure regulator for fuel?

 

There are GM TBI regulators capable of going 40+ psi.

Compensation in the code for inceased flow is a given.

What's a decent price?

http://www.jegs.com/cgi-bin/ncommerc...6&prmenbr=361.

Or, you could change the spring in the regulator you mentioned earlier.

 

Some comments, which you can take or leave.

1. The air flow impediment at WOT is the cross sectional area of the throttle bores, so all the stuff you remove or modify above the bores will have only a small effect on maximum airflow. If you want more airflow, you will gain more from boring/sleeving the throttle bores out to a larger diameter. You'll also gain a little bit more air flow by thinning the throttle shaft.

2. Copper feed lines for the fuel will be one of the worst mistakes you could ever make -- so don't do it. Copper tubing is not designed to handle the vibration of an engine -- it will eventually crack open and cause either severe flooding or an engine fire. I do like the idea of replacing the rubber hoses you have with hardline, but it only makes sense to use bendable tubing rated for fluid pressure. Silver sodering it in place, with a suitable flat bracket, would make some sense. This is exactly how GM forms the upper sub-assembly to most fuel pump assemblies: they use steel tubing and they either silver solder (hi temp) or brazing.

3. An alternative to the surgery you performed would be to find a Caddy throttle body (TB, not TBI) from a 500 cid engine. The most recent of them used a 2-bore 670 cfm throttle body that lacked injector pods because they used port fuel injection directly into the intake manifold. The TBI units GM has a more-or-less mirrored from the TB units used by Cadillac.

HTH.

 

Hi,

Tested the jbweld with some solvent overnight and it held up not getting soft or anything. This is the 4 minute setting time stuff with 4 hours full set, but it took overnight to get totally hard.

I've tried using devcon on for some stuff on my saltwater aquarium and the saltwater just ate it up.

I modified the pressure regulator, stupid screw would not come out so I cut into the housing to make a slot in it. I also put a hole in the fuel intake section so I can adjust it while the engine is running. Here's a pic.

 

That would be nice to have an external AFPR. It's a PITA to adjust the regulator in the TBI unit since you have to pull the whole top part off. I can't tell you how many times I've puled it apart on my truck...

 

I'll be testing it tomorrow, went to schucks to get a gasket set and they wanted $39 for it . Since I only needed the pod gasket I made one.

 

Same here, until I modified the regulator. I drilled and tapped the reg for a 1/4" bolt. Drilled out the opening on the TB between the fuel inlet and outlet large enough for the bolt head to pass thru. Now, I can adjust the pressure without disassy. I place a 7/16 wrench right above the vac port for the MAP and adjust away!