TOPIC: TBI Testing and Information

Last thing I do is check warping of the base. If I find low spots I block the base on my flat machined surface. Here you can see the high and low spots before and after.

After review the Idle air pathway mod. I came up with my own bolt in version that fits both TBI casting.

I"m working on getting my truck read for my state smog check. Then will be bolting on the gadgetman groove. Any tips or adjustments I need to reach the proper adjustments for tbi set up would be a great help. Here is a pic of the test truck I will be using. 89 3500 4X4 Chevy truck 350 E3 plugs K&N air filter. The chip is modded but for other reason It allready run wery well no codes leaks to date. but will check to make sure.

Looks great keep up the good work.

Hi Craig,

As far as the TBi itself, I would think there would be nothing different... bolt it on, hook it up, set the idle...

Your second picture it looks like a hose coming off the valve cover on the right, is that the PCV or just a secondary vent going to the air filter?

If it is just a vent, where is the PCV hose connecting to or have you already moved that to the intake side?

Karl

Karl,
The tube you are looking at is the crank case vent. Goes from the valve cover to a 1 inch spacer that sets on top of the tbi, then the air cleaner sets on top of that. The pcv valve is on the left front valve cover which you can't see from this picture.

Craig

Craig, The idle air mod looks neat. Does it allow any air to bypass? Be sure the idle adjustment screw cap is removed before you install the throttle body. I drill a hole in the center and pry it out with a punch. That needs to be available to adjust the idle so the truck will run. I have a lot of TBI/Groove experience...feel free to give me a call if you need a quick answer. Once you get this done, we will discuss extending the MAP connection further into the intake. Nick 607.590.0391

Nick,
Yes I took the info from the idle air pathway change and made the piece you see. I do need to talk about this at some point. I have a better design but will need more info later on. The test tbi factory idle cap was removed.

Craig

Here is what I have to start my testing. Obd1-2 scanner and the digital timing light!

As I start collecting data one thing one has to rememeber is the condition of the car or truck your working on. The testing equipment in that test. I'm using two scanners a Auto X-Ray EZLink and a newer Actron CP9185 both do obd1-2. The newer scanner when hook up and scanning runs the Idle up an extra 100-200 rpm's I down load new updated software which helped so now it only idling 100rpm higher. All the data looks the same from both scanners at the same rpm's so I will keep using it to print my data out.
First up we did a idle test with the two scanners recording a run cycle about 20seconds long at normal operating temp of 195. A driving test 45 mph and a freeway test at 65 mph. With this data we know the truck is running normal show no codes. On to smog testing next!

Craig

Here are my before Emission numbers done today.

Craig

Remember the only thing that was done was a oil change. cap rotor and plugs are three years old.

Craig