TBI tuning

[SebasSF]

Sorry no pics, but I took out the spacer that was between my air cleaner assembly and the top of the fuel injector body. This drops the air filter housing down about 2 inches and makes much more space for air to get around the injectors. I cut down the bottom of the post that holds the top of the air filter on, added two washers to get a solid fit, did a couple small tweaks to make it fit flat, put the gasket back in and done. I also installed a Harris Performance Towmaster chip from eBay. Runs really nice with the full Banks system. I did not notice much of a performance difference, but I like the mods. May install a fuel pressure gauge next to check pressure. Also broke off the vertical metal "wall" around part of the intake for better flow...

[92landyacht]

I love it when people do modifications and have no evidence or proof of any benefits. For all you know you've reduced your torque and HP figures in the usable power range. May sound harsh, but it might protect someone else from doing something that has damaging results based on ignorance.

[SebasSF]

Thanks for the heads up. You are correct...nobody should make any modifications to a stock motor without doing their homework. I do however think that a Banks system is an old and proven improvement and Harris Performance really know what they are doing. One of the reasons I am part of this forum is to learn about improvements and modifications people have made to their RVs, and fortunately for people like me there are some really good forums on TBI performance and tuning as well. Chevy left a lot of room for improvement.

[92landyacht]

Agreed that improvements are available. The Banks system is a tried and true method for making improvements. Banks did much research and testing before they marketed a system with verified and measurable results. It was simply the "I did not notice much of a performance difference, but I like the mods." part that made my skin crawl.

[Wayward]

Originally Posted by 92landyacht

I love it when people do modifications

It is cool. Getting out the wrenches and working on our vehicles is the great attraction to engines and drivetrains - part of the experience IMO.

I've learned a lot from dreaming, trying, mistakes, and retrying. There is no optimal extent of engine upgrades. Everything is about tradeoffs.

Starting the project on the work of Banks and Harris is a solid start.

Next step is figuring out why there is no noticeable performance improvement. Maybe it is there and just needs to be measured. There are handheld monitors with GPS and accelerometers that you enter the truck's weight, that can tell you a lot. There are Android and iphone apps too.

You may see an improvement in gas mileage or in the mountains. Who knows

If not, there may be something simple you overlooked that you can figure out based upon the principles that the mods are based on.

Have fun!

[SebasSF]

One thing I can tell you is that the 91 with a Banks system is a huge improvement in performance over the 79 Excalla- I have owned two of them. As far as noticing a performance gain from this small mod- I did not expect to notice it really, on such a large and heavy vehicle.
Ohttp://www.thirdgen.org/techboard/tbi/227281-new-tbi-check-out.html is a great site to start learning about TBI topics.