tbi spacer

I'm looking into putting a throttle body spacer in has anybody done This? Who did you use and what were your results.

The throttle body adds a little to the plenum of the intake, and lowers the harmonic frequency of the intake system. The left and right sides are different to begin with, because one side goes under the other, and has a lower frequency than the other to begin with (I think the passenger's side goes under the driver's side). By lowering the harmonic frequency, the compressed charge will get to the valve at a little lower RPM, and the torque curve will reflect that by showing up at a slightly lower RPM. The actual torque will not increase noticeably, and your HP will not change noticeably either, you will just feel it a little sooner. To figure out the RPM it will affect, you have to determine the frequency of the intake, and determine which pressure wave will arrive at the valve when it opens, giving you the RPM when the charge will help the engine. It may be as much as 300 RPM lower.

Another change you can make is to put an extra gasket under the injector tower to open up the airflow through the TBI.

Removing the air injection pump and rerouting your fan belt can remove some parasitic drag. 

One of the best HP per dollar increases you can get is a set of headers and dual exhausts. You can pick up about 30 HP without any other mods. You can get a muffler hanger from the right side of any TBI car, and bolt it to the driver's side (the holes are already there). If you are going to use full length pipes, you need the heatshields from an LT1 car for the tank, or use header wrap on the pipes. I also wrapped the headers to avoid melting wiring, and the ignition wires (plug caps). You will have to make a few other mods, but the cost to install in minimal.

Any intake improvments to be made to add power? Edelbrock,Holley?

The OEM TBI is sufficient to handle the HP/air flow produced/needed by the LO5. To get more HP, you have your work cut out for you. You have to get the air in and out of the heads, and get rid of the gasses too. To flow more air, you need a bigger cam and better flowing manifolds and heads. At the point where you start doing all of this to an LO5, you would better spend your money on an 5.3 or 6.0 LS series engine like an LQ4. The cost if you do it yourself will be a little more, but you will get almost three times the HP/$ for your hard earned dollars.

For about $800 (plus your labor) you can get about 250HP from an LO5. To buy an LQ4 (or a 5.3L) at a pick and pull yard with all the wiring, computer, and 4L60E trans will cost you about $1000. With the LQ4 you get about 325HP and all you have to do is install it with a few mods and parts. Instructions, and parts lists are on the forum. You could use a Y pipe, and make it have a single exhaust, or go to headers and duals.

Either way the engine is coming out to work on it. There really aren't any easy bolt-ons that will give you any substantial HP gains with an LO5. The cam and heads are the big stumbling blocks to making HP with the LO5. If you do change the heads and cam, you need to have a chip burned specifically for those mods at an additional cost.

sorry for the late reply working a lot hours at the lumber mill the headers and exhaust seem like they'd be a better fit for what I'm looking for I appreciate all the information and it's given me a lot to think on