My car was running fine until I put a 58mm Throttlebody on it. Now it surges. I expected that it might run lean but I didnt think that when it droped below 2000rpm while rolling it would start to surge. I can visually see the tach jumping like 500rpm up and down and feel it in the car. Also after installing a MSD 6A the tach does some funny stuff after 4000rpm. It like bouces and goes crazy then it shifts and reads correctly again. I am wondering though if the problem with the new throttel body might be cured when I goto a 3.73 rear and keep the rpms up. Anythoughts?

------------------
86 Trans Am 355 TPI Rebuilt 700R4 with Corvette servo, modified valve body, and a B&M Torque Converter (2000 rpm stall w/ lock up), 87 350 block bored .30 with new crank, bearings, rings, and magnafluxed rods. Reworked 305 heads with 3-angle valve job. Added in the rebuild was an SLP TPI cam, BBK 58mm Throttle Body,SVO 24# injectors,MSD 6A, Hypertech Power Coil, 1.5 Crane roller tipped rocker arms, SLP Intake Runners and Port matching in upper intake including fully ported plenum, TPIS adjustable fuel pressure regulator @ 46psi, Hooker shorty style headers w/ Thermotech heat wrapping, Custom 3” exhaust with Flowmaster muffler and chrome quad tips, Hypertech Thermomaster Computer chip, K&N open element cone filter on modified MAF per TPIS specs, MSD Wires, removal of A/C hardware and a 1LE firewall cover installed. Also there has been a PST front suspension kit with Hotchkis strut tower brace
http://geocities.com/SunsetStrip/Garage/9548/kyle.html

Kills:
95 Talon TSI, 96 Probe GT, 91 T/A L98, 89 RS, 86 Mustang GT, 88 Mustang LX 5.0, 92 Thunderbird V8. couple or ricers that I think were Civics or Preludes not sure what year, 95 Celica GT-S, 94 Chevy 1/4 ton 350, one of those NASCAR F150's

 

after installing the tb did you reset the tps and iac?
are you getting any codes?
hows your o2 sensor?

 

Your MSD needs a tach adapter 25 bucks

 

I don't know how to reset the TPS. I have it turned back a little to prevent it from going lean. All though I have not taken a voltage reading off of it. I didn't know there was a such thing a resetting it. Now I have reset the computer by leaving the batter cable off for a week while I was at school. And the IAC. How do you rteset that? Would that effect the performance at like say 1/8th throttle doing about 35mph on a slight incline, becvause my car does not like that either unless you give it more than say half throttle, then it runs fine. At WOT it runs great. Anyways any more thoughts?

 

This link should help you to reset your IAC and TPS.
http://www.sc3gfb.org/resources/tps.html

 

I agree with the above statements, when I read your topic line, I knew almost immediately that your TPS setting was probably off.

------------------
"Clear your mind, relax, and float downstream."

 

WOW

 

Actually you might want to follow this when resetting your IAC. The article at the above link does not work.

"Any tweaking of the throttle stop screw will give the ECM fits. The ECM wants to be in control of the idle and is not happy when it can't control it. If the normal learn limits of the ECM are exceeded, they will be reset to nominal, causing an erratic idle. Doing this assumes a working knowledge of your engine, and basic hand tools and an accurate tach are needed (a scan tool is ideal).
The IAC and associated passages need to be clean to work right. Remove the IAC. If the car has significant mileage, it may be dirty. You can clean it using carb cleaner and a small brass brush. At this time also clean the IAC passages in the throttle body. Once clean, install the IAC back in the throttle body and reconnect the IAC wires.

For the ECM to properly control idle, the throttle stop screw must be set for "minimum air". This is a process that sets the idle with the IAC fully extended. To fully extend the IAC, jumper ALDL pins A and B together, and turn the key on, but do not start the car. With the key on, not running, and in diags mode, the ECM will keep trying to fully extend the IAC. After 10 seconds or so, pull the IAC connector off the IAC *before* doing anything else. This will capture the IAC fully extended. Now pull out the jumper in the ALDL, and start the car. Typically the "minimum air" idle speed is in the 400 to 500 RPM range, so you may need the manual for the spec for your model year and engine. Set the idle to spec (if you have no spec, try 450 RPM) using the throttle stop screw. (The engine should be fully warm to do this.) Now shut the engine off and reconnect the IAC wires. The ECM does not 'know' where the IAC present position is, so pull the ECM fuse for 20-30 seconds. (This will cause a complete ECM reset of all learned parameters, including the learned IAC ones.) Then reinstall the ECM fuse. Turn the key on, wait 10 seconds or so, and turn the key back off. This will now reset the IAC to a known key-off "park" position.

Now start the car. The engine should idle properly under control of the ECM. There are some learned values, such as an IAC offset for A/C, etc. that need to be learned, but this will happen under normal driving conditions. But if the idle is now still out of control, you have other problems"

 

Hey dude, with all those mods, have you thought about getting a custom chip? You defintetly need one. You have all this new air flow and different fuel curves and that hypertech chip is restricting your engine from its full potential. Ed Wright Automotive burns new chips for only $300. Thats a steal, I can give you his phone# if you want.

------------------
88'TA 305TPI 330HP, NATURALLY ASPIRATED, PASSES N.J. EMMISIONS. "I AM JUST THAT GOOD"

 

And I burn custom chips for 100 dollars

 

No offense to you Blade, that's great that you can burn chips for cheap prices. Granted I don't know anything at all about burning chips, but I know Ed Wright sets his parameters into the chip on cars that have been dynoed in his shop. I don't know if that has any difference with what you do, but, like I said your the man that can do this and not me. Good luck dude.

 

I want to get a custom chip, but I want to wait till I get heads and an intake manifold first. Then I will get a custom chip and install the 24#ers then. I think It might be the IAC and when I get home in a few weeks I am going to try to fool around with it