I know the general dislike of the Edelbrock TBI intake but it looked like the best choice so I did the swap in time to test it at the track on Fri night.

The install was straight forward, although I had to do some dremel work to clean up the intake ports. In about 3 hours I was up and running.

I wasn't expecting a SOTP difference, but I could tell that throttle response had improved. The track numbers where alright, but nothing huge. My best run was a 15.28 at 89.43 mph. So I gained about a tenth and a half and a mile per hour over my previuos fastest time. My average e.t. did however drop from a 15.51, to a 15.33, so the average time was alot closer to the fastest time (which helped me take home the trophy in Friday night's Street Wars )

I think I could pick up some more time after I do some tuning b/c it is not running quite as smooth as before. I lost a little bit more than half a tenth on my 60 foot time and I could feel a bit of hesitation off idle. If anyone else had this problem and might have a solution let me know!

Everything costs about 250$ which is a little disapointing for a tenth and a half, and a mile an hour.

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1991 Chevy Camaro RS TBI w/auto
Mods:
Edelbrock TES Headers, REALLY high flow cat, 2 1/2 in catback flowmaster, 160 stat, hypertech chip, MSD ignition (rotor, cap, superconduct. wires), Bosch quad4 plugs, Edelbrock TBI Intake, Ram Air Box's twin snorkel, all TBI mods, no smog stuff, no EGR, lots of suspention and alignment upgrades.

Fastest e.t.:
15.42 @ 88.19mph
Fastest 60 foot:
2.113

 

did you turn up your fuel pressure? That's probably the hesitation. Or you need a new chip

------------------
-Tas
'89 Formula WS-6

305, TBI, 700R4, P.A.W. 14x3 open element with K&N, Milodon 160* thermo, functional Formula hood, cross-flow Flowmaster, '99z28 rear pipes and tips, Hooker 1-5/8" 50 state legal headers, Dynomax 3" I pipe (PN 44063 and 43248)
Super GRK_Taz World
F-Body Dual Exaust
EFI & Intake Options

 

Taz is probably right.
Speed density systems like ours (no MAF sensor) have a preset table and AFR under WOT. This isn't a good thing when you start letting the engine breath in more air. Reason being...no MAF means no way for the engine to measure the amount of air to fuel ratio. This is why we have an o2 sensor BUT...that doesn't work under WOT anways since it's far from accurate.
It's like this: There is a BLM...if you run lean after doing some bolt ons your BLMs will be above 128 which means the ecm is adding more fuel. Problem is when you go to WOT the ecm goes to 128! You go lean..hence the hesitation. There is another hesitation and its usually because of the pump shot. Stock pump shot designed for stock TB, stock fuel pressure and stock motor with a crappy air cleaner. High flow and the pump shot will be far from accurate hence another hesitation. Your best bet would be to adjust your fuel pressure. Don't turn it too much, probably only need a 1/4 to half turn.

 

I'm running 12 psi now and I have a Hypertech chip (which probably doesn't do much).

I've heard that if you put resistors in the Coolent temp sensor and the Air temp sensor you can richen the mixture b/c the computer beleives that the car hasn't warmed up. I've used a 680 ohlm resistor for the coolent which worked in the summer, but with the colder weather I seem to run a bit slower when I use it.

I think I heard that Tas put to together a table of resisters that worked for different temps...anyone got the website?

If I have upped my fuel pressure, what else could be causing my hesitation/rough running idle?

 

Wouldn't that coolant temperature sensor change make the computer run in open loop all the time? Wouldn't this (even tho running richer) slow you down even more, even at WOT? I'm not asking rhetorically, I'm still trying to learn. My impression was that closed loop timing and all would be better than open as long as you have decent fuel pressure.

 

As far as I know when you are in WOT the computer goes into open loop anyway.

 

Tas and Jon are both right, you need to bump up your fuel pressure. I had your same problem when I put on my edelbrock tbi manifold. Well, wasnt actually a problem, idle was acceptable and I only got a small shudder when taking my foot off the brake and lightly tapping the gas. I use bigger injectors now anyway, so I certainly don't have that problem anymore, now I cant get the pressure low enough for decent sniffer readings. If I were you I wouldn't go trying to fool the computer with resistors, just give the PR about 1psi or just deal with the bumpy idle. If you're racing the car, you're going to have the car idling at least at 1000rpm before takeoff amyway, so it will be past that point of hesitation.