K, I bought this TBI unit from the bay. as you can see there isn't a IAC sensor. Am i out of luck and will it work anyways? I'm having a custom chip done for it, so if the ocmputer is a prob, I'm guessing I can fix it within the chip....

also, what connector do I use to connect into the injector harness? Do i need to buy one to splice into the stock wires and plug into the TBI unit?

 

I think the **** for IAC is there, kind of. All i tihnk i need to do if i want to use the IAC is drill and tap where is should be and get a different TPS.... other then that, evertything else looks the same....

 

That looks like a Holley ProJection TBI Unit. No IAC as it comes but the boss is there. You'd have to have a good machine shop get the casting ready for the IAC and get a different TPS sensor as it will hit the IAC as it sits now.

I used that TB unit as is and disable the IAC control opn the PROM as much as I could, just using the Solenoid pictured to kick up the idle when cold... Switch on the dash.

Used it for TBI and MPFI control... It'll work, but not as good as one with IAC. you won't have active idle soeed control. that can be good or bad, depending on how you look at it.

 

i never was happy with my holley 670. I put one on and ran slower *sigh*

 

i ran slower with a 670TBI?!? What mods?

 

I ran 15.22 with just 3.42 gears, open headers and an open element filter.

Then I put on some vortec heads, an LT4 cam, powerplus carb intake and a 670

take it to the track and it clicks off a blistering 17.5 hmmmm

I got pissed, came home, put my old tbi and injectors on and i could immediatly tell the difference. I even kept up with an LT1 firebird (ok he beat me by a little). But before then he bent me over and raped me so it was a huge improvement. It would also foul plugs, idle poorly, cut my gas mileage almost in half, but most important is that it added almost 2 and 1/2 seconds to my 1/4.

this Holley tbi is BS. Mabye I just got a dud.

 

did you do a chip in all those mods??? or mess with teh fuel pressure???? or play with teh base timing?????
how many runs did you get on the new set up????
just seeing something not work right away and getting rid of it is not how a car gets to 100% performance. you gotta do tuning for a long time to even get an idea of where 100% really is.
teh holley tb is a great thign to have if you plan to upgrade your engine for serious performance.

later
tim

 

i say BAH to the holley ... if anyone wants to buy mine i will negotiate a good price. I tried EVERYTHING with it. I played with FP I used the stock GM with stock injectors, I tried #65 injectors, I tried the Holley ones (unsure of #), I played with MAP pickup placement, TPS, Different MAT placement combinations, messed with the timing for HOURS on deserted roads, even had my dad (GM master tech for 27 years) look at it and he couldnt figure it out, spent hours and got burned alot having to clean the spark plugs. NOTHING worked.

Comparison

Holley:
Fouled plugs
Slow
1 1/4 TANKS of gas to go from here to austin (300 miles)
Blew smoke on startup because of the FP
ran lean up top (too much CFM i guess)
Bogged of the line
effective but weak powerband from about 2500-4000
Dirty oil because of too much fuel
Exhaust fumes that will kill you if you arnt moving
trying to run less rich and putting in 305 injectors results in lean backfires.
#65 injectors are too rich
I had to modify the linkage bracket just so it would work
the adjustable TPS isnt necessary and is pretty stupid
Failed an inspection because they said it wasnt running clean (didnt even hook it up to any equipment, just went by smell)
when all the way closed the throttle blades would jam in the bores

Stock TBI:
a little less than 3/4 tank to go from here to Austin
Clean plugs
Passed inspection YAY
Power band from 1500 to about 5500
Peak around 2700
Doesnt backfire
Runs probably a good 3 seconds faster in the 1/4
no eye-searing exhaust gas
idles without surging or stalling
NO BOG OFF THE LINE! grrrrr (2.9 60' times RULE)
TPS that agrees with the computer
my 2nd gear scratch isnt a chirp its a screeeeech

Anyone wanna buy my Holley can Email me at wickedcamaro@yahoo.com ... I can give you a good price because i picked up the 670 for free from my brother. sooooo
Mabye you will have better luck than i did

 

teh holley tps is set where your stocker shoudl be form teh factory, so anything you did with that was prolly onl;y complicating your probs. i didn't see any mention of data logging or anything when you were messign with it. did you just use teh sight/sound/smell method or what? even at that you shoudl have been able to get the car drivable and more powerful than with teh stock tb.
you woudl be well served to get a hodl of a laptop for a few days and a copy of win aldl and try the holley again. you will be happy you did in the end, even if it is more work right now.

later
tim

 

There is nothing else I could have possibly done. Ok, so i'll have the data showing that its running crappy, that doesnt help. I'm taking it to the track sunday, and im confident of a sub 14.5 run. I've been in lots of low 14 seconds cars and they feel about like mine does.

I still think the 670 is just too much for a mild 305

 

cam, heads, adn intake is mild? i am sure a holley is too much for a stock motor, but once you have that kind of modding into an engien you can certainly use mroe than the stock tb.
data logging woudl have shown you where and when exactly the stock fuel and timing maps were having trouble. that i svery useful when trying to tune a car. if you have not put a lot fo time into tunign the old fashioned way with plug cuts and hearing things it is very very difficult. datalogging is also the basis for a proper custom chip. which si the only way to get peak performance from all of your mods anyway.
it sounds liek you ddi a good job picking parts that will work very well together adn then gave up before you really got teh chance to take advantage.
we spend a lot fo time on this board talkin about the importance of tuning a combo. there really isn't anything otu there in a box that you can slap on and go as fast as teh combo can possible go. that is why everyone needs to take the steps to make sure they pick good parts liek you did and then follow through with the tunign of the new package.
the reason tunign becomes easier with teh smaller tb is because you are dealing with a smaller tuning range. you don't have to adjust as much to get a noticable result because teh tb is keeping a large portion of the useful air out fo the engine.

later
tim