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85 Engine project: The break-in phase

Go with the 383, Not a lot more H.P. BUT ALOT MORE TORQUE!!!!!!!!! YOU WILL LOVE THE TORQUE!!!!!!!!!! Ive owned both 355& 383 THE 383 is MUCH more fun I THINK AW, I know AW , Sorry just kidding ;LOL
 
Its been awhile ....
The vette came out for its longest period of use since I finished it a year ago. My truck tranny had some probs so I drove the vette for main transportation for about 3 weeks ...its now back in the garage . Man what a ride!! it performs better then I anticipated and is still almost scary....lol...but I still have the high idle situation....IAC ...closed and unplugged , throttle blades messaged and ok...no codes ...MAF ok. Ken mentioned a he had his tps tab hanging up a little which sends me on another search....I still believe its going to be something minor.....
Here's a run down on my mods.
L98 block
stroked to 383
6" rods
oliver 4bolt main caps
AFR 195 alum heads P&P
TPIS BiG Mouth manifold
TPIS big runners
re worked plenum
58 m throttle body
roller rockers 1.5
TPIS coated headers
air pump eliminater
TPIS stage 5 chip
MSD wires
stock distributor
accell 24lb injectors
4+3
rebuilt suspension all poly
new u-joints & bearings
new steering rack
 
Well maybe I have something here , I removed my TB and noticed it was rubbing pretty hard on the bore. Could it be my High idle problem . I have massaged it once before and my throttle cable is loose when closed. Is there any reason I cant work this untill it closes further or is this not going to help? there is still clearence for the tps to go back more.it a TPIS 58mm
 
Do the blades appear to be fully closed Dave? They shouldn't rub on the bores, but if they're closing fully it should be okay. There's no carbon build-up yet is there?

Just as a thought, have you checked your idle stop screw to be sure it's not too far open? Have you set the idle speed according to the instructions, from either TPiS or the factory manual?

The throttle position sensor (TPS) is used to send signals to the ECM when accelerating, similar to an accelerator pump in a carburetor. It won't affect the idle speed. ;)
 
Are the blades closed all the way?? should they be straight up and down or slightly tilted . There are gaps around the blades, they dont close tight.The idle screw is not touching it is backed off. I realize there is a setting for this but that just makes it worse.
 
no carbon , clean. The blades fit tight at the top and bottom of the bore, about 1" in length and there are gaps around the rest of blade.
 
Well, your images when viewed individually are no larger than the thumbnails Dave; I can't quite see anything.

It seems strange that you would see gaps at the sides. I have a feeling it's just the way you're viewing it that causes the appearance of a gap. If the top and bottom seal, the sides should as well - the bores couldn't get elongated like that without squashing the whole thing. :L

It seems like you may not have a problem with the throttle body if you can be sure the blades are fully closing. Have you checked for vacuum leaks?
 
I know what your saying, the the blades dont seem out of round , I viewed it from all angles. The bores could be out of round though.I looked at my old stock 48mm and there is lots of light around them blades. hell I dont know. I'll keep digging...... thanks Ken
No vacuum leaks that I have found as of yet....and man have I checked and checked and.......
 
My bet is the blades are hanging in the bores. If the blades unscrew from the shaft you will wanna take em off and take some triple 0 steel woll to the sides and see if ya can make em free in the bore. just my .02


:beer
 
Moe Jr, I appreciate your 2 cents ...it is exactly what I just finished doing . using the idle adjusting screw as a guide i was able to turn in about an 1/8 of an inch after I massaged the blade and touchup the bore. The I just kept lightly filing the blades until they were free and the kinda blended the bore to be uniform all the way around . I realy think its going to work. Wont know until I get it back together. But I'm confident.I hate to admit , but its taken me way to long to take care of this . Overly cautious I guess. Thanks again,
Dave
I cant wait to get that nice lumpy idle back:)
 
The car is back together....no fricken change!!! 1400 rpm in closed loop. I give up....havent a clue...and to think , this was a nice , stock , good running car , but OH NO!!! I had to f**k with it!!!
I did find one thing, the knock senser plug and connector are broken. no codes, the pin on the senser moves around , cant be good.
 
As long as you ain't knockin' ya don't need it anyway Dave. :L (Literally - mine is disabled until we get the rest sorted out. ;)

Sorry man, I know what you're going through, but the rewards will be worth it. Soon you'll have it all sorted out and be able to relax awhile before you start into another project. :v
 
I know you are frustrated Max but it will sort it out. When you have a computer controlled car and you get passed the simple bolt ons and cam changes you will encounter these problems almost always. You are taking a car with thousands of hours of R&D time from GM and trying to remake the whole thing. I gotta tell ya it is this alone that keeps me in check when doing a computer car. I went to the local Chevy dealer once and was talking to one of the service writers I know and I asked how business was. He said was good and at the time they had like 6 C4 Vettes in that were running bad after the owners had put in custom chips. He said 1 thing that has stuck with me and it was "Who do you think has more R&D time and money? GM or the aftermarket tuner companies". I use those words alot sometimes with my customers when I feel they are getting too wild in their ideas. Just my .02


:beer
 
I know what you are saying , both of you and I appreciate it......:confused

Thanks guys
 
I have this new Holly 830 hp in the box setting here and a torker manifold.....hmmmmm
 
The 67 was all original 396/350hp 4sp....blinker tach ....The 68 was not all stock with a big block and the 69 was way not stock , 454 with lots of stuff
 

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