1st time @ track, lots of knock:(

silentbutdeadly said:
in an earlier post he said his 02 was 700ish at idle. shouldnt they bounce or cycle between 0-800-0 when not in throttle. During a WOT blast or at least part throttle doesnt the chip tell the ecm to let the 02 dictate fueling in open loop or is it closed loop i dont remember as i am new at this stuff still. If the scanmaster reads a constant 700ish at idle then i beleive that the 02 is bad.
Click to expand...


tt chips are openloop idle all the time so no the o2s wont flip flop rich lean at idle , crosscounts will hold steady as will the O2 MV except for a breif moment every so often when the chip comes out of open loop to take a peek and make a small adjustment if nescessary (watch the little blinking dot on the SM display for when it flips from open to closed loop then back again )


and yes you need a shroud , with the shroud you get ambeint air to cool the intake charge, without it the radiator is making your intercooler into a interheater and thats not good for trying to make boost without detonation
 
pacecarta said:
tt chips are openloop idle all the time so no the o2s wont flip flop rich lean at idle
Click to expand...

My MV's go from 450's sometimes high 300's to 560's maybe low 600's at Idle. I have a TT Chip.
If I went with a larger 236/230 cam then Eric could make it run in closed loop so the overlap wouldn't send mixed signals to the oxygen sensor.
 
underboost,i am well aware he is running 14psi of boost,however when the car goes to acceleration mode the motor is moving around which has a cascade effect on lots of parts including the knock sensor.and if he is knocking on the big end with 02's in the 800's no matter what his boost gauge reads he needs octane/or better cooling.perhaps his boost gauge is off a little and he's really boosting to 18psi.it's tough to trust and keep working these 20 year old parts, but the knock has to go.easy way to find out,lower the boost or add octane if the knock goes away problem solved.
 
Underboost said:
My MV's go from 450's sometimes high 300's to 560's maybe low 600's at Idle. I have a TT Chip.
If I went with a larger 236/230 cam then Eric could make it run in closed loop so the overlap wouldn't send mixed signals to the oxygen sensor.
Click to expand...

std O2 sensors needs to have heat in exhaust in the 600* range to become fully active , until it reaches that temp it will produce less MV than actual .
with modified exhausts (larger DP , catbacks ,test pipes) and larger turbos its hard to get that required temp especially with a 750rpm idle chip , if you monitor egt you may notice idle temps only in the 500* range ,
run a heated O2 and youll probably find the o2s will read higher ,
 
pacecarta said:
std O2 sensors needs to have heat in exhaust in the 600* range to become fully active , until it reaches that temp it will produce less MV than actual .
with modified exhausts (larger DP , catbacks ,test pipes) and larger turbos its hard to get that required temp especially with a 750rpm idle chip , if you monitor egt you may notice idle temps only in the 500* range ,
run a heated O2 and youll probably find the o2s will read higher ,
Click to expand...

Speaking of catback exhausts, mine lacks one:( I ordered the O2 today @ work, have to wait until tomorrow to get it. Then we'll see whats up with that. I think Im gonna make a shroud this weekend for the IC, the GN one I got seems to be a little too big:mad: I will also probably order the Duttweiler neck from a Vendor too.
 
cabech984 said:
..... I will also probably order the Duttweiler neck from a Vendor too.
Click to expand...

I have a dutt neck intercooler (no shroud... need to keep it for my stock one)I need to move... minimize downtime....I am putting on a stretch 23 row... and won't need mine. I'd like $200 shipped for mine in case you might want to go that route.
 
Id be interested in the intercooler, but I got this one here and got a welder(wannabee) as a brother so I'll probably save the bucks and do it this way. Thanks though!!!

I drove a little more tonight waiting for my new GNX O2. A fifteen minute trip to the post office. I didnt get on it at all so I dont have WOT 02 numbers or knock numbers.

02's 742-761 (30 seconds, didnt go lower or higher)
AF 05
L8 36-37
bat 13.3
int 128
bL 132
clt 182
ats 119
rpm 825-850
tps .42
IAC 14
cc stayed at 249

The 02 seems to cross count fine @ cruising speeds, nothing @ idle.
 
Make sure you have all the right stuff... I think it is aluminum tanks....

Aluminum welding is not for everybody... and you have to have the right equipment.....

Whether or not you buy my dutt neck intercooler makes no difference... but at least consult with someone locally that does weld aluminum....
 
Think I found the problem. I installed the GNX O2 sensor today, seems to be much more active than my Bosch was. So, I reset the ECM and Fuel pressure(43psi) It was dark out and was making a fuel pressure adjustment and I notice that I can see spark jumping from the metal boot cover to the cylinder head. Im letting it cool down now, and am gonna get those fixed. I saw 5 degrees of knock today after resetting and driving around for about 10-15 minutes. Hopefully this will fix it!! Speaking of plugs, I have them gapped @ .032". That gap should be adequate right?
 
cabech984 said:
Think I found the problem. I installed the GNX O2 sensor today, seems to be much more active than my Bosch was. So, I reset the ECM and Fuel pressure(43psi) It was dark out and was making a fuel pressure adjustment and I notice that I can see spark jumping from the metal boot cover to the cylinder head. Im letting it cool down now, and am gonna get those fixed. I saw 5 degrees of knock today after resetting and driving around for about 10-15 minutes. Hopefully this will fix it!! Speaking of plugs, I have them gapped @ .032". That gap should be adequate right?
Click to expand...

Gap them at .28 ;) Plug R43TS Get some good plug wires when you can too. That will help fix the light show :biggrin:
 
Well, I closed the gap to .028-.029 on my autolite 24's. Also noticed some carbon tracking on the number 5 plug, made sure the boots were 100% down. The plugs looked clean & free of oil fuel, etc. Were a brownish color. So I reset fuel psi to 43, reset the chip drove it around for a while for the ECM to learn. Boost @ 15psi, seeing 780-810mV @ wot & 11 degrees of knock. I need to take a video of my engine while revving, the mounts look pretty bad after paying attention to them. I am hearing zero pinging, the pistons looked ok(well the 2 that were visible) Im gonna try the 110 octane now and should fix my problem or determine the false knock.


Ill keep yall posted. Thanks for all the help and guidance and I am definatly not discouraged about this project. I just cant wait to get this beast running w/ zero knock!!! Chris
 
cabech984 said:
Well, I closed the gap to .028-.029 on my autolite 24's. Also noticed some carbon tracking on the number 5 plug, made sure the boots were 100% down. The plugs looked clean & free of oil fuel, etc. Were a brownish color. So I reset fuel psi to 43, reset the chip drove it around for a while for the ECM to learn. Boost @ 15psi, seeing 780-810mV @ wot & 11 degrees of knock. I need to take a video of my engine while revving, the mounts look pretty bad after paying attention to them. I am hearing zero pinging, the pistons looked ok(well the 2 that were visible) Im gonna try the 110 octane now and should fix my problem or determine the false knock.


Ill keep yall posted. Thanks for all the help and guidance and I am definatly not discouraged about this project. I just cant wait to get this beast running w/ zero knock!!! Chris
Click to expand...


Cool:cool:

Are you sure you're getting at true reading on your boost gauge? Have you check all the vacuum lines including underneath the vacuum block? They seam to crack now that there 20yrs old. You're gauge could read 14 but the true boost could be 20. Just an observation. :)
 
Most of the vacuum lines are new, but there are some that I didnt change. I'll check for vacuum leaks tomorrow, what methods do you use to check?? soapy water?

I also have a HKS external wastegate that I bought from a fellow board member, if the spring in that was designed to open @ say 20 lbs, could I still turn the boost controller down so it only read 14?

Also, seems like no matter what I do, I always have 135bLm's @ hot idle. Ive heard that High BLM's are an indicator of a vacuum leak. Wouldnt te vacuum leak cause a high idle?

Chris
 
135 is no reason to be concerned , probably a lot closer than most

temp also has an affect on blm and when the season cools it will swing the other way , thats what the blm stores values for in the first place
and on the HKS or any other gate , the spring is the minimum you can run at WOT , i run a 5psi spring in my HKS gate with an electronic boost controller
 
Well, I didnt get around to checking for vacuum leaks, but I am starting to think that my HKS wastegate has a 20 psi spring in it:eek: I bought new motor mounts today, Advance had them for $21 each(TTA passenger side) Im gonna get some 110 leaded tomorrow and see if that helps. I'll keep you posted
 
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