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Ken's Engine Project...

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I would bet your problem is in the esc (timing portion). It does not get up and running until you hit closed loop. With the heated O2 you are getting there pretty quick eventhough you are not that hot on the engine. You must have a bad setting on your timing.

Here is how to do it for max efficiency.

You need to get a scanner. I like the Actron Brand, but really any brand that has a instant read mode is fine. You will plug it in, and dial it up to your cars, then ask it to show you three different things. You want to see the loop mode, spark advance, and O2 milivolt readings.

Drive the car around until you see closed loop. YOu need a passenger for this and some open stretch of road. When you hit closed loop, you will do some wide open throttle runs. You want to watch the spark advance/retard feature on the scanner. Keep adjusting the ignition timing by turning the distributor foward and backward until you see little to no retard on WOT under a load. You have no use even for a timing light other than to initially start the engine.

Now, watch the O2 reading. You want it to stay under 900, and above 800 at WOT in closed loop under a load. You can adjust this by cranking up and down on the fuel pressure regulator.

This requires a lot of stop and go, open the hood, making adjustments, then going again.

I have a feeling you are running too advanced, and when you hit closed loop, then warm up to where it wants to detonate/spark knock, the timing keeps getting kicked back retarded causing you to loose power or at the least that crisp feeling you get when it is cold.


let me know how this works out.
 
I don't know about the other guy, but Will sounds like a straight-shooter. It's seems that it get harder to find people like that. I guess you'll be recommending him to other rodders, eh Ken? :upthumbs

--Bullitt
 
69MyWay said:
When you hit closed loop, you will do some wide open throttle runs.
...let me know how this works out.

Chris, I followed your suggestion and ran it wide open several times, now it smokes like crazy. Do you think I should have waited until I broke it in first? :L

I'm just kidding of course, but remember that it isn't broken-in yet, so I can't be doing banzai runs. Besides that, I'll need a dragstrip or some kind of racetrack to do that with the exhaust as loud as it is now. :eek

Thanks for the insight though Chris, I DO appreciate the tips. :upthumbs

Bullitt, Will is a stand-up, straight-shootin' kinda guy. I wish I'd have met him years ago, as well as having my late brother meet him, they had a lot in common.

Of course I spread the word, about him and Richie and whoever I feel does a good job and cares about their customers. It's called "Karma" isn't it? ;)

_ken :w
 
Took it to Wagoner's Dyno today and had Jeff put it on a scanner for me. I couldn't retrieve a code at home, but by the time I reached his shop it had set a Code 33, which as you are probably aware is the MAF Sensor or Circuit Too High.

The numbers we saw were pretty screwed up; the Integrator was at 117, the TPS voltage was .60, the Block Learn was at 108, the IAC position was 107, and the MAF was 14 with the airflow at 14 gm/sec.

I talked to Terry at TPIS and he said that the chip is burned for 258 gm/sec airflow, but that I should never see that much flow. He suggested opening the throttle blades a little to help the IAC and to set the TPS a little higher at around .64.

He also said that this is a "common" occurance in that some people develope this problem while others don't. He said that if tweaking doesn't work and we can't solve the problem with a reburn on the chip, the only other option he could think of was to go with a Speed Density system and trash the MAF. Can you say more time, and most of all, MO' MONEY! :mad

As has been said here many times before (although Bud hasn't said it in a while), "You gotta love 'em!" :gap

_ken :w
 
Holy crap!!:eek......Have I gotta learn all that Jargon?........I WANT MY CARB BACK!!!!!...........

Integrator,block learn,qm/sec.....your scarin me again :eek
:L:L
 
I'm with "maxrevs85" all that jargon is over my head. I'm having a slight rich condition problem plus it now doesn't like to start after getting fully warmed up BUT I haven't been able to check things out fully as I have no equipment. Jeff has offered to help so I ordered an adapter from Craig Motes to see if Jeff can make some chip changes after some diagnostic look see. All that's a big IF at this point but chasing down these "charater builders" is what makes it worth while!

Ken - I thought the MAF system would be getting a bit iffy at supporting 500+ HP?

Phil (aka 89ZZ4)
 
Ken said:
Took it to Wagoner's Dyno today and had Jeff put it on a scanner for me. I couldn't retrieve a code at home, but by the time I reached his shop it had set a Code 33, which as you are probably aware is the MAF Sensor or Circuit Too High.

The numbers we saw were pretty screwed up; the Integrator was at 117, the TPS voltage was .60, the Block Learn was at 108, the IAC position was 107, and the MAF was 14 with the airflow at 14 gm/sec.

I talked to Terry at TPIS and he said that the chip is burned for 258 gm/sec airflow, but that I should never see that much flow. He suggested opening the throttle blades a little to help the IAC and to set the TPS a little higher at around .64.

He also said that this is a "common" occurance in that some people develope this problem while others don't. He said that if tweaking doesn't work and we can't solve the problem with a reburn on the chip, the only other option he could think of was to go with a Speed Density system and trash the MAF. Can you say more time, and most of all, MO' MONEY! :mad

As has been said here many times before (although Bud hasn't said it in a while), "You gotta love 'em!" :gap

_ken :w

BLM at 108 :eek you are running way rich!! you have a TPiS prom I assume? it is running the 89 code now since you have a miniram and no 9th injector?

Also is you MAF sensor ported? My guess is some of the MAF tables need to be adjusted to start. Also what size injectors are you running? What is you Fuel Pressure set at with no Vacuum (WOT). I have not been able to completely keep up on all these posts.. But I tell you what will help you get the PROM tuned in..

Get a hold of someone near you with DIACOM or EASE Scanning software.. hook it up to your car and take some readings at Idle and various RPMs while in neutral (no load) Log this data and send it to TPiS along with the PROM to reburn it. Also do some cruising and log the data.. then do some WOT passes and log data. It may take more then one time to send it back to TPiS to get it right. This is just the way it is.. Tuners basically guess what should be right, every car is a little different, so they base it off of experience and knowledge form all the PROMs they do to hope it is dialed in close. Sounds like if you sent TPiS some log files with the PROM they will get it closer.


As for the IAC setting, I understood it as not to exceed 110 so your 107 at idle sounds about right. .60 TPS volts is also okay at idle.. I think .65 is the max you would want. the Integrator is the Short Term fuel, at 117 it is still removing fuel due to the rich condition. the 108 BLM, Long term fuel, is at the limit set in the ECM.

Hope this helps..

Phil, I think we should have no troubles getting your car dialed in and fixing the rich condition you are also seeing.
 
89ZZ4 said:

I thought the MAF system would be getting a bit iffy at supporting 500+ HP?

Phil, You are correct. Basically it is more of an ECM restriction then a MAF restriction. the ECM is only allowed to read from 0-255 due to the programming and configuration of the PROM and ECM. the later MAF cars (94-newer Vettes) are a different set-up with a broader range.

When you port the MAF you will increase the physical flow, but the ECM will only read to 255. that is it.. no more. So when you get a bigger motor sucking more air then the MAF becomes the restriction.

With the 85-89 MAF cars, anything above the 255 can be programmed but it is more of an assumption then actual data.

With the Speed Density set-up it no longer has the MAF restriction but becomes very sensitive to changes. the nice thing is that you can tune this set-up a little more accurate usign direct reading from the car VIA a scan tool
 
Jargon for me to but from what Im getting would a Granatelli MAF sensor help here with the Screen cut out? (Just thinking because it would generate from CFM passage)
 
-=Jeff=- said:
Get a hold of someone near you with DIACOM or EASE Scanning software...

Stuff like that is a ***** when you have no friends.
 
BigRed said:
Jargon for me to but from what Im getting would a Granatelli MAF sensor help here with the Screen cut out? (Just thinking because it would generate from CFM passage)

only if you can find someone to program it for the ECM.. the 85-89 are SOL on aftermarket sensors like Granatelli..
 
Ken said:


Stuff like that is a ***** when you have no friends.

There has got to be SOMEONE on this board that is near you that would possibly be willing to help you out..

If I lived near you I know I would help you out with that
 
Have you had any experience the change-over to a Speed Density system Jeff? If so, can you tell me what is involved?

_ken :w
 
Ken said:
Have you had any experience the change-over to a Speed Density system Jeff? If so, can you tell me what is involved?

_ken :w

I sort of had some experience.. I did a conversion and had my car running but then opted for the dash swap which included it..

This Website is a great resource to help if you convert.. keep in mind though the Fuel AVG, INSTANT Fuel, and range will not work with the Speed density..

Here is the website

http://www.eecis.udel.edu/~davis/z28/
 
:L You neglected to tell me what is involved when performing this conversion.
 
Ken said:
:L You neglected to tell me what is involved when performing this conversion.

OOPS, Sorry phone rang here and I got off track..

As for the conversion you will need to make an adapter to connect the NEW Speed Density ECM gm # 1227730 or 16198262 (These are out of a 1990-1992 F-body mainly) to your existing harness in place of the current ECM.
You will also need a F-Body MEMCAL, AP sensor, and a 1990-later Knock sensor.

The ESC module is no longer needed in your car (it is part of the new MEMCAL) and the MAF will no longer be used. That website shows all the pinouts to do the conversion.

I would offer to assemble one for you but I am not sure when I would get to it.. I have been so busy here I am falling behind on the Conversion for Bigred (doing the 85 to 89 conversion). Hope this helps a little bit.
 
:o Boy is my face red! I failed to notice the link at the bottom of your post and thought that you had forgotten to include it. But it was I that missed it! :o

Basically, your words echoed exactly what Terry at TPIS told me. In that case, not only would I be forking out more money for the SD system, I would have to take yet another hit and write-off the new MAF, the new chip (TPIS might take the wash on that -- I forget what he told me.), and whatever else it takes, and is possible to spend more money on. :eyerole

I knew I should have built a hot rod with a flathead! :L

_ken :w
 
Ken,

Here is what I would do..

Invest in a laptop.. not too much just a basic 386 or 486 or even early pentium to run either DIACOM OR
Craig Moates SOftware (which is Free)
buy the AKM Cable to work with Craig's software and start scanning your car for data to get that 165 ECM you have dialed in..
here is the link for Craig's stuff and the cable

http://ice.prohosting.com/moates/gmecm/software.html
 
Thanks for the info Jeff, I'll be checking into it. It looks like I've got some research to do, eh?

Well, the first piece to quieting my exhaust just arrived.
DSCF0001_0001.JPG


Here's what's inside:
DSCF0002_0001.JPG


Now, if that doesn't do the trick (and I seriously doubt it will), the new sound capsules will be arriving shortly. Hopefully this will allow me to drive it at least.

_ken :w
 
A "printable" version with all posts to this thread would take 155 pages! :L
 
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