396 LT4 Stroker Tune
Thread Starter
Racer
Joined: May 2013
Posts: 278
Likes: 7
From: Long Valley NJ
396 LT4 Stroker Tune
So long story short: I transplanted an LT4 stroker in my 95 over the winter. No expense was spared - anything that was encountered not up to snuff was replaced. And then some.
I can not seem to get the excess fuel out of this car. It's ridiculously rich. I have no DTCs (they've been trouble shot and parts replaced....out). This car fires clean with no codes instantly. It's snappy as sh*t. But it is crazy rich - and it's almost caught cats on fire twice, which tomorrow - are now getting cut out...just so I can tune it.
Anyone want to get a look at the tune? I've been working with someone who has an excellent rep, but he's not getting me anywhere. This car is not running ANYWHERE near it should be.
You would need datamaster to get a look.
Let me know and the help is appreciated (and rewarded).
Thanks, guys.
I can not seem to get the excess fuel out of this car. It's ridiculously rich. I have no DTCs (they've been trouble shot and parts replaced....out). This car fires clean with no codes instantly. It's snappy as sh*t. But it is crazy rich - and it's almost caught cats on fire twice, which tomorrow - are now getting cut out...just so I can tune it.
Anyone want to get a look at the tune? I've been working with someone who has an excellent rep, but he's not getting me anywhere. This car is not running ANYWHERE near it should be.
You would need datamaster to get a look.
Let me know and the help is appreciated (and rewarded).
Thanks, guys.
Last edited by Drew95; Jun 11, 2015 at 08:34 PM.
Thread Starter
Racer
Joined: May 2013
Posts: 278
Likes: 7
From: Long Valley NJ
Thanks, Frank - Here's the last couple logs (3) under the the SAME tune.
I can send/post the tune file as well.
I still haven't got the car back from the shop yet where they're cutting the cats out and putting (Corsa) resonators back in, but I doubt that is going to matter much.
Let me know your thoughts - really appreciate your feedback and you taking a look. Thank you!
I can send/post the tune file as well.
I still haven't got the car back from the shop yet where they're cutting the cats out and putting (Corsa) resonators back in, but I doubt that is going to matter much.
Let me know your thoughts - really appreciate your feedback and you taking a look. Thank you!
Burning Brakes
Joined: Mar 2005
Posts: 1,082
Likes: 115
From: Richmond Hill Ontario
had a quick look at some of the logs. Looks like you should close your throttle blades somewhat via idle setscrew. Reason is that your idle is at about 1050 rpm and your IAC is at zero. You want to close your throttle blades a bit so that your IAC sits at about 40. This will also mean that you would need to adjust your TPS so it reads about 0.50volts.
Also, seems that on one of the logs your speed was only registering a max of 3mph, not sure if something is wrong here. In this log it shows that you are only using 4 BLM cells. In my opinion seems that the tune needs to have the "BLM RPM BOUNDARY" and " BLM MAP BOUNDARY" adjusted. This would help out a lot when in closed loop.
I'll spend some more time reviewing the logs tonight.
If you want to send a new log that would be great.
Also, seems that on one of the logs your speed was only registering a max of 3mph, not sure if something is wrong here. In this log it shows that you are only using 4 BLM cells. In my opinion seems that the tune needs to have the "BLM RPM BOUNDARY" and " BLM MAP BOUNDARY" adjusted. This would help out a lot when in closed loop.
I'll spend some more time reviewing the logs tonight.
If you want to send a new log that would be great.
Thread Starter
Racer
Joined: May 2013
Posts: 278
Likes: 7
From: Long Valley NJ
Roger that. I'm a little backed up on work, so won't be able to adjust/log until Saturday but this is good stuff and easy enough to tweak.
As far as speed, disgregard what you see in logs. I should've mentioned - the gears in there now don't match the speedo set and it's just as well because I"m probably not going to keep them.
Thanks - Frank. Get back to you this weekend.
As far as speed, disgregard what you see in logs. I should've mentioned - the gears in there now don't match the speedo set and it's just as well because I"m probably not going to keep them.
Thanks - Frank. Get back to you this weekend.
Thread Starter
Racer
Joined: May 2013
Posts: 278
Likes: 7
From: Long Valley NJ
Backed up the TB blade...idle now averaging around 900ish. I can't go any further....she'll stall. This cam has some lope at 110 LSA so that's as far as I could.
See attached idle log. I gave it two snaps and a gradual "up". Also, for some reason now, I keep losing connection for a few seconds on Datamaster, than it re-establishes.....
Anyway, the "richness" condition is probably now worse. It's unbelievable how bad the car smells after logging this.
Like...knocking birds out of the sky...bad.
The TPS voltage seems to see around .3 which I'm told is fine....as long as between .3 and 1.0, I'll always read 0. The IAC position is showing way under 40 now.
I don't think this is a setup issue. I've done leak down tests 5 times...I hold 40 pounds all night.
This log has brand new oil and new plugs. I'm spending a fortune dumping/replenishing gassy oil trying to tune, here.
I need to get gas OUT of this tune. It's WAY too much. VE, or timing or something else has to be the culprit. If you could smell (taste this), you'd get it. I just don't know how to get it out.
See attached idle log. I gave it two snaps and a gradual "up". Also, for some reason now, I keep losing connection for a few seconds on Datamaster, than it re-establishes.....
Anyway, the "richness" condition is probably now worse. It's unbelievable how bad the car smells after logging this.
Like...knocking birds out of the sky...bad.
The TPS voltage seems to see around .3 which I'm told is fine....as long as between .3 and 1.0, I'll always read 0. The IAC position is showing way under 40 now.
I don't think this is a setup issue. I've done leak down tests 5 times...I hold 40 pounds all night.
This log has brand new oil and new plugs. I'm spending a fortune dumping/replenishing gassy oil trying to tune, here.
I need to get gas OUT of this tune. It's WAY too much. VE, or timing or something else has to be the culprit. If you could smell (taste this), you'd get it. I just don't know how to get it out.
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Thread Starter
Racer
Joined: May 2013
Posts: 278
Likes: 7
From: Long Valley NJ
Did ANOTHER leakdown test....
41 lb at key on.
1 Hour later, down to 31lb.
Injectors are 42lb greens...if I didn't mention....
*Edit - 20lbs now. So, dropping 10lbs an hour. If that signifies a leak in the fuel system, let me know thoughts.
Thanks, guys.
41 lb at key on.
1 Hour later, down to 31lb.
Injectors are 42lb greens...if I didn't mention....
*Edit - 20lbs now. So, dropping 10lbs an hour. If that signifies a leak in the fuel system, let me know thoughts.
Thanks, guys.
Last edited by Drew95; Jun 14, 2015 at 06:06 PM.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The IAC count reflects how much air is getting into the engine. The ECM uses the IAC to control the idle speed. You need enough margin to allow the ECM to work. If you're at or near zero then you have a vacuum leak and the ECM is trying to compensate by closing the IAC (closed loop of course).
Thread Starter
Racer
Joined: May 2013
Posts: 278
Likes: 7
From: Long Valley NJ
-
Thread Starter
Racer
Joined: May 2013
Posts: 278
Likes: 7
From: Long Valley NJ
New log with your tune applied. This one is 3x the size of the one from yesterday....
Also - YES on your last PM (re: TUNERCATS). Consider it done, my friend.
Let me know your thoughts on the log.
Also - YES on your last PM (re: TUNERCATS). Consider it done, my friend.
Let me know your thoughts on the log.
Thread Starter
Racer
Joined: May 2013
Posts: 278
Likes: 7
From: Long Valley NJ
The TPS voltage should be 0.54 volts at idle for 0% throttle opening.
The IAC count reflects how much air is getting into the engine. The ECM uses the IAC to control the idle speed. You need enough margin to allow the ECM to work. If you're at or near zero then you have a vacuum leak and the ECM is trying to compensate by closing the IAC (closed loop of course).
The IAC count reflects how much air is getting into the engine. The ECM uses the IAC to control the idle speed. You need enough margin to allow the ECM to work. If you're at or near zero then you have a vacuum leak and the ECM is trying to compensate by closing the IAC (closed loop of course).
There's no vaccum leaks. This is also not even close to a stock motor.
I am, however, running a stock 95 PCM.
What're you thinking? I'm guessing there's something bothering you about setup...
How would I even adjust voltage? I have an AS&M 58mm Monoblade....
TPS just screws in...there's no pots and I don't see squat in the tables... I have a blade adjustment screw...that's it.
Last edited by Drew95; Jun 19, 2015 at 08:46 AM.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Thanks for chiming in, Cliff!
There's no vaccum leaks. This is also not even close to a stock motor.
I am running a stock 95 PCM.
What're you thinking? I'm guessing there's something bothering you about setup...
How would I even adjust voltage? I have an AS&M 58mm Monoblade....
TPS just screws in...there's no pots and I don't see squat in the tables... I have a blade adjustment screw...that's it.
There's no vaccum leaks. This is also not even close to a stock motor.
I am running a stock 95 PCM.
What're you thinking? I'm guessing there's something bothering you about setup...
How would I even adjust voltage? I have an AS&M 58mm Monoblade....
TPS just screws in...there's no pots and I don't see squat in the tables... I have a blade adjustment screw...that's it.
The comments about IAC still apply, though. If the counts are close to zero then you have extra air getting into the engine and the PCM is trying to compensate.
