SDCE & Belt Slip
Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
Originally Posted by kp
you dont happen to have any log files from the dyno or track do you?
Does your boost seem to vary a lot? Are you just looking at the gauge or do you have a peak/hold gauge or are you logging it somehow?
Does your boost seem to vary a lot? Are you just looking at the gauge or do you have a peak/hold gauge or are you logging it somehow?
dyno looks OK, heavy car like that could use a little more gear at the track though. I would put a decent wideband in the car, it looks like you may be a little rich there and even with 91 you should be able to ru a little more timing with that amount of boost, especially at lower RPM.
post up the log from the dragstrip video you posted if you can
post up the log from the dragstrip video you posted if you can
Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
I thught 11:1 - 11:5 was fine for FI? I know I gained 30 rwhp when it was up to 12:1
I had the timing up to 20 with no knock. But no increase in HP up top. So backed it down. Next time I am on the dyno, I will do what I always do. Start the timing @ 20* then ramping it down by 6500.
I had the timing up to 20 with no knock. But no increase in HP up top. So backed it down. Next time I am on the dyno, I will do what I always do. Start the timing @ 20* then ramping it down by 6500.
Last edited by Ed Blown Vert; Oct 18, 2005 at 11:42 AM.
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Verdad Gallardo you can probably start the timing a little higher then 20, peak horsepower on the dyno and getting a heavy car moving at a dragstrip is two different things 
I would keep the timing around 25 under 4500 and start ramping down from there but thats just me.
Well, I run 12.5:1 a/f or so at the track, 11.5 will slow me down quite a bit. I really dont trust dynojet widebands, if they arent maintained they will read all over the place. Every combo will react to timing and a/f a little different, 11.5:1 is very 'safe' but will also cost power - dont be afraid to experiment a little with things on the dyno. I dont even bother much with the dyno anymore, with the wideband in the car I do all my tuning at the track
I would keep the timing around 25 under 4500 and start ramping down from there but thats just me.Well, I run 12.5:1 a/f or so at the track, 11.5 will slow me down quite a bit. I really dont trust dynojet widebands, if they arent maintained they will read all over the place. Every combo will react to timing and a/f a little different, 11.5:1 is very 'safe' but will also cost power - dont be afraid to experiment a little with things on the dyno. I dont even bother much with the dyno anymore, with the wideband in the car I do all my tuning at the track
Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
I'll most likely go back to ramping down on the timing.
I would like to run 12:1, like I said gained me over 30 rwhp.
Even with that AF and 20* of timing I had no knock on the dyno.
I thought 12:5 was very unsafe? I guess if there is no knock your fine. Just kinda contradicts most everything I have read here.
But I have been thinking about getting a WB and doing more tuning at the the track. Thats where it counts.
I would like to run 12:1, like I said gained me over 30 rwhp.
Even with that AF and 20* of timing I had no knock on the dyno.
I thought 12:5 was very unsafe? I guess if there is no knock your fine. Just kinda contradicts most everything I have read here.
But I have been thinking about getting a WB and doing more tuning at the the track. Thats where it counts.
another thing is your IATs are way up there at the track, that will cost you big time power. Try not to let the car run for a long time and vent your bypass to atmosphere so its not jamming all that warm air back into the inlet. If I make 2 back to back dyno pulls and my IAT is over 150 I lose 50-60rwhp. You can use your IAT table to pull some timing at the top end of the track as well, it spends more time at higher RPM in high gear so a little timing out on the top of 3rd gear wont hurt. Here is a 9.7x @ 138 pass, its a little lean but the temp was cooling off quicker then I could compensate - didnt blow up though But this is the a/f going down the track, not on a dynojet you have to remember. I dont want you to blow your car up, take it easy and a step at a time but you have more power there..
But this is the a/f going down the track, not on a dynojet you have to remember. I dont want you to blow your car up, take it easy and a step at a time but you have more power there.. Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
No worries, I would rather lost HP than my new engine. But I always start on a safe tune. I know you want to run richer on the dynojet.
My bypass is already vented to the atmosphere. I guess I need to open the hood longer.
I swear, I am just going to shoot a 150 shot to get my 600 hp.
My bypass is already vented to the atmosphere. I guess I need to open the hood longer.
I swear, I am just going to shoot a 150 shot to get my 600 hp.
Last edited by Ed Blown Vert; Oct 18, 2005 at 12:55 PM.
Thread Starter
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From: Sunny San Diego
You know I just remembered something. On both dynos, a couple of times my AFR shot down to richer than 10:1 under the curve.
What else could cause the AFR to be really rich?? I wonder if that is what happened on the track. I am going to see if I have those EFI logs.
This is starting to make sense. That is probably why I could not lean out the AF under the curve with PE.
What else could cause the AFR to be really rich?? I wonder if that is what happened on the track. I am going to see if I have those EFI logs.
This is starting to make sense. That is probably why I could not lean out the AF under the curve with PE.
Make sure COT is shut off, that will give you random episodes of the super rich..
It will take some playing with, I'm sure you have a lot more left. I would probably max the blower out and see what happened before I bought a new head unit but ultimately its what you need to do if you want big power, the D1 will move more air with less impeller speed (that equals less heat also). You can even wind it up a little higher with the present combo and see what happens at the track.
I assure you if you increase the timing down low you will pick up at the track. Remember that with little to no boost you are no different then a head/cam motor, you can ramp the timing back as the boost comes up. With 8psi and good pistons you would have to detonate pretty hard to hurt anything long term.
It will take some playing with, I'm sure you have a lot more left. I would probably max the blower out and see what happened before I bought a new head unit but ultimately its what you need to do if you want big power, the D1 will move more air with less impeller speed (that equals less heat also). You can even wind it up a little higher with the present combo and see what happens at the track.
I assure you if you increase the timing down low you will pick up at the track. Remember that with little to no boost you are no different then a head/cam motor, you can ramp the timing back as the boost comes up. With 8psi and good pistons you would have to detonate pretty hard to hurt anything long term.
Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
Thanks, COT is turned off. I am guess OLFA is causing my issue.
But that is my plan, to do what I can with the P1 first and make sure there are not any other issues. I would hate to spend another $2k and still have the same issues.
Once Wendy gets back to me, I'll see if there is any issues running the ATI 7.65 crank pulley with their set-up.
Ya, I set everything flat @ 17* to be safe. But ramping down the timing is a good idea. It all makes sense.
Thanks for all the help.
But that is my plan, to do what I can with the P1 first and make sure there are not any other issues. I would hate to spend another $2k and still have the same issues.
Once Wendy gets back to me, I'll see if there is any issues running the ATI 7.65 crank pulley with their set-up.
Ya, I set everything flat @ 17* to be safe. But ramping down the timing is a good idea. It all makes sense.
Thanks for all the help.
so you pretty much think its your tune and your IATs causing the drop in power?so you checked your valvetrain and all is good?itd be great if it was just the tune and intercoolers.
i dunno if maybe im reading your log wrong ed but it looks like your injectors duty cycle#1 dropped to 50 in the same place that you picked up some knock,maybe im just pointing out the obvious dunno if itll help
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From: Sunny San Diego
Originally Posted by ddnspider
so you pretty much think its your tune and your IATs causing the drop in power?so you checked your valvetrain and all is good?itd be great if it was just the tune and intercoolers.
Have not had a chance to check the valve-train yet.
I have also given this info to HPE. Erik was also suprised how my HP it made. His N/A cars make that much.
Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
Originally Posted by ddnspider
i dunno if maybe im reading your log wrong ed but it looks like your injectors duty cycle#1 dropped to 50 in the same place that you picked up some knock,maybe im just pointing out the obvious dunno if itll help
I'm telling you Ed, you need to dial in the VE and MAF tables. You're still using the stock tables, right ?
That heavy-breathing 383 has a much higher VE than a stock LS1, and you have opened up the airflow a lot over a stock motor so the MAF table has gotta be way off too.
I'll help ya do it !!
You can always go back to your current tune as long as you save it...
Rob (Bad30th)
That heavy-breathing 383 has a much higher VE than a stock LS1, and you have opened up the airflow a lot over a stock motor so the MAF table has gotta be way off too.
I'll help ya do it !!
You can always go back to your current tune as long as you save it... Rob (Bad30th)