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finally got dyno'd and something is up

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Discussion starter · #21 ·
NastyStang113 said:
How do you know it's the tune? A mechanical issue could be very well the problem.
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yeah I know...hoping thats not the case...what could I look for to check if its mechanical??? I wish I would have dyno'd one of my other tunes (bamachips or bbr) to see if the problem stayed with the other tune...I didnt even think about it...damn :mad:
 
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#22 ·
I wasn't saying I know its the tune...I was pretty much saying I hope its the tune for him and not something mechanical
 
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#23 ·
VanWilder said:
yeah I know...hoping thats not the case...what could I look for to check if its mechanical??? I wish I would have dyno'd one of my other tunes (bamachips or bbr) to see if the problem stayed with the other tune...I didnt even think about it...damn :mad:
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What happened to those tunes? You can't just reload them?
 
Discussion starter · #24 ·
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Discussion starter · #26 ·
highwayman24 said:
Yeah, so just reload one of the ones that you recall not having that dip.
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I've never dyno'd the other tunes so I dont know if they have the dip or not...hopefully they dont because if thats the case I will know its the tune and not mechanical...once the snow clears up here I will run them on the street and see if I notice it
 
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#27 ·
Timing is roughly 27-30 at WOT. Knock sensors are limited so there's no way the dip in his graph could be related to minimal timing being pulled with knock sensors.

VCT, it's set up for limiters, and VCT rolls up to 17 at WOT nice and smooth. I think it's something mechanical with VCT, or a clutch slip issue. I am acquiring the DRF Dynojet Run File to look at gear ratio to see if I can see something slipping drivetrain wise.

Air/Fuel was spot on, and timing was spot on for our mail order tune. It was .8% lean... less than a percent off from target 12.85.
 
#28 ·
If it makes you feel any better, mine feels like about 4psi of boost kicks in at 3100 RPM. Something is off somewhere but I dont have the cash to hit a dyno.
 
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Discussion starter · #29 ·
Ho_Edge said:
If it makes you feel any better, mine feels like about 4psi of boost kicks in at 3100 RPM. Something is off somewhere but I dont have the cash to hit a dyno.
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thats weird...call brenspeed and explain the problem you are having and ask them what parameters they would want to look at in a datalog and datalog the car and send them the file and they should be able to tell you exactly what and why its doing that and hopefully fix it for ya and it wont cost anything
 
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#31 ·
But why would the clutch slip at 3700 and not at 5250 (peak tq)? Maybe it warmed up and got grippier? What about looking at rpm vs time to make sure its not a dyno artifact? How stable was the rpm input?
 
#32 ·
Look at the graph... peak torque WOULD HAVE been 3500-5000. Right around 4500 being the absolute peak. It starts slipping as it gets above 300RWTQ and then begins to grab again as it slopes back down towards 300RWTQ. The angle of the torque increase up until 3500 RPM shows the line you can follow... it would have made another 15-20RWTQ if the car wasn't slipping.

RPM vs. Time as well as Speed vs. Time is steady and smooth. The RPM signal is great, with smoothing off it looks almost identical to smoothing at 5. If I had to guess I would say they went off the individual coil signal unharnessed using the grounded RPM pickup, because it's very smooth.
 
#34 ·
That's what I'm thinking. I think the disc may be shot, or the pressure plate is getting weak. I find it hard to believe it would be the rear, but the pinion angle needs to be set anyway. The rear should have no problem holding 300RWTQ even on a whooped rear.
 
Discussion starter · #35 ·
tillman speed said:
That's what I'm thinking. I think the disc may be shot, or the pressure plate is getting weak. I find it hard to believe it would be the rear, but the pinion angle needs to be set anyway. The rear should have no problem holding 300RWTQ even on a whooped rear.
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Hey man I've been talking to a few people about clutch choice and a lot of people said to get the spec 3+ instead of the 2+ because the 2+ wont last...do you think the 3+ would be a better route for what I'm trying to accomplish??? I've also had a few people tell me they hate the 3+ lol so I'm getting a lot of mixed answers...wanting to get the best deal for grip, longevity, and definately cost as being a car salesman and have REALLY slow sales the past 3 months money is really tight
 
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#36 ·
Hmmmm... I like the whole stage 3 or 3+ deal. The pricing on the 2/2+ and 3/3+ should be VERY close. Within 40 dollars of each other all of them I believe.

I would just ask people how they feel about the 3+ chatter. The 3+ will obviously hold some more torque which is great. Just try and find the consensus about how the daily driveability is. I know you're not 100% concerned about it, obviously having a big cam, etc. But you don't want something that sounds like a haiti earthquake when you're taking off from a stop sign.

I'm sorry was that joke too soon? :tomato
 
#37 ·
Here is what I would check. In this order.
-tune
-check for exhaust leaks
-clean your intake filter unless it is a deep red.
-clean your maf
-clean your throttle body
-get rid of your slowmaster exhaust
-see if you can find someone to tune your cams right.

and do you feel that power loss when you are driving? (and I am not shitting on you, just trouble shooting.)
 
#39 ·
navyman8903 said:
Here is what I would check. In this order.
-tune
-check for exhaust leaks
-clean your intake filter unless it is a deep red.
-clean your maf
-clean your throttle body
-get rid of your slowmaster exhaust
-see if you can find someone to tune your cams right.

and do you feel that power loss when you are driving? (and I am not shitting on you, just trouble shooting.)
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Tillman already proved it was drivetrain slip with the rpm / mph. That should be totally flat.
 
#40 ·
navyman8903 said:
And what does the clutch have to do with a dyno pull? ever. You pull in 4th gear.
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4th gear is where I noticed my clutch slipping during hard acceleration, too. If you read Tillman's post it explains basically how the engine out-torques the clutch and then it grabs again. That's a perfectly reasonable explanation.
 
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