Track times on new setup. Help me find my bottleneck!

Oh, I'm familiar with the chip and setup. Ran that for a while. Like I said, optimal setup for the track was different than for the street since the conditions are different. Easier for the track since you just need to tune around the alky on the launch as the rest of the run is stable.

But as far as your car not liking lots of alky... its just a tuning issue. If you could run 100% alky it would love it. You've already proved its a tuning issue in that the car picked up after you turned down the alky. Its not because the car runs better or makes more power with less alky, its just because it couldn't be tuned around it.
 
Yeah that’s what’s bothering me most. Id imagine a 6k shift at a later mph may drop the rpm down closer to 5200 rather than 5000 and help accelerate the car quicker in 2nd and 3rd and begin to couple quicker up top having started at a better rpm/power in each gear but I still feel like 5700 in 3rd is excessive for the current combo and mph. I will talk to Dusty and see what he says. They have adjusted it a few times and even added a sprag to help it couple but maybe its time to try and adjust the combo to match the converter a bit better rather than expecting the converter to do something it can’t do at this lower rpm/power.
the car is backhalfing 24/25.7mph and is taking 1.9 sec/1.77 sec on the 10.6 pass to cover the last 320ft of the track at 3700lbs its not too bad.the 1/8 to 1000ft takes 2.1/2.09 sec,thats 340ft,the 330 to 1/8 needs 2.48/2.41 sec to cover 330ft.60ft to 330 is 270ft and this varies from 2.98 to 2.85 sec solely due to the power you left on.so after the 60ft, the first 270ft and the last 320ft are the only et swings,670ft in between is just about the same.look at your shift points in these areas.inmo the car is really down on torque and slow to climb up on engine rpm it should be much higher in mph at the 1/8 and et should be much quicker from 100ft to 1000ft.if this car was hitting 110mph in the 1/8 with a 26mph backhalf you would be at 136mph.heavy car,tight converter,lame rear gear, big turbine wheel,are the contributing factors and the transbrake is masking the fact that the combo is way to soft on the low end of the rpm range.
 
It takes ALOT of power to make a 16 blade PTC work. That converter usually goes 4.80's 1/8th in a 3200# car.
 
the car is backhalfing 24/25.7mph and is taking 1.9 sec/1.77 sec on the 10.6 pass to cover the last 320ft of the track at 3700lbs its not too bad.the 1/8 to 1000ft takes 2.1/2.09 sec,thats 340ft,the 330 to 1/8 needs 2.48/2.41 sec to cover 330ft.60ft to 330 is 270ft and this varies from 2.98 to 2.85 sec solely due to the power you left on.so after the 60ft, the first 270ft and the last 320ft are the only et swings,670ft in between is just about the same.look at your shift points in these areas.inmo the car is really down on torque and slow to climb up on engine rpm it should be much higher in mph at the 1/8 and et should be much quicker from 100ft to 1000ft.if this car was hitting 110mph in the 1/8 with a 26mph backhalf you would be at 136mph.heavy car,tight converter,lame rear gear, big turbine wheel,are the contributing factors and the transbrake is masking the fact that the combo is way to soft on the low end of the rpm range.

Thank you for the insight. I hope I don't come across as argumentative. I'm not sure how we keep referring to the converter as so "tight" when it doesn't couple up top. The early track ET loss is most likely due to the 5200 rpm 1-2 shift lugging it down a bit and my tendancy to not put my foot 100% to the floor after the launch. Comparing to other similar time slips a friend sent me, his car went a few hundredths quicker from 60-330 and he ended up (4.312 vs my 4.348 even thought my 60 ft was 1.498 vs his 1.514.) He ended up 10.559 vs my 10.61 even though my car out trapped him in the 1/4 by almost 1 mph. So really, picking up a few hundredth down low isn't going to gain the 6-8 mph in the 1/8th it would need to trap 135. The car is missing power and 15% efficiency at 5700 rpms has to have something to do with it? Maybe Ive made my mind up that the converter is the issue (tight down low, but loose up top?) I mean thats a mechanical calculation that tells me the engine is turning a certain rpm but losing 15% through the converter and not translating to driveshaft rotations. I realize its popular (and more ideal for my combo) now to run a 6466 or 6266 but the billet dbb 6768 was an awesome deal I couldnt pass up. It feels far from lazy or lacking torque down low. Spool is instant and maybe its the 25.6" tall MTs on the street giving some more gear but it feels fantastic from a 20 roll on the street if it hooks. Thanks!
 
It takes ALOT of power to make a 16 blade PTC work. That converter usually goes 4.80's 1/8th in a 3200# car.

I didn't choose a 16 blade, it was spec'd by Dusty after my 17 blade unit proved it didnt want to couple on my 6776/234 combo. so im not sure what other tricks were done inside other than adding a sprag. Other than fin angle and blade count converters are voodoo to me :) I'm open to getting it adjusted again or going a different route but Im not sure which direction to head.
 
Do you have anything logging voltage ?
Only ECM/ignition voltage that power logger logs. I need to clean the contacts of the ignition switch as they are only mid 12s under full load. I just fixed a large voltage drop between the battery and alternator by adding another main ground to the battery from the alternator housing the week before I went to the track.
 
Almost sounds like something shorting out under boost. Like a wire shorting out on a downpipe, header etc........
 
Almost sounds like something shorting out under boost. Like a wire shorting out on a downpipe, header etc........

I drove the car once to work since the track day and fuel pressure held during every pull and i didn't see the issue again. I had just installed a fresh wideband sensor the week before the track but its weird that the car felt perfectly fine when it went lean and on the 10.67 run where it showed 14.7 at WOT for the last couple seconds my narrowband actually went up from 780s to 790s during those frames which is making me think there is something wrong with the WB sensor after a prolonged pull possibly. Narrowbands aren't accurate but they should at least follow the trend of the wideband.
 
The reason we say tight converter is that usually people have to tighten up the converter as they add more power. With the same converter, as you throw more power to it, it will start coupling at higher and higher rpms (the rpm it drops down to after the shift). As someone said above, 16 blades are usually on the highest hp cars. If you run a 16 blade at low power it will couple at a real low rpm usually out of the powerband of what most combos want. A 16 blade converter is tighter than an 18 blade. We are just talking the coupling and stall, not up top. In my experience with an 18 blade it couples very good up top at high power or low power. But I know of someone with a 17 and now you with a 16 that aren't coupling the best up top under medium power.

I went through your 10.61 log on PowerLogger..... Your converter does not seem to be coupling as tight as I would guess. Still tight at close to 5000 rpm but not too far off from what I would guess. The gears and taller tires at that weight are probably hurting you down low and costing you in the 1/8th. I would guess that is why Dusty spec'd the 16, since your gears and weight may present issues trying to couple up top. Other things from the log.... you were in and out of the throttle for 6 sec before you launched. Way too long. Maybe 3 sec or so should be more than enough. And you need to move your seat closer... over 2.5sec before you were over 4v on TPS. Not sure what the chip is set to WOT value at but you want to be WOT.

As far as the blip up top.. showed on the 10.61 log too. My guess is fuel pump. You can see the Injector DC% going up at the end of the run as the A/F shows lean. Could be wideband crapping out but that is typical spot fuel pump will show.... I guess if you blow up you'll know for sure. The injector duty seems high at 70% for that power on alky. Need someone to run the numbers... could be making up for poor fuel pump out put at high boost. You are probably at 72-75psi fuel pressure... do you have a fuel pump spec vs pressure?
 
The reason we say tight converter is that usually people have to tighten up the converter as they add more power. With the same converter, as you throw more power to it, it will start coupling at higher and higher rpms (the rpm it drops down to after the shift). As someone said above, 16 blades are usually on the highest hp cars. If you run a 16 blade at low power it will couple at a real low rpm usually out of the powerband of what most combos want. A 16 blade converter is tighter than an 18 blade. We are just talking the coupling and stall, not up top. In my experience with an 18 blade it couples very good up top at high power or low power. But I know of someone with a 17 and now you with a 16 that aren't coupling the best up top under medium power.

I went through your 10.61 log on PowerLogger..... Your converter does not seem to be coupling as tight as I would guess. Still tight at close to 5000 rpm but not too far off from what I would guess. The gears and taller tires at that weight are probably hurting you down low and costing you in the 1/8th. I would guess that is why Dusty spec'd the 16, since your gears and weight may present issues trying to couple up top. Other things from the log.... you were in and out of the throttle for 6 sec before you launched. Way too long. Maybe 3 sec or so should be more than enough. And you need to move your seat closer... over 2.5sec before you were over 4v on TPS. Not sure what the chip is set to WOT value at but you want to be WOT.

As far as the blip up top.. showed on the 10.61 log too. My guess is fuel pump. You can see the Injector DC% going up at the end of the run as the A/F shows lean. Could be wideband crapping out but that is typical spot fuel pump will show.... I guess if you blow up you'll know for sure. The injector duty seems high at 70% for that power on alky. Need someone to run the numbers... could be making up for poor fuel pump out put at high boost. You are probably at 72-75psi fuel pressure... do you have a fuel pump spec vs pressure?

I agree that the gears are probably throwing a wrench into the efficiency along with the lower rpms. I was in and out of the throttle on the brake because the car next to me staged and then didn't light the 2nd bulb for what seemed like an eternity. Without an rpm limiter or 2 step the car builds boost very quickly and can go higher than id like. Its sensitive but more track time will help that.

The car was in PE mode for sure throughout the run but keeping my foot down is a mental thing i need to correct. I agree injector duty cycle seems a bit high but not too far off until the WB starts creeping leaner and the chip reacts. Yes fuel pressure is 72ish at WOT.

The lean issue didn't replicate on the street but comparing the wideband leanout trend to the narrowband on all passes is leading me to think there is an issue with the wideband after a full pull which is hard to replicate on the street. Narrowband increased in high gear which tells me its reacting to the chip commanding more fuel since a narrowband usually shows leaner throughout a run due to the extended exhaust temps. Fuel pressure was rock steady throughout my passes on the street this past week.
 
The specs on your fuel pump look ok... looks like it matched to the injectors at 12v... 480 lb/hr or so. It would have to be at 70% or less capacity to be an issue. Which happens.

Running some quick numbers and comparing to some of mine... looks like you are running a decent bit more inj DC% then you should for that power. Two things come to mind... you are either running more fuel than you need (too rich) or the injectors are working harder than they should t make up for some restriction (filter or pump). Put it this way... you are running more inj than I did on my low 9 145mph pass on dual nozzles. I am lighter but still over 100 more hp on that run. Doesn't add up.
 
The specs on your fuel pump look ok... looks like it matched to the injectors at 12v... 480 lb/hr or so. It would have to be at 70% or less capacity to be an issue. Which happens.

Running some quick numbers and comparing to some of mine... looks like you are running a decent bit more inj DC% then you should for that power. Two things come to mind... you are either running more fuel than you need (too rich) or the injectors are working harder than they should t make up for some restriction (filter or pump). Put it this way... you are running more inj than I did on my low 9 145mph pass on dual nozzles. I am lighter but still over 100 more hp on that run. Doesn't add up.

Awesome thank you for that info. Pump voltage was 13.8-14.1 when alternator was 14.4 or so when I checked . I need to possibly get another bung welded in and put an buddies lc1 wideband to compare to mine. Maybe the zeitronix is not as accurate as it should be and my “10.6” target is really 10.0 or something. Would explain quite a bit.
 
The specs on your fuel pump look ok... looks like it matched to the injectors at 12v... 480 lb/hr or so. It would have to be at 70% or less capacity to be an issue. Which happens.

Running some quick numbers and comparing to some of mine... looks like you are running a decent bit more inj DC% then you should for that power. Two things come to mind... you are either running more fuel than you need (too rich) or the injectors are working harder than they should t make up for some restriction (filter or pump). Put it this way... you are running more inj than I did on my low 9 145mph pass on dual nozzles. I am lighter but still over 100 more hp on that run. Doesn't add up.

Awesome thank you for that info. Pump voltage was 13.8-14.1 when alternator was 14.4 or so when I checked . I need to possibly get another bung welded in and put an buddies lc1 wideband to compare to mine. Maybe the zeitronix is not as accurate as it should be and my “10.6” target is really 10.0 or something. Would explain quite a bit.

Didn’t have time to read everything but you don’t have enough data to know what’s really going on. 3.23 is way too much with the power level you’re at and especially if using a bias ply slick. I wouldn’t expect gains with 3.23 until the engine is spending a lot of time over 5800. The 16 blade is likely aggravating it. You likely aren’t getting enough manifold pressure in 1st and 2nd where it’s really needed to move the heavy car with too tall gearing. A properly plumbed external wastegate with some smart control and some changes to the converter, gears and weight of the car could net several mph and more than half a second on the next outing. The suspension will need to be totally different to handle the power it should be making. 93/alky isn’t a good fuel choice when trying to run a turbo that’s going to have a lot of drive pressure is used. It just makes the compressor work a lot harder to move air and increases charge air temp and drive pressure which both reduce mass flow. We always saw big gains with larger diffusers using compressor wheels that are capable of moving 90lbs/min or more of air. Speed density would also likely be very beneficial here


Sent from my iPhone using Tapatalk
 
So really, picking up a few hundredth down low isn't going to gain the 6-8 mph in the 1/8th it would need to trap 135.
torque is what moves the car.think of it as whats doing the work through the 1/8 not just one area.
 
I hope I don't come across as argumentative.
not at all.may be a bit stubborn but i can handle it;)all kidding aside that rear gear is a recipe on much lighter cars or cars that make alot more power.heavier cars need more fuel especially when the gear is pulled out and on a turbo buick motor the rpm s climb to slowly inmo which is why it has a very linear pull or endless pull with a combo like yours.large turbine wheels,larger ex housings,heavy car and a slower rpm climb rate hurts the cars when your trying to et them,if your car was 800lbs lighter you would have a big smile looking at your ticket.
 
Top