New PT61 Problems - Running Slower Than A TA49

[AKTURBOTA]

Previously my TTA with the following mods has run a best of 11.79 @ 114.7 with a 60' of 1.61. Usually the car ran in the 11.90's.

8 position Caspers "Ultra Chip"
TA49 Turbo
36# injectors
Walbro 340 Fuel Pump
Action Fab 3” downpipe
freeflowing exhaust with testpipe
62mm throttle body
ported plenum
1" plenum spacer
adj fuel pressure regulator
ATR bleed valve to control boost
PTS 9/11 Torque Converter (Advertised 2800 but actually stalls at 3400)
LT1 MAF Sensor
Translator Plus
K&N 8" Air Filter on 3" Stainless Steel MAF pipe
110# valve springs
BFG Drag Radials on the stock rims
Spohn Adjustable Torque Arm
Global West Subframe Connectors
Spohn Adj Panhard Rod
Spohn Lower Control Arms
On the street I run 92 Chevron unleaded premium
At the strip I run Sunoco NOS Supreme Racing Fuel (117 octane)
Turbo Link used as my data logger

At the strip my fuel pressure is set at 45#'s with the vacuum off and I run 21-23 #'s of boost. I have run with the #5 chip which gives me 22 degrees of advance at WOT and knock retard usually never exceeds 2-3 degrees

I wanted to get my car solidly into the low to mid 11's as my performance goal for 2004, so I purchased a PT 61 P-Trim along with 60#/hr Moto Tron fuel injectors and upgraded my 8 position Ultrachip for the larger injectors. I understood that I needed a 3200 stall torque converter, but my 9/11 TQ was already stalling at 3400, so I thought I was OK.

I ran the car today and it was unimpressive. My best time was 12.40 at 113 with 2.0 60' times. This was with 41#'s of Fuel Pressure, 21-22#'s of boost and 24 degrees of timing at WOT. At first the car was running very rich with 44#'s of FP (O2's in the high 800's), so I leaned it to 41#'s (02's high 700's to low 800's)out accordingly and it helped. With the TA49 and the PTS 9/11 TQ I was stalling at 3400 with 14PSI of boost. With the PT61 I was stalling at 2800-2900 with the same TQ and getting only 4-5PSI.

I see that I probably have a mismatched torque converter for the "big" turbo, but I was expecting to turn at least 120mph in the qtr mile and only turned 113mph. What is wrong? I have logged all my runs on Turbo Link if anyone would like to see the details.

Confused and depressed in Eagle River, Ak

 

[Taffy]

3400 should be plenty for the 61. It looks like your AFR is a little lean. Maybe add some fuel?? You should be closer to the low 700s on race gas.

Of course, if you had a wide band kit, you could see what your actual AFR was.

 

[Slow91z]

Tune Tune Tune...It's there you just need some time to sort out the new combo...Also that 61 isn't even working at that boost range...Crank the boost up and get it into the sweet spot...Your 49 was "closer" to it's sweet spot at that boost then the 61 is, it likes higher boost.

My PTE-53 made made 20 more HP at 24 PSI then it did at 23 PSI.

 

[d0n_3d]

Mark...how ya doin buddy? glad to see you got the starting problem fixed! hey don't sweat the new times with the 61...you just totally changed combos and NOBODY gets it on the money the first few times at the track...like mentioned it's gonna take tuning...

I will tell you one thing though...that 61 LOVES high boost...21 lbs is not even getting started on that turbo...you need to crank it to 25 psi at least and run good 116 race gas...your stall should be fine...just lean it out some on the bottom end...but make sure you watch knock accordingly...last thing we all need is a blown head gasket...turn the boost up gradually and see what happens...that 61 should be pulling like a freight train

btw...that 2.0 60 foot tells me either you aren't launching with enough boost from the starting line (at least 10 psi!) or you are fat rich on the bottom end to start out with...no more than 1.7 60 foots!!!

 

[AKTURBOTA]

Don,

For whatever reason the TTA was flooded and that was why it wouldn't start. I floor the accelerator, turned the ignition on, it began to sputter, cleared it's throat and began to run. I don't know what exactly caused it to flood, but it hasn's happened since.

Yeah I understand it is going to take some tweaking to get the tune right with the PT61, unforetunately, I can only get out to the track once a month, so I think I am going to invest in one of those "plug into the cigarette lighter" accelerometers to provided me with the feed back I need on 60' times, 1/8 and 1/4 mile ET's and MPH's.

The PT61 feels real doggy at launch (4PSI and 2.0 60' times) , so I guess I will drop the Fuel Pressure from 41#'s and use my Translator Plus to richen the fuel so that I don't go lean at the back end of the quartermile. I understand that I need to work on getting the the PT61 to spool like it should on the bottom end to get me back to turning 1.6 short times, but since the PT61 flows more air shouldn't my MPH have improved over the TA49 at the end of the quartermile?

 

[1991syclone]

Please check with one of the trans guys to verify this but, the lower boost is producing lower HP or TQ. If you get the boost up the convertor will go to the 3,400 RPM or higher. IE trans brake. If you go with a looser-higher stall, when you get to the boost you had before, it may be too loose or much higher than 3,400 and cause you a different set of problem/s. Stall speed is changed by TQ or HP, which is why most convertors get one free stall change. When I put my T-66 the 3,200 would only go 2,800, I raised it 500 RPM and for the street it got the turbo in range. Foot stall went from about 2,000 to a little over 2,500 which gets the boost up instantly, but then it jumps to 4,500 to 5,000 as soon as the boost hits. I had to raise the shift point to 6,000. The same is true of brake stall it is now at 3,200 but comes up real fast when the boost climbs.

 

[onequick6]

Originally posted by AKTURBOTA
Previously my TTA with the following mods has run a best of 11.79 @ 114.7 with a 60' of 1.61.


I ran the car today and it was unimpressive. My best time was 12.40 at 113 with 2.0 60' times.

Your 60ft dropped 4 tenths which definataly doesn't help. Most likely caused by your converter. I would look into getting the actual stall on the converter checked out.

 

[GNVYUS 1]

IF you were to get the identical 1.61 60ft, you would of pulled an 11.6 which was your goal.

Most likely your BLM is WAY off down low, check it out and see.

Your car is a dog down low and thats not the converters fault. 3400 is plenty for the Pt61, which spools similar to a TE44.

 

[AKTURBOTA]

The BLM's with the PT61 at WOT were 112 from launch through the top of 3rd gear, this is at 41#'s of fuel pressure. in comparison, the BLM's for the TA49 were 131 at WOT from launch through the top of 3rd gear and this was with 45#'s of fuel pressure.

I compared the PT61 run for which the converter stalled at 2800 and 5 psi to my best run with the TA49 for which the torque converter stalled at approximately 3200 and 17.5 psi.

Caspers is going to recalibrate the Ultra Chip they sent me to in order lean it out a bit since it is running so "fat" throughout the quartermile run.

 

[TurboDave]

You have virtually no tuning time on this setup, and you're surprised it went slower??????

I also see you are running a Translator plus. Why in the world do you need to still tune the fuel pressure jig??? All of your adjustments to fuel should be made in the Translator, if not, it's a total waste!

You might also think about upgrading to an LS1 MAF with that big new turbo.

Remember, that turbo is capable of moving a LOT more air than your old one.

Set your fuel pressure for proper idle BLM's and USE THE TRANSLATOR TO TUNE!!! That's what it was made for.

Tune, tune, tune.

 

[GNVYUS 1]

Yep, 112 is really fat and exactly why your 60ft went south on you.

Those injectors are still pretty new on the market and its not surprising that it needs to be leaned out. I am sure John will dial it in for you. But Turbodave made a great point, from here on out dial it on with the Translator.

I bet when you get back to running around 128 you will be pulling 11.4's in no time.

 

[AKTURBOTA]

Thanks for all your comments. I have installed the Extender Chip and will set my BLM's for 128 at idle. My question is should I keep the fuel pressure at the recommended 45#'s and use the T+ to get the BLM's to 128 at idle, or should I use Fuel Pressure to get to 128 and then use the T+ to tune WOT thereafter?

 

[87gn-newbee]

Mark set the FP around 42 and leave it then use the T plus for base/WOT.

I think I finally might have my car straight when are you going back to the track? Keep me posted

Dan

 

[AKTURBOTA]

Hi Dan,

I am going to try to get to the track hopefully, once in August and again for Labor Day. Again, this all depends on the family situation. I am swamped at work and I have my cousin coming from Finland to stay for a week in the first part of August.

I will let you know when I can go to the track. Let me know when you can go too, so hopefully we can coordinate and go together.

Once I get the car leaned out, I hope to crack the 120 mph barrier...I think it should be able to do that with the PT61 turbo when it is tuned correctly.

Mark

 

[DonnieShort]

I just recently got this turbo. And from what I've learned this turbo likes to be wound out. I mean, high boost launch and big boost for top end. Keep playing with it and you'll find it's sweet spot.

 

[southern boost]

Hey mark

I have this turbo back on my car now it loves the boost around 25 psi and taffy was correct to say the 02s in the mid to low 700s . My car launched at around 7psi when I ran the numbers in my sig. and it went 118 last nite in crappy air .


well any way ,if you got any Qs just give me a shout .I love this turbo and you will when you get it tuned .



randy

 

[Ed Valvo]

What's your 02's down low like on the launch or in 1st gear? Leaning it out through the chip on the low end, since FP will affect your whole RPM range, should help spool up the turbo and get you out of the hole better. I went through all that with my turbo. I got beat by a TE-44 on street boost levels. When we went to the track and cranked it up, I thought he let off because I blew past him so strong. I was wrong, he never lifted.... BTW, stock style 02 sensors are not the most accurate type of 02 however I have picked up 1/2 second and quite a few mph leaning out it from high 700's to mid 700's.

 

[d0n_3d]

Guys...I got my car running and it's been going for about 2 weeks now...all I got to say is this turbo is pulling harder at 18 psi of boost than my TE-44 ever did at 25 psi!!! I've already got into a race with a new GTO on a top end run (80-120mph) and walked it very easily...this turbo is crazy! I can't even imagine 25 psi. Keep tuning and run good gas. Any car with this turbo should be flat out FLYING.

 

[DonnieShort]

Originally posted by d0n_3d
Guys...I got my car running and it's been going for about 2 weeks now...all I got to say is this turbo is pulling harder at 18 psi of boost than my TE-44 ever did at 25 psi!!! I've already got into a race with a new GTO on a top end run (80-120mph) and walked it very easily...this turbo is crazy! I can't even imagine 25 psi. Keep tuning and run good gas. Any car with this turbo should be flat out FLYING.

Don I agree. The PT 61 Ptrim pulls harder at 18 psi than my 52 did at 25-26 psi. It's freakin' nuts!! And boy does it like the top end . I've only got to run it in the 1/8th and ran 7.24 @ 93.74 mph and it was still pulling and pinning me in the seat through the traps ( 1/8th remember ).

But I found one very interesting thing, my crossover pipe at the driver side header was cracked over ½ way around so I wonder what I was giving up because of that?? Got it fixed this weekend and it spools as good as the 52 did. Boost comes up faster and so much stronger. When it gets to 5 psi it's already breaking my BGF dr's loose ( 275-60-15's ) and gets up to 25 psi at the snap of your finger.

 

[JDSfastGN]

dammit you guys stop posting good things about the 61, everytime i read a post of how much better it pulls with a 61 compared to a 44 or 52 i just keep wondering how much mine would pick up with a 61 Yall are making it hard not to make the purchase when or if i come into enough money