a step up from the pt61

[shine1stang]

ok given my recent dyno pull, im over working this pt61 w .81 exhaust housing. My hp peaks at 4400 and then drops off quite a bit. In running some numbers the turbo at 5k and 2.36 pr is struggling to supply the 58lbs/min of airflow.
Im not looking to make more power, just to be a lil more efficient, and not worry about overworking the turbo in the upper rpms. Even if i do go with a bigger turbo, ill turn the boost down to make same power. Im happy with being the only 3.8l v6 mustang to hit 600rwhp. I just dont like the drop off.
I was looking at mayb the 67mm, or possibly the master power 70.
U guys have the best knowledge of v6 turbo stuff. So lay it on me!!

 

[bison]

ok given my recent dyno pull, im over working this pt61 w .81 exhaust housing. My hp peaks at 4400 and then drops off quite a bit. In running some numbers the turbo at 5k and 2.36 pr is struggling to supply the 58lbs/min of airflow.
Im not looking to make more power, just to be a lil more efficient, and not worry about overworking the turbo in the upper rpms. Even if i do go with a bigger turbo, ill turn the boost down to make same power. Im happy with being the only 3.8l v6 mustang to hit 600rwhp. I just dont like the drop off.
I was looking at mayb the 67mm, or possibly the master power 70.
U guys have the best knowledge of v6 turbo stuff. So lay it on me!!

You should be peaking a lot later than that. Your torque must be well over 700 with a low hp peak like that. Id measure inlet air temps to see if you are really out of wheel. You shouldnt be at the rpm you stated For that power id go with a 6765

 

[shine1stang]

You should be peaking a lot later than that. Your torque must be well over 700 with a low hp peak like that. Id measure inlet air temps to see if you are really out of wheel. You shouldnt be at the rpm you stated For that power id go with a 6765

well here is the chart.... add 500 to the rpm to get actual. The tq is off because of non locking c4 converter. I figured tq to be around the 700 range as u stated. I do have a fairly small cam as well. 218/244 112 sep.
Intake temps b4 meth and 500 rwhp we 94* and ambient being around 50. After meth a cool 58.9* down the board. I do have a fmic as well.
That chart is basically just top end, as we got the bottom part dialed in, idk y he didnt just sample full run away. Oh well.

 

[bad V6]

Looks like tha car is making some good power. You do know that you are going to make Shiner jealous when you do make it to the track!!!

 

[shine1stang]

Looks like tha car is making some good power. You do know that you are going to make Shiner jealous when you do make it to the track!!!

thats my dad. he was there yesterday and was just as shocked as i was. I told him that i would be him to the 10s. Well he bought the black car w the 80mm and beat me there. His car is apart right now and im just gonna have to try to beat him to the 9s! i really cant wait till i hit the track to tell you the truth. I picked up 100hp at least from my last track visit, and ran a 10.71 then. Leaving off a foot/ebrake deal.

 

[bad V6]

Sounds like you need to beat him to the track. To bad that Beechbend has events scheduled for the next two weekends.

I met him last spring, in the staging lanes. I was surprised to see his car running as good as it was then. Although I believe he was running spray on the V6 Mustang. What are ya'll doing to his engine?

 

[shine1stang]

Sounds like you need to beat him to the track. To bad that Beechbend has events scheduled for the next two weekends.

I met him last spring, in the staging lanes. I was surprised to see his car running as good as it was then. Although I believe he was running spray on the V6 Mustang. What are ya'll doing to his engine?

was he in the black or silver car. The silver is sprayed and the black turbod, both v6. Well at nmra he cracked a head again, so hes starting with a new block and gonna build it all over again. no biggy.
well considering i work weekends ill prob have to wait till tue nite racing.

so im guessing that a 6765 is my best option??

 

[Quik Six]

My GN was nose diving after 4000 RPM's and a new set of valve springs cured that problem. Torque dropped 260#'s and RWHP dropped by 100 from 4000 to 5000 RPM's. Haven't re-dynoed it yet but difference in power is significant.:biggrin:

Just a thought.

Phil Engle

 

[shine1stang]

My GN was nose diving after 4000 RPM's and a new set of valve springs cured that problem. Torque dropped 260#'s and RWHP dropped by 100 from 4000 to 5000 RPM's. Haven't re-dynoed it yet but difference in power is significant.:biggrin:

Just a thought.

Phil Engle

well im running the comp cams 918 ls1 springs, and no one in the v6 mustang world has had problems w them. My first set was the faulty batch and i broke 5 in one run at the track. Im really thinking the nose off is from the small turbo, as it doesnt support this much power. Im running a c4 and with a 25% loss thats 750 at the crank.

 

[Quik Six]

My valve springs were about 7 years old and they were shot with less than 20,000 miles on them. Wish it had been the valve springs, that would have been an easy fix for you.

I can understand your concerns about the turbo's rated HP. I broke the barrier on my 6265 on a dyno test at 4000 RPM's and immediately put in a call to Patrick at PTE. He said their ratings were conservative and my turbo had more in it.

Best of luck to you. I'm still chasing gremlins myself.

 

[bison]

well here is the chart.... add 500 to the rpm to get actual. The tq is off because of non locking c4 converter. I figured tq to be around the 700 range as u stated. I do have a fairly small cam as well. 218/244 112 sep.
Intake temps b4 meth and 500 rwhp we 94* and ambient being around 50. After meth a cool 58.9* down the board. I do have a fmic as well.
That chart is basically just top end, as we got the bottom part dialed in, idk y he didnt just sample full run away. Oh well.

Why would i add 500 rpm? How did the rpm data arrive? Off an inductive pickup or was it calculated by the dyno? The hp and torque should be peaking much higher than the chart shows. I assume you meant 218/224 cam. I have a similar cam but @110 and i have it advanced 2*. My engines peak torque is at 5500. The exact rpm the converter flashed to under full boost. With the springs i had i was laying over at 6200 but the converter was efficient enough to get it across the traps. The car went 114mph in the eighth. My charge air temps were similar to yours. They were no more than 12* above ambient at anytime even up to 140+mph

 

[bison]

well im running the comp cams 918 ls1 springs, and no one in the v6 mustang world has had problems w them.

I had problems with them at high boost and 6200+rpm. Under 6k they seem fine as long as boost is 25 or less. 26120 is a better option imo.

 

[bison]

so im guessing that a 6765 is my best option??

Id go with a 68 trim ex if your looking to get the most potential power out of it. It will need more converter though

 

[shine1stang]

Why would i add 500 rpm? How did the rpm data arrive? Off an inductive pickup or was it calculated by the dyno? The hp and torque should be peaking much higher than the chart shows. I assume you meant 218/224 cam. I have a similar cam but @110 and i have it advanced 2*. My engines peak torque is at 5500. The exact rpm the converter flashed to under full boost. With the springs i had i was laying over at 6200 but the converter was efficient enough to get it across the traps. The car went 114mph in the eighth. My charge air temps were similar to yours. They were no more than 12* above ambient at anytime even up to 140+mph

calculated by the dyno im assuming, he said that since i didnt have a tach adapter that the rpms wouldnt read right We had this problem last time too. Yeah i meant 218/224. I dont rev above 6k, and my boost is 20 so i think the springs should be fine.
i really thank you for you help. I know being a ford guy people are less apt to reply. its whatever tho.
btw i have a bradco 3500 stall in my c4.

 

[bison]

calculated by the dyno im assuming, he said that since i didnt have a tach adapter that the rpms wouldnt read right We had this problem last time too. Yeah i meant 218/224. I dont rev above 6k, and my boost is 20 so i think the springs should be fine.
i really thank you for you help. I know being a ford guy people are less apt to reply. its whatever tho.
btw i have a bradco 3500 stall in my c4.

Based on your inlet air temps your cetainly not working the compressor side out of its range. Id be more interested in the backpressure reading. The 3500 Bradco should spool a ball bearing HPQ. Id keep cranking it till it runs out of steam. Its suprising to some how far you can go with less than everyone else has. Id disregard the dyno rpm numbers. If you have a 3500 stall its likely stalling to 5000+rpm at 20psi. Your numbers and combo look like an engine that makes really good power to at least 5800

 

[shine1stang]

Based on your inlet air temps your cetainly not working the compressor side out of its range. Id be more interested in the backpressure reading. The 3500 Bradco should spool a ball bearing HPQ. Id keep cranking it till it runs out of steam. Its suprising to some how far you can go with less than everyone else has. Id disregard the dyno rpm numbers. If you have a 3500 stall its likely stalling to 5000+rpm at 20psi. Your numbers and combo look like an engine that makes really good power to at least 5800

never thought of back pressure! hmm.
Screw it ill just run it and see what she does. I probably wont get to take it out for a lil while tho. Mayb the first tue nite racing at beech bend in april.
thanks for the help

 

[pontiac69fb]

It could be your small cam or heads that is holding you back from making power up top.

 

[bison]

It could be your small cam or heads that is holding you back from making power up top.

One thing i can say for sure the cam isnt too small.

 

[RUQWKNF]

Not too shabby for that setup.

Good power from that PT61 turbo and a very quick car ta boot.
http://www.gssmotorsports.com/New_Custom.html

Patrick

 

[bison]

Looks like he could gain even more out the back end with less gear when comparing eighth to quarter mph. Id try a taller tire first. Id bet it helps out.