How streetable is a PT-70 with my current combo?

I had a 54 on my old setup and it was a decent turbo.

I'm now running a 70 on the street with a .85 PTE hosuing, stock heads and a now-to-tight converter (was 3500 @ 3psi before being fixed, now 2800 @ 0psi). Boost is a little lazy till about 5psi then it shoots up pretty quick. I have a .63 Garret housing to put on it (Thanks Walt :D ) and it should be great on the street. Spoolup with the old converter was REAL quick.

I'm glad I run Nitto DR's as my street tires. On regular radials the car will just spin the tires when the boost comes up. The DR hold good on the street (although the do break loose the top of 1st on colder days)

I havent had a chance to really lay it out on the track, but at 15psi it went mid 12's @115 with no traction.

I am in the process of getting together my GN1 heads. The car should really fly then.


Cliff Notes: 70 on the street = yes You can't beat the sound of a large turbo sucking in the air :D
 
I don't get some of you people. You are going 12's with a mid 10 sec turbo, and you want to get a bigger turbo. The key is tuning. I still have a stock turbo, and am almost going mid 11's with only 20psi.
 
Originally posted by forcefed3.8's
I don't get some of you people. You are going 12's with a mid 10 sec turbo, and you want to get a bigger turbo. The key is tuning. I still have a stock turbo, and am almost going mid 11's with only 20psi.
:eek: almost mid 11's on a stock turbo! That is outstanding! I have seen people go 11.7-11.8 on the stock turbo but usually higher than 20 PSI. What is your secrets?
 
I'm sorry but there is NO way a stock turbo will push a full weight GN to mid 11's. It simply wont move enough air, especially @20 psi.:rolleyes: They are usually maxed out in the low 12's. If you are going that fast, you must be doing it on the motor instead of relying on boost.
 
I have a pt70,55s,3500 stall it leaves hard but almost to hard for the street.you have to really be easy off the line even with my 28x10.5 m/t slicks
 
I run an Art Carr off the shelf 19930 Converter with a CPT70-BB Qtrim Turbo, .96AR, and it spools like you wouldn't believe yet still has GREAT driving manners. Turbo alone doesn't make anything "unstreetable", its the overall combination.
 
Originally posted by forcefed3.8's
I don't get some of you people. You are going 12's with a mid 10 sec turbo, and you want to get a bigger turbo. The key is tuning. I still have a stock turbo, and am almost going mid 11's with only 20psi.

Thats good for a stock turbo. What MPH are you running?

Show me a list of people who have gone mid 10's with a PT-54 or similar mid 10sec turbo.

I went from a TA-54 with a .85 exh housing to a LT-70 with a .85 exh housing and the car pulls MUCH harder on the top end (bottem end is a little laggier with the big exhaust housing which is going to be fixed soon)

The car ran 117mph at 21psi with the 54 and 115mph at 15psi with the 70.... big difference there (both with 27deg chips and a mix of C-16 and 91 octane pump gas)

I've been around these cars long enough to learn alot not be scared of big parts.

55# & 72# injectors, 3500 Stall 9" N/L coverters and Big turbos TE-45A-PT70+ are FINE on the street as long as you got the right parts to back it up. Is my car fast right now? Not really, at least until I put the GN1's on and get the tuning and traction worked out, but with limited money you have to buy parts as I can afford them.

I drive my car daily. In-fact its the only car I own right now except for the rolling chassis I have for sale. The car can get decent (20mpg) gas milage, it will idle and not get hot all day, its perfectly docile till you get your foot into it. Thats the joy of a turbocharged car.
 
Well, the trick is removing all bottlenecks. I have a 2.25" pipe in place of the inlet neck of the intercooler, ported heads, bellmouthed stock TB, ported turbo, 3.5" intake plumbing, hooker headers and a 2800 stall. I am trapping 115 right now. I plan on lightening up the car some this winter and maybe a .82 exhaust housing and a V4 intercooler.. This was just a general comment on people with large turbos barely in the 12's wanting to go bigger.
 
Originally posted by forcefed3.8's
I don't get some of you people. You are going 12's with a mid 10 sec turbo, and you want to get a bigger turbo. The key is tuning. I still have a stock turbo, and am almost going mid 11's with only 20psi.

How heavy is your car with you in it? What was your mph?
 
I don't know the weight, it is a fully optioned GN with power seat and even elec climate control. I have steel bumper backers and cast iron drums. My 85 has aluminum drums and bumper backers and weighed just shy of 3800 with me in it. I weigh 175. I was going 115mph. With ported heads and a stock turbo, I am maxed out at about 20 psi. I run a race chip with something like 31° timing. I am hoping to push it more this coming summer, but I will likely change to a TE60 along with an intercooler. I bolted on a PTE51 and with 20psi on pump gas and a low timing chip, I went 118mph.
 
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