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Thinking about getting a T67



I've never looked into turboing a 3800 so someone school me, where is the powerband on a pt61 and where is it on a t67?

From what I've learned about turbos, I think it would take a few extra supporting mods to get the potential of a 67.
 
Explicit_Spade said:
I've never looked into turboing a 3800 so someone school me, where is the powerband on a pt61 and where is it on a t67?

From what I've learned about turbos, I think it would take a few extra supporting mods to get the potential of a 67.
Click to expand...

power band depends on cam and head choice, smaller turbos with a smaller ar spool faster than bigger turbos with a larger ar, you can have a smaller turbo with a huge ar and it will spool slow as ****, there is alot more in making a good running turbo set up than just slapping any old turbo on a car, thats why alot of people go with turbo kits the turbos are sized properly for what your going for, my t67 spools up in the 3500rpm range but alot of spool depends on your exhaust set up like headers and down pipe size and how restrictive your cat back is or if your even running a cat back
 
darkhorizon said:
a T67 is a 600whp+ turbo.. completely pointless for any car not planning on making 600 on "low boost" and 700+ on high boost.

Most fwd guys cant use more than 425whp anyway, get something small, cheap, reliable, runs well on a stock converter/trans instead of the mess that is a T67... Unless you want to go for "huge" power on slicks.
Click to expand...

This.

Explicit_Spade said:
I've never looked into turboing a 3800 so someone school me, where is the powerband on a pt61 and where is it on a t67?

From what I've learned about turbos, I think it would take a few extra supporting mods to get the potential of a 67.
Click to expand...

A pt61 will come in around 2500-3000 and make power throughout the entire rpm range. A T67 won't make power until 3500-4000.

People get caught up in dyno numbers and not actual "usable power". Making power from low rpm to high rpm is best unless you're building a dedicated drag car. Do you really want to limp around town with basically n/a Grand Prix until you can get that turbo spooled in your upper rpm range?
 


Do you really want to limp around town with basically n/a Grand Prix until you can get that turbo spooled in your upper rpm range?
Click to expand...

Spool speed is pretty dumb to talk about.. brake boosting/antilag will put a 61 and a 67mm turbo on the same playing field in terms of spool speed. The 67 is a bit laggy in first gear, and most cars will not see full boost until late in 1st gear without a big PSI launch. My old T3 turbo fiero setup would make full boost in ANY situation as long as I could lay a tiny amount of brakes on it... antilag works quite well for cruising around.

Driving my T67 GTP around I never brake boosted or antilaged it.. and i never ran more than 14psi because it was stuipid. I never drove that car to race it really, because it just was a completely usless vehicle for that sorta stuff.

With turbo, powerbands dont exist.. If you have the pedal down, you make as much power as your wastegate wants you to make... Every dyno sheet from my turbo cars showed peak power when the boost spikes a psi over target at 4200rpms.. otherwise its dead flat... This was tested with modified timing camshafts, big cams, small cams, big turbos, small turbos.. its all the same.
 
for real i could show you a dyno graph of my car it starts a over 500whp and ends at over 500whp, when it starts to spool it jumps to 5 or above grand almost instant
 
And your a/r is what?

If you really believe there is no such thing as a powerband on a turbo you need to do some serious reading.
 


.68 ar/ they make power untill your motor cant rev any more and how much boost determines how much power they make, from the start of a pull to the end i gained about 50whp, my dyno was done in mph rather than rpm but with in 5mph it went from nothing to just under 500whp and stayet right around there for the rest of the gear, you put the go pedal down and the second the turbo lights up its over 5k rpm
 
Are you saying you had 450whp at 5mph? Then got up to 500whp by the end of the pull?

We're you dynoing in first gear? Was this a dynojet or mustang dyno?
 
third gear, im in the process of uploading the dyno graph and it was a mustang dyno, it started around 89mph and by 93mph it was 475whp then climbed to 522 at the end of third gear
 
Interesting... I'm not into bench racing so I will never claim to be a syno expert but that graph looks pretty flat.

This is a graph of a member local to me, notice how power jumps when he hits the throttle and continues to climb.
ImageUploadedByTapatalk 21369756035.405121.jpg

You might benefit from a bigger area/radius or larger compressor.
 


it looks to me like his climbs for 20mph and drops off the rest of the run but still shows the same thing he is damn close to max power almost instantly, im going to benifit from turning the knob a few more turns lol that run was only 17lbs of boost, i built a new motor this year and a better fuel system that can handle more boost, that turbo will be fine to make 650-700whp on my new set up
 
My max power is achieved between 3100-3500 RPM with my PT-61. I really need to get a better shot that includes the mph etc. This is copied from build thread.
e1cda581.jpg
 
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