20psi on pump gas, if you dont know, dont answer...

[dbsupra90]

just wanted to mention-

jake's turbo is a 4067, which is different than the pt67.

but i think its close enough you could atleast get some ball park ideas.

also, whether or not 12psi is its highest effeciency range, i think its kinda worthless to run it that low.

 

[tissimo]

on a 1j a 67 @ 12 psi makes like 360 or so whp.. I went 110 mph on 12 psi

 

[IJ.]

just wanted to mention-

jake's turbo is a 4067, which is different than the pt67.

but i think its close enough you could atleast get some ball park ideas.

also, whether or not 12psi is its highest effeciency range, i think its kinda worthless to run it that low.

Agreed may as well run a smaller turbo and get MUCH better spool/drivability.

 

[starscream5000]

Remember, I only stated it as being a good place to start out at instead of going 20 psi right off the bat

 

[IJ.]

The bigger turbo's come into their own after 18psi, if I had more ignition I'd be running more than my current 20psi daily

 

[QWIKSTRIKE]

"race gas is still VERY cheap here- 110 for $5.25/gal, 116 for $10/gal....ironic that it doesn't go up nearly as fast as pump gas...."


Now that I think about it, I remeber the local track selling CAM2 110 for $6.00 per gallon. I guess the C16 is following the oil companie trends.

Getting back to the turbo efficiancy topic. There is a guy by the screen name of Blitzsupra on SF. He dyno tested his T61 and then later on changed his turbo to a SP67(same A/R's) and redynoed. With same mods he dynoed:

T61 at 18psi....470rwhp SP67 at 18psi.....470rwhp
T61 at 26.5psi..576rwhp Sp67 at 27psi.....650rwhp

I wish the search function worked on SF so you all don't think I'm pulling these #'s out of my @ss. But I found it very interesting that his smaller T61 made the same power as his SP67 at 18psi. But the SP67 really made a big power difference at 27psi. I know this is not very scientific or mathematical, but it is a real world test that gives us an idea of were a 67mm turbo makes power compared to a smaller 61mm turbo.

You should be amazed the the sp67 a larger turbo made the same boost response at the lower setting as the smaller turbo and creamed it at the higher settings in power. Forward thinking is that the larger turbo performs better, and more eficiently where as the SP67 really shined at higher boost levels

 

[QWIKSTRIKE]

on a 1j a 67 @ 12 psi makes like 360 or so whp.. I went 110 mph on 12 psi

Yes but at what RPM level

 

[QWIKSTRIKE]

Agreed may as well run a smaller turbo and get MUCH better spool/drivability.

I would not run less than 15 lbs of boost on this turbo, and would get at least a 15 lb spring. Don't forget the boost can only remain double the waste gate with a boost controller reliably.

 

[Doward]

LOL, awesome information here guys!

Jake, I'll be going 2.75" when I get around to doing the 'full race' setup - as I'll be spinning about 7500rpm at that point.

2.5" will be great for me, for now - until I am ready to upgrade to a 2.75" inlet/outlet on the intercooler, there is no point.

As for the T61 getting outflowed by the T67, that's obvious The T67 will flow more efficiently from about 2-2.6 PR vs the T61. Hence, more power (that's where that 10-12% makes a hell of a difference, eh?)

The 4067 uses the same 66.7/84mm compressor wheel that the PT67/T04r/T04z use, to my knowledge. Jake, would you mind measuring and verifying that?

As for all the discussion on the IC pipe size, let me just add this little bit - you WILL lose performance with an IC pipe that is too small, but a slightly big IC pipe is not going to hurt your WOT performance much, if at all. It's simply one of those things that although small, will add up to make you just slightly faster than the guy next to you

Jake, I would run 2.75" piping on your setup - but that depends on your intercooler - what are you running there? It's more important to keep the airflow diameters the same than to fret over pipe sizes.

If yours are 3" in/out, run 3" all the way through.

 

[Reign_Maker]

(think of the person as the size of the motor)

Wouldnt you think of the person as the size of the turbo, since thats whats doing the blowing?

John: Im running a 12X24X4" IC, 3" in/out... Part of the reason I was thinking of doing 2.75" in was the space and fitment issues... Should I just stick with 3" full? And your turbo comp measurements sound right, but even though the PT67 has a 67mm wheel, isnt it designed differently than the GT67 wheel? *not as efficient* Oh, and my turbo is DBB, shouldnt that make a difference too?

 

[Zazzn]

Well I know it all has to do with efficency but, here's the problem how many of us know the exact VE of the engine, know the exact eff of the turbo. Have a intercooler temp probe?

Not very many. So i'll give you my first hand experiance.

I run 20 PSI on 94 sunoco all the time, around 22-24 on a chilly night made me detonate on a t04b with a stock intercooler.. (stock cools just as well if not better then my old 3.5" spearco it just doesn't have the same flow so 24 manifold was probably like 28 at the turbo)

On my sp63 I ran 20 daily however, I could feel the car dogg in the hot day sunlight felt like i was missing 30-40 HP probably due to some slight detonation. (on spearco 3.5")

On my 1jz twin k26 i ran 20-21 full 4" ic, 2.75" piping and again felt stronger in the night but wasn't such a hit like the 7m because I ran it a little richer then my older engines (11.2-11.8) vs 12.0-12.8

 

[QWIKSTRIKE]

Wouldnt you think of the person as the size of the turbo, since thats whats doing the blowing?

John: Im running a 12X24X4" IC, 3" in/out... Part of the reason I was thinking of doing 2.75" in was the space and fitment issues... Should I just stick with 3" full? And your turbo comp measurements sound right, but even though the PT67 has a 67mm wheel, isnt it designed differently than the GT67 wheel? *not as efficient* Oh, and my turbo is DBB, shouldnt that make a difference too?

We have the same turbo...expect close to the same results. The gt4067r has a larger turbine wheel I believe over the 67 flavor, and flows more. If the 3" pipe is finished dyno, and test to see what you get. I wouldnt scrap it before I found out it isnt working. Theory vs real world at your disposal by just using and seeing how it runs.

 

[kwnate]

Sounds like a sweet turbo.

 

[QWIKSTRIKE]

Well I know it all has to do with efficency but, here's the problem how many of us know the exact VE of the engine, know the exact eff of the turbo. Have a intercooler temp probe?

Not very many. So i'll give you my first hand experiance.

I run 20 PSI on 94 sunoco all the time, around 22-24 on a chilly night made me detonate on a t04b with a stock intercooler.. (stock cools just as well if not better then my old 3.5" spearco it just doesn't have the same flow so 24 manifold was probably like 28 at the turbo)

On my sp63 I ran 20 daily however, I could feel the car dogg in the hot day sunlight felt like i was missing 30-40 HP probably due to some slight detonation. (on spearco 3.5")

On my 1jz twin k26 i ran 20-21 full 4" ic, 2.75" piping and again felt stronger in the night but wasn't such a hit like the 7m because I ran it a little richer then my older engines (11.2-11.8) vs 12.0-12.8

Cant have street tune and track tunes the same...street should be a bit richer like stated to 11-11.8 max to avoid detonation at high boost levels.

 

[Reign_Maker]

Good stuff Zazzn... I wish we had sunoco here...

Qwik, I have the IC to TB piping made... I just havent had the turbo to IC piping made yet... So, should I go with 2.75 on that pipe?

Sounds like a sweet turbo.

its hard to get mad at you... Now hurry up and let me know what you're making...

 

[QWIKSTRIKE]

Good stuff Zazzn... I wish we had sunoco here...

Qwik, I have the IC to TB piping made... I just havent had the turbo to IC piping made yet... So, should I go with 2.75 on that pipe?
its hard to get mad at you... Now hurry up and let me know what you're making...

My fabricator went with 2.5" on that one and since the outlet on the trubo is 2.75 it will not hurt you IMHO.lol

 

[IJ.]

I'm using 3" in and out and actually saw a drop in spool when I changed from 2.5" (from 2200/1psi to 1900/1psi with the 3")

 

[MK3Brent]

Hrmm
Makes sense.

And that's pretty significant.

Ian: Was it 300rpm earlier FULL BOOST as well? (edit: I assume pressure reading at the manifold?)

 

[Emik87t]

I have a T61 setup similar to your build and i was running 20psi on pump gas for about 2 months. Now i'm rebuilding my motor because i detonated my #6 piston. I talked to Larry at SP and he said 20psi and pump gas are a big nono. Not sure about yours being a bigger turbo but my experience is going to be expensive. I would definitely mix some cam 2 or some kind of race gas to up the octance and that boost shit doesn't do a damn thing. And this happened to me within the last month.

 

[IJ.]

Brent: Yep manifold pressure.

And yes 300 earlier across the range.

As a basis for comparison it used to break traction in 1st 2nd and 3rd around the 4000 rpm mark now it was doing it at 3500.

This is just get rolling then plant the foot on a dry road.