slay2k

Hi alberto, thanks.

Actually there are quite a few people with built motors and the PE kit. And while nobody is pushing beyond 600whp yet, I think the turbos are capable of at least that =) Guess we'll have to wait and see.

thawk408

iTrader: (16)

I was wondering this exact same thing, becuase on www.350tt.com they state that the PE kit is limited to 450rwhp. This number did seem kind of low to me, just wasn't exactly sure.

SQUILL

based on the flow charts i did i would say 16 psi max boost 7000 rpm shift points and i would guess 550-570 whp range max. This would be on a built motor of course.

These turbos look very happy to run 12-15 psi so you are only limited to the strength of your stock motor at that point!

Sharif@Forged

iTrader: (92)

Gurgen's map shows the PE's efficient all the way up to 21psi...at 7000rpm. Squill, do you know the reason for the discrep?

GurgenPB

iTrader: (2)

Well. I think squill looks at the shift points, and on his map the 6.5K rpm line reaches the PE1420's max flow rate of 14 cubic meteres/min at a slightly lower boost (~18psi) point than on mine (21.5 psi). See below:

His map can be found here:
https://my350z.com/forum/showthread....threadid=81141

Also, he may also be referring to the fact that the inner most envelope goes go up to 15 psi, but we can go all the way up to 21 psi by losing relatively little (1-4% efficiency). The first point is more of a concern i believe (to me as well).

Squill, did you use any further factors aside from the normal formula of [213.4xrpm/3456]xPR/2 to find flow?

Gurgen

SQUILL

Hmmmm the formula looks good but your chart starts @ 0 psi while the actual raw chart you sent me actually starts off at 3 psi(1.2 bar on the un edited raw chart) not 0. When you made the new graph did you compensate for this descrepency?

by my calculations at 7000k rpm engine demand per turbo is 433 cfm.

I went back to my chart and the 7k line was off by a bit however based on my calculations just above 18psi shifting at or below 7000rpm you will be running the turbos on the verge of choke limit or into choke depending on real world function.

Running a turbo anywhere near choke limit would not bee a good idea. I would still say 16 psi max for these turbos.

What are ur thoughts gurgen?

GurgenPB

iTrader: (2)

Shoot I uploaded the wrong one ... Here is the right one



Squill,

So I assume you got the excel file... From your update, your chart is now identical to mine.... that's somewhat of a relief, as yours predicted a worse case scenario...

HEre are my thoughts ..... given that I have an AT and have less control over my shifts... i have to look at where the AT shifts for me. In all but 1st gear, the AT shifts at 6600 indicated, which is about 6200 actual (at least on my car... this has been verified many ways ...techtom unit readout, the fact that i hit the rev limiter at 7500 indicated while it's set at 7100, etc). In 1st gear, the AT will shift at 7000 indicted (6600 actual), but in M mode will shift at 6600 actual just as in all other gears.

So, if we consider 6500 actual to be the highest that I will likely hit (and of course I can have TS program in, say, a 6700 rpm redline to be safe instead of the current 7100), based on the new correct chart, I will approach the choke limit at just over 21 psi (and at true 7000rpm at ~18 psi).

So, IMHO, i think there is more than 16psi that these turbos can run at.... especially seeing as they are pretty efficient at those levels b/w 4000 and 6200 rpm.

What are your thoughts?

GurgenPB

iTrader: (2)

Oh, the email i sent you, Squill, got bounced back to me (your hotmail box is full). I guess you never did get my excel file... Even without that, I am glad we are coming up with the same numbers now..

One more note... you mentioned real world conditons... Wouldn't the actual flow of air that reaches the engine be at a lower PSI than that generated by the compressors, considering the pressure drop from the piping, intercooler, etc? If so, does this mean that we need to be more conservative in how we approach our setup than what's predicted by the flow map?

G

Lorca@Z1

Just for fun, here's my PE1420 dyno at 24.4 psi

SQUILL

^ what engine is this chart off of? what car?

GurgenPB

iTrader: (2)

was about to ask the same thing...

SQUILL

Yes our charts look pretty much identical now. In real world conditions would be the true test of how much psi these turbos are good for and this is where my lack of practical experience would prevent me from making an accurate determination.

remember boost guages are measuring manifold boost pressure which is after the pressure drop of the IC and plumbing.

A good turbo system should lose roughly 1 psi or less through its plumbing.

I do believe you need a margin of error though running these turbos into choke would be detremental to its top end performance although 6500rpm to 7000 rpm at wot comes lightning quick so it wouldnt be at choke wery long unless it is hitting earlier in psi than we are showing on the graphs.

If you are able to talk to PE at all i would be curious to know what they believe is the max boost of their turbos on the VQ35DE

another thing to consider is that perhaps a high boost setting may perform better shifting at 6200 rpm than at 7000 rpms.

It all depends on how this motor pulls on the top end if the car pulls better eta's shifting @ 6000-6200 than @ 6800-7000rpms then this would allow you to run higher boost levels as well.

It all depends on how this system acts in the real world i suppose.

GurgenPB

iTrader: (2)

Exactly what i was thinking about the pressure drop. The PR shown here is the pressure just after the turbos.... So if the drop is about 1-2 psi through the plumbing/IC, then you would need to subtract that much from the boost level shown... which makes me think more and more about not going too low of a compression with my pistons

Gurgen

SQUILL

9 to 1 is the number! When i finally get my install going (APS) i will be going 9 to 1 forged internals.

Lorca@Z1

VG30DETT

SQUILL

Ahhhh this makes sense then yes the cfm demand is alot lower due to having 3.0L to feed vs 3.5L..Nice numbers by the way

erknjerk

550-570 whp for a built motor is a bit to high. The compression will most likely be dropped to maybe the 9.5:1 or 8.5:1 range. The high compression of the stock motor is the main reason it makes so much power for the boost of these kits. Also PSI is relative the the piping diameter, the thinner pipes show more PSI at the same flow rate. On a built motor assuming the heads and cams are polished and matched it might equal 550+ due to the flow efficiancy increasing(hopefuly good quality workmanship). But if built just for rod strength you might be disapointed in HP#'s.

Lorca@Z1

Thanks, its a blast to drive