Best Turbo for 3100v6

[Schmieder]

I know this question has been asked a million times. I searched but couldn't find any solid opinions regarding the 3100v6.

I have been leaning towards a GT2860 or T3 TO4B, E?

The Compressor Map for the GT2860 lines up really well, if I did it right. This is what I came up with.

RPM EFFICIENCY
1.5k 68%
2.5k 69%
3.5k 75%
4.5k 79%
5.5k 75%
6.5k 70%

The two peak islands run rpm 3700~5200 (76%-79%-76%)
4500 being the absolute peak in efficiency. Not bad range for a daily driver urban street car.

I formulated very detailed instructions using the following formulas

CFM = RPM x CID x VE x 0.5
.................1728

n(lbs/min) = (boost psi + 14.7) x CFM x 29
........................(10.73 x ( X*F + 460))

Temp Out = Tin + Tin x [-1 + (Pout/Pin)^0.263]
........................Intercooler Efficiency


Tin = 90 deg F + 460
Pin = -0.5 psig + 14.7
Pout = boost psi + 14.7
Pin/Pout = Compression Ratio

Corrected Flow = lbs/min x (tin/545)^0.5
....................... (Pin/Psia)



Can you guys share your experiences with what turbos work well for a 3100/3400 v6?

I'm pretty sure about the GT2860 but just want to be sure,

Thanks

EDIT: What about a T3/T4 with .60 a/r compressor and .63 a/r turbine? Will that be a fast spool, mid range boosting turbo w/o hitting surge or choking the high end at 6k rpm?

I would do this myself with the math and compressor maps but the maps are hard to find. Especially when one is looking for a specific compressor map.

[robertisaar]

squirrelpf.com has a good calc and a LOT of compressor maps...

but i have found(thanks to some clarification and direction from joseph upson) that for a stock small port 3100, the T04E-50 trim is perfect. i lucked out and got a 46 trim, which is also pretty damn good. not sure about the turbine side, but that should cover the compressor for you.

EDIT: i modified my configuration a bit to allow the 50 trim and it shows that you can hit ~425HP and still be at 76% efficiency

http://www.squirrelpf.com/turbocalc/index.php?version=4&target_peak_power=475&pr_ref=14.696&engine_disp=3.1&engine_disp_factor=0&target_af=12&bfsc=0.428&max_ic_loss=1.5&rpm_redline=6000&rpm_peak_power=5200&rpm_max_boost=4000&rpm_min_boost=3000&vol_1=78&vol_2=80&vol_3=72&vol_4=65&vol_1=78&vol_2=80&vol_3=72&vol_4=65&intake_temp_1=90&intake_temp_2=120&intake_temp_3=135&intake_temp_4=140&turbo_n=1&map_sel0=57

[Schmieder]

squirrelpf.com has a good calc and a LOT of compressor maps...

but i have found(thanks to some clarification and direction from joseph upson) that for a stock small port 3100, the T04E-50 trim is perfect. i lucked out and got a 46 trim, which is also pretty damn good. not sure about the turbine side, but that should cover the compressor for you.

EDIT: i modified my configuration a bit to allow the 50 trim and it shows that you can hit ~425HP and still be at 76% efficiency

http://www.squirrelpf.com/turbocalc/...=1&map_sel0=57

I just looked at the T04E 50 Trim compressor map and damn, that is a beautiful match. Thanks man, that is exactly what I was looking for.

[Schmieder]

squirrelpf.com has a good calc and a LOT of compressor maps...

but i have found(thanks to some clarification and direction from joseph upson) that for a stock small port 3100, the T04E-50 trim is perfect. i lucked out and got a 46 trim, which is also pretty damn good. not sure about the turbine side, but that should cover the compressor for you.

EDIT: i modified my configuration a bit to allow the 50 trim and it shows that you can hit ~425HP and still be at 76% efficiency

If you don't mind, what can you say about this turbo? I can't find a specific name for it to match a compressor map.

The stats are...

T3/T4
.60 compressor
3" In / 2" Out

.63 Turbine
2.5" out

Reasons why I am looking at this turbo are many. Price, clock position, Internal WG 8 psi, barbed hook-up at compressor exit, V-Band exhaust clamp, supports 350 HP and is computer balanced. Not bad for a china-charger.

If this turbo is close enough to the T3 T04E 50 Trim, I would be happy. Otherwise I need to purchase an external wastegate for the T04E. Not the biggest issue but it would make life easier due to engine bay space and design approach. Internal WG's definitely cut down on the welding, grinding, exhaust raw material and construction time/effort.

It does not list trim numbers as far as I can tell.

[robertisaar]

that doesn't show nearly enough info to know what it is...

link?

and here is the current page where mine is. they don't list the specs on the webpage, but i measured them myself about 3 years ago... the ebay page is pretty close though.

webpage

http://www.speedyracer.com/servlet/the-103/Turbocharger-T70-%28V-dsh-band%29/Detail

ebay page. apparently comes with a wastegate now...

http://cgi.ebay.com/ebaymotors/Super-T70-T3-Turbo-70-AR-Wastegate-Skyline-V8-Camaro_W0QQcmdZViewItemQQhashZitem27aebb83b0QQitemZ170435249072QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

[Schmieder]

that doesn't show nearly enough info to know what it is...

link?

Yeah, I figured that. That was the only info that was listed. Bad business imho. Was CXRacing.com

I was hoping to pick a turbo with an internal wastegate, but that idea seems far fetched.

I now see I must use an external wastegate if I want the proper turbo.

You use a T70? I checked the maps and it would surge big time for my application.

But since I decided on an external wastegate, the T04E 50 trim or the GT35 50 trim. Probably the T04E most likely.

[robertisaar]

You use a T70? I checked the maps and it would surge big time for my application.

"T70"

it's actually a T04E-46(knockoff), they just mislabel them on purpose.

[Schmieder]

"T70"

it's actually a T04E-46(knockoff), they just mislabel them on purpose.

Why in the heck would they mislabel them on purpose?

If I bought a T3 T04E 50 trim from the same supplier, would I get what I pay for?


Off hand question.....what is the ID/OD size of the vacuum hose running to the FPR from the MAP? 3mm? 5mm? It's cold outside and a muddy walk to the garage. But I'll trudge if I must.

[robertisaar]

Why in the heck would they mislabel them on purpose?

If I bought a T3 T04E 50 trim from the same supplier, would I get what I pay for?

Off hand question.....what is the ID/OD size of the vacuum hose running to the FPR from the MAP? 3mm? 5mm? It's cold outside and a muddy walk to the garage. But I'll trudge if I must.

i don't know if they have labeled the sizes correctly for all of their turbos, but the measurements for the "T70" are now pretty close to correct. the names are all wrong, but the measurements MIGHT be right... no idea on the FPR reference line... why do you ask? for a check valve or something else?

[Schmieder]

i don't know if they have labeled the sizes correctly for all of their turbos, but the measurements for the "T70" are now pretty close to correct. the names are all wrong, but the measurements MIGHT be right... no idea on the FPR reference line... why do you ask? for a check valve or something else?

Check valve plus other things. I am getting a vacuum line kit, all one color to clean up the engine bay appearance.

Plus, the vacuum line running from the plenum to the 'T' that taps the MAP Sensor and runs to the FPR is going to need some re-engineering to fit the check valve. Nothing major, just need to make room for the check valve. And the vacuum line running to the trans needs to be altered to make room for the turbo. But they are metal at one point so I figured I would just replace the line with equivalent steel line and new vacuum hose at the ends.

I see there are vacuum hose kits with different sizes. But being the perfectionist that I am, I was trying to isolate each hose needed.

Hey, can I keep the stock PVC Valve lined to the plenum? Or do I need to reinforce the PCV Valve with another check valve? Just wondering if anyone has had flow failures from mild boost of 8psi through the PVC. I don't want to get a dump canister but will if I have to. What are they good for anyways, how do they work? the concept is there but the mechanics escape me.


Thanks bro

[robertisaar]

i would use a check valve for the PCV, but that's because i think that the valve itself wouldn't block the boost that would be trying to push it's way in.

have you thought about what you're going to do with the other half of the PCV system?

the "dump cannister" basically catches the oil/mositure/combustion byproducts that would otherwise get sucked into the intake by the PCV system.

[Schmieder]

have you thought about what you're going to do with the other half of the PCV system?

Well, I know the front side connected to the plenum for vacuum at idle and the rear side is the fresh air feed.

Being so, I was going to line the rear fresh air feed to the intake before the compressor. But also considered running it to the intake after the compressor and after the MAF like it is stock na.

But I do have to investigate further to make sure such a system will work.

Am I on the right path? Any suggestions?

EDIT: I was wondering...Can the PCV intake on the rear (whatever it is called) receive 8 psi boost w/o any negative consequence. It seems if 8 psi was applied it would meet the 8 psi push at the PCV valve acting as a pressure balancer. But isn't there a purge solenoid over there as well?

There are some aspects of the modern engine that I haven't learned yet.

I'm half NOOB, half PRO...lol

[robertisaar]

think of it this way: if you allow boost into the back, it's going to pressurize the crankcase, and NOTHING benefits from that. the backside is meant for fresh, filtered, unpressurized air, so connecting it before the compressor is actually a great idea. i've also seen small filters used directly at the fitting, but i have yet to see them in stores...

[Schmieder]

Hey, I just read that vacuum in the crankcase helps the piston rings seal.

Soooo, what if I ran a vacuum line just before the compressor. What I am thinking is at WOT, the vacuum from the intake just before the compressor will induce a strong vacuum in the crankcase, stronger then an idle vacuum? Either way, it should help the rings seal better.

But since it is not typically done, that I am aware of, there is probably a reason why.

As far as I can tell, I need to add a check valve to the PCV Valve because the PCV Valve leaks pressure (bad) and the other side needs a fresh air source that isn't under pressure but is metered air. That seems tricky if the MAF is placed after the compressor like I am going to do, due to the BOV bleeding air before the MAF to prevent metered air escaping causing an overly rich condition stalling the engine after a strong WOT run.

[Schmieder]

think of it this way: if you allow boost into the back, it's going to pressurize the crankcase, and NOTHING benefits from that. the backside is meant for fresh, filtered, unpressurized air, so connecting it before the compressor is actually a great idea. i've also seen small filters used directly at the fitting, but i have yet to see them in stores...

But doesn't that air need to be metered? Or it will become a vacuum leak at idle/cruise. Or can I correct that issue through tuning the fuel since the leak will be constant at specific rpm ranges???

Also, placing the vacuum line to the fresh air intake to the crankcase and tap air just before the compressor will induce a strong vacuum at WOT.

My prior post questioned this. Will this help or harm? Because I could find a way to block the fresh air during WOT and open at less-then-boost conditions. Kind of like a FPR but for vacuum air.

EDIT: The only reasonable answer I can think of is placing the MAF before the compressor so the crank case can receive fresh METERED air. But then I would have to vent the BOV back into the intake after the MAF and before the compressor.

Or as I thought earlier, tune the tables to accept the vacuum leak it would be if the MAF is after the compressor.

What did you do?