New Rotrex C38R Supercharger

tiller · 03-08-2018, 06:11 PM

Quote:

Originally Posted by Jinxx

88mm supercharger pulley

This is a chart on impeller speed calculation...last time I talked to rotrex they confirmed the calculation as well .....and that is why GTM wouldn’t sell a pulley under 86mm

Ya I have all that, don’t you have the 85mm installed on yours?

Jinxx · 03-08-2018, 07:28 PM

Quote:

Originally Posted by tiller

Ya I have all that, don’t you have the 85mm installed on yours?

Yes the 85 mm

Elmo370z · 03-08-2018, 06:12 PM

Quote:

Originally Posted by Jinxx

88mm supercharger pulley

This is a chart on impeller speed calculation...last time I talked to rotrex they confirmed the calculation as well .....and that is why GTM wouldn’t sell a pulley under 86mm

When is the car going to up and running

Jinxx · 03-08-2018, 07:26 PM

Quote:

Originally Posted by Elmo370z

When is the car going to up and running

Mine is running with the 85mm pulley ...12 lbs boost

TopgunZ · 03-09-2018, 07:36 AM

Quote:

Originally Posted by Jinxx

Mine is running with the 85mm pulley ...12 lbs boost

What are your whp/wtq numbers on 12psi? What fuel are you tuned on?

Jinxx · 03-09-2018, 01:55 PM

Quote:

Originally Posted by TopgunZ

What are your whp/wtq numbers on 12psi? What fuel are you tuned on?

I’m tuned with 93 octane

pokeyl · 06-06-2018, 07:35 AM

Quote:

Originally Posted by Jinxx

88mm supercharger pulley

This is a chart on impeller speed calculation...last time I talked to rotrex they confirmed the calculation as well .....and that is why GTM wouldn’t sell a pulley under 86mm

The 84mm is at 91280 at 7k rpm......a 80 mm would put you over 100k ...
Also TOPGUN is correct ..if you blow the supercharger you could damage much more than just the bottom end .. we all take that risk when boosting but ....I wouldn’t go that far over specs on a blower

I might be reading the charts wrong soooo ......im still not sure

It's my chart and you are reading it correct.

Jinxx · 03-08-2018, 09:49 PM

The 85 mm pulley is running 96k impeller speed at 7.5 k rpm and 90k at 7k rpm

Using a 80mm would be running 102k impeller speed at 7.5k rpm and 95k at 7k rpm

That might be stressing the rotrex pretty hard

tiller · 03-09-2018, 04:30 AM

Quote:

Originally Posted by Jinxx

The 85 mm pulley is running 96k impeller speed at 7.5 k rpm and 90k at 7k rpm

Using a 80mm would be running 102k impeller speed at 7.5k rpm and 95k at 7k rpm

That might be stressing the rotrex pretty hard

Yes, I ran mine all last summer with 85mm at 7.5k with no issues as of yet, I’ll retune n try the 80mm at a 7k redline, like I said I usually don’t redline the car often I’d like to see what type of power differences there is lower in the rpm range where I like it, also may even try some different rear gear ratios as well

Jinxx · 03-09-2018, 07:31 AM

Quote:

Originally Posted by tiller

Yes, I ran mine all last summer with 85mm at 7.5k with no issues as of yet, I’ll retune n try the 80mm at a 7k redline, like I said I usually don’t redline the car often I’d like to see what type of power differences there is lower in the rpm range where I like it, also may even try some different rear gear ratios as well

I think it will be a wash in difference....what you gain from smaller pulley will be lost from lower rpm
And I have different gearing as well .. the nismos came with I think. 3.96 gear...non nismo was a little lower ... 3.69 if I remember right

tiller · 03-09-2018, 08:22 AM

Quote:

Originally Posted by Jinxx

I think it will be a wash in difference....what you gain from smaller pulley will be lost from lower rpm
And I have different gearing as well .. the nismos came with I think. 3.96 gear...non nismo was a little lower ... 3.69 if I remember right

guess we will see, it sure was a big difference between the 90mm and the 85mm after installed, it brought the boost in earlier but I think a little bit earlier would be even better, but that's just me and where I like my power and boost to come in, I think roughly a 7100k redline wont bother me to much, I reviewed my logs from last summer and they show a redline of 7587k redline with the 85mm while tuning with seb, if I don like it then its only 6 bolts to put the 85mm back on.

Jinxx · 03-09-2018, 04:28 PM

Quote:

Originally Posted by tiller

guess we will see, it sure was a big difference between the 90mm and the 85mm after installed, it brought the boost in earlier but I think a little bit earlier would be even better, but that's just me and where I like my power and boost to come in, I think roughly a 7100k redline wont bother me to much, I reviewed my logs from last summer and they show a redline of 7587k redline with the 85mm while tuning with seb, if I don like it then its only 6 bolts to put the 85mm back on.

I agree with the boost sooner ..that’s why I went with the 85mm ....the 80mm would be another notable difference early in the boost range which is what’s we are wanting ....that’s why the c38r should be a big improvement for our platform

TopgunZ · 03-09-2018, 06:49 PM

C38 vs R
KgPS .065/.08= 15%
12.5psi x 1.15 = 14.375psi

jmroy6 · 03-09-2018, 07:03 PM

Are you saying the c38 lineup is kapped at 12/13lbs on this platform? Cause its not. The c38-91/92 flows 82lbs/min thats more than a pte 6266. We prolly only see 12/13 lbs due to the restriction of a 3" intake.

Quote:

Originally Posted by TopgunZ

C38 vs R
KgPS .065/.08= 15%
12.5psi x 1.15 = 14.375psi

Jinxx · 03-10-2018, 12:13 PM

Quote:

Originally Posted by TopgunZ

C38 vs R
KgPS .065/.08= 15%
12.5psi x 1.15 = 14.375psi

They haven’t released any specs for the c38r yet....how did you get that comparison ?

03-09-2018, 06:49 PM	#13 (permalink)
TopgunZ A True Z Fanatic Join Date: Jun 2012 Location: Minneapolis Posts: 2,651 Drives: 06 350Z , 09 370Z MT Rep Power: 6834	C38 vs R KgPS .065/.08= 15% 12.5psi x 1.15 = 14.375psi __________________ ROTREX SUPERCHARGER TUNER KITS - $6799/ CUSTOM STILLEN AIR TO AIR KITS -$2100/ 700+ WHP!! WWW.TOPGUNSPEEDWORKS.COM

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