Twins, Drive pressure, boost and gauges

[Chad]

With a set of twins (or triples for that matter), what is the optimum drive pressure and boost information to monitor via gauges?

Primary charger drive pressure and total boost?

Drive pressure and boost for both?

Just drive pressure for primary and boost for each turbo?

Anyone use Hewitt Industries dual boost gauges? And if used in this scenario would you monitor both turbos on one gauge and drive pressure on the other looking for relations in drive pressures or the obvious relations in boost? Or the standard way of drive pressure and boost for each together on separate gauges?

I know actual turbo configuration, type, size, blah, blah, blah, of course make a difference but I'm speaking in generalities and would like to hear various theories or experiences, hopefully with details.

Thanks,
Chad

 

[MAXX IT OUT]

I was looking at this one....
http://www.ebay.com/itm/52mm-Black-...Air-Pressure-Gauge-GS-C713-DUAL-/350548912829

 

[Chad]

I was looking at this one....
http://www.ebay.com/itm/52mm-Black-...Air-Pressure-Gauge-GS-C713-DUAL-/350548912829

Haven't those before.....could be a nice feature to see numeric info as a clear reference....

 

[Roc8man]

With a set of twins (or triples for that matter), what is the optimum drive pressure and boost information to monitor via gauges?

Primary charger drive pressure and total boost?

Drive pressure and boost for both?

Just drive pressure for primary and boost for each turbo?

Anyone use Hewitt Industries dual boost gauges? And if used in this scenario would you monitor both turbos on one gauge and drive pressure on the other looking for relations in drive pressures or the obvious relations in boost? Or the standard way of drive pressure and boost for each together on separate gauges?

I know actual turbo configuration, type, size, blah, blah, blah, of course make a difference but I'm speaking in generalities and would like to hear various theories or experiences, hopefully with details.

Thanks,
Chad

I have the Hewitt dual needle gauge and use it for total boost and drive pressure to help tune my twins (4094 billet 68mm / s480sx4). I like the gauge and sitting next to it in the overhead mount is an EGT gauge. Seeing them side by side while I'm hammering the throttle is easier and with the dual needle you can easily tell if your tuning is close or needs adjustment

David

 

[Chad]

I have the Hewitt dual needle gauge and use it for total boost and drive pressure to help tune my twins (4094 billet 68mm / s480sx4). I like the gauge and sitting next to it in the overhead mount is an EGT gauge. Seeing them side by side while I'm hammering the throttle is easier and with the dual needle you can easily tell if your tuning is close or needs adjustment

David

What size base is your s480? T6? Or does the sx4 specify it as T4? Did you ever run that over a stock unit? Or has it always been with the 4094? What kind of boost is that set up pushing?

And your basically running the plumbing to read drive at the 4094 and total boost, correct? Where'd you tap for your drive pressure line?

 

[mb1]

I tapped the exhaust manifold for DP, if you do this see if you can pick a location that is NOT directly in the path of exiting exhaust gas, I have to run a needle gauge just barely cracked open to dampen the pulsing through the line so it doesnt rattle the gauge too much. ( I picked a spot that was easy to drill and thus, directly in the path.... hindsight.... ) Also I normally have the valve closed and gauge removed, only used it for tuning purposes.

Watching the intermediate and total boost pressures work together is interesting and cool though. I have boost x2 and egt in a triple pod on the pillar.

 

[Roc8man]

What size base is your s480? T6? Or does the sx4 specify it as T4? Did you ever run that over a stock unit? Or has it always been with the 4094? What kind of boost is that set up pushing?

And your basically running the plumbing to read drive at the 4094 and total boost, correct? Where'd you tap for your drive pressure line?

It's a Borg Warner S480SX4-2 (http://www.turbodriven.com/files/pdf/S400SX4-2.pdf). It's T6. I had the MPI small kit (stock vgt/4202) combo since 2008 and decided to go with larger twins when I had my engine built early this year so the S480 has never been over my stock unit. Pushing 50 psig boost right now and it's total boost being read.