Casper's Twins first dyno.

[dmaxvaz]

this right on the money. Need the turbos in the juicy part of the map at any case. If they run there with out gates they wouldn't be able to take advantage of them if they were there any way. This is what there made for (venting just enough exhaust to keep the turbos rpm down to the sweet spot). Suppose the 42 was at 95k-105k (big drive pressures too) but the big one was at 40k rpm. You could vent some gasses off the 42 to get it to 65k-75k and feed the rest to the 55 and make it go to 45k-65k rpm. If you do it right (for a particular elevation), you can size the a/r on the exhaust to do this. However if elevation takes a decent change (or the d.a.) the waste gates control this (turbo shaft rpm, back pressure to get in the juice of the map) and you can run smaller exhaust housing a/rs for quicker spool up. I think pat and ppe are shooting for around 45k-50k rpm on the 55 would be my guess to keep it around 75psi boost? These are approximates and would have to be adjusted accordingly to keep things where you wanted them (testing and fine tuning). This is where speed sensors, and drive pressure gages would be invaluable.

There see! Clear as mud eh?

this is exactly what i was saying earlier in the post

 

[GMC_2002_Dmax]

I gated both my turbos just incase i run nitrouse i have a way to control boost on the big turbo. I have alot to learn with were to set the waste gates (so i am no expert ) due to finishing the trk at the end of the year and not alot of track time. But the big twins are fun and dangerous at the same time, ask tony at ridge runner and Big dipper.

Having tuned Nasty Girl and Jay's truck I know very well how fast a properly tuned/twinned truck is.

Although I have not driven either I have enough seat time in both trucks and other seat time in a few other mid to high 10 second, really low 11 second trucks to know how fast they are.

When tuned properly and gated properly the spool up is unreal and the acceleration as well.

It is like riding a roller coaster, the acceleration on the drop is just like these trucks, and since I am a serious coater junkie it makes it all too familiar.

 

[McRat]

At this point we are just going to trust the engineers from Garrett who spec'd out the chargers for the RPM and engine output we called for. They did say we are supposed to run intercooling between the chargers, but shouldn't need gates.

Neither charger was working hard, and were in the center of their maps. I'm 12% below the target output, so I need to make adjustments to dial it up.

Also, this setup will be used at 6000-8000 DA and the power must be sustained for extended amounts of time. The cam and heads are stock, which won't be the case for the Bonneville engine.

It's amazing at how far the Dmaxes have come in the last two years. This engine produces over 300% of the stock engine output on pure diesel with no drugs, and is completely streetable.

Yet I consider it too weak.

 

[McRat]

By the way, the work PPE did is top drawer, and they custom fab'b it in under two weeks. The dialing-in is my job.

Thanks out to Joe, Dan and the rest of crew at PPE for a job well done.:hug:

 

[super diesel]

By the way, the work PPE did is top drawer, and they custom fab'b it in under two weeks. The dialing-in is my job.

Thanks out to Joe, Dan and the rest of crew at PPE for a job well done.:hug:

There it is. No doubt about it. Garrett sepec'd the chargers to. I'm sure this set up will be nothing short of amazing. Looking forward to the out come.

 

[1badmax]

There it is. No doubt about it. Garrett sepec'd the chargers to. I'm sure this set up will be nothing short of amazing. Looking forward to the out come.

Garrett spec'd my set up but they had me put in 2 60mm waste gates, because i tolled them i might run nitrous.

 

[super diesel]

Makes sense. Tony told me you had put together a wicked ride. Way to go man. Been lookin at doing one of these for quite a while. To many other things going on (resetting up shop).