F2 is definately not undersized for the application, mainly used to light the turbo. The truck had egr delete a long while ago, studded, but under boost kept blowing the gaskets. A new set of heads, a while on a surfacer, bigger sticks, tranny rebuild, and the thing will fry 38's in 4wd. The main issue with the truck is fuel now I believe, it needs more, even with the liftpump, bigger sticks, it blows soot for a few seconds then is clean.

 

Are there any questions you guys feel should be asked, whether I go dmax or cummins?

 

Any idea why they can't get the cumming done faster? Is it just due to the custom install or parts need to be made?

 

Fabrication, wiring harness, lots of stuff adds up.

 

u trading up the tacoma to an H1??

 

Still have both tacomas for now....and an h1 lol.

 

Shit navistar head castings, or it needs fire rings - what kind of air does it have aside from the PC? That's frustrating.

Does it have a modified HPOP?

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I would drive them and see what you like. You need to have a very clear - and honest - idea of what you are going to want to accomplish with the engine. You say you only want 500whp now, is that going to change? If you're anything like me you're going to want more.

If you're going to go for more than that at any point in time... You're going to want to wait for the Cummins or spend the money to have the bottom end of the dmax built before it goes in ($$$$).

Not worth the heartache and cost of not doing it right the first time.

 

500 max. This will be a daily driver.

This might come off stupid, but can you adjust boost on the fly with a diesel? Was thinking of running low levels of boost for DD and turning it up for the occasional fun.

 

Well, as a bit of "buyer beware" - there are guys who DD more than that, and if you delve into the diesel world deeper you'll find people telling you that so beware.

Not stupid at all. You're going to want to turn the fuel down, aka load a more mild computer tune. I am not sure if this can done on the fly on common rail diesels. There are boost controllers but they are not employed to accomplish what you're after. A proper tune takes care of everything - with any computer tune purchase you'll get 3-4 files standard + extras for a fee.

More boost ≠ more power. There's only air and fuel (no spark plug in play) so fuel dictates boost - meaning boost level is a direct result of the amount of fuel being called for which is dictated by the tune. More fuel = more exhaust = turbine wheel spins m0ar = m0ar b00st = vtec kikz in, bichez

You are also going to want as much air as possible (volume first, boost second) at any given time to ensure the most efficient burn of the fuel possible. This gives you no smoke and more power.

Think of it this way, and this is going beyond your question but I think it's still relevant. The turbo is a heat pump. It has a range of efficiency. More boost can actually mean less power if you push the turbo off its map, which is also why it's important to ensure you have a sufficient turbo for the power level you want.

Most importantly, boost is a measure of restriction, not of air volume nor of power.

You can run into massive drive pressure issues with turbos that are undersized, even on stock trucks with a tune. Generally on stock diesels with a hot tune you're pushing the turbo off the map and looking at 1.75-2psi of drive pressure (pressure between the exhaust valve/manifold and exhaust wheel of turbo) vs the ideal 1:1 ratio.

In ways, drive pressure is the turbo equivalent of parasitic loss w/ a supercharger.

 

All I can say is predator motor sports was awesome! I'll write everything up and post pics later.