projekteg

try to find a comp. map for that turbo, and you'll see that it will take high boost from a turbo that size to reach you're desired hp, but that turbo becomes inefficient at higher boost levels on higher revving motors. if your stock motor is 150bhp, that is roughly 130whp, 5 psi from that turbo, may give you 30-40whp, so really you'd be more like around 160-170whp, but yeah, around 200bhp if you just want it to sound better

Gavin

Haha I'm not just making ---- up. I cant defend this either because I obviously don't know as much about this stuff as you guys, but I'm not pulling #s out of my ***.

I will continue to do my research.

projekteg

he's running a hybrid t3/t4 (he doesn't mention exact specs). it won't be hard to reach the hp level you want, all we're saying, is it's going to be hard with that small turbo. if you get a bigger turbo that will flow more cfm's, you'll be good to go. the .48/.42 is one of the smallest t3's produced, you'll be able to pull 200whp out of it, but not at 5psi, and not much more than 200whp, but it will work

Gavin

Hmm ok.

I still don't see the direct connection between the psi that my turbo will be able to hold and the power that my motor produces, and how a person could calculate one with the other without factoring in other things, like that fact that I have 3 intake valves & ITBs with internal velocity stacks in my manifold.

Ok like for example, if you had say a DSM running the 11 psi or whatever that they run stock. It is possible to increase HP without actually increasing boost through other mods, correct? So arrant there many other factors that result in the actual power figures?

I'm really not trying to argue, just understand.

projekteg

yes, you're totally right, but turbo's become inefficient at certain boost levels, rpm's etc. turbo's have to breathe and be able to keep pushing air with out over working itself. think of that turbo like a small wheel on a bike, you're gonna be pedaling your *** off with small wheels trying to keep up with a guy that has bigger wheels but is only pedaling half as fast. the harder the turbo tries to keep up, the hotter the air gets, the less efficient the turbo is. that turbo WILL NOT make power in the upper rpm's, and that turbo WILL NOT be effecient enough to get 250whp.

Gavin

IC this makes sense to me, the motor is breathing harder on each stroke to produce this power, multiplied by rpm...

So is the loss in efficiency only because the air is hotter? Would my 8.9:1 compression pistons change anything (9.0:1 with the TRD head gasket)? Thats relitavely high for my motor, people usually go with the 8.0:1 pistons with a thicker HG.

I also dont understand how if the turbo can hold 5psi to the top end, what the difference would be between having a t3 and a t3/t4. Just because the air is hotter?

HMT-Admin

Some day I'm gonna have a son named Gavin

Nice setup =)

Gavin

Ha, thanks man =)

projekteg

the difference is cfm's 5 psi from a small t3 is no where comparable to 5 psi from let's say a 60 trim t3/t04e.

Gavin

Aah my brain hurts

So 5psi after the TB will allways ammount to something different between the two turbochargers? So air temp is not the only other factor? What am I missing?

CFM is the volume of air that comes out of the turbo correct? What difference does this make on the intake side if it can hold psi?

I'm sure this will click eventually..