Mike D

As Adam mentioned, I've been running Mach 6's with my current turbo. I haven't drag raced with it for obvious reasons. I received my turbine housing back from getting coated. I hope to have this new charger on by this weekend's end.

I think the 6's will push this turbo really nice, but we'll see.

Aosipower

Just a thought, but why would you want something with such a massive exhaust wheel (Sliver 62 ->74mm) to run on the top of a twins setup. Wouldnt you want a smaller exhaust wheel, like a 65mm to optimize spoolup?? I can see how it would be awesome if you are planning to build a huge full race style set of twins but for a daily driver isnt the point of twins near-instantaneous spoolup while still being able to support good power. I just don't see a silver 62 spooling well as the top turbo in a twin set without a whole LOT of fuel (i.e. more than mach 5's).

Dont get me wrong, I think mach 5's with a sliver 62 would be a great setup as a single, I just think it would be less than optimal if you are serious about upgrading to twins in the future. Especially if you want it to be a fast spooling daily driver.
Just my thinking...
-Alex

IngrahamS

if and when i do goto twins I would run bigger injectors probably 6's or 7's with a monster pump, but for now i need the truck for a realiable daily driver that needs to go 100 miles a day with no problems. i just wanted to see if the 5's would be too hot for the 62, if I could do a 64 and 6's i might think about it but like i said before i don't want to be afraid of WOT runs.i would love a quick spooling 575-600 hp truck which i do know is very hard or impossiable with a 62 or maybe even a 64. May just have to go with the 66. for what i want and hope the cam and head spool it fast. thanks for all of the info guys.
-Stew

Mike D

The reason I stayed with the 64 over the 66 is two fold. First reason was the price, the 66 was way too much for what it is IMO. The other reason was, after speaking with Nathan Wright, he said the 66 will flow a sight bit more air than a 64. I forget the numbers, but it wasn't worth the extra x amount of $$ to me.

dzlfarmboy

I think the exhaust side on these chargers is more imortant that the larger compressor wheel, you can make good power with a 62 with a good exhaust side. But everbody looks more to the size of the compressor wheel but if you cant get the exhaust out quick enough under WOT its hurting your performance as well

IngrahamS

with the upcoming mods I have posted, will a 66 spool well with 6's? i don't tow all that often at all so all the truck has to do is haul me around. i know that would be good for 600+.
-Stew

dzlfarmboy

Yeah 6's will spool a 66 as good as anything, but you might like the quicker spooling 62/ 64 charger, my power was very close with 20hp of running a 62/16 66/14 and a 64/13 charger and I think it ran the best on the street with the 62. Just my experience.

Bret

Coon Smile

with my 200hp EDM's and the prostreet 66, i have no problem daily driving and temps. are in check (900* climbing hill, 600* cruise) with the new adrenaline on PL02 (1006), i get minimal smoke (maybe a haze) and it spools the turbo extrememly well under normal acceleration...

Coon Smile

i agree...my s300 62/14 was a blast to drive on the street but i upgraded to the 66 for the fact that i could peg my 1500* pyro in a HURRY!!!

dzlfarmboy

Yeah but even on my 66 I could still peg the pyro, just didn't see much drop in temps, and a 62 is just alot funer on the street.

HOHN

Correct that the 74mm will be laggier on top.

But the reason you'd want one on the top charger is simple: efficiency. The larger the top turbine (more flow), the less flow must be diverted around it via the wastegate.

If hot gases are passing through TWO turbines instead of just ONE, then more work is being extracted from them.


Personally, I'd choose a larger housing over a larger turbine wheel on top, though. For example, an HTT 16ss housing on a 71mm wheel will flow more than their 14cm housing on the same wheel. In other words, the housing limits flow more than the turbine does, and therefore the housing is the place to be going bigger on top, not necessarily the turbine wheel.

Given shared designs, a larger turbine is always more efficient than a smaller one. Unless, of course, I'm wrong

JMO

Coon Smile

i obviously dont have as much fuel as you

Aosipower

Right, I know the effeciency would be increased. You hit on my main point which is spool up, it would just be laggier is my point. I too would run a larger housing vs a larger turbine wheel.

The advantage of a larger housing vs more massive wheel would be that a larger housing would increase efficiency without the added rotational mass of a larger turbine. Yes? Therefore you keep your efficiency without continually having to add more energy just to get/keep the heavier wheel moving...

JMHO...

Back on topic...I think you would like the 62 better for the street also...if 600+ is really your goal then wont a 66mm charger get toasty there anyway. I was under the impression that to sit comfortably (reasonable egt's without spray) in the 600+ h.p. range you would need twins anyway. Unless you didn't mind high egt's, which I thought you said you didnt want.

IngrahamS

alright, i think i am going to try the 5's with the 62 and then prolly goto twins next year or so if I want more power. does Anybody have dyno numbers with 5's?
-Stew