AVB

iTrader: (9)

Unfortunately Precision doesn't make this model w/ a larger A/R so it's either make em bigger somehow or choose something else altogether. I know it'll come on faster than what I have now but will it be a lightswitch and more important, would it cause too much exhaust backpressure at that A/R?


Any info is appreciated..

alwaysinboost

what type of housings are these?
v-band, 5 or 4 bolt?
on center or tang?
divided or open scroll?

you should have no problem sourcing a couple of .81 a/r housings or larger if you like.
they're out there all over the place, just gotta look around...

onfire

iTrader: (17)

Definitely too small. I ran twin 61's with 0.8x AR turbines and would have later tried 1.0x. Try ATP Turbo...they make some weird stuff.

AVB

iTrader: (9)

Hmm.. ATP is like 20minutes from where I work. I'll have to pay them a visit and see what they've got.


I guess this would make it a 5 bolt? (one is actually off the pic)... So far only one's I know are custom units by APS. Which, the units I have are upgrades to their base units.

crashly

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Unfortunately Precision doesn't make this model w/ a larger A/R so it's either make em bigger somehow or choose something else altogether. I know it'll come on faster than what I have now but will it be a lightswitch and more important, would it cause too much exhaust backpressure at that A/R?


Any info is appreciated..
__________________





probaly sort of kinda agree....

i had twin 61mm with .82 a/r single entry on 355 cubes
power started about 4000 rpm.....
dynoed out around 1000 ft /lbs and 770 hp @ 24 psi... at 4000 rpm on stukta dyno
6500 rpm was more ....hehe

so

you got a rocket ship with 408 cubes...
either put some real big gates on it , or get some larger a/r housings

my turbo's where twin gtk 550 's turbonetics ( 61mm )
made max power around 6500 rpm to 7000 ish
std iron heads,
sbc 23 deg

reverse split cam , 256 / 245 @ 114 sep

it had a 10 inch converter ,
and it got pulled to 5700 rpm @ 35 psi boost


keep us updated
cheers

alwaysinboost

are you running internally gated turbos?? cause it looks like it from your pic.

this company may have the housings you're looking for.

http://www.atpturbo.com/Merchant2/me...egory_Code=HSG

I'm not a big fan of them, but if you give them a call I'm sure George can find what you're looking for.

these used to be all over the place, if you look around I'm sure you can find them used. Heck, I have two sitting on the shelf in my garage except they are .63 a/r.

depending on the power you're looking to make, and you budget, you might want to consider the less restrictive 4-bolt off center design... see below for comparison.

AVB

iTrader: (9)

It's actually externally wastegated. I've sent ATP an email so we'll see what they can do. Hopefully, they can do something since it looks like they cater to the Garrett stuff and the unit I'm referring to is a Precision unit.

topend

I run twin 58mm turbos which is plenty on the street. All turbos cause backpressure . In your case with twin 61 mm turbos you will make plenty of power you would forget about backpressure and wonder why u have so much coolant in the coolant reservoir.

AVB

iTrader: (9)

what cubes are you running those 58mm turbos, boost?

On the 61's I'm more concerned with the A/R's of .63 keeping power till 6.5k

ayousef

how about running larger wastegates??

topend

I run 276ci (v6).

I dunno if your turbos will go all the way up to 6500 rpms with your motor. but what i do know is twin 61mm is overkill on the street . so u might have to have short shift , but so what.

chuntington101

AVB 61mm is the same as what the GT35R turbos are. now i know the APS gusy are running those on LS7s and not having any problems., but they are running a 1.06 housing i think.

could you not go for a 0.83??

Chris.

AVB

iTrader: (9)

Chris,

Precision has confirmed that the T3 5bolt flange only comes in a .63. That's good to know it's similar to the GT35 though.

Anyone know what the possiblity of boring that .65 housing out to a .8x would be, or has it been done?

chuntington101

is there any reason you have to keep the 5bolt flange??

and i thought the PTK kit your running ahd T4 flanges??

come on AVB what are you planning??

Chris.

AVB

iTrader: (9)

Chris...

I currently run 66mm T4's on the PTK...

This is for a setup that'll keep the engine bay cooler on my extreme days I play on roadcourses. Along with lowering and moving weight closer to center, it should be a nice improvement. The goal is to find a setup which has the power come on similarly without losing anything I don't already have now. I didn't think it was going to be too difficult but there isn't an existing kit on the market that keeps brake cooling ducts that I could just bolt on.

BLWN1

iTrader: (6)

66s for sale?

AVB

iTrader: (9)

Sorry not by themselves, only with the complete kit..

chuntington101

AVB how about having a word with Nick Yoskin. is there nothing you two could come up with??

also thinking about the heat thing, wouldn't smaller turbos cause more heat?? im thinking there will be more backpresure and the turbos will be heating the charge air more than the 66mm will be.

how about running E85?? just thinking you amy beable to run more power and lower boost. This should help reduce under hood temps a little and put less stress on the cooling system....

Could you not get Nick Y to make you some heat shields??

Cheers

Chris.

Shawn @ VA Speed

iTrader: (3)

you need to get rid of those 5 bolt turbine housings and put on some t4 flange .96a/r turbine housings,can get them from precision all day long

AVB

iTrader: (9)

Assuming these would be low mounted, a small amount of additional heat wouldn't be too bad. A big A/R on a 61 could be better depending on power requirements.

As for E85... since I do DD this thing, doesn't it get crappy gas mileage? I know... The PTK done right like myself, Nick, Kevin and others, is fine for running as hard as you can on the street and the strip. I run it a tad harder..

Nick and I are talking about some ideas and some of his many new options