iansane

iTrader: (1)

So I've been reading turbo sizing for awhile and spent the last week or so trying to read formula's and flow numbers on what I should build for this thing and I'm still not too sure. I've got a roller 305 with an LT1 cam and Holley Stealth Ram that I'm starting to put together a setup for. I'm looking at a Master Power turbo, the T61, "O" trim. Looking at the compressor map:


I'm only looking to put 8-10psi through it which seems like it's right at the bottom just above the 70% efficiency line. Is that good? Someone on the turbo forums suggested a lot larger T70. Would that be a better idea?

84bandit

the smaller turbo will have better street manners, and make boost faster. what the car going to be used for? power goals? the larger turbo would give you more room to grow with your motor.

iansane

iTrader: (1)

This is for my vert. Street manners aren't a huge deal to me. I've always been willing to deal with a harsher vehicle than most everyone. I don't have specifc power goals, maybe to be able to take my mom's '07 vette. I don't have huge plans for this motor, the most I would ever do would be a set of vortec heads and that's not very likely.

junkcltr

iTrader: (1)

A 61mm inducer will do it if all you are looking for is to beat a new vette. The biggest problem will be setting it up for traction. If you can do that then you will be quicker. 10PSI won't do it. You need more. Spray it with Ethanol or Methanol under boost.

WheelsUp84z

iTrader: (2)

I read your post on TTF.com and i would have to agree with the responses here and there. a Master power t-70 or even a 60-1 or 62-1 should be just fine. If you wanted, go with the MP GT45 and it should transition over to a 350 as it is just a little bit bigger than the t-70. Also since you probably wouldnt want to spin the motor much more than 5500-6000 you should get the .68 A/R or even the .81 Tang. housing so that it will spool quick and get full boost sooner. also at 10 PSI the turbo should be around a 1.68 Pressure ratio, which should be clost the the 76% efficiency zone @ 30lb/min+

BANDITSBC

well i've got the exact same scenerio here, a 90 305 and the funds are extremely low, i just won an ebay t61-chinese turbo that dad bought me for xmas. and moms getting me a waste gate and bov- i figure if i'm gonna wreck something on my first turbo motor might as well make it not hurt so much. i see there's a 60-1 on ebay right now rebuilt cheap(250). well i won't have mine done until close to spring, so i can't help alot. but i think a t61 or 60-1 will be good for it. good luck

iansane

iTrader: (1)

Alright, looks like T70 here I come.

PETE

iTrader: (1)

the 60-1 and the 62-1 use the same 60mm wheel.

The 61 is a great turbo as well and has been designated as a 65 by some manufacturers when using the 4in cover.

What heads are you using and what converter will you be spooling it up with is a bigger concern than how much the gauge will read.

Example stock 305 heads may read 10 psi, but throw a set of afr's or vortecs on and it will show less boost but move the same amount of air.

Using a 70 on a converter of anything less than a loose 3200 on an 8 cylinder probably will **** you off.

A good 10" converter on the 70 with a .68 would snap it up quick depending on the turbine(ie p trim or q trim). It does take a bit more energy to get the Q going though....

I've had precision turbos and turbonetics. To buy one new I usually pony up the coin and get a turbonetics turbo....

JMO

Jeremy_84_F41

iTrader: (3)

I haven't seen a map for the Master Power T70 but I am pretty sure it has a smaller than 70mm wheel... IE, it isn't going to be as big as a Turbonetics T70. There are a few Mustang 5.0 guys running the MPT70 with 5-speeds that seem to like it.

iansane

iTrader: (1)

I don't mean to be an a-hole, but it's not an auto trans. It's a t56, says right below my user name. And they're stock heads. I said my only mods were HSR and lt1 cam(enginewise). I would assume that flow characteristics like a bigger head would flow more, while showing less psi are absolutely bare basics that anyone doing research on turbo setups would find out. But I guess on this board you have to assume everyone asking a question is ignorant. I appreaciate the input!


Jeremy,

Yeah, on theturboforums the guy suggested the mustang comparo. Do their 5.0's flow around what a late 3rdgen 5.0 flows?



See, that just looks real large to me but I obviously can't compare.

PETE

iTrader: (1)

No problem! I guess some people on here are used to reading minds on an owners particular setup. We have a lot of talented people here......

Without putting the info needed in your post why would people assume to use the info in your signature or profile

iansane

iTrader: (1)

Maybe because I said roller 305, HSR and it says both of those under the user name, and this is a 3rdgen board, so...

Either way, a simple, "Is this for the 'bird in your profile?' would've done better than suggesting things for all the options available.

Seriously though, thanks for 60-1 and 62-1 info. That's stuff I was ignorant to.

PETE

iTrader: (1)

Really, not jumping on your case. There are just too many threads put out there with to little info in them. IE Something like yours then it turns out it's theoretical cause the car or engine or both for that matter do not exist.

Also I rarely update my stuff and rarely look at anything other than the posted question within the topic.

Anyways, on the stock headed 305 with a stealth ram you have a few options.

Here are a few: either a 61MM with a larger exhaust housing(.9x) and a larger turbine(keep you from buying tires every 3 months).

A 66mm wheel with a p trim turbine and a .6x housing

A ball bearing 70 with a p trim turbine and a .6x housing

If you are looking for a killer street for that setup but may run out of air on larger heads is a BB 63mm with a Q trim.

I've used a 60-1 which would run to 30psi but wouldn't really plant you.

A pt- 51 which I believe is a 59mm wheel and a gt350 turbine, decent but wasn't satisfied. A te-44 again same wheel with a smaller turbine(like this one snaps up quick on the V6.

And my favorite was on my last TTA which was a BB 61(aka CPT-65) with the larger 4in cover and a .63 housing. Truly was a great turbo.....


Good luck with your choices!