Mr. Axe

iTrader: (1)

First of I need to say thanks to all of the members on this wonderfull forum.
Just got my Ls1/T56 Monte Carlo SS started (it runs great) I could not have done it with out all of you. TANK YOU ALL VERY MUCH.

Plans for the future is to build a turbo-LS1. Will most likely go with the Combination Motorsport aluminum Pro Street 430 cui.

So my question is this: How will the Garrett GT60 Garrett GT60 info work on the original 346 cui? I know it will not work great, but will it work at all??

Resaon I ask is that I got a good deal on the GT60, but will not start working on the 430 cui before next year. And I only want to buy one turbo, not one for the 346 cui motor and a new one for the 430 cui.

I think most of you will say that I should wait and not build turbo before I get the block to support the airflow that the turbo needs, but I will not do that.
So do any of you have any thoughts on how the GT60 will perform on the stock 346 cui?

Thanks,
Michael from Norway

bigturboz28

I have a GT42 (102mm) on a 346 and it spools to 10psi in about 4000-4500 rpm. I would guess the GT60 would barely build any boost if at all with only a 346ci. Isn't that turbo rated for like 1500 - 2000 hp or something like that??? I think if you want any boost down low at all you either need more cubes or a smaller turbo.

Mr. Axe

iTrader: (1)

Thanks for the quick reply.
You are right about the hp rating on the turbo. And the stock 346 is probably to small, but from what I've calculated with the stock 346 it shuld flow around 68-75 lb/min with 10psi at 6500rpm. That gives me a pressure ratio at 1,8 and with that I shuld manage to stay within the surgeline, but as you said - will it build boost at all?

I was looking at the same turbo you got, but with the 430 cui engine that turbo is going to be too small. The 430 cui engine will flow atlest 130 lb/min at with 20psi at 6500rpm.

I was also looking at the GT55, but can't find any compressor maps on that and very little info. I've read all the post that the member 2000 Tran Zam (408 Stroker with GT55) has posted and I just love that car. So that is an option, but I won't go any smaller than the GT55.

Back to the GT60, if I'd used the smallest exhust housing would not that help me build boost a bit earlier - maybe spray with nos?

Thanks,
Michael

deviate42

iTrader: (2)

i think it wouldn't be worth the headache. If i were you, i would buy a cheap t70, 67 for the 346. when your ready, sell it and setup up to the gt55/60. your not out much money and you have a proper turbo setup.
you will have way more fun for that year with the 346 than you would slapping a gt60 on it and adding to your 4 letter vocab. my .02

NA$TY-TA

iTrader: (21)

Yeah that turbo is way to big..... its a 106mm turbo....... people have lag with a 88mm on a 346....... DAMN........

Mr. Axe

iTrader: (1)

Yeah, I know it will LAG on the 346, but can I use it at all? Couse it will fit the 430 cui perfect (I think).

Building turbo-headers and tubing for a small T70 or similar this year is not an option, couse then I'd have to build it all again when I get the bigger turbo for the 430 next year.

Would be nice to fit everything this year with the GT60 or GT55, and the next year just drop in the new block and turn up the boost and fly

Congrats on the car NA$TY-TA, been following the build up. That car looks really sweat.
Probably don't need to say this (everybody else is) BUT POST SOME MOORE VIDEO

Thanks,
Michael

NA$TY-TA

iTrader: (21)

If your really set of building it for a 430ci motor then JUST do that then instead of wasting time and $$ trying to get it to work on a 346.
I know N/A sucks but think of the big picture..... when its all done a YR from now it will be so worth it...... believe me ive done just that..... mine has been gone over a YR now.

Thanks for the compliments...... more vids this weekend.

Kyle

Spenser309

twins would be alot easier for this predicament, One T76 now and another T76 later?

Mr. Axe

iTrader: (1)

Doing one turbo now and add one later has crossed my mind, but as far as doing 2 downpipes and 2 mid-sized turbos and the extra plumbing to the intercooler it will be very tight and alot of heat building up. Moore easy to fit one (BIG) turbo than 2 mid-sized.

Thanks for all input and suggestion, but in the end do you all think the big GT60 or GT55 will slow down the stock 346 or will it run as normal and maybe build SOME boost before the redline?

This is my first V8 turbo-build so I've never used so big turbos. Have built some smaller Volvo 4cyl turbo-engines, but thats another world when it comes to turbo-size.

I hear what you say NA$TY-TA regarding building it all at once, but it so happens that I got a killer deal on the GT60 and I dont have the money for the 430 before early next year. And it would be great if I could start the turbo build now and drive with it. Then just drop in the new block later. But if the big turbo would "hurt" my engine then I'll wait.

Thanks,
Michael

ABeasst

iTrader: (5)

how much power or ETs are you trying to make/run? I mean a lot of HP can be done with less turbo and motor

Mr. Axe

iTrader: (1)

As much and fast as possible....of course

Frost

iTrader: (45)

Gonna have to rethink that tranny setup for the big-inch setup with that turbo too...

Mr. Axe

iTrader: (1)

Yeah, i know...

Do you know how much a T56 can be made to handle if you were to put 4-6000$ in it?

I will not go automatic ever

sb427f-car

You're over in Norway? I'm assuming that you're going to be surprising the hell out of a lot of euro sports car owners aren't you??

RyanJ

If you got a great deal on the GT60 then I'd sell it for a profit and buy something else. Personally, I like the idea of small cubes and big turbos for big power. You can do the math for a 427+ cid LS1 and a GT60 on www.forcedinductions.com. Same for a 346 w/ that turbo. I'm pretty sure that GT60 will eventually spool...maybe, but I'd start looking at nitrous kits if you really want to put it on. At lower RPM's your gonna be well beyond the surge line/limit.

Personally, I'd build one motor...346, 366, or 370. Then build a kit for a T6-frame turbo. Start small...then get bigger. w/o many changes you could go from like 74mm to 106mm.

Mr. Axe

iTrader: (1)

You are absolutely right, I hope to kick the **** out of every euro and ricer style cars over here

Here is what I'm up against:
Bmw M5
M5 on track
+here is a couple of 1000hp Supras.

I get what you mean, and thats probably the way to go.

Thanks for all the help and if anyone has any more info on the GT55 or GT60 -keep it coming.

Thanks,
Michael

smokinHawk

iTrader: (48)

why do you need such a big turbo i think a GT47-88 would be more then enough.
if you got the 60 for a good price then sell it and make a profit like someboedy else mentioned.


unless your shooting for over 2000HP i wouldnt use that big of a turbo.

Mr. Axe

iTrader: (1)

Well I don't need that big of a turbo, don't really need turbo at all - but damn it's fun

Can't sell it, I'll get the good price if I use it.

I was just thinking if a GT55 would work on a 408 and ls1speed.com uses a mid-frame 88mm on a 370 then it would probably work with a GT60 an a 427+ cui.

Keep all your opinions coming, and if any of you have any facts and compressormaps on GT55 I'd appreciate it - finding very little info an that turbo.

ABeasst

iTrader: (5)

a GT55 is plenty for a 427, hell even a T88 on a 408 can make 1100rwhp. So unless you want to make 2000HP I wouldnt use it plus you could get a 370 or 408 cheaper than a 427 and use a smaller turbo.

nz12's

iTrader: (4)

how about a Gt-40 on a 355? as a rear-mount?