• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Which turbo is best turbo?

LeedomtoFreedom

LeedomtoFreedom

New member
Joined
Oct 11, 2017
Location
Ingleside
So I've got a couple options here. My 15g started leaking oil so I swapped back to the little 13c.

Should I

a. Professionally rebuild the 15g

Or

b. Take this opportunity to put something bigger in.

I have most of the supporting mods to put a bigger turbo in.
 
Goals, budget, etc.

If the 15G will support what you want to do, then do that. If you want mOAr hp's, then you might want to start looking for something bigger.

Each additional HP costs more than the last.
 
How far can you take a 15g?

It'd probably be cheaper and maybe satisfy my needs to use it. But I want a big fat turbo because I'll sooner or later be wanting to
 
As said what are your goals. While you can push a 15g to around 240whp past that it really is at the limit, nevermind to do that you need all of the supporting mods to help a 15g get there.

Once you figure out your goals and budget you can decide on what path you want to take.
 
Big fat turbo without all the supporting mods will not be fun to drive.

And dare I saw it, even with all the supporting mods, a small motor/big turbo isn't really always the most responsive engine to use in daily driving.
 
Interesting. Food for thought.

I don't really see myself going far past 300hp. I don't think my car will do it. Ole Bessie is worn out.

The turbo upgrade was usually the last thing I did, focusing more on peripherals to make sure it was done correctly.
 
tryingbe said:
Here's a big turbo is too big thread.
https://forums.tbforums.com/showthread.php?t=337827
Click to expand...

It ends up being a light switch. Off boost - no power, On boost *all the powers*!!! Not much in between.

The motor in my wagon really only felt fairly normal once I got variable boost control setup (Megasquirt) - 8 psi base, up to 22 -24, but based on throttle position. That actually feels somewhat normal and progressive. There's still some lag with 400 hp worth of turbo on a 2.3L engine.
 
Best turbo? We might as well decide the best ice cream flavor....... :rofl:

OP, think "time to torque"..... as the goal.
 
Big turbo is boring...until it isn't :nod: mine doesn't even spool fast and I have a header/open exhaust/big cam/advanced timing....spool ain't much to write home about
 
Spool fights between the turbo and the cruise control can be entertaining. I mostly got that with the 16T and the M47.
 
I just look back to that crazy 8 page thread going about spool time in the T3/T4 and I'm trying to think if that's user error to see if I want to try something similar.

When I had the 15g in, it spooled mucho quick. Should I sacrifice spool time for some HP gains ? If I chose the turbo well, getting one not much larger than the 15g, could the spool time be acceptable for the overall flow. What have people typically done before.
 
15G spools fast because it has a tiny hotside. So you get boost sooner, earlier, more often, less lag. Which is better for a general daily driver. The main issue with a tiny hotside is that it limits peak flow. At high rpm WOT, the engine can only force so much air out past the hotside, even with the wastegate open. So less peak HP (usually found at high RPM's) but more usable, easily accessible power down lower in the rev range.

A big turbo won't choke the air flow on the top end, but then the engine can't spool it very easily You get more lag, you have to wait longer as the revs climb, and even then, off throttle to on throttle there's more time. You do get a higher peak HP, but it's not all win-win, you lose low rpm power and throttle response.

Some big turbos can do things to help spool earlier. Divided scroll helps, ball bearings help, exotic lightweight materials in the spinny parts of the turbo can help. As well as having a cam suited for the RPM ranges the turbo will work best at. A high revving cam isn't a great match for a small insta-spool turbo, nor is a T (for Tractor) cam a great match for a big turbo aiming for high RPM dyno queen peak HP glory.
 
So this is what I'm understanding

a. either keep the 15g and be happy with quick spools

b. get a larger turbo and suffer from turbo lag

c. get a larger turbo but spend more time on making it spool quicker? eg. exhaust, intake, bearings, blah, blah
 
You must log in or register to reply here.
Back
Top