Possible dumb question...

Brighammer

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So... I'm fairly new to the diesel scene. Well, the turbo diesel scene. I used to drive old vw rabbits and dashers with the 1.6 na diesel motors.

I was given a 1985 Jeep Cherokee with the Renault 2.1td in it about 4 years ago. I let it sit in my field for 3 years, and last spring finally got it all going and on the road.
Its fairly gutless until you're a bit under way and the turbo starts to spool up. but it takes its time before it starts to spin good. But I've put 10k on it since July of 2018 like this, getting 20-22 mpg all day long. I just figured its how turbo diesels were. Because I heard about 'turbo lag' and I figured thats what this was.

But then i picked up a Dodge Ram 50 with the 4d55t engine in it(and promptly put the engine in my 91 Mazda B2600i).
Its SO much snappier, and you can hear the turbo spooling up and doing its thing as soon as you depress the throttle even a little bit. And its SO much more responsive.

Is there any kind of typical adjustments you can do on a turbo to make it spool up faster?

Whats a wastegate and how does it work? What about a blowoff valve? Is there any good resources I can go to learn/read/view videos about turbo operation?

I know, I know. "Why are you doing diesel swaps if you don't know how a turbo works?"
Well, because I wanted to. :p
 

Shadetreemechanic

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A wastegate dumps excess turbo pressure off the system. It allows for a turbo that can build boost more quickly at lower rpms that otherwise would overboost at the top of the rpm range. If it leaks or dumps boost too quickly it can affect performance.
 

Brighammer

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A wastegate dumps excess turbo pressure off the system. It allows for a turbo that can build boost more quickly at lower rpms that otherwise would overboost at the top of the rpm range. If it leaks or dumps boost too quickly it can affect performance.
Are they typically adjustable? I'd like my Jeep to spool up faster. It doesn't need more boost. It just needs it faster...

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Thewespaul

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Adjusting it tighter will make it open later, so you may get more bottom end but likely more boost as well. Double check all the exhaust and intake connections for any boost leaks, those will mostly affect how soon boost comes in. If your turbo is worn out and has some play it won’t spool as quick as a turbo with tight bearings.
 
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