turbo lag/spool with holset turbos.
 

Hello I'm looking to turbo my ka24,

I'm looking at the holset turbos. My question is what turbo do you guys think I should use if I'm looking for 250 whp with room to grow.

Preferably t3 flanged.

Also I'm looking for a turbo that starts spooling around 2.5 to 3k rpm.
This is for mpg efficiency.

I've tried searching with not much result.

Let me know your recommendations .

I personally like the hy35!

Could you tell me a little bit about this turbo from your perspective.

Like lag
Specs
Clocking.

Any of your personal prefrences.

I recommend buying another car known for mpg efficiency, and use this one for fun, when fuel efficiency is not a problem aka when you earn more money, or when you dont need to daily drive it (seriously).

I knew somebody was just gonna have to post this.

Just because I want to get good gas mileage and also be fast doesn't mean I'm broke , need a better job or get another car.

I will find what I'm looking for but thanks for helping out tho.

twin-scroll t3 HX30. It's about the size of a GT28R, spools super fast with twin-scroll, and makes 350whp at 15psi on a decently setup engine. clocks any way you want it, and should spool to full boost by 3k rpm.

why would you even consider a holset for 250whp and unbuilt engine... that is just asking for disaster. a holset could easily flow double your hp goals.

how about something realistic like a t28

Thank you! This is the type of answer I was looking for. Estimated, I should start spooling around 2500? Give or take?

depends on the AR of the hotside.


I'm telling you, you are going way overkill on a holset for 250 hp.

Is your KA even built?

Get a gt2860, or T28. Spool quick 250whp no problem easy fitment

I think you missed the part were I said "with room to grow".

It's okay tho.

Also a t28 won't hold boost to red line on a ka. As far as I researched.

Please let me know if I'm wrong.

gt2860 will no problem

I cant adjust boost with holset turbos? If it makes 350 on 15psi I can't lower it to like 10psi or lower?

Maybe I'm missing something.

yeah it's called a wastegate.


I highly, highly, highly recommend that you study up on how a turbo works, boost, AFR's in boost, all that stuff.

cuz if you aren't aware of how to control boost, you are bound to blow your engine up.

and I'm not being a dick, I'm literally trying to help you.

No I get you,

I'm aware of an external waste gate , springs , boost controller , all that. Not 100 but mostly.

I asked because you were saying how holset is over kill. And I figured maybe they weren't like a normal turbo.

Can I just run 10 pounds on that holset to achieve my temporary goal?

Most holsets come internally gated. However, since they were meant for diesels, the internal gate is often too small to adequately control boost. A lot of guys weld the internal gate shut and use a 38mm external. With the right sized external wastegate and spring, you could run 3psi if you wanted.

If you wanted the turbo to start spooling at 3k, an HX35 would work... but that's a pretty big turbo for what you seem to want. They can make upwards of 450whp. Hell, the HX52 *starts* spooling on my RB25 at 3k and is fully spooled at about 4.5k.

you must understand that 10 psi of boost is not the same on every turbo.. 10psi on a k03 might net you like 180whp, but 10psi on a HX35 might net you 300+

If it was ME, and I was set on getting a holset, I would get a hx35, run like 6psi tops until my engine was built. 10psi your engine might blow, 10psi I gaurantee you will spin tires in low gears

and there is a reason for that : everyone would rather have a car that does not eat fuel AND go fast AND look good AND be practical AND be cheap and so on.

Fact: it does not exist.
You need 2 cars. Been there, done that. Got a comfy one that burns no fuel and has room, and a heavily modified S13. Before that i just had an average S13 that would still eat a lot of fuel, tyres and needed frequent maintenance because of the mileage.

You can believe the opposite, but then dont come crying, esp as you dont know anything about these particular engines, or the downsides of adding a turbo (or getting more performance).

No offense but it means you dont know anything about cars. You need to get real. You are free to believe in the holy grail, however that wont make it appear.

No you wont ... you will find people telling you what you want to hear though.

The same kind of people who will surely go missing when your engine blows, or when you end up with worse mileage than ever.

This really is occuring so often it becomes boring ... you are all so predictable.

I was refering to this post

To start this off, I do know about cars. Not much about turbo but in general I do.

This would be my first turbo motor to own. I've seen threads of people getting 25 to almost 30 mpg being turbo. On a ka.

So don't tell me it don't exist.

And to end this , I started this thread wanting 250 HP to the wheels . I understand if I would have wanted Fully built 300 HP+ and wanting great gas mileage

even if I dont get 27mpg I would like to see my options

Power is not the only thing on my mind. I'm just saying its not impossible.

Thank you I will definitely keep this in mind, also on the gt2860 you were talking about is that t3 or t2 flanged ?

The Hy35 is the bastard or most overlooked holset turbo. it has a compressor wheel that is 56mm and supports 60lb/m which is what the 7blade HX35 support, but it's smaller on the exhaust side so it spools way faster than a twin scroll hx35 etc. and will work with any t3 manifold. Perfect for a ka's rev range. clocking, make it fit!

he doesn't need a 60lb/min turbo..... unless he wants like 450+ hp.

Gt2860 is T25 flanged.

Also, You can actually get better MPG in a turbo car than NA if you drive it right

Nice, good Shiit , I actually did see a build thread on this turbo. By when you.think it would start spooling.

I wanted to avoid t2 flanged because of upgrade later in the near future. But maybe I can just use an conversion adapter .

When you say driving right you mean staying out of spool?

Yeah they do exist but are not making the WHP numbers you want. They are making about the same as a stock blacktop SR.

He's telling you the truth and is trying to help but you're ignoring comments you don't want to hear.

Hy35 does not spool faster than a twin-scroll hx35 that is on a twin-scroll manifold.

This thread needs a lock. OP, do some searching, all of this info is all over the net.

agreed. the OP is all over the place doesn't even know what he wants and doesn't have a clue about turbo setups or half the stuff involved with turbo'ing an engine.


you just wanna slap on a holset... what kind of holset the op has no idea.

just go research more dude and come back when you have an idea about whats going on

All that dude was saying was to get another car , mpg suck with turbo , I don't know nothing , and that's about it.

Ok so do you know what else you need with a turbo? or you think just get the turbo, slap it on the stock exhaust magically and that's it?
Also just gonna let you on a little secret dude, Holset + 2.5K rpm spooled is called fantasy land.


How are you going to tune it
what injectors do you plan to run?
wastegate and boost psi?
Intercooler with bpv?
oil lines to the turbo, tapping the oil pan / block?

If you plan on just "maxing" the stock injectors, just stop yourself right now and quit.

if you don't know how you are going to tune it ( which i really don't think you know since you didn't know what a wastegate is / does ) just stop yourself right now.


Here is what you need to do dude. Quit looking at cool pics of turbo's on the internet.
Take some time and RESEARCH, and LEARN everything you can about KA-T setups, NA to boost setups, AFR's in boost, TIMING, KNOCK, ETC...
because guess what, if you think you need a holset for 250whp "with room to grow" you have already failed. there are better turbos, that have better flow rates, better compressor maps, Quicker spooling Hotsides, the list just goes on.
And if you only care about spool time, Why don't you research what the hell causes quick spool or slower spools.. Or how hotsides affect Top HP? or anything for that matter.

You could have a HX35 that spools 6000RPM, or one that spools at like 3500 RPM. Go research and find out why.

If you want a holset cuz it's a big turbo and looks like you gots madzzz hp, Don't be surprised when you add a few holes in your block. Start investing in bus passes.



If you buy a turbo before you know what AFR means or what good AFR's are in boost, you have successfully became retarded.

Why you think I started this thread, to try and grab some info. Better understand.

I though you were koo , and appreciated your responses. , nobody can ask anything Cus foos start tripping.

It's funny Cus in person Nissan guys are nicer than the Honda cats But on this forum you guys are quick to attack the ones that don't now much. I knew I should have just waited for a response on ka-t.