I was hoping to get some advice on turbo choice for 500ish kw (670 hp) on my 2.2 build , initially was going to go with the EFR 8374 and hope for around 450kw however with everything else pretty much there to push the car further i decided it was best to go a turbo that will comfortably get me 500kw

The plan was to go with the EFR 9180 to comfortably get me the goal of 500kw however i have now been looking into the 8474 and am wondering what the better option would be for me.
Car is primarily being built for roll racing really and while i have power in mind i would also like as best response as possible as well.

As far as I am understanding the 8474 may be a nice in between of the 8374 and 9180 , giving me around the same power as the 9180 but better response .
with the 8474 being smaller than the 9180 im assuming it will be on a lot sooner and have been told it will flow more than the 9180

car will have a built 5 speed gearbox with a 4.08 final drive , with this final drive and being a 5 speed thinking I might want all the response I can get and hopefully roll from 2nd rather than 1st when racing so its a bit easier on the box

any insight into the comparisons on these turbos and power / boost info would be great
thank you

 

I can say the 9180 is the same basic turbo I have before I made it a 71mm. Its basically a s369 which will do well over 850hp not sure what kw that equates to but on a 2.2 would be a good choice. I have heard that the 8474 people do like more, but Idk. If your looking to make 500kw then why don't you think about going smaller? There are plenty of smaller frame turbos that will get you there and be a good fit for the 2.2. It seems like a lot of turbo for a lower power goal when both those turbos will do well in the 800s.

 

hey bro , the 9180 is good for more power I think your right , however the 8474 I believe is good for just around the 670hp, it is smaller than the 9180 so I am thinking it will be a much quicker responding 670hp on a 2.2 than what the 9180 would give me
the 8374 I believe is even smaller than the 8474 but only good for around 620hp I think

 

The EFR 8474 has done 810 whp on a 2.2L and 805 whp on a 2.3L. I think your numbers are pretty low..

 

in that case seems like im going to be a lot better off going with the 8374 over the 8373 or 9180 for

 

Either way they are both bad *** turbos. 8374 is rated from 500-800hp and is 79 lb per min. The 8474 has the same hp range but flows 95lbs per min which is basically the same as the s369 only ball bearing. You are going to be fine with either or but honestly if your goal is 650-750hp i would stick with the 8374

 

the goal is 670 hp , have been told by my tuner the 8374 is only good for around 620hp but can maybe get closer to 650. not sure which one would be more responsive between the 8374 and 8474 but think the 8474 might be good for that little bit more power.

 

I have the 8374 with the small T3 internal wastegate housing and have made 680 at the hubs (Dynapack) Have trapped 148.75 mph as best and 9.641 as best. E85.

 

Don't suppose you monitor back pressure or turbo speed do you? Curious to see results as i'll be on 8374 T4 IWG soon enough.

 

Yes I did, but it was years ago... I think turbospeed was about 120k. Backpressure was more than 3 bar (maxxed out sensor) but I think the culprit was that my exhaust flex had collapsed inside and I havent measured backpressure after I replaced it. Think boost was 2.5 bar falling to 2.3 bar towards redline.

 

it must be nice

 

What do you guys think about the 8474 with internal wastegate ?

I have been chatting to the supplier here in South Africa and they say the internal gate is a better option, helps spool quicker. Will be T4 TS hot side.
My mani is already set up for external so will just need to block it off.

My only concern on the internal gate is that I have seen some housings crack on the inside around the flap.

My car is a 2.3 and power goal is around the 650whp mark.

 

Stay external. You will have way better control of your boost control and like you said it won't crack. That and the fact you can run any wastegate pressure you want. Downside to it is yeah it will cost a little more, but in the end its well worth it in my opniion.

 

Yeah don't go internal when you're already set up for external. The Borg IWGs are really good, but that 74mm turbine would probably do okay at 650whp. I've never really heard of them cracking, though. Overall you'll gain a bit more top end power from the bigger turbine and gain a bit of power from the lack or recirc. I can't stand dumped gates, but that's just me.

 

I made 511kw on a 8374 internal waste gate on e85 once at around 34psi

440kw on 98 at 29psi