Compressor .60

58mm inducer billet

Turbine

T4
65mm exducer
.81AR


Initially, we agreed on a 62mm exducer, but he said the turbine I want only fits the 65mm exducer.

Will this 65mm effect my spool a lot compared to the 62mm? I'm going for decent spool, and decent top end, but I have a feeling the 65mm exducer on the turbine is a bit large. i know the top end will be great.. but I want acceptable spool.


thoughts?

Going on a 81mm 10:5 comp lsvtec, most boost on 92 (20 psi), ultimate goal is ~500whp

Thanks

 

The standard T3 stage 3 wheel is efficent to 500hp, the 65mm Stg 5 wheel will certainly push the powerband to the right.

Are you stuck using a T4 flange?

 

t4 anything is going to be laggy on a small displacement motor, especially with a 65mm turbine wheel. and even more so on a top mount manifold.

if this is a street car you're going to hate the powerband

 

its going to be a weekend warrior.

I noticed my t4 manifold's primaries are not as large as other t4 top mounts ive seen.

Also, my turbo guy has a .68ar t4 turbine housing available as well. I'm going to ask him the smallest exducer he can fit in there.

Would a 62mm exducer with the .68ar spool a bit better? Heres a pic of my manifold to show you the primaries. Not the prettiest.

If I can't throw a smaller turbine on there with a smaller exducer, and still have slow spool, I might as well sell this damn manifold then hmmm... I rather not.. but I will if I have to. I just sold my damn ramhorn too, UGH

 

Do you have any more details on the compressor wheel? There's a lot more to it than just the inducer size...

blade count and configuration
blade back angle
hub height
tip height
superback design
what material, 7075, 6061...
forged billet or just a formed billet
point milled or flank milled (point is better)
inducer blade height
blade thickness
hub thickness and taper

is it a custom wheel he designed or is it just a company "shelf" wheel? if he didn't design it then I'm willing to bet it's a Kinugawa or KTS wheel.. KTS is one of the largest suppliers of forged billet wheels with the largest selection on earth. funny story is they supply most of the turbo builders that aren't large companies (turbolab, wicked, and so on)

 

If you're looking for 500whp, I'd just get the 5858. I had a JB unit with the ported S cover and a Vband in/out .82 exhaust. I made 560/405 on 20psi. Absolutely blast on the streets. Responsive down low and held power past 9200.

 

its a KTS wheel

did a bit more reading around, and saw some people with t4 manifolds get decent spool with the right turbine. So i'm thinking a 11 blade billet wheel, 58mm inducer, with a .68 ar t4 turbine housing. I think having the .68 ar housing will help spool big time vs the .81 I was going to choose. honestly I'm stumped between the 7 and 11 blade. I want the 11 blade to be sure I spool fast enough, incase the the smaller turbine isnt enough, but I also want the 7 blade because it flows better top end. I'm not going to rev passed 8500rpms, and this turbo wont go passed 20 psi for most of its life. (shooting a bit over 500whp on 92) I really dont plan to run race fuel or e85 ever. I like pump gas.

what do you think?


also.. I have a t4 to t3 adapter... I don't know if that helps or not.. but it seems it would be a massive restriction around the 500whp level.

 

I went with a 59mm 11 blade compressor wheel, t4 .68 ar exhaust. hope all goes well

 

I need that adapter to get my t4 revhard mani to run one of my t3 turbos

 

Well. I can say without a doubt I don't use KTS. Just in case there are those wondering.

The 65mm Exducer exhaust wheel is similar to a "stage 3" in actual wheel diameter size. Its best if you can be accurate with what exducer you're using. Remember, exducer size on the turbine wheel is opposite that of the actual overall wheel diameter.



Hope this helps to avoid confusion.

 

Sounds to me like you have too much exhaust wheel. The 65mm exducer wouldn't fit into that T4 .68. You're looking at probably a 69 trim 74mm wheel diameter to work with that turbine housing.

When you submit pictures of what you're actually getting, you'll have a better idea as to its characteristics or not.

Good luck to you.