Currently I am running the sc61 with a t4 .58 a/r trim. (see this for full set-up: https://honda-tech.com/zerothread?id=626917) It put out roughly 423whp @ 20psi. I was planning on having another head done with OS valves, but I never run 20psi on the street so basically I'm staying with the same set-up but adding a nice sheetmetal intake manifold on in the near future.

Since my car is garaged for the winter, I was thinking of swapping out the a/r trims. Would upgrading to the .68 a/r trim be a good idea since I'm looking for a bit more power or would that be overkill on the street? I would like to hit 500whp but if I don't I realize the world will not come to an end. Remember I have a heavy *** piglude so I'll take all the power I can get since I dont have a hatchy. So should I stay with the .58 a/r and crank up the boost a few more psi or add on the .68 a/r to gain a bit more power accompanied by the new IM?

 

The .68ar is really the best T4 housing for most high hp/Drag Honda's.

I will be using a .68ar all GT SC61 with my 84mm GSR, and from the research I've done it should hit full boost around 5K with my 9.3cr.

Since the H22 has a much larger bore, I think the .68ar would be fine for your goals, especially if your trying for 500whp.

What RPM do you get full boost with the .58ar housing?
...And damn I love your dyno vid!...

 

your only at 20 psi with 423whp i would just up the boost your good up to 28psi and its not going to take 28psi to make 77more whp
you should have 500whp by 25-26psi

the smaller turbine give you a much more usable power , on a low revving engine like the h23 , dont for get we are not revving to 8000+rpms

what fun is it getting full boost at 5500rpms and shift at 6500 or 7000

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DLB1994 &raquo;</TD></TR><TR><TD CLASS="quote">
the smaller turbine give you a much more usable power , on a low revving engine like the h23 , dont for get we are not revving to 8000+rpms

what fun is it getting full boost at 5500rpms and shift at 6500 or 7000</TD></TR></TABLE>

Yeah thats true.

I had an SC50/.63ar on my stock ZC, and it was basically that. I had full boost at 5.5K and had to shift before the stock revlimit of 7.5K.

Pretty much on every shift, I slammed into the revlimiter because it kept wanting to pull up higher in the RPM's.

The SC61 is good for 30ishpsi...so yeah I would just up the boost.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DLB1994 &raquo;</TD></TR><TR><TD CLASS="quote">your only at 20 psi with 423whp i would just up the boost your good up to 28psi and its not going to take 28psi to make 77more whp
you should have 500whp by 25-26psi

the smaller turbine give you a much more usable power , on a low revving engine like the h23 , dont for get we are not revving to 8000+rpms

what fun is it getting full boost at 5500rpms and shift at 6500 or 7000</TD></TR></TABLE>


listen to ol' DB. why would you run a turbo @ 20 lbs of boost thats made to turn out 28 lbs of boost?? you should be seeing over 500 to the wheels with a 2+ liter motor with that sc61. never move to a larger turbo until you have pushed your current one to its limits.

 

Well we ran out of time on the dyno when we tuned it before. Next trip this summer I plan on upping the boost and running straight c16.

Just wanted some opinions on the matter, I figured staying with the .58 was the way to go. Thanks guys.

 

So how was the spool on the turbo? I'm kinda wondering what to expect with my up and coming GSR setup.

 

The spool times are not bad at all. Boost usually kicks in right around 4kish. I had a ball bearing t3/t04e before and I'll tell you the spool times were rediculous. Traction was horrible in 1st, 2nd, and 3rd gears. The tires still break loose in 1st, 2nd and 3rd but not nearly as bad as before.

 

I am going to be running the .58ar on my B series. I really havn't heard much about it. Info for T4 hondas is really scarce but I am going to give it a shot anyways. I know the .68 is already proven so if this doesn't work I can always upgrade. I would keep ur .58ar for now and crank up the boost, I don't think it is holding back top end flow at all on ur set up. I think that is all from the head.

 

i upgraded to a .69 t4 turbine i think its a O trim wheel with the old school 60-1 comp ,ill see how the spool is on this soon

 

what turbine trim are the SC turbo ?

 

I believe it is a p-trim.

As far as head flow is concerned, I don't think that is too much of an issue. Unfortunately I had Gude do all of my headwork, everything looks good and from the dyno charts/graphs everything looks like it is flowing quite nicely. I was planning on going with a portflow one with OS valves this summer but spending another $2k for a little bit more power that I will hardly ever use is just kind of a waste of money now.