88CRXHybrid

What does the divider do in a tangental divided exhaust housing? Is there any benefit to having one as opposed to undivided housings? Which T4 housing would you recommend that would be on a 500hp street driven T61? .70 divided or something bigger like a .81. When could I expect the .70 to start spooling up?

88CRXHybrid

anyone?

earl

IMHO, there's no benefit to the split housing. Originally built for low rpm diesel trucks. It should spool in a minute or two Sell me the T-61 when your done with it.

BlueShadow

I believe in "Maximum Boost" it states that a divided housing would be benificial for large displacement engine or was it a V6. I cant remember but it goes something like that.

Xerxes

I read in another thread (who knows which one) here on honda-tech a few weeks back that the divided thing is supposed to be used such that half of your cylinders go to one side and half the cylinders go to the other side, like with a v6 or v8 etc..

-Xerxes

ATurboCivic2NV

the aem civic uses it and some other top drag cars. i imagine it cant hurt you using it, except the cost

88CRXHybrid

About when would a t4 .68a/r undivided turbine housing with a 11degree clipped p trim turbine wheel start spooling and reach full boost at?


[Modified by 88CRXHybrid, 3:49 AM 3/26/2002]

earl

4000 to 6000 would be my guess on start to full boost. .68 a/r in a T4 housing is a fairly large exh for the street. I think it would take some major heat (NOT FLOW) to get it moving. Remember, heat, not flow, is the energy that spins the turbine wheel. ( U agree, Blue Shadow?)

Dee

Ok.. this is with HKS housings (O-trim blade) on an SR20DET.

AR.40 3000rpm
AR.48 3600~4k rpm header primary size and port job plays a factor
AR.50 3800~4200
AR.58 4k~4400
AR.64 4200~4800
AR.70 4500~5k

All cars used 76mm DP and 76mm or larger exhaust with test pipes. This is from three different cars with various levels of tune. The AR.40 housing was used on a relatively stock 180SX and the 57trim T04E pulls really strong all the way to the 7800rpm rev limit.


[Modified by Dee, 12:34 AM 3/26/2002]

Geovannie

What about the turbine wheels itself. P Q O etc. Can somebody explain these.

Dee

The ex blade trim works exactly like the compressor trims. The major and minor diameters increase as you go up a step. The N trim is the smallest T4 and the Q is the largest. N trims are used on twin turbo V6/V8 setups and small displacement 4 cylinders(less than 1.8liters). As you go up a step in ex trims the effective power band of the engine moves up also. Most street 2.0liter cars stick with O trim blades while trailer queens will be better off with a P trim if they have the proper setup. Rotaries and egines larger than 2.5liters love the Q Trim when used as a single since they produce excellent ex psi. Most of my RX-7 friends use Q trim blades since they all rev past 11k rpm and use LOUD *** hell bridgeported motors.

A street driven drag cars in Tokyo (North Saitama) area used a P trim AR.58 ex housing mated to an HKS T04S(similar to the 60-1) to make 493whp @ 1.5bar(22psi) on a 2.1liter B18C-R. The car ran a traction limited low 11sec 0-400meter(1/4mile) before the owner wrecked it street racing thru the mountains while drunk. The effective power band was 5200rpm-9500RPM. The car was slug a below 5200rpm. Compression was too low (8.3:1) and the cams were too BIG !


[Modified by Dee, 8:54 AM 3/26/2002]

Geovannie

Dee thanks for all the info.

Dee

no probelmo but I was hoping the other guys(Art, Dustin, Mark, Earl) would add a lil' more info to my post!

88CRXHybrid

I will probably be using 9.5:1 rollerwave pistons. The next step smaller T4 housing is a .58 which will probably run out of steam at 9.5K, right?

Dee

Once you go above AR.58 the car will be a slug on the streets until you hit your effective power range. This is why street driven cars that rarely see track time should stick with T4/T3 setups. The T61 coupled to an AR.82 T3 ex housing (and atleast stage 3 blade) would be a good hi-revving street/strip setup. If are planning to do a lot of strip time then go with the housing that is one step larger than the .58 but do yourself a favor and don't waste your time playing around on the streets.

Geovannie

What about keeping the .58 but with a big wheel like a Q? Switching turbine housings is cheap, but how about switching turbine wheels?


[Modified by Geovannie, 2:32 AM 3/27/2002]

88CRXHybrid

I didnt think a T3 housing could go on a T61. Is a T3 .82a/r about the same size as a T4 .81a/r? My hp goal is 500-550. I know that I will need a large turbo (T61) and will not be hitting boost during normal driving(before 3K). I am alright with that. So I am looking for the most track HP. I already have a 3" thermal exhaust so that aught to help spool up the turbo.

Dee

If you switch the housing to T3 you have to switch the blade also. Changing to a Q trim would only increase the "bog factor". Does everybody remember the light Green JDM S13 Silvia from Florida that was in Stupid street a couple years ago? When Ski(the owner) was Okinawa he was using a P trim AR.84 on his CA18DET. That thing didn't make any power until 6k+ rpm and boost didn't exist in first gear. 500hp can be had with a 60-1/T3 AR.82 stage 3 or 60-1/T4 AR.58 @ boost levels of 18~22psi. I will be using an HKS T04S(60-1)/T3 AR.63 (might go to .82) stage 3 to get the 450~480hp that I want.

T4 AR.84 is for rotary engines with stock to mild port jobs and 6clyinder engines over 2.5liters that aren't built. Once again, rotaries and 6cyl~ engines produce lots of exhaust energy so the larger housing spool with ease on these motors. If you are not going to build a full race 4cyl engine that is larger than 2.5liters then you need to keep the housing size under AR.64 and use an O or P trim wheel.

Does the T61 use a T3/T4 or TA45 center housing? If you already have the turbo can you post a pic of it?

88CRXHybrid

No I dont have the turbo yet, but I have done the math(compressor mapping) and know that the T61 is the most ideal choise by far. I talked to Viren(b18bturbo) and he agrees with me that a .58a/r will run out of steam up top with my high HP setup. We also aree that a .68a/r and 11degree clipped P trim wheel would be idea for my setup with HP goal in mind. Do you agree? I think the T61's center housing is a TA45 because I have never heard that it was even an option of using a T3 exhaust housing.

Dee

Since it uses a TA45 center housing I guess your only option you have is to go with the AR.69 ousing. Did you look at the 62-1/T3 AR.82 setup?

Ask Viren if the T61 will mate to a T4/T3 center section.

TA45 center sections are of the big shaft variety with a Mitsubishi style clamp but the picture of the T61 on Turbonetics seemed to use a normal T4 housing. Big shaft is the way to go but T3 blades don't have that option !

Geovannie

Dee, how does a 60 trim compressor wheel compare to a 60-1?

How hard would it be to downgrade wheels. is there any machining required to downgrade from a Q to a P?

Dee

The 60-1 flows more than the 60trim T4 and will have more topend pull.

To go from P trim to Q trim the P trim housing can be bored to fit the Q trim blade but in order to downgrade from Q to P a new housing needs to be purchased!


[Modified by Dee, 11:37 PM 3/26/2002]

Geovannie

Thanks again Dee.

Dee

no problemo!

Slightly OT: I wish HKS and Garrett Japan would use the name AR #'s as Garrett USA... !