because it's difficult, expensive, and they're expensive.

 

i sure hope this clears the radiator tank. so far i have spent at least $200 on crap that turned out to be useless in getting the compressor outlet lined up with the licp and not hit the radiator. i cannot clock the compressor any closer to the engine. even if i trim the ear on the transmission where the mount bolts to, i wouldnt be able to get any sort of bolt in because of the recirc valve.

im going to head to the parts store and see if the lower tank is thinner on a 97-02 mirage radiator. its dimensionally the same as an evo 4 5 6 radiator, but single core. i doubt the lower tank is thinner than the stock evo 8 radiator, but that would solve this issue. my mishimoto 4 5 6 style is going to be too thick to get the dump tubes where i want them.

http://www.atpturbo.com/mm5/merchant...gory_Code=SILB

 

went out and bought a 97-02 mirage radiator. it fits great! the upper hose location is the same as an evo 4 5 6 and the lower is the same as stock. the lower mounting pins are he same but the passenger upper os off a bit, but a new one would be really easy to make. the lower tank shape and size gives a bit more room for the compressor outlet. now the downside is its a single core and wont cool as well as stock. people run half radiators without trouble so i would think it would be fine, but until someone trys it i cant say for sure.

here are pics.

stock 8 radiator, trimmed coupler still hits the tank.



mirage radiator, 1/2" more clearance.



passenger upper mount, new strap to mount is needed but very easy to do.



upper hose location. same as evo 4 5 6 and a strait shot.



my block is filled to the bottom of the water pump outlets so it only has to cool the head and top of the cylinders. so what do you guys think, will it cool good enough on a street car?

 

dood ****ing awesome find. You get Evom member of the week award. Great thinking.

 

poor mans evo 4 5 6 radiator! i bought it local for $139 but ill return it and get a better quality/cheaper one. rockauto.com has a few for like $70+ shipping. if anyone wants to order one, just order for a 2000 mirage 1.8L. i need to sell my mishimoto now, its a nice piece, but just plain too thick for this setup. i want plenty of room around everything as ill be running stock motor mounts and im sure it will dance all over. i dont need a dump tube or coupler rubbing into the radiator and leaving me stranded or chasing leaks.

 

I don' know, is this right that a 1.05 A/R divided T4 is smaller than a .81 A/R open T4? Doesn't A/R still apply? If they are both T4 they should have the same R (or close). So the bigger A/R would have more A, more total cross-sectional Area at the "nozzle". More A, less back pressure, I would think. I wish they would just give a number for "A" like Mitsubishi does (and Holset) and be done with it.

 

N2oiroc,

You have a 8374 right? which is bigger in overall size than the 7076? The 7076 should it fit better?

 

A/R is just a relational measurement. There are more to turbine housings than just A/R. I have both of the turbine housings that were used actually on my shelf, but before I even take pictures... Boundary layer. A t/s housing has more surface friction because it has 30% or more boundary surface area which for the same "area" (which relates to the a/r in our case) means it has less mass flow.

A/r is measured at the inlet, and the centroid of the inlet (respectively) it does not correlate 1:1 to the volute cross sectional area.

 

Yes its an 8374 which has the large compressor housing along with the 9180. The 7670 and 7064 use a smaller compressor cover and should take much less effort to fit.

 

Exactly! I'll take some pictures of the setup...i will be using a Evo 6 Koyo rad... Let's see how it goes...

 

More boundary surface area, yes, and more drag on the gasses due to that, yes. So if the A's were equal and the R's were equal, and the turbine wheel and turbine outlet were the same, the divided housing would have more back pressure.

The "A" should be the cross-sectional area at the start of the volute. In this case the "A" of the BW should be about 30% more than the "A" of the PTE, unless the R is quite a bit different. Seems like nobody ever gives an "R" number, so from a/r it is hard to get a handle on what the "A" really is, unless specifically stated by the manufacturer, as done by Mitsu and Holset. If the BW housing has 30% more internal skin area, but also has 30% more "A", it would not be obvious to me that it has more back pressure than the PTE. Seems to me they would be pretty equal, so if it's true that the PTE has less back pressure, I would like to understand why. I don't know what the turbine wheel exducer diameter is of the BW, but it is likely about 2mm smaller than the 66mm of the PTE. That could be part of it. Anything you can show with pics or measurements on the housings you have - would be cool!

 

The A/R also doesnt take away for the divider wall taking up some space. Thats why even the 10.5cm twin scroll evo housing isnt all that much "bigger" than a 7cm single scroll DSM housing.

 

Well if that's the case, that would certainly explain a lot of it. It seems wrong though. If the "A" is measured as if the divider wall just wasn't there - that is pretty sad. The divider wall is there. "A" should be the cross sectional area that is available to gas flow.

 

This is false.

I have a 9.8 housing chopped up and the volute area where it first meets the scroll is in fact very close to 9.8cm^2 between the pair of runners. The A/R of a Housing ONLY counts the flow area and the divider IS NOT part of that area counted.


If you want to compare powerbands between single scroll and twin scroll. Multiply the divided housing by 0.6 and you have the roughly equivalent open scroll housing AS FAR AS OVERALL POWERBAND. This is strictly based on some SAE papers I've come across addressing this exact issue.

Thus, a 1.06 A/R T4 divided housing will have a similar overall power band as a 0.64 A/R T4 open scroll housing.

 

what would a t4 1.15 and 1.32 compare to in open scroll??? and if your going that big ''1.32'' is it even worth it????