Uh, no. Headwork improves power everywhere, especially when it's mild.

 

You're going to have a hard time convincing me that this isn't acceptable:
(hustler's old setup at 9psi. IIRC, it's a '99 motor, no headwork, 0.86a/r GT2860RS, AF mani/DP, catless 3", 94octane)

 

Oh its acceptable alright. But that's not the point. If there was another plot done with the .64 on an otherwise mirror-image setup (or that actual one) I'd be a no-doubts believer.

But then we have dems plot, which was done on a MUSTANG with a sorta similar setup but the .64 tater:

https://www.miataturbo.net/dynos-tim...tq-dyno-63068/

 

I assume you're playing devil's advocate? That's a VVT motor and a 0.64a/r on a similar tubular manifold making less torque than Hustler's '99 setup on a 0.86a/r, which helps to prove my point.

There are a bunch of 0.86a/r setups making great low-end torque - my old AF setup and Trey's AF setup are two examples. What I don't see is 0.64a/r setups making a bunch more than the 0.86a/r setups, and certainly not to the extent that SR20 or 1.8T guys see. I've driven plenty of 0.86a/r 1.8 cars, both 99 and 01+, and none of them drove like laggy, big-turbo cars.

I will say that I'd never suggest a 0.86a/r turbo on a 1.6 motor - I've driven one and it was awful. Having said that, though, 1.6 motors are awful too

 

We'll see soon enough hopefully. My current setup is basically the same as Dems + e85.

And yes of course I'm just stirring the pot trying to get a good discussion going on this subject. Who knows, maybe people with dyno plots we've never seen will chime in and contribute.

As for MORE torque, I didn't say that. I know it won't make more peak torque than a .86, I'm saying it will probably make a bit less, but it will be over a more broad rpm range.

*edit: basically what the dyno I posted in #220 shows is what I'm thinking.

 

While no experience with the 1.8 Miata motor I do have a fair amount with dual GT28's on a 3.6 Porsche motor. I tried 2871's, 2860's and 2868's (Billet Tial compressor). I found with the 2871 the .86 housing hurt spool all else being equal. The 2860 did not has the same problem. It behaved very similar. After talking to Tial they feel the 2871 is a mismatch turbo. The turbine is too small for that size compressor. It is better suited for the GT30 frame.

I found the best results using the 68mm Tial compressor. It uses a extended tip compressor (same as GTX) and spooled faster than either of the other 2 by 200+ RPM's. I did not get to try that one on the .86 housing but I bet the results would be the same as the GT2860.

In a nutshell one of you guys needs to try a GT2860 Tial turbo with a .86 housing.

 

Ha, I wish I had a bunch of snails laying around to experiment with like I used to on subies, but no such luck.

If I get any other turbo it will be an EFR.

Thanks for your input though. Sounds like you're with Sav on specifically the 'tater in that spool/torque delay is minimal going to the larger hotside.

 

Not derail the thread but how well did the 3.6 motors take boost? Where the ones you worked with "stock" internally? head sealing issues? Just curious as I have a 3.6 and I think one day it will need boost too.

 

...but you just posted a chart that directly conflicts with that assertment? The 0.86a/r car is going to make more torque up top, so the only way for a 0.64a/r car to make a "broader" band is for it to make better torque down low. And yet the chart you posted shows Dem's car makes less low-end torque than Hustler's car did - look at the torque numbers at 3000 and 3500rpm. It's not a lot less torque, but it's still less. That's what I was referring to when I said "less torque" earlier.

 

I was talking about post #220.

As for hustler vs dem maps, I agree the spool/lowend looks about the same

 

Is that chart from an SR20, 1.8T, or something else? I've seen charts like that (or maybe/probably that one) before, but never on a Miata motor. The 0.86a/r turbos don't seem to spool dramatically later on the BP. Don't ask me why, but empirically, that's what I've seen. If an A-B test on a BP4W/BP6D did produce a difference, it's certainly not 700+rpm like it is in your example.

 

Sorry just caught this. If you want more info let's take it off line. I have had my hands in lots of 3.6 builds. thogan7242@gmail.com

 

[QUOTE=Savington;495599]84mm 8.7:1 supertech:



glad i just bought my weisco pistons

 

Fail.

 

[QUOTE=drewcook;1118433]Let me know how your wiseco install goes - I installed everything as per manuf. instructions and still have oil burning like the rings didn't seat 1200 miles later.

 

Have fun with your outrageous cold slap. The conditions that caused that failure would break any forged piston on the market. I've gone on to make more power and more torque at higher boost levels on the same pistons.

Don't malign a perfectly good product based on your misunderstanding of why a failure occurred.

 

Are there certain dos and don'ts with forged pistons, namely the Wisecos. I hear a lot about the "piston slap" and such but mine isn't very loud and sounds very quiet at idle once warmed up. I read about how the metal expands differently vs the Supertechs but don't understand what that means in the real world.

 

It is important to ensure the cylinder is clearanced properly for the particular alloy of the piston because they do expand differently. This will mean that some will be looser when cold and need to not be put under a heavy load before warmed up to normal operating temperature. In fact none of them should be put under a heavy load before being brought up to proper operating temperature, but even greater wear can occur in a very loose piston to bore clearance situation.

 

Thanks, but what do you mean by proper operating temperature? Is this monitoring water temp? Or until my oil pressure gauge tells me the oil is warming up? I usually it for oil pressure to start decreasing a little vs what it was at cold start, then I start getting into it more. I don't typically see boost for a few minutes anyway since I'm in a dense neighborhood full of kids. I have to pull out of my garage fairly soon after starting the car since it shakes our house (and neighbors) but then let it sit at idle for a minute or two before gently taking off.

 

Buy a muffler.

Once the water temp reaches the thermostat opens it is considered warmed up. Middle of the water temp gauge...