Turbo sizing inquiry
 

I have an HTA3576 that I was planning on actually getting to install this spring. Unfortunately for me, switching jobs changed my commute from driving 90% interstate to 80% incredibly hilly, backroad highways instead so that changes my general driving style quite considerably.

My question is: Will I get enough response at low load/partial throttle from the turbo to keep my commute tolerable? I need some help from the K04 to keep my RPMs reasonable (2750~3000 RPM) while scaling up these huge hills. I'm driving ~250 miles/week for the commute back and forth and I'm trying to keep my gas mileage fair/keep my revs down.

I know there isn't really any info on the HTA3576, but I'm just trying to get a general idea of what to expect and if I should consider switching to a smaller turbo.

I'd go smaller. When I had a 3071 on my gen1 it was okay in hilly situations but I was always a gear lower than I was with the k04....a 35 will be at least a few hundred rpm worse than that. I'd go witha 28 series or something like a 5858 if you want bigger, it should spool better than a similarly sized garrett.

Not sure about your power goals but sounds like you might want a BNR S3. From what Ive read they are one of the most responsive, and its what I plan on going with since my HP goals are not over 400.

His goals were obviously well over 400 with his turbo choice...which is why I didn't suggest an S3

GTX 2971 or EFR 6758. :smokin:

I had a Garrett GTx3576, and while it made damn good power, it was a complete dog around town... and i didn't even have hills to deal with. I'd suggest smaller, a 3071 should be fine, i remember mine responding pretty well before i swapped to the 35.

Thanks everyone. I was looking towards the 5558 or 5858 as the most likely replacement at this point. I wish I could do an EFR but I don't want to have to sell an organ to do it lol

I'm making the switch from a 35R to a Xona Rotor 6156 (HTZ3076) for specifically of the around the town terribleness....depending on your flange I'd check them out. I had a thread around here somewhere about it.....got a killer deal on it.

Regardless, if you want the high hp and great response, I'd totally recommend anything Forced Performance makes. They have the formula down for that. Otherwise, just hit up a GTX3071 or 2971 and win.

That's why I went with an HTA3576 instead of a GTX3576. More of a fan of FP turbos. I'll probably hit up Xona and see what they say.

http://www.mazdaspeedforums.org/foru...e-tial-195716/

posted about it here.

In my opinion those Precisions are too big. They won't give you jack shit below 3500 RPM's. I think a 3071 is the biggest you could go without losing some response down low. I would just get a GT3071 personally.

Alternatively you cold give the BNR S4 a shot. It's a 3076 which is a little big, but still way smaller than you originally had in mind. The best thing about that turbo is how dirt cheap it is for what you get.

Just been chatting with Xona Rotor/FP about the 5448 (HTZ2871) to the 5756 (HTZ3073) range. The only complication would be getting a TiAL flange for the downpipe AFAIK. The T3 flange would be easier since it comes with a V Band outlet but unfortunately AFI is the only one I know that makes one for us and you can't even get an external wastegate on them because of their design.

Tial is totally worth it man. Le flowz are ridiculous and it looks purty.

The previous owner of my car switched from T3 w/ Steedspeed mani to the cpe mani w/ tial and dramatically decreased the EGT's and brought the spool time down to something a little more reasonable (with this giant 35R) according to the documentation that I have.

But, that being said, I don't think you are going to miss TOO much going either way when you start talking about those smaller framed turbos.

I figured I may as well go with TiAL anyway, if I have the option to go bigger in the future it'd be a better transition. Does the CPE manifold only create issues with stock turbo positioning when using a Precision or is it for all of them?

I don't think it really creates any issue with turbo positioning for any garret style turbos.