What kind of rwhp/rwtq could one expect running 12psi of boost from the 2860 with the .64 a/r housing, stock and/or modified 1.8s?

My other issue would be price consideration. My TDR IC would work with the FMII kit, with the compressor reclocked. If I were to look at different manifold options, I'd still need a manifold that puts the compressor outlet just about where the FMII outlet is located. So basically, do the BEGI and FM manifolds put the turbo in the same location? BEGI quotes individual part prices on their site, FM doesn't so I'd have to call them for the prices.

 

I wish I had numbers for my GT2554R for you, but I think it's around 230whp at 15psi. The boost response is amazing, boost onset under 2000rpm and full boost by 3000, mabye a hair more. If you want 300rwhp, it's obviously not going to cut it, but if you're happy with 250whp or so, a little water injection and a GT25R, MABYE a 2860R, is the ticket.

Having said that, if I had $1500 right now and a built motor in the works, I would probably be ordering up a GT2871R right now. If you're going to go bigger than a 2860R, I would get a Bell manifold with a Tial EWG.

 

I haven't checked Garrett's site on the 2871R, but what's the diff between it and the disco potato?

 

It's got the spool of the .64 A/R turbine wheel from the disco potato, but you aren't dealing with the big trim turbines that you get from a 3071. Basically, it flows like a 3071 and spools like a potato.

I think. :gay:

 

But the 2860 with the .64 turbine would still spool faster than the 2871R?

 

Play = High RPM boost.

DD Driving = Quiet no-hp-needed non-boost. You still have engine grunt, just not turbo grunt. Unless you modify your car for low-compression heads or something, its still stock power. Having a tiny turbo is gunna be more noisy driving around town than a big turbo, with all that BOV stuff.

Low end grunt is for beating people from stoplights(or chrismas tree lights?) which I actually didnt see in the OP's First Post.

 

I like that if i drive conservativly and stay under 3K rpm i can get frugall mileage and not worry about sliding around everywhere. And if i want to be agressive and burn the tires off everywhere i just drive trying to stay above 3K

 

I don't do any stoplight action. I am pretty conservative on the street.

 

Decided on a 2871R. Garrett seems to have 3 variants. Yo no comprendo "trim", but I do understand the lower turbine a/r means quicker boost response. I am looking for something that isn't on/off since I open track the car, and with reasonable boost response. I also figure what the heck, shoot for a solid uncorrected 300-350rwhp if I want to, I can always install a 6-speed (I already have the 3.63 gears). The engine can handle a fair amount of boost reliably, and I want good thermal efficiency for track use, willing to trade off some street boost response for no worries with heating things up while on track for 30 minutes. It will be externally wastegated as well. Don't think I'd be running a huge amount of power while on track, though. Gotta tighten the nut behind the wheel first. Thanks again for the help.

 

Wow you realy made up a nice plan there Rick You will enjoy it when all is said and done GL man

 

I did some farting around on the Squirrel Performance site.

Picked the 3 2871R variants and these are the resulting maps:

http://www.squirrelpf.com/turbocalc/...&product_id=33

http://www.squirrelpf.com/turbocalc/...&product_id=34

http://www.squirrelpf.com/turbocalc/...&product_id=35

Which one would suit me? The intial specs were close I think other than what may be the min boost rpm, dunno what's reasonable. Otherwise, the engine should be pretty efficient being fully built, so I made the BSFC .47 instead of the default .43. My rev limiter in the Hydra is set to 7500 right now, really don't want to go higher than that.

I'm running RC 550s with the Hydra btw, so I think they max limit the rwhp to around 300. I could always increase base pressure a bit as the rest of the fuel system is squared away.

 

First fix your VE those numbers are pretty damn low. Then are those the temps you are getting out of you mp62 now? If so they are pretty damn high. At that power level i think .5 or so is about as low as your bsfc is going to get. I think mine at peak was .45 or so and Ben's worked out to be around .47 or so. But both of these where at lower boost level guestimations. From the look of those charts the 1,3 are the best at 16 psi but the 3 is awfull close to the surge line as you get to full boost this could cause a problem with low boost response. Vs # 1 wich ends up smack dab in the middle of the high effeciency island but yeah change up those enviroment numbers abit and see how they look.

 

I didn't mess around with ve, temps, etc, just the 9 gray boxes in the upper left. My MP62 temps are currently lower than what's listed there.

 

After screwing around with the ve and intake temps, it seems that variant 1 is still the better option, the GT2871R, 71mm, 52 trim, .60 A/R. The 48 trim seems to go off to the right of the map a fair amount, and the 56 trim still rides perilously close to the left side of the map.

While on track with the MP62, at 10psi, I saw a max of 41ēC for intake air temps.

 

Those #'s are a good baseline of your IC'ers performance. And will help you to make a better decision. It seems that you already figured that out though.