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I purposely did not want to show too much. Still tweaking some things with flow paths and runner geometries and such.
Design brief: for use in a primarily street car. So, response and reliability over max power. Packaging which minimizes relocation of components; I'm designing it around the Hasport engine mount. It will keep the stock black heat shield which protects the A/C line, battery, electrical box. The only thing that needs to be relocated is the oil filter to clear space for the compressor intake tube.
So why not the PTuning? It doesn't quite meet my packaging requirements and it has boost control/creep issues. Why not the SOS TSMax? It doesn't have a good top-end because I feel their manifold design is too restrictive. And I'll be using the G25-660, 0.72 A/R. So.... that's all I want to say at this point
Totally understand. I've been patiently waiting to see your turbo setup and I'm in no rush. I have the same "problem" with the existing kits on the market. One can't hold low boost and creeps (w/o a restrictor plate), and SOS is just limiting. While the SOS kit would meet my needs, I'd like a little more headroom. I'd be very happy w/ ~350whp for the track. Interesting you're going to go with a "built" motor. Have you found a way w/o having to sleeve the block? It seems to be hit or miss in my experience with sleeved blocks and problems with them down the road (sleeves sinking, shifting, sinking, etc).
I know you mentioned previously you're not going to go with a FMIC, have you changed your mind? It seems like just buying the SOS v mount setup is an "affordable" way to do a v mount setup and keep the a/c. That's certainly what I'd be inclined to run.
What fuel and power level are you aiming for? Is it a bolt on or complete engine build? What fuel are you planing to use?
You may find Borg Warner's Matchbot useful: Performance Turbos | BorgWarner Turbo Systems
Just an FYI David. Khiem has quite a bit of professional experience with turbos and knows his stuff (as in that's his day job). You can be sure that everything will be WELL thought out.
Are you planning on turbo cams or re-timing OEM to turbo settings? Are you planning on thermal coatings (valves faces, combustion chamber, piston crown, exhaust port) to lower surface temps?
What engine speed do you anticipate? I was finding when trying to spec a configuration for that power level from 3L it was hard to find a turbo to produce the flow with a low pressure ratio (12-14psig MAP). It looks like you plan a slightly higher pressure ratio. Have you mapped it to compressor maps and looked at the turbine expansion ratio? BW has both in Matchbot. It sobering when looking for high HP at low boost levels.
Sidebar: if replacing pistons are you considering abradable coatings for the skirt or gapless top ring to reduce blowby? Is 125hp/cylinder within the range of the OEM rods or does that risk bending rods from excessive ignition advance at lower engine speeds?
No coatings or reducing valve overlap or cams or head work. As 99% of people will not be going into the engine, I do not want to either so as to have more representative performance. The vast majority of people just bolt on a turbo kit and go. Plus, I'm not made of money; it's a miracle my wife is letting me spend as much as I am, ha! AP2 engine, so I had my redline bumped to 8500rpm with the KPro, though I typically shifted at 8000rpm. It's just nice to have the overrev capacity there if needed like on 600cc sport bikes. I was told 8200rpm will still have decent engine life, but 8500rpm will cause significantly increased piston ring wear. The only 'extra' thing I'm doing is WPC on the crank, cams, and wrist pins to reduce friction in the big friction parts of the engine.
Totally understand. I've been patiently waiting to see your turbo setup and I'm in no rush. I have the same "problem" with the existing kits on the market. One can't hold low boost and creeps (w/o a restrictor plate), and SOS is just limiting. While the SOS kit would meet my needs, I'd like a little more headroom. I'd be very happy w/ ~350whp for the track. Interesting you're going to go with a "built" motor. Have you found a way w/o having to sleeve the block? It seems to be hit or miss in my experience with sleeved blocks and problems with them down the road (sleeves sinking, shifting, sinking, etc).
I know you mentioned previously you're not going to go with a FMIC, have you changed your mind? It seems like just buying the SOS v mount setup is an "affordable" way to do a v mount setup and keep the a/c. That's certainly what I'd be inclined to run.
Just pistons to drop the CR to allow for good power on 91 octane along with a relatively high back-pressure exhaust system. Going with the Mahle pistons which are stated to be FRM compatible, so just drop-in and beefier rods while I'm in there.If using E85, could just stick with the stock bottom-end if limiting to 500whp. Current plan is to go with an air-to-water setup, but it is much more complicated than a simple air-to-air. Packaging the IC will be interesting.... benefit being shorter IC plumbing for better response and the heat exchanger to cool the water will have fans on it. So even while stationary on the street, the water for the IC will stay at ambient. So always 'cold' for the IC even when leaving from a stop. Again, the 'street' car bias instead of track car. Track car, easy decision, air-to-air. Air-to-air is much more simple, lighter, and cheaper. Which makes me have second thoughts about the air to water....
The G25-660 is consistently showing 550whp on E85 which is what I expect for a 60lbs/min turbo which is close to my rule of thumb of 9whp per 1lb/min flow. I figure on crap 91 oct Cali pump gas, I can do 420whp (rule of thumb, 7whp per 1lb/min) which is right at 500hp crank.
Actually left the other job 2.5 years ago. And.... I have to go into the office in about 30 min and knock out some work for a few hours today. sigh.
Have you mapped it to compressor maps and looked at the turbine expansion ratio? BW has both in Matchbot. It sobering when looking for high HP at low boost levels.
Oh yeah, I did an initial match targeting a bit more torque (360tq) and hp (550hp) at the crank with a GTX3071R. Backing those numbers down a bit to end up with 500hp will result in a higher efficiency point on the G25-660 compressor map. And the turbine is quite a bit more efficient, though I don't know by how much. I haven't bothered checking what the new numbers will be with the G25.
Just pistons to drop the CR to allow for good power on 91 octane along with a relatively high back-pressure exhaust system. Going with the Mahle pistons which are stated to be FRM compatible, so just drop-in and beefier rods while I'm in there.If using E85, could just stick with the stock bottom-end if limiting to 500whp. Current plan is to go with an air-to-water setup, but it is much more complicated than a simple air-to-air. Packaging the IC will be interesting.... benefit being shorter IC plumbing for better response and the heat exchanger to cool the water will have fans on it. So even while stationary on the street, the water for the IC will stay at ambient. So always 'cold' for the IC even when leaving from a stop. Again, the 'street' car bias instead of track car. Track car, easy decision, air-to-air. Air-to-air is much more simple, lighter, and cheaper. Which makes me have second thoughts about the air to water....
The G25-660 is consistently showing 550whp on E85 which is what I expect for a 60lbs/min turbo which is close to my rule of thumb of 9whp per 1lb/min flow. I figure on crap 91 oct Cali pump gas, I can do 420whp (rule of thumb, 7whp per 1lb/min) which is right at 500hp crank.
Actually left the other job 2.5 years ago. And.... I have to go into the office in about 30 min and knock out some work for a few hours today. sigh.
Really? I'm only expecting mid 4's out of mine. Your setup sounds similar to mine. I'm also doing air to water. My thought is for 2 or 3 laps that I'm going for I can cool the water to have a much lower temp then ambient.
Really? I'm only expecting mid 4's out of mine. Your setup sounds similar to mine. I'm also doing air to water. My thought is for 2 or 3 laps that I'm going for I can cool the water to have a much lower temp then ambient.
You're running a K24 right? The G25-660 will do 550whp if you push it though you'll be operating at a lower pressure ratio. I'm assuming no cat because track car? That should free up a good chunk of power. What fuel? If you're doing SCCA TT and only 2-3 laps..... maybe do a half radiator, and run air-to-air and air-to-water ICs. Air-air gets you down near ambient, air-water sub-cools with the ice in the reservoir.
You're running a K24 right? The G25-660 will do 550whp if you push it though you'll be operating at a lower pressure ratio. I'm assuming no cat because track car? That should free up a good chunk of power. What fuel? If you're doing SCCA TT and only 2-3 laps..... maybe do a half radiator, and run air-to-air and air-to-water ICs. Air-air gets you down near ambient, air-water sub-cools with the ice in the reservoir.
I'm in Florida. these things cook with turbos on the outlap. My main reason for air to water was to have the intercooler not in front of the radiator. The intercooler is split in 2 and put inside the bumpers with a tank in the passenger foot well or trunk (haven't mounted it yet). Plan is to run the tank full of ice. I'm yet to see a over 500whp G25 660 dyno. But I saw a K20 made 480whp with one and still had 20k in turbo rpm left. I don't intend to push it to hard. 450whp will be enough to break other things on the car so I'll start there.
I'm in Florida. these things cook with turbos on the outlap. My main reason for air to water was to have the intercooler not in front of the radiator. The intercooler is split in 2 and put inside the bumpers with a tank in the passenger foot well or trunk (haven't mounted it yet). Plan is to run the tank full of ice. I'm yet to see a over 500whp G25 660 dyno. But I saw a K20 made 480whp with one and still had 20k in turbo rpm left. I don't intend to push it to hard. 450whp will be enough to break other things on the car so I'll start there.
RS Motors and their One Lap of America Evo. Check out their Facebook page. The red line is the 660, the brown line is the 550, both in 0.72 A/R. On my buddy's Pikes Peak car, 480-490whp with another 30k of turbo speed left. Doing some rough math, it's good for around 550-560whp maxed out.
RS Motors and their One Lap of America Evo. Check out their Facebook page. The red line is the 660, the brown line is the 550, both in 0.72 A/R. On my buddy's Pikes Peak car, 480-490whp with another 30k of turbo speed left. Doing some rough math, it's good for around 550-560whp maxed out.
07-29-2018, 05:42 AM
