Irace86.2.0's KPower Turbo K24 Swap

[RedReplicant]

Originally Posted by FrickingReallySlow

How well could the stock motor last at 350whp? I thought @CSGmike said that its life was measured in hours?! Maybe the cost of adding pistons and rods and labor was close to the cost of a replacement K24A2 and its not worth it

He was talking about a 300whp NA K24, not a FI stock motor. With that said, 4Piston will sell you a ~300whp K25 with a warranty or if you lower your target to something like 275whp you can have something that'll probably be more of a few season motor.

With FI, as long as you're not trying to make a bunch of torque down low it should live a pretty decent life at 350whp.

[Ebush]

Originally Posted by FrickingReallySlow

How well could the stock motor last at 350whp? I thought @CSGmike said that its life was measured in hours?! Maybe the cost of adding pistons and rods and labor was close to the cost of a replacement K24A2 and its not worth it

A 350whp turbo k24 with proper tuning would probably last forever in a street car. Mike was referring to max effort NA K24'S, Which would have 400-500whp+ NA.

[Irace86.2.0]

Originally Posted by FrickingReallySlow

How well could the stock motor last at 350whp? I thought @CSGmike said that its life was measured in hours?! Maybe the cost of adding pistons and rods and labor was close to the cost of a replacement K24A2 and its not worth it

Yes, Mike was saying NA under the stipulation that the K24 would be revving to 9k and pushed to the limit on the track. 9k would be a lot. The K20 at 9k is about the same as the K24 at 8,1-8,3k, which seems to be a decently reliable limit, especially for the street.

And the cost of a built FA20 after buying a replacement motor would have been too expensive like $8-10k with a bigger risk than I wanted if the motor blew again.

[FrickingReallySlow]

Would there be a need to use the typeS oil pump since the K24 original one seems to be good to 8K and the WHP is dropping off after 7.5K looking at your dyne plots? maybe just porting the original pump with the balance shafts would be a better option for FI setups? you lose some pressure since you have to feed the balance shafts but some porting work or larger pump gear (6 tooth on type S vs 7 tooth in k24) may get you what you need?

Originally Posted by Irace86.2.0

Yes, Mike was saying NA under the stipulation that the K24 would be revving to 9k and pushed to the limit on the track. 9k would be a lot. The K20 at 9k is about the same as the K24 at 8,1-8,3k, which seems to be a decently reliable limit, especially for the street.

And the cost of a built FA20 after buying a replacement motor would have been too expensive like $8-10k with a bigger risk than I wanted if the motor blew again.

[captain awesome]

Originally Posted by FrickingReallySlow

Would there be a need to use the typeS oil pump since the K24 original one seems to be good to 8K and the WHP is dropping off after 7.5K looking at your dyne plots? maybe just porting the original pump with the balance shafts would be a better option for FI setups? you lose some pressure since you have to feed the balance shafts but some porting work or larger pump gear (6 tooth on type S vs 7 tooth in k24) may get you what you need?

I was thinking on this a bit today as well even for NA application. The question would really be whether the pump assembly fits with the Kpower oil pan and if so does the baffling work as intended?

[Irace86.2.0]

Originally Posted by FrickingReallySlow

Would there be a need to use the typeS oil pump since the K24 original one seems to be good to 8K and the WHP is dropping off after 7.5K looking at your dyne plots? maybe just porting the original pump with the balance shafts would be a better option for FI setups? you lose some pressure since you have to feed the balance shafts but some porting work or larger pump gear (6 tooth on type S vs 7 tooth in k24) may get you what you need?

I had a mild boost leak and fuel limit at redline from not running a return fuel system, maxing out my injectors. Look up other dynos because they can pull well to 9k with gains. The pan would need to be modified, but for sure the baffling would. I don’t know if the stock oil pump has clearance issues with the subframe. It is a nice thought though because 8k is good for now until I build the motor. Ultimately, the shakes aren’t bad enough for me to care.

https://www.s2ki.com/forums/s2000-fo...1180669/page3/

[FrickingReallySlow]

Thanks didn't know that the baffle and custom pan and height could be an issue here. Btw what does the return system buy you? just more even fuel pressure at all RPM instead of being regulated? or just ease of tuning

Originally Posted by Irace86.2.0

I had a mild boost leak and fuel limit at redline from not running a return fuel system, maxing out my injectors. Look up other dynos because they can pull well to 9k with gains. The pan would need to be modified, but for sure the baffling would. I don’t know if the stock oil pump has clearance issues with the subframe. It is a nice thought though because 8k is good for now until I build the motor. Ultimately, the shakes aren’t bad enough for me to care.

[Irace86.2.0]

Originally Posted by FrickingReallySlow

Thanks didn't know that the baffle and custom pan and height could be an issue here. Btw what does the return system buy you? just more even fuel pressure at all RPM instead of being regulated? or just ease of tuning

More constant pressure and temperature, which makes tuning easier and results in more fuel. A returnless system has unused fuel sitting in the fuel rails heating up, as it waits to get burned, which results in a drop in fuel pressure, I believe, and higher fuel temps. The drop in pressure might be from fuel evaporation leading to micro gas pockets. What I do know if that a boost reference FPR is also needed. This increases the fuel pressure proportional to boost, so 60psi with vacuum will raise to 70psi at 10psi of boost. Why is this necessary? Pressure in the rail is 60psi, but pressure in the manifold is 10psi resisting the fuel from squirting out of the injector, so actual fuel pressure at the injector is 50psi, which means the injector is slowly losing potential with the rise in boost, which is exactly the opposite of what you would want. I was seeing fuel pressures in the mid forties after breaking 10psi, which means my injectors at max duty cycle were inadequate despite other with return systems with a reference FPR making far more power.

[RedReplicant]

Worth seeing if you can get a writeup out of ML since he repurposed the unused stock line as a return.

[ML]

Originally Posted by RedReplicant

Worth seeing if you can get a writeup out of ML since he repurposed the unused stock line as a return.

my setup is a hybid I guess with a surge tank in the engine bay. So the fuel goes to the surge tank and then there is a return from the surge to the fuel cell (re using one of the stock fuel lines). then from the surge tank it goes to a boost referenced FPR to the fuel rail which i guess from there is considered "returnless"

[Irace86.2.0]

I will probably run -6AN lines to something like this. I'll have to research it more when I am ready to make the changes to a new tranny.

https://fullblownmotorsports.com/ful...frs-subaru-brz

[ML]

Originally Posted by Irace86.2.0

I will probably run -6AN lines to something like this. I'll have to research it more when I am ready to make the changes to a new tranny.

https://fullblownmotorsports.com/ful...frs-subaru-brz

-6 is what I'm running. that kit seems way overpriced though

[captain awesome]

Just saw that Deatschwerks came out with a dual pump assembly. It's supposedly capable of keeping fuel flow below 1/8th tank plus I think it may flow enough for your application.


https://www.dropbox.com/s/bblxuif0w6...eid=236b735dae


Edit: It's expensive. Like really expensive. Also requires return line.

[ML]

Originally Posted by captain awesome

Just saw that Deatschwerks came out with a dual pump assembly. It's supposedly capable of keeping fuel flow below 1/8th tank plus I think it may flow enough for your application.


https://www.dropbox.com/s/bblxuif0w6...eid=236b735dae


Edit: It's expensive. Like really expensive. Also requires return line.

thats pretty sweet! you can get it without pumps for $430