Swapping S5 TII n370 AFM for Cosmo 13b-re n390
06-02-10, 01:10 PM
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Swapping S5 TII n370 AFM for Cosmo 13b-re n390
I thought I'd make a thread letting you guys know how it works out for me.
I have a 87 TII chassis with S5 TII engine and electronics,S5 hybrid turbo with a Knightsport chipped ecu and AFC neo for fine tuning, I dyno 361whp 309ft-lbs, here's a link to my dyno thread to save having to get into that to much.
https://www.rx7club.com/time-slips-dyno-128/new-dyno-numbers-361-5whp-309ft-lbs-892199/
Anyways last week my n370 AFM finally gave out after the 3 years of abuse i'd gave it and who knows what before. I found probably the only guy in my area that had one that he ran on his S5 TII FB before he went megasquirt. it ended up being a N390, I went home and tried it out, it worked good.
after it was on and the ecu recalibrated itself i had to add more fuel to idle before i was takin away 26% due to my walbro and that ecu, and that would give me a nice steady 13:1 idle. i ended up having to back it off to 17%
the low loads just needed minor tweaking to get it all back to where i had it
I richened up my high maps from 4000 up to be safe i did couple quick pulls to redline in 2nd just to try it, it was around 10.5:1 so it doesnt have any problems up top I deliberately left it rich just to test it. it started raining so i couldn't start any actual tuning
anyways so far so good i'll post more info when i can go retune it.
as for the n390 afm its a bit different style than the n370 looks to be less restrictive when the cone is fully open when i check the resistance and compare it to the S5 FSM its all withing specs i figure it must have a bit firmer spring that would work out better for my higher boost...... and i can actually shove a 3" filter on the end of it. I'll post pictures of it tomorrow most likely.
i read before there's people in japan that use the JE50 VAF from the JDM 200hp klze , someone on this thread tried using one from 929 or something but that would have been a crappy kl01 from the USDM 160hp klde , they cant even handle the klze let alone a turbo rotary, anyways i also have to of those sitting in my storage room, i was gonna try one but i found the other AFM maybe i'll try it out once see how it works too
I have a 87 TII chassis with S5 TII engine and electronics,S5 hybrid turbo with a Knightsport chipped ecu and AFC neo for fine tuning, I dyno 361whp 309ft-lbs, here's a link to my dyno thread to save having to get into that to much.
https://www.rx7club.com/time-slips-dyno-128/new-dyno-numbers-361-5whp-309ft-lbs-892199/
Anyways last week my n370 AFM finally gave out after the 3 years of abuse i'd gave it and who knows what before. I found probably the only guy in my area that had one that he ran on his S5 TII FB before he went megasquirt. it ended up being a N390, I went home and tried it out, it worked good.
after it was on and the ecu recalibrated itself i had to add more fuel to idle before i was takin away 26% due to my walbro and that ecu, and that would give me a nice steady 13:1 idle. i ended up having to back it off to 17%
the low loads just needed minor tweaking to get it all back to where i had it
I richened up my high maps from 4000 up to be safe i did couple quick pulls to redline in 2nd just to try it, it was around 10.5:1 so it doesnt have any problems up top I deliberately left it rich just to test it. it started raining so i couldn't start any actual tuning
anyways so far so good i'll post more info when i can go retune it.
as for the n390 afm its a bit different style than the n370 looks to be less restrictive when the cone is fully open when i check the resistance and compare it to the S5 FSM its all withing specs i figure it must have a bit firmer spring that would work out better for my higher boost...... and i can actually shove a 3" filter on the end of it. I'll post pictures of it tomorrow most likely.
i read before there's people in japan that use the JE50 VAF from the JDM 200hp klze , someone on this thread tried using one from 929 or something but that would have been a crappy kl01 from the USDM 160hp klde , they cant even handle the klze let alone a turbo rotary, anyways i also have to of those sitting in my storage room, i was gonna try one but i found the other AFM maybe i'll try it out once see how it works too
06-02-10, 09:15 PM
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i forget, but i think out of all of the sliding cone style afms the S5 might be the smallest. all of the USDM V6 afms are the 3" inlet.
a friend of mine has one on an NA FC, they said it helped a little, but they did do a bunch of extra work at the same time
N390 is the 13B cosmo engine btw
a friend of mine has one on an NA FC, they said it helped a little, but they did do a bunch of extra work at the same time
N390 is the 13B cosmo engine btw
06-04-10, 04:28 AM
#3
Exhaust Manifold Leak
I'm running 20B maf, works fine, running slightly rich at idle (steady 600rpm) around 11.5:1, but it seems to be a tad lean between 7-8k, there it goes to 13.5:1 at 0.6-0.5bar, it has knightsports hybrid turbo, racing beat exh, RE Amemiya type C ecu running 98 oct, stock engine
somehow it feels very flat in midrange even it's running nice 11.5:1's at .8bar, top end boost falls off to .6 bar, so I guess the exh manifold is cracked or turbine housing, it used to creep up high before I ported the wastegate
FC3Sdrift, what boost are you running for that 360whp?
somehow it feels very flat in midrange even it's running nice 11.5:1's at .8bar, top end boost falls off to .6 bar, so I guess the exh manifold is cracked or turbine housing, it used to creep up high before I ported the wastegate
FC3Sdrift, what boost are you running for that 360whp?
06-08-10, 11:10 AM
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06-08-10, 01:49 PM
#7
I think i'm going to go with a N390 AFM since i most likely will not be able to find a 20b one very quickly.
I was about to buy a klze JE50 AFM, since they are pretty easy to come by. But after a lot of searching, it seems that it has been done, and its not all that great. At least the N390 RE one was intended for a turbo rotary...
Than ks for posting your findings. Would like to see your dyno comparisons whenever you get it fully tuned again.
I was about to buy a klze JE50 AFM, since they are pretty easy to come by. But after a lot of searching, it seems that it has been done, and its not all that great. At least the N390 RE one was intended for a turbo rotary...
Than ks for posting your findings. Would like to see your dyno comparisons whenever you get it fully tuned again.
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06-18-10, 10:10 PM
#10
I've got an NF01 I used for my turbo swap...I can't speak about S4 swaps or even N370 but the filter side of the MAF is larger on the outside diameter of the MAF than the N350. I'm using an Apexi cone filter and I had to grind down the outside edge of NF01 so that it would fit in the Apexi.
I'm not sure about inner dimension of the filter side, but the outer is larger. I had to swap the rubber gasket from the N350 to the NF01.
Are you sure NF01 is a 20B MAF tho? I thought this whole time it was a Cosmo MAF but for a 13B. I"ll have to do some research I guess.
I'm not sure about inner dimension of the filter side, but the outer is larger. I had to swap the rubber gasket from the N350 to the NF01.
Are you sure NF01 is a 20B MAF tho? I thought this whole time it was a Cosmo MAF but for a 13B. I"ll have to do some research I guess.
06-17-11, 09:06 PM
#11
Time for an update:
I'm currently running this afm on an s4 t2. I wired the s5 connector in parallel to the s4 so I can switch back and forth (I am not sure if that affects the signal).
I did a test run and the same map that had me @ 9-10 afr w/ the n318 (s4 t2) ran 11-12 afr w/the n390. Cruise was 14 afr, and acceleration was fine. The only problem seems to bee idle.....it doesn't. I have added 10% fuel in vac below 1k rpm, and it seems to be getting better, but even w/ the bac it won't hold idle, yet....
I'm currently running this afm on an s4 t2. I wired the s5 connector in parallel to the s4 so I can switch back and forth (I am not sure if that affects the signal).
I did a test run and the same map that had me @ 9-10 afr w/ the n318 (s4 t2) ran 11-12 afr w/the n390. Cruise was 14 afr, and acceleration was fine. The only problem seems to bee idle.....it doesn't. I have added 10% fuel in vac below 1k rpm, and it seems to be getting better, but even w/ the bac it won't hold idle, yet....
06-18-11, 03:46 PM
#12
Nothing to see here.
Time for an update:
I'm currently running this afm on an s4 t2. I wired the s5 connector in parallel to the s4 so I can switch back and forth (I am not sure if that affects the signal).
I did a test run and the same map that had me @ 9-10 afr w/ the n318 (s4 t2) ran 11-12 afr w/the n390. Cruise was 14 afr, and acceleration was fine. The only problem seems to bee idle.....it doesn't. I have added 10% fuel in vac below 1k rpm, and it seems to be getting better, but even w/ the bac it won't hold idle, yet....
I'm currently running this afm on an s4 t2. I wired the s5 connector in parallel to the s4 so I can switch back and forth (I am not sure if that affects the signal).
I did a test run and the same map that had me @ 9-10 afr w/ the n318 (s4 t2) ran 11-12 afr w/the n390. Cruise was 14 afr, and acceleration was fine. The only problem seems to bee idle.....it doesn't. I have added 10% fuel in vac below 1k rpm, and it seems to be getting better, but even w/ the bac it won't hold idle, yet....
06-20-11, 11:22 AM
#13
By mastery of magic and by way of the 2010-2011 time vortex!!!
...Unfortunately the rtek does not allow for manipulation of the idle fuel map (which is separate from the regular fuel map). This is a problem because the air bypass on the n390 is significantly greater than the n318.
For example for the same quantity of air "100" it would SEEM that:
N318 bypasses 20 and reads 80
N390 bypasses 40 and reads 60
Thus, the stock idle map does not inject enough fuel. The difference can easily be accounted for with tuning @ higher rpm and in fact is the key benefit of this mod however all is for naught if it can't be made to idle.
During warmup (1100-1200 rpm/ 12-13afr)
n318 shows a reading of 1.0 lbs/min
n390 shows a reading of 0.7 lbs/min
In theory, since measured airflow is -30% then if fuel @ idle could be increased by 30% then it should idle...
...Unfortunately the rtek does not allow for manipulation of the idle fuel map (which is separate from the regular fuel map). This is a problem because the air bypass on the n390 is significantly greater than the n318.
For example for the same quantity of air "100" it would SEEM that:
N318 bypasses 20 and reads 80
N390 bypasses 40 and reads 60
Thus, the stock idle map does not inject enough fuel. The difference can easily be accounted for with tuning @ higher rpm and in fact is the key benefit of this mod however all is for naught if it can't be made to idle.
During warmup (1100-1200 rpm/ 12-13afr)
n318 shows a reading of 1.0 lbs/min
n390 shows a reading of 0.7 lbs/min
In theory, since measured airflow is -30% then if fuel @ idle could be increased by 30% then it should idle...
06-20-11, 12:55 PM
#14
Nothing to see here.
By mastery of magic and by way of the 2010-2011 time vortex!!!
...Unfortunately the rtek does not allow for manipulation of the idle fuel map (which is separate from the regular fuel map). This is a problem because the air bypass on the n390 is significantly greater than the n318.
For example for the same quantity of air "100" it would SEEM that:
N318 bypasses 20 and reads 80
N390 bypasses 40 and reads 60
Thus, the stock idle map does not inject enough fuel. The difference can easily be accounted for with tuning @ higher rpm and in fact is the key benefit of this mod however all is for naught if it can't be made to idle.
During warmup (1100-1200 rpm/ 12-13afr)
n318 shows a reading of 1.0 lbs/min
n390 shows a reading of 0.7 lbs/min
In theory, since measured airflow is -30% then if fuel @ idle could be increased by 30% then it should idle...
...Unfortunately the rtek does not allow for manipulation of the idle fuel map (which is separate from the regular fuel map). This is a problem because the air bypass on the n390 is significantly greater than the n318.
For example for the same quantity of air "100" it would SEEM that:
N318 bypasses 20 and reads 80
N390 bypasses 40 and reads 60
Thus, the stock idle map does not inject enough fuel. The difference can easily be accounted for with tuning @ higher rpm and in fact is the key benefit of this mod however all is for naught if it can't be made to idle.
During warmup (1100-1200 rpm/ 12-13afr)
n318 shows a reading of 1.0 lbs/min
n390 shows a reading of 0.7 lbs/min
In theory, since measured airflow is -30% then if fuel @ idle could be increased by 30% then it should idle...
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