stock port rew/ efr 8374 low on power?
Full Member
Joined: Nov 2020
Posts: 80
Likes: 15
From: Ohio
Switching out my stock 9 plugs with NGK R7420-10 seemed to have helped my ignition issues. I haven't pushed hard enough to fully say it was the culprit but things seem much better. Car seemed to putter at first and not idle as smooth. Once the plugs warmed up and broke in, the car did better. I'll be looking at getting a proper gap tool so that I can close the gap from the supplied 0.028" to Howard's suggested 0.023". I also want to add a ground wire (4 gauge) from the starter to the battery relocated ground point (rear seatbelt mount). That way, grounding will be less reliant on the chassis.
Full Member
Joined: Nov 2020
Posts: 80
Likes: 15
From: Ohio
Alex, any update on your troubleshooting progress?
With my engine and accessories now grounded directly to battery, I hope puttering is cleared up. If not, it’s more than likely tune related, possibly coil dwell settings in the tune.
With my engine and accessories now grounded directly to battery, I hope puttering is cleared up. If not, it’s more than likely tune related, possibly coil dwell settings in the tune.
unfortunatly no new updates as of now.
i decided to upgrade battery postitve and ground cable to zero gauge (saw voltage drop to 12.7 volts when secondary pumped kicked on! it would slowly climb up but i dont want to risk it)
while doing that im going to change the ground on coils from chassis to battery ground
seems to be running good so far with the 10 plugs, i honestly still dont know if that 350hp dyno showed was correct or now, tuner said to try another dyno jet or try again when its alil cooler (super hot in fl)
i decided to upgrade battery postitve and ground cable to zero gauge (saw voltage drop to 12.7 volts when secondary pumped kicked on! it would slowly climb up but i dont want to risk it)
while doing that im going to change the ground on coils from chassis to battery ground
seems to be running good so far with the 10 plugs, i honestly still dont know if that 350hp dyno showed was correct or now, tuner said to try another dyno jet or try again when its alil cooler (super hot in fl)
Maybe I missed it in the posts, but do you have a direct fuel pump wiring kit? There are a few companies that make kits if you don't have one. Wondering if something is going on with the old wiring and relays if you didn't have a direct wire kit.
https://www.sakebombgarage.com/plug-...ess-fd3s-rx-7/
https://www.sakebombgarage.com/plug-...ess-fd3s-rx-7/
Maybe I missed it in the posts, but do you have a direct fuel pump wiring kit? There are a few companies that make kits if you don't have one. Wondering if something is going on with the old wiring and relays if you didn't have a direct wire kit.
https://www.sakebombgarage.com/plug-...ess-fd3s-rx-7/
https://www.sakebombgarage.com/plug-...ess-fd3s-rx-7/
Full Member
Joined: Nov 2020
Posts: 80
Likes: 15
From: Ohio
Alex - I'm curious to know what wastegate actuator spring load you're using?
Not sure it relates to your issues but I may have figured out my audible knocking(again not convinced its engine related) in the 5000 - 6000rpm range. Convinced it wasn't the engine, the only other possible moving part is the wastegate flap and turbine wheels. Because it only happens shortly after peak boost/torque, I thought maybe the wastegate flap is freaking out and oscillating quickly to control wastegate spring pressure only(14lbs) at that certain point in the map. Anything over 6000rpm the engine starts gobbling up more air and less waste is needed.
I wired open the wastegate flap and went for a drive. Full throttle in 3rd gear to redline, The lowest boost threshold was 13lbs and there was no audible knocking noise. I may have discovered that the wastegate is the culprit and for that reason I'll be lowering my spring to 12 lbs and using the EBC to control boost up to my desired 15lbs. Ideally, 17psi that tapers down to 14 psi at redline.
Not sure it relates to your issues but I may have figured out my audible knocking(again not convinced its engine related) in the 5000 - 6000rpm range. Convinced it wasn't the engine, the only other possible moving part is the wastegate flap and turbine wheels. Because it only happens shortly after peak boost/torque, I thought maybe the wastegate flap is freaking out and oscillating quickly to control wastegate spring pressure only(14lbs) at that certain point in the map. Anything over 6000rpm the engine starts gobbling up more air and less waste is needed.
I wired open the wastegate flap and went for a drive. Full throttle in 3rd gear to redline, The lowest boost threshold was 13lbs and there was no audible knocking noise. I may have discovered that the wastegate is the culprit and for that reason I'll be lowering my spring to 12 lbs and using the EBC to control boost up to my desired 15lbs. Ideally, 17psi that tapers down to 14 psi at redline.
im running the turbosmart iwg dual port with their 14 psi spring. im not sure im actually hearinh knocking though
my knock sensor isnt picking anything up neither.
did notice some bad sputter at times under load whifh i never had (owned fd for about 5 yrs now) after switching to my used 10 plugs, might be time to throw some new ones in
for future ref all my runs and dyno logs posted above were on 9 stock plugs
just recently switched to a set of used 10 range denso plugs i had in my t2 for testing purposes.
my knock sensor isnt picking anything up neither.
did notice some bad sputter at times under load whifh i never had (owned fd for about 5 yrs now) after switching to my used 10 plugs, might be time to throw some new ones in
for future ref all my runs and dyno logs posted above were on 9 stock plugs
just recently switched to a set of used 10 range denso plugs i had in my t2 for testing purposes.
I'm hoping to leave map as is and try on ANOTHER dynojet to see what i get
sadly has been a slow process
I'm also considering changing my meth setup
currently haltech is controlling meth pump thru a ssr with my io box but I'm not getting full flow
may try and change and get a solenoid and have haltech pulse the solenoid instead and just have pump on max all the time
Joined: Oct 2001
Posts: 6,279
Likes: 728
From: Florence, Alabama
if you can hear knocking your motor is toast so you are probably correct as to the wastegate or some other mechanical non motor thingy.
trail plugs run lots hotter than lead. that is why, of course, Mazda selects 9s for the trail and 7s for the lead. mainly to avoid pre-ignition. that's also why the OE plugs do not have a typical thin ground strap. the thin ground strap can become a glow plug and easily cause pre-ignition.
gasoline auto-ignites at 536 F. ethanol and methanol at 878 F.
i wouldn't be surprised to find that your trail plugs are annealed the entire length of the strap and your leads are a bit less. the blackish deposits are carbon which is normal given the richish AFRs we run. since they do not look oily my guess is you are less than 1 oz/gal premix?
the other primary heat factor is timing. what is your timing (lead and trail) at 14 psi? .
trail plugs run lots hotter than lead. that is why, of course, Mazda selects 9s for the trail and 7s for the lead. mainly to avoid pre-ignition. that's also why the OE plugs do not have a typical thin ground strap. the thin ground strap can become a glow plug and easily cause pre-ignition.
gasoline auto-ignites at 536 F. ethanol and methanol at 878 F.
i wouldn't be surprised to find that your trail plugs are annealed the entire length of the strap and your leads are a bit less. the blackish deposits are carbon which is normal given the richish AFRs we run. since they do not look oily my guess is you are less than 1 oz/gal premix?
the other primary heat factor is timing. what is your timing (lead and trail) at 14 psi? .
Last edited by Howard Coleman; Sep 30, 2022 at 05:39 PM.
if you can hear knocking your motor is toast so you are probably correct as to the wastegate or some other mechanical non motor thingy.
trail plugs run lots hotter than lead. that is why, of course, Mazda selects 9s for the trail and 7s for the lead. mainly to avoid pre-ignition. that's also why the OE plugs do not have a typical thin ground strap. the thin ground strap can become a glow plug and easily cause pre-ignition.
gasoline auto-ignites at 536 F. ethanol and methanol at 878 F.
i wouldn't be surprised to find that your trail plugs are annealed the entire length of the strap and your leads are a bit less. the blackish deposits are carbon which is normal given the richish AFRs we run. since they do not look oily my guess is you are less than 1 oz/gal premix?
the other primary heat factor is timing. what is your timing (lead and trail) at 14 psi? .
trail plugs run lots hotter than lead. that is why, of course, Mazda selects 9s for the trail and 7s for the lead. mainly to avoid pre-ignition. that's also why the OE plugs do not have a typical thin ground strap. the thin ground strap can become a glow plug and easily cause pre-ignition.
gasoline auto-ignites at 536 F. ethanol and methanol at 878 F.
i wouldn't be surprised to find that your trail plugs are annealed the entire length of the strap and your leads are a bit less. the blackish deposits are carbon which is normal given the richish AFRs we run. since they do not look oily my guess is you are less than 1 oz/gal premix?
the other primary heat factor is timing. what is your timing (lead and trail) at 14 psi? .
yup running 1/2 Oz per gallon since I still am using stock omp
think timing was setup very soft
think at 5500 rpms 10* leading and maybe 10 or 15 split on just pump fuel map
I'm sure it's more aggressive with water injection map
and that was from what I remember, timing might have been changed since
Full Member
Joined: Nov 2020
Posts: 80
Likes: 15
From: Ohio
Had my car on the dyno (mustang dyno) a few weeks ago and what I've learned is
At 15 psi, street port, 93 pump and safe timing, I was seeing 340whp. This was at 6900 rpm as my laptop was doing some weird things and wouldn't log data above that. Logging continued to get worse with each consecutive pull. I predict 350whp at 7900 rpm.
Torque starts to fall off at 6200 rpms. 0 smoothing looked fine and I'm also direct fire, NGK 7420-10's. My plugs are a little darker, but also premixing almost 2 oz/gallon.
At the end of the day, the dyno should really just be used to make dialing in the AFR and timing much easier and quicker. You must be careful relying on the dyno instruments computed number to verify whether car is doing what it should be doing. Different dyno's read differently, and settings can be tweaked to show varying power numbers. Loaded dynos can also be adjusted. When was the dyno last calibrated....
At 15 psi, street port, 93 pump and safe timing, I was seeing 340whp. This was at 6900 rpm as my laptop was doing some weird things and wouldn't log data above that. Logging continued to get worse with each consecutive pull. I predict 350whp at 7900 rpm.
Torque starts to fall off at 6200 rpms. 0 smoothing looked fine and I'm also direct fire, NGK 7420-10's. My plugs are a little darker, but also premixing almost 2 oz/gallon.
At the end of the day, the dyno should really just be used to make dialing in the AFR and timing much easier and quicker. You must be careful relying on the dyno instruments computed number to verify whether car is doing what it should be doing. Different dyno's read differently, and settings can be tweaked to show varying power numbers. Loaded dynos can also be adjusted. When was the dyno last calibrated....
Had my car on the dyno (mustang dyno) a few weeks ago and what I've learned is
At 15 psi, street port, 93 pump and safe timing, I was seeing 340whp. This was at 6900 rpm as my laptop was doing some weird things and wouldn't log data above that. Logging continued to get worse with each consecutive pull. I predict 350whp at 7900 rpm.
Torque starts to fall off at 6200 rpms. 0 smoothing looked fine and I'm also direct fire, NGK 7420-10's. My plugs are a little darker, but also premixing almost 2 oz/gallon.
At the end of the day, the dyno should really just be used to make dialing in the AFR and timing much easier and quicker. You must be careful relying on the dyno instruments computed number to verify whether car is doing what it should be doing. Different dyno's read differently, and settings can be tweaked to show varying power numbers. Loaded dynos can also be adjusted. When was the dyno last calibrated....
At 15 psi, street port, 93 pump and safe timing, I was seeing 340whp. This was at 6900 rpm as my laptop was doing some weird things and wouldn't log data above that. Logging continued to get worse with each consecutive pull. I predict 350whp at 7900 rpm.
Torque starts to fall off at 6200 rpms. 0 smoothing looked fine and I'm also direct fire, NGK 7420-10's. My plugs are a little darker, but also premixing almost 2 oz/gallon.
At the end of the day, the dyno should really just be used to make dialing in the AFR and timing much easier and quicker. You must be careful relying on the dyno instruments computed number to verify whether car is doing what it should be doing. Different dyno's read differently, and settings can be tweaked to show varying power numbers. Loaded dynos can also be adjusted. When was the dyno last calibrated....
Rotary Freak
Joined: Jan 2002
Posts: 1,643
Likes: 0
From: l.a.
Originally Posted by Howard Coleman
here are your spark plug options:
Denso Iridium
5720 IRE01-31 10 heat range
5721 IRE01-32 10.5
5722 IRE01-34 11
5741 IRE01-35 11.5
NGK Iridium
5501 R 7420 10 heat range
4857 R 7420 10.5
7756 R 7756 11
Denso has a thinner center electrode than NGK. thinner is thought to work better.
lighting a HIGHLY compressed charge is like trying to pound a nail into an extremely hard piece of wood.
a thinner nail is easier to drive.
here's the winner
note what they say on the box...
four tenths of one mm center electrode. (NGK is .5). i am not knocking NGK, just pointing out a difference. the alternative plugs that "fit", BR10ES, feature a 2.45 mm center electrode as do the AR3932 copper plugs.
of course you need to pick the correct heat range. here's how:
notice the ground strap. more than 50% devoid of material. running just a touch too hot. sure, you see residual carbon/oil on other parts of the plug but they are irrelevant. you want half the strap clean.
plugs should be one of the first things you check, just as tires when road racing. your tires will tell you almost everything you need to know as to setup.
Denso Iridium
5720 IRE01-31 10 heat range
5721 IRE01-32 10.5
5722 IRE01-34 11
5741 IRE01-35 11.5
NGK Iridium
5501 R 7420 10 heat range
4857 R 7420 10.5
7756 R 7756 11
Denso has a thinner center electrode than NGK. thinner is thought to work better.
lighting a HIGHLY compressed charge is like trying to pound a nail into an extremely hard piece of wood.
a thinner nail is easier to drive.
here's the winner
note what they say on the box...
four tenths of one mm center electrode. (NGK is .5). i am not knocking NGK, just pointing out a difference. the alternative plugs that "fit", BR10ES, feature a 2.45 mm center electrode as do the AR3932 copper plugs.
of course you need to pick the correct heat range. here's how:
notice the ground strap. more than 50% devoid of material. running just a touch too hot. sure, you see residual carbon/oil on other parts of the plug but they are irrelevant. you want half the strap clean.
plugs should be one of the first things you check, just as tires when road racing. your tires will tell you almost everything you need to know as to setup.
Last edited by AX75F92; Oct 28, 2022 at 11:28 AM.
small update, hopefully heading to dyno in coupes weeks
going to try at a differnt dynojet to see
some minor updates to setup
upgraded to 180amp alternator (0 gauge cables from alternator to fuse box, replaced/upgraded battery grounds, 0 gauge from battery to fuse box)
4 gauge ground from coils straight to battery ground post
added prometh solenoid to pulse meth setup, upgraded meth pump,
changed settings so that haltech now turns pump on and I pulse the solenoid to control flow
added pressure sensor to meth setup to go along with flow sensor
added a thermocouple probe for IAT in stock location in uim
will change plugs to run denso 5720 10 range in leading
and ngk r6601-11in trailing
also changed waterpump to a mazmart remedy (had one already but was leaking) and put new oem thermostat in
going to try at a differnt dynojet to see
some minor updates to setup
upgraded to 180amp alternator (0 gauge cables from alternator to fuse box, replaced/upgraded battery grounds, 0 gauge from battery to fuse box)
4 gauge ground from coils straight to battery ground post
added prometh solenoid to pulse meth setup, upgraded meth pump,
changed settings so that haltech now turns pump on and I pulse the solenoid to control flow
added pressure sensor to meth setup to go along with flow sensor
added a thermocouple probe for IAT in stock location in uim
will change plugs to run denso 5720 10 range in leading
and ngk r6601-11in trailing
also changed waterpump to a mazmart remedy (had one already but was leaking) and put new oem thermostat in
