|
Sweden made 3rd sprk plug test
Finally after 3 years waiting we hit the RotoTest dyno with our 13B PP dragrace car. Some short specs:) 9:4 cr rotors. RA 2 mm apex seals, 5 pin doweled,Gene Berg 54 mm IDA carb,short 50 mm primaries,Pro Spark sequential ignition and finally the 3rd spark plug FT (Far Trailing) ala Mazda Le Mans 4 rotor engine. The 3rd sparkplug is controlled by a DIS4 and a Megasquirt box at this early prototype stages. First test was to idle at 2k at lambda 1 then switching to 3rd FT plug. Observations were that idle went down to 1.5k stumbling and lambda goes up to 1.25-1.35:icon_tup:Proof that it ignites the lean mixture in the squish. Next test was a static dyno run for 5s at 7.5k, first with 2 plugs and ignition L 20deg T16 deg. Power was 211 hp at hub.Lambda at 0.90. Then connected the FT + wire and tested again... 220 at hub:icon_tup:Lambda went a litttle bit leaner at 0-92-0.94 but was not rejetted due to lack of time. We had big troubles with ignition wires that were to low in resistance, but then switched to 10kohms wires, problem solved:) Spark plugs then:scratch:We use new BUR9EQ in all 3 holes per chamber. The ideal timing for the ignition timing for the FT plug has to be more in depth dyno tested. Finally we did a dynamic 10s run from 5500 to 10 000 rpm. The engine made 295 hp at 9186 rpm according to RotoTest Datmon log ( i lifted the pedal becausse i could hear some small misfires):icon_tdow Now we shall compete in a dragrace event at Kjula Raceway on 30-31/5 Hope to see some 10s time slips from our 800 kg (1765 lbs)Mazda RX-4:rolleyes:
/Lasse |
did you play with split at all?
The only real way to test and see if the far trailing plug is giving a gain would be to tune it with just two till you hit peak then use the far trailing and start all over again. Not trying to shoot down your work just trying to get a feel if you got 9 HP from the extra plug or just the extra split / sparking power. What ignition setup are you running for leading? On my old BP I had a loss of only 3 HP *256 ->253* to the ground removing the trailing when using one CDI box and coil per leading plug and had little change with more or less split. |
First off, cool info. The last two Sevenstock events that I went too, there was a booth and I forgot what the booth name was, but anyway they were selling the third spark plug housings, or they would drill your own housings. I don't see a big gain in horsepower from doing this. I think the main reason why Mazda did it to the 4 rotor was to squeeze some more fuel economy out of the engine for the Le Mons race. But I guess when racing N/A, every little hosepower helps. Looking forward to seeing further tests and results.
|
Originally Posted by nillahcaz
(Post 9215255)
did you play with split at all?
The only real way to test and see if the far trailing plug is giving a gain would be to tune it with just two till you hit peak then use the far trailing and start all over again. Not trying to shoot down your work just trying to get a feel if you got 9 HP from the extra plug or just the extra split / sparking power. What ignition setup are you running for leading? On my old BP I had a loss of only 3 HP *256 ->253* to the ground removing the trailing when using one CDI box and coil per leading plug and had little change with more or less split. /Lasse |
Cool project! Keep us informed.
|
Hey I forgot to ask. How the heck did you get an RX-4 down to 1700lbs?
|
The chassie is still steel stock profile but has been replaced with 1 mm alumina floor. Back halfed with light weight tube front suspension, 25 lbs glas fibre flip front,no innerwalls, engine 3" backward mounted with alumina front fire wall,All glass windows,rear trunk lid glassfibre,carbon fibre 500 grams rear bumper alumina rear wing,Centerline wheels with motorcycle front rims, G-Force tranny, 9" with alumina spool and lightened drums, 2 gallon fuel tank min stainless one JAZ seat with full alumina interior and 10 point roll cage and many more things i can't remember now.Mikael has owned the car since 1987! And built it in 3 steps. W shall weight it on a good car scale this summer, but we have weight it to 1545 lbs on a truck scale (not exact) without Mikael in it last summer. I have pictures but i,m lazy as hell as posting them, but will do! Now i'm heading for a dyno session with a 13B PP rallycross engine today.
/Lasse |
Awesome project!! Its great to see someone trying the third spark plug. No one tries it after they hear it doesn't make huge gains in power.
Since I don't know a whole lot on tuning a rotary (ignition timing), I'll only say be sure you've got the motor tuned for all its worth on two plugs so you know EXACTLY how much you've gained as you tune it with the third. Looking forward to future results! |
Very interesting testing. Would be nice to see what kind of gain is seen all around the rpm range though
|
:) thanks for not taking that the wrong way. I had a unique set up so i don't know how my GDI changed the usefulness of split. I assume your running fixed? it sounds that way, I was running fixed as well at 20 with a spit of 9. but as i said I don't know how the GDI would effect the usefulness of the trailing plugs.
Hope you get some dyno time soon to get some good info out there, I wish you the best of luck with the setup. |
FWIW: The gains from this shouldn't be much. The 26B engine picked up between 1-3% in economy and torque depending on rpm and keep in mind it was all up high. Let's say you have a 300 hp engine. That's between 3 and 9hp gained assuming it all works correctly. It probably won't be a feelable gain. The average street engine would only gain roughly 2-5hp from this. Nothing you'd feel.
Obviously in racing every little bit counts and may be worthwhile on a race engine but I seriously doubt it's anything worth pursuing if people are just going to build street engines. It is cool to see someone playing with it though and the results will be interesting. You can never learn too much. |
Originally Posted by Lasse wankel
(Post 9223626)
The chassie is still steel stock profile but has been replaced with 1 mm alumina floor. Back halfed with light weight tube front suspension, 25 lbs glas fibre flip front,no innerwalls, engine 3" backward mounted with alumina front fire wall,All glass windows,rear trunk lid glassfibre,carbon fibre 500 grams rear bumper alumina rear wing,Centerline wheels with motorcycle front rims, G-Force tranny, 9" with alumina spool and lightened drums, 2 gallon fuel tank min stainless one JAZ seat with full alumina interior and 10 point roll cage and many more things i can't remember now.Mikael has owned the car since 1987! And built it in 3 steps. W shall weight it on a good car scale this summer, but we have weight it to 1545 lbs on a truck scale (not exact) without Mikael in it last summer. I have pictures but i,m lazy as hell as posting them, but will do! Now i'm heading for a dyno session with a 13B PP rallycross engine today.
/Lasse
Originally Posted by rotarygod
(Post 9224483)
FWIW: The gains from this shouldn't be much. The 26B engine picked up between 1-3% in economy and torque depending on rpm and keep in mind it was all up high. Let's say you have a 300 hp engine. That's between 3 and 9hp gained assuming it all works correctly. It probably won't be a feelable gain. The average street engine would only gain roughly 2-5hp from this. Nothing you'd feel.
Obviously in racing every little bit counts and may be worthwhile on a race engine but I seriously doubt it's anything worth pursuing if people are just going to build street engines. It is cool to see someone playing with it though and the results will be interesting. You can never learn too much. See post #3. Repost. LOL |
Originally Posted by nillahcaz
(Post 9224313)
:) thanks for not taking that the wrong way. I had a unique set up so i don't know how my GDI changed the usefulness of split. I assume your running fixed? it sounds that way, I was running fixed as well at 20 with a spit of 9. but as i said I don't know how the GDI would effect the usefulness of the trailing plugs.
Hope you get some dyno time soon to get some good info out there, I wish you the best of luck with the setup. On Monday further testing is to be made with bigger venturies from 47-49mm and re jetting the carb. I use Shell V_Power 99 octane fuel but will be testing E85 also if time permits:) I hope this engine shall make a little bit of 300 hp@9000 rpm or more, but we will see... /Lasse |
Originally Posted by rotarygod
(Post 9224483)
FWIW: The gains from this shouldn't be much. The 26B engine picked up between 1-3% in economy and torque depending on rpm and keep in mind it was all up high. Let's say you have a 300 hp engine. That's between 3 and 9hp gained assuming it all works correctly. It probably won't be a feelable gain. The average street engine would only gain roughly 2-5hp from this. Nothing you'd feel.
Obviously in racing every little bit counts and may be worthwhile on a race engine but I seriously doubt it's anything worth pursuing if people are just going to build street engines. It is cool to see someone playing with it though and the results will be interesting. You can never learn too much. /Lasse |
[QUOTE=ultimatejay;9226005]Sounds awesome. Post some pics when you get a chance please. And what is the best 1/4mile time? Any vids?
Thank's! Best ET 2002 11.42s-120 mph. 60ft 1.62s 1/8 mile 7.21s-96 mph. I have old videos that shall come up on my "new" home page this summer. Hopefully my Webmaster has some time for me...? Looking forward to next weekend when we hit the dragstrip since 2002:icon_tup:Of course hope for 10s time slips:) /Lasse |
GDI -> gas direct injection.
|
|
I think we need more engine bay pictures :)
|
i think we all need more pics period! hot car by the way.
|
|
Very nice metal work on the interior. Lightning holes, good hole pattern, Tranny tunnel cover wher it connects at the firewall is great too. Nice work
|
Has the top dowel pin been eliminated to fit the third spark plug?
|
I was curious about the same thing. DId you just relocate the pin or is there two smaller pins on either side of the plug or something else?
|
Here's a vid of the car, you can see more of the interior and engine bay
http://www.norrortracing.se/fernis/B..._by_Fernis.wmv |
3 years for this?
totally worth it! |
| All times are GMT -5. The time now is 12:45 AM. |
© 2024 MH Sub I, LLC dba Internet Brands