Non-turbo 428rwhp FD build up and history
definitely subscribed to this thread. Stumbled upon this shop looking at 20b subframes. Just love the NA 20b idea ever since I watched the battle at 10,000 rpm hot version videos with the RE-Amemiya car and its PP 20B.
Saw this car for the First Time at Street Life Tour , all i can say is WOW!!!!!!!!! the level of fab and execution was seriously mind blowing. I walked over to the car 3 different times and still couldn't get enuf. Keep up the great work
Ah 500rwhp..... that is the ultiimate goal right? Possibly one day, maybe in another year or so. I would like to break 450 before febuary 
Haha, well over the summer I did build a new intake system. Never updated because it still hasnt made it to the dyno. The sllide throttles need a redesign to have less friction. Roller bearings! But here is the un-finished prototype. Should be a major increase in power
Stumbled onto some vids of the car while I started it up at street life tour. I knew someone had some video of it. Engine was still a bit cold but the crowd needed some noise
http://vimeo.com/29223685
http://vimeo.com/29221959
Have a race in SPO scca in two weeks, so hopefully can make it. Already have two go-pros to borrow for the event. So if all goes well there will be real vids in two weeks!!
Stumbled onto some vids of the car while I started it up at street life tour. I knew someone had some video of it. Engine was still a bit cold but the crowd needed some noise
http://vimeo.com/29223685
http://vimeo.com/29221959
Have a race in SPO scca in two weeks, so hopefully can make it. Already have two go-pros to borrow for the event. So if all goes well there will be real vids in two weeks!!
Nice pic too!
Wow, is all i can say about this build and thread. didn't think i would learn something new this morning about displacement. I'm looking forward to seeing some serious track videos of this car in the near future. Craftsmanship like this really inspires me to be an mechanical engineer more and more.
Joined: May 2005
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From: North Bay, Ontario
Hey Logan, it looks from the pictures that the new intake (the sideport portion of it anyways) is a bit longer than the shortened 20B manifold, are you looking to shift the powerband, or ???
Wow, is all i can say about this build and thread. didn't think i would learn something new this morning about displacement. I'm looking forward to seeing some serious track videos of this car in the near future. Craftsmanship like this really inspires me to be an mechanical engineer more and more.
For sure, would love to have some on-track lessons with a experienced Rx7 driver to learn more on driving it properly. You competed in the grassroots magazine "ultimate track car challenge" right? Won the fastest mazda too?
I did. I was happy with how it turned out for only having 330rwhp(TTS trim), but when Fritz's transmission lost 3rd gear... my competition was greatly reduced. I'm hoping to get to do it again in 2012, and thinking about bringing the car up to maybe the 450rwhp range for the event. You should look into doing it next year. VIR is an awesome track and it's a really fun weekend in general. We could do the UTCC Friday, and then race and/or TT on Saturday and Sunday.
Can't wait to see the SPO video. How many guys do you normally have in SPO in your region?
Can't wait to see the SPO video. How many guys do you normally have in SPO in your region?
I did. I was happy with how it turned out for only having 330rwhp(TTS trim), but when Fritz's transmission lost 3rd gear... my competition was greatly reduced. I'm hoping to get to do it again in 2012, and thinking about bringing the car up to maybe the 450rwhp range for the event. You should look into doing it next year. VIR is an awesome track and it's a really fun weekend in general. We could do the UTCC Friday, and then race and/or TT on Saturday and Sunday.
Can't wait to see the SPO video. How many guys do you normally have in SPO in your region?
Can't wait to see the SPO video. How many guys do you normally have in SPO in your region?
It did extremely well for 330hp setting! I would love to enter next year, hopefully that driving skills package gets off backorder and sent over to me by then lol. Either way it would be a great time though. I have heard SPO is not really a popular entry, so I might be one of the few running it. Guess wait and see who shows up that day.
Thank you, will be posting lots of new stuff here in the next couple days
I didnt intend for the update to take so long... but I think one more "increase" can happen this monday. Been waaaaaaaaay too busy with customer cars and v-mount production and had to toss development aside for a few weeks.
For me personally, cheaper than normal. I bought the engine back in 04' with one blown rotor at $2500. New rotor housings, ceramics, balancing, clearancing, drysump were all added in 06'. Havent touched the internal engine since then. So it was a "buy once cry once type" of thing
If I can figure out where my microsoft paint went, I would post some progress dyno charts. If not, tuesday next week will be the whole chapter of updates all at once.
For me personally, cheaper than normal. I bought the engine back in 04' with one blown rotor at $2500. New rotor housings, ceramics, balancing, clearancing, drysump were all added in 06'. Havent touched the internal engine since then. So it was a "buy once cry once type" of thing
If I can figure out where my microsoft paint went, I would post some progress dyno charts. If not, tuesday next week will be the whole chapter of updates all at once.
Chapter 1- recovery of lost horsepower
Alright I figured out how to save the dyno charts on this computer. So, as some of you may recall, I installed a new 3.5" exhaust this spring, and it lost some hp. Alot of hp. I was concerned that it was the diameter that killed it. BUT turns out the exhaust gaskets I used on the header (which were aftermarket, and softer) blew out the first time the engine fired up. The header leak was so bad it dropped 32 horsepower. This shows how important the proper velocity is in a n/a engine like this!
So I removed the header, put back on the stock turbo style gaskets which fixed all the leaks. Result? 432 This was without the race plugs, which add 2hp. So that is 434, right back to where I started. YES!! now I could continue to test new setups.
Chapter 2- finally real intake testing
So this marks the point where I started to get more serious in my attempt at very high n/a horsepower. Up till now, I was using stock based intake systems and quickly made p-port manifolds. No ITB's, or even real air horns. That had to change.
Even though the new prototype teflon slide throttle setup had too much friction during running, I just did a hillbilly modification and added a **** ton of return springs. The throttle felt like a clutch pedal but I didnt care. Just needed it for dyno testing The actual slide throttles are being machined and are fully ball bearing supported.
Here is the pic of the new intake, which is full ITB, slide throttle, velocity stacks and external bell mouth injection. Bosch 550cc injectors for more atomization (same as ID 550cc)
This new intake was fully adjustable in length. So I started at a very long length, and worked my way down 2" at a time. The longest length still showed HUGE promise. The increase in torque was exciting, over 30ft-lbs at 6800, and 8ft-lbs higher than previous peak.
Each time the intake was adjusted, of course the torque shifted upwards. As the torque grew, the injectors maxed out. I turned up the fuel pressure, did all types of things. Couldnt get the afr over 8500 to be in range. High 14's to 10k. This hurt top end hp, would have been 438-440rwhp if I had more fuel. Peak torque however was now at 267 which is a 17ft-lb gain over the previous best!
Power under the curve was more than substantial. The was the end of dyno day #1. No way could I stop just there.
Chapter 3- quest for more.
The days to come, I started to think a bit harder. Reviewing and crunching my old calculations vs. the new data. Then, Carlos Lopez happened to give me a call. During our usual conversation about all things rotary, he brought up something. That man will forget more than most will ever know. Totally by coincidence he made me realize a error I had been making for quite some time.
So I busted my *** and did all the revisions I had pondered about. And went back to the dyno where the really impressive stuff happened.
Chapter 4- where all the fun began
I will post all that very soon
Alright I figured out how to save the dyno charts on this computer. So, as some of you may recall, I installed a new 3.5" exhaust this spring, and it lost some hp. Alot of hp. I was concerned that it was the diameter that killed it. BUT turns out the exhaust gaskets I used on the header (which were aftermarket, and softer) blew out the first time the engine fired up. The header leak was so bad it dropped 32 horsepower. This shows how important the proper velocity is in a n/a engine like this!
So I removed the header, put back on the stock turbo style gaskets which fixed all the leaks. Result? 432
This was without the race plugs, which add 2hp. So that is 434, right back to where I started. YES!! now I could continue to test new setups. Chapter 2- finally real intake testing
So this marks the point where I started to get more serious in my attempt at very high n/a horsepower. Up till now, I was using stock based intake systems and quickly made p-port manifolds. No ITB's, or even real air horns. That had to change.
Even though the new prototype teflon slide throttle setup had too much friction during running, I just did a hillbilly modification and added a **** ton of return springs. The throttle felt like a clutch pedal but I didnt care. Just needed it for dyno testing
The actual slide throttles are being machined and are fully ball bearing supported.Here is the pic of the new intake, which is full ITB, slide throttle, velocity stacks and external bell mouth injection. Bosch 550cc injectors for more atomization (same as ID 550cc)
This new intake was fully adjustable in length. So I started at a very long length, and worked my way down 2" at a time. The longest length still showed HUGE promise. The increase in torque was exciting, over 30ft-lbs at 6800, and 8ft-lbs higher than previous peak.
Each time the intake was adjusted, of course the torque shifted upwards. As the torque grew, the injectors maxed out. I turned up the fuel pressure, did all types of things. Couldnt get the afr over 8500 to be in range. High 14's to 10k. This hurt top end hp, would have been 438-440rwhp if I had more fuel. Peak torque however was now at 267 which is a 17ft-lb gain over the previous best!
Power under the curve was more than substantial. The was the end of dyno day #1. No way could I stop just there.
Chapter 3- quest for more.
The days to come, I started to think a bit harder. Reviewing and crunching my old calculations vs. the new data. Then, Carlos Lopez happened to give me a call. During our usual conversation about all things rotary, he brought up something. That man will forget more than most will ever know. Totally by coincidence he made me realize a error I had been making for quite some time.
So I busted my *** and did all the revisions I had pondered about. And went back to the dyno where the really impressive stuff happened.
Chapter 4- where all the fun began
I will post all that very soon
Last edited by GtoRx7.; Nov 25, 2011 at 03:06 AM.
