Rob Dahm's overhyped underperforming turbo 4 rotor RX-7 build
06-22-16, 05:05 PM
#28
How many pounds of pressure are you running on that car? How many are you willing to run? Hell my 3 rotor is a fast rotary powered street car. I'm not going to spend 150k on a build to make a car slightly faster than it haha
I'm not going to make statements like that without being able to measure and quantify. It will break the fastest 1/2 mile record for rotary engine street cars. I dont mind getting beat after. i just want to say i did something notable. Obviously a drag car could line up the half mile and coast almost the whole way to a record, but thats not what my intentions are for this beast.
In a less quantifiable sense, i want to take the car to TX2K and make an impression out there. Knock out a couple TT Gallardos. That would make it so enjoyable
I'm not going to make statements like that without being able to measure and quantify. It will break the fastest 1/2 mile record for rotary engine street cars. I dont mind getting beat after. i just want to say i did something notable. Obviously a drag car could line up the half mile and coast almost the whole way to a record, but thats not what my intentions are for this beast.
In a less quantifiable sense, i want to take the car to TX2K and make an impression out there. Knock out a couple TT Gallardos. That would make it so enjoyable
06-22-16, 10:00 PM
#29
It would be a dream to have someone represent rotaries properly at the texas mile. I think you would need about 3000whp to make a huge impression with e85 or methanol with our FR platform. If you decide to make it, I'm sure you'll have tons of rotary love and support. I personally would take a week off to see you make this run.
06-23-16, 12:44 AM
#31
The Texas Mile really is a hell of an event. Like ZoomZoom said, the cars suffer from lack of grip at speed, but the majority of them are pushing over 2k WHP! I would love to see a strong showing and there presently is not a rotary powered vehicle record, so Rob's record could be the first to make headway in this realm.
Just as examples, I pulled two articles on some Texas Mile cars that are seriously fast.
This GTR
2000+HP R35 GT-R Specs - Texas Godzilla
This GT40
M2K Motorsports 280 mph Ford GT
Based on Rob's turbo choice and the airflow potential of a 4 rotor, it should make at least 1200 WHP at around 29 psi, which is astounding to say the least.
Here is the compressor map:
Just as examples, I pulled two articles on some Texas Mile cars that are seriously fast.
This GTR
2000+HP R35 GT-R Specs - Texas Godzilla
This GT40
M2K Motorsports 280 mph Ford GT
Based on Rob's turbo choice and the airflow potential of a 4 rotor, it should make at least 1200 WHP at around 29 psi, which is astounding to say the least.
Here is the compressor map:
Last edited by ACR_RX-7; 06-23-16 at 12:50 AM.
06-23-16, 11:13 AM
#33
This year Slipstream is trying something different with the classes here on the East Coast. AWD and RWD will have different classes and there are classes based on weight. It's not completely broken down to several classes it's mostly been done to seperate the GT-R's. The N/A class is interesting. If the 4 rotor were N/A it might be able to dominate that
What do you know about the classes in the events you plan to run Rob?
06-23-16, 11:58 AM
#34
Well, assuming that the car weighs 2800 pounds wet and has 1200 RWHP, that puts it at a power to weight ratio of 0.43.
A Nissan GTR at 2000 AWHP has a P/W ratio of 0.5
It also has the added benefit of traction to go with it. That's why they dominate, but provided the FD can hook and maintain as much power through a run, I don't see why it couldn't put forth a strong showing. The main issue I could predict is keeping the rear planted through a run and managing the torque of the engine as it spools up.
There is an article on MotoIQ where their RWD S13 Nissan with a 1.5L SR20 variant had difficulty keeping traction at speed. Now they were running on the salt and they run very skinny tires, so that is obviously a contributing factor. That being said, a 1200 WHP FD is a rocket ship at spped, hell even at 500 WHP people get into trouble.
A Nissan GTR at 2000 AWHP has a P/W ratio of 0.5
It also has the added benefit of traction to go with it. That's why they dominate, but provided the FD can hook and maintain as much power through a run, I don't see why it couldn't put forth a strong showing. The main issue I could predict is keeping the rear planted through a run and managing the torque of the engine as it spools up.
There is an article on MotoIQ where their RWD S13 Nissan with a 1.5L SR20 variant had difficulty keeping traction at speed. Now they were running on the salt and they run very skinny tires, so that is obviously a contributing factor. That being said, a 1200 WHP FD is a rocket ship at spped, hell even at 500 WHP people get into trouble.
06-23-16, 02:39 PM
#36
Rotary Enthusiast
1200hp is a TT gen 2 viper on low boost. (that you can buy for around 50-60k)
a Friend of mine just ran 214 at the Arkansas mile in his. (the only one in the top 10 that's not a "shop car")
https://www.usmileracing.com/full-results/?event=20
i think a TT viper is the proper "bench mark" for a turbo 4 rotor.
a Friend of mine just ran 214 at the Arkansas mile in his. (the only one in the top 10 that's not a "shop car")
https://www.usmileracing.com/full-results/?event=20
i think a TT viper is the proper "bench mark" for a turbo 4 rotor.
06-23-16, 07:43 PM
#37
Should be a nutty combo when finished. You need boost by gear dialed and TC to even try to manage that power. The FD has great aero and small frontal area on its side. The TX drag strip for TX2K is super well prepped with VHT compound. So that would be the best place to run for a RWD car for sure...
Most of the airstrip events have poor surfaces with pebbles/dust etc and zero VHT anywhere. I can't put down full power until 4th gear if not 5th. I can spin the tires in 5th gear at 180mph big time. I only have boost by gear. 1st gear 8-10psi (750rwhp), 2nd 10-12psi (950), 3rd gear 12-14psi (1050), 4th around 18-19psi and 5th 20-22psi. Traction is the problem.
A vented hood helps with stability big time. An undertray needed also. Smallest width front tire allowed. I run a 235mm front and 275/50/15 M/T et street drag radial for 1/2 mile. Any other tire doesn't put the power down very well. There is a trade off between tire pressure being low for max traction.... Or higher for more stability at 185mph+ And less traction. I prefer more stability. Also after your run don't stab the brakes .... Ease into them to not unsettle the car.
Awd High HP GTR and Gallardos you can't compete unless they are low HP builds. They can put down the power everywhere. I only beat RWD converted TTGallardos
!
Most of the airstrip events have poor surfaces with pebbles/dust etc and zero VHT anywhere. I can't put down full power until 4th gear if not 5th. I can spin the tires in 5th gear at 180mph big time. I only have boost by gear. 1st gear 8-10psi (750rwhp), 2nd 10-12psi (950), 3rd gear 12-14psi (1050), 4th around 18-19psi and 5th 20-22psi. Traction is the problem.
A vented hood helps with stability big time. An undertray needed also. Smallest width front tire allowed. I run a 235mm front and 275/50/15 M/T et street drag radial for 1/2 mile. Any other tire doesn't put the power down very well. There is a trade off between tire pressure being low for max traction.... Or higher for more stability at 185mph+ And less traction. I prefer more stability. Also after your run don't stab the brakes .... Ease into them to not unsettle the car.
Awd High HP GTR and Gallardos you can't compete unless they are low HP builds. They can put down the power everywhere. I only beat RWD converted TTGallardos
!
Last edited by gnx7; 06-24-16 at 12:25 AM.
06-23-16, 10:26 PM
#38
Should be a nutty combo when finished. You need boost by gear dialed and TC to even try to manage that power. The FD has great aero and small frontal area on its side. The TX drag strip for TX2K is super well prepped with VHT compound. So that would be the best place to run for a RWD car for sure...
Most of the airstrip events have poor surfaces with pebbles/dust etc and zero VHT anywhere. I can't put down full power until 4th gear if not 5th. I can spin the tires in 5th gear at 180mph big time. I only have boost by gear. 1st gear 8-10psi (750rwhp), 2nd 10-12psi (950), 3rd gear 12-14psi (1050), 4th around 18-19psi and 5th 20-22psi. Traction is the problem.
A vented hood helps with stability big time. An undertray needed also. Smallest width front tire allowed also. I run a 235mm front and 275/50/15 M/T et street drag radial for 1/2 mile. Any other tire doesn't put the power down very well. There is a trade off between tire pressure being low for max traction.... Or higher for more stability at 185mph+ And less traction. I prefer more stability. Also after your run don't stab the brakes .... Ease into them to not unsettle the car.
Awd High HP GTR and Gallardos you can't compete unless they are low HP builds. They can put down the power everywhere. I only beat RWD converted Gallardos!
Most of the airstrip events have poor surfaces with pebbles/dust etc and zero VHT anywhere. I can't put down full power until 4th gear if not 5th. I can spin the tires in 5th gear at 180mph big time. I only have boost by gear. 1st gear 8-10psi (750rwhp), 2nd 10-12psi (950), 3rd gear 12-14psi (1050), 4th around 18-19psi and 5th 20-22psi. Traction is the problem.
A vented hood helps with stability big time. An undertray needed also. Smallest width front tire allowed also. I run a 235mm front and 275/50/15 M/T et street drag radial for 1/2 mile. Any other tire doesn't put the power down very well. There is a trade off between tire pressure being low for max traction.... Or higher for more stability at 185mph+ And less traction. I prefer more stability. Also after your run don't stab the brakes .... Ease into them to not unsettle the car.
Awd High HP GTR and Gallardos you can't compete unless they are low HP builds. They can put down the power everywhere. I only beat RWD converted Gallardos!
Bingo, setting up for Boost by Gear with traction control via VSS and ABS sensors, vented hood, and splitter, full body undertray, for these very reasons. This chassis already spins like a maniac above 700rwhp, traction/control of the car > hp at this point
Last edited by Monsterbox; 06-23-16 at 10:45 PM.
06-24-16, 12:31 AM
#39
So you are hearing it first here. My transmission is in the process of being built. I am doing some top secret things to it but the core box is a Holinger RD6 ( i love the initials) 6 sp dog ring engagement sequential transmission with pneumatic shifter. although im making sure i can swap between teh two. i just dont know where the shifter will go and i dont have to worry when its all concealed in the drivetrain for now. Gearing the car for 220+ not sure of my final gear ratios just yet. but an aquantance just set the standing half mile at 240 in his gallardo so thats a bit higher than i was intending to gear it haha. we shall see.
Regardless my intention is to get some mainstream attention to help afford pushing this platform to its limits. I wonder how much horsepower you can put to the rear tires before its absolutely too much in each gear.
06-28-16, 12:35 AM
#44
If you can crack 200mph being RWD you should be happy. 220mph is a pipe dream. There is a lot more to it than just raw power.......
Kong Chang's 1200rwhp+ 996TT RWD conversion Porsche with a sequential gearbox did a 205mph best pass at the Shift Sector 1/2 mile event; however there really isn't much more left in it simply due to not being AWD. His car has an advantage with the weight being all over the rear tires vs. our front engine layouts. That track is not prepared at all compared to a TX2K drag strip. I don't see a 2wd car going much beyond 200mph.
The Hollinger transmission is no joke. They are creme de la creme. Best trans out aside from the PPG sequential T56 as far as holding power in that configuration.
Here is a 1971 Triumph with radically altered front end doing 387mph with a FWD turbo V8! Stupid fast..... just for entertainment! Small frontal area FTW
Kong Chang's 1200rwhp+ 996TT RWD conversion Porsche with a sequential gearbox did a 205mph best pass at the Shift Sector 1/2 mile event; however there really isn't much more left in it simply due to not being AWD. His car has an advantage with the weight being all over the rear tires vs. our front engine layouts. That track is not prepared at all compared to a TX2K drag strip. I don't see a 2wd car going much beyond 200mph.
The Hollinger transmission is no joke. They are creme de la creme. Best trans out aside from the PPG sequential T56 as far as holding power in that configuration.
Here is a 1971 Triumph with radically altered front end doing 387mph with a FWD turbo V8! Stupid fast..... just for entertainment! Small frontal area FTW
Last edited by gnx7; 06-28-16 at 01:01 AM.
09-06-16, 04:46 PM
#45
As we get closer to unveiling the concept at SEMA, i have some shiny expensive things to share. The Holinger RD6 dummy box has been in for a bit. I got the FD bellhousing adapter machined for the RD6. Its a piece of art in its own right. We also had Promaz machine a custom steel bellhousing based off the turbo 2 design. That should hold the power, protect my legs, and make room for the massive clutch. It is billet steel and only weighs 23 lbs.
The machine work is what makes this car so unique. I have quite a bit more being machined in North Carolina right now, but its cutting it close to the deadline. Ive had this concept planned for 2 years but like anything it doesn't really take off until the last second.
The machine work is what makes this car so unique. I have quite a bit more being machined in North Carolina right now, but its cutting it close to the deadline. Ive had this concept planned for 2 years but like anything it doesn't really take off until the last second.
09-11-16, 04:32 PM
#47
My goal 2 years ago was to make the most insane legendary car. I didn't realize how expensive that would be. Haha. I can't have everything.
It is pretty cool as I explain my vision of this car to vendors they have given me extra support and put their own twist on solving the challenge at hand.
I didn't mention it here but I'll be unveiling it at SEMA in the Garrett Turbo booth. It won't be a running car lol. But it sure as hell will showcase the unique things I'm doing to support and utilize the amount of hp this car will produce.
I've been tight lipped this far as I don't want to make claims and come up empty handed. That's soul crushing. But at this point I can safely say all that machine work pays off to make this a balanced rx7 on steroids.
It is pretty cool as I explain my vision of this car to vendors they have given me extra support and put their own twist on solving the challenge at hand.
I didn't mention it here but I'll be unveiling it at SEMA in the Garrett Turbo booth. It won't be a running car lol. But it sure as hell will showcase the unique things I'm doing to support and utilize the amount of hp this car will produce.
I've been tight lipped this far as I don't want to make claims and come up empty handed. That's soul crushing. But at this point I can safely say all that machine work pays off to make this a balanced rx7 on steroids.
09-12-16, 08:15 PM
#50
billet blocks
the are proven, that is what all the top rotaries setting world records are running. Cars like Loquito Killer, Major League, PAC ect are all running all billet or most of the parts are billet. congrats on the progress.