MZR swap
#101
How is the 2.5 getting 300 h.p?? I have a 3.0 durtec which from my understanding is same engine. This seems like the easiest swap to do. Either get Miata subframe or 2 RH engine mounts from an Rx8 ??? I love this swap because from bellhousing back nithnot changes. I plan to follow this swap & use megasquirts as soltion.?
#102
The 3.0 is an ancient V6. The 2.5 is a modern 4 cylinder.
There are many changes required to make it fit with the stock firewall. The stock transmissions from the RX8 and MX5 don't work.
There are many changes required to make it fit with the stock firewall. The stock transmissions from the RX8 and MX5 don't work.
#104
#106
#107
MZR 2.5L turbo first fire up.
It's worth noting that the firewall has not been cut or hammered at all in this installation unlike the other MZR installs that I've seen.
https://www.youtube.com/watch?v=PNg43DdwjYA
It's worth noting that the firewall has not been cut or hammered at all in this installation unlike the other MZR installs that I've seen.
https://www.youtube.com/watch?v=PNg43DdwjYA
The following users liked this post:
NotAPreppie (01-26-2019)
#110
The MZR is a great engine. The 2.5 was installed in hundreds of thousands of cars in the US and it's very strong internally, very light, relatively compact and has a strong aftermarket following.
#112
#114
Smoking turbo yay
I don't doubt it can that make much power, but do you like a lot of lag as well?
You also know a lot about LS already and how to make reliable power out of it.
#115
If I were just building a track car with no rule set guiding the decisions, I probably would have gone the LS route.
#116
What am I doing here?
Join Date: Mar 2006
Location: 2017 Miata RF Launch Edition
Posts: 3,606
Received 649 Likes
on
510 Posts
Yah, I'm still a couple of years off on starting my swap so it will depend where I'm at.
It's just nice to know that there's another option that's been done.
It's just nice to know that there's another option that's been done.
Last edited by NotAPreppie; 02-06-2019 at 10:35 AM.
#120
Registered
I plan to do OE looking swap and keep FSTB etc.
For those wondering, NC Miata supercharger kits are out of production. Soon the ND Miata kits will follow to extinction. Good-Win Racing is selling the last of ND supercharger kits for $3880 shipped on discount until Noon PST 30 AUG 19. When they are gone they are gone. Many are envious of my NC with FMSC kit.
I recommend getting the ND kit while there. ND makes more power than NC with 181 HP on 2019+ stock.
Who knows, ND SkyActiv-G might just swap right into the RX-8 as well! their 2.5L version makes 185 HP and 185 FT-LB right out of factory at 6,000 RPM. Bump the cams and springs, you'll see over 7,500 RPM and more at the wheel before boost with the supercharger.
Last edited by Soravia; 08-28-2019 at 11:03 PM.
#123
Registered
Each their own purpose.There's ND, NC turbo kits out there for people who want dyno charts and 0-60 numbers. They can dole out lots of power for sure. SC are for DD people who want throttle response.
I want 2.5L MZR (NOT the DISI from Speed) in the RX-8 for the DD reasons. Much more lower to mid torque to push the car with people in it. I can rev all the way to 7,500 RPM with OE springs and more if I upgrade springs and destroke to 2.3L for reduced piston speed, for the sports car feel. Stock 2.5L will run out of breath at 6,000 RPM.
And of course, I can swap the RENESIS over with sub frame, wiring, and all the ECU parts over to the NC Miata (minus steering , to get the high revving feel in it without so much torque for the tires. Imagine a 400 lb or so lighter Honda S2K.
As for SC power limitations, just saw a CTS-V coupe dyno at 875 wHP with Flex-Fuel (about 70% mix I bet). Probably smaller pulley, too.
Last edited by Soravia; 08-29-2019 at 12:37 PM.
#124
I haven't been paying much attention to this thread and I probably won't continue with regular updates moving forward but I wanted to respond to this.
1) Yes, you could probably move the engine further forward and reduce the amount of cowl cutting, but I think you would still have to cut the cowl. And then finding a gearbox solution would be much harder. I didn't do that because it defeats the purpose of this car, which is to optimize the weight of the drivetrain for handling.
2) I contemplated a supercharger setup, but none of the off the shelf ones were remotely appealing. Why? Well the Roots-type SC kits don't make nearly enough power, first of all. Second they are tremendously inefficient and put a lot of heat into the charge. Third they are heavy. If I were to go with a supercharger setup, a custom manifold with a Whipple (screw) type supercharger would work. But another downside to superchargers is they are very hard on the engine. They put a huge radial load onto the crank which is hard on bearings.
In the end, the turbo has worked out very well. With a set of cams the 2.5L easily breathes to 8,000 RPM, which is okay for brief periods with valve springs and stronger rods. I've been revving the stock motor to 7,400, with a set of mild aftermarket cams. The powerband and power delivery of the turbo is great for autocross, because of how responsive the turbo is with this engine. And yes, 400+whp is very driveable off of corners, at least with the big sticky Hoosier tires. You simply cannot approach the powerband of my setup using a supercharger. It will make half the torque at 4,000 RPM compared to my setup.
As I move towards a more racing-oriented gearbox for next season I will have my existing setup just kind of sitting on the shelf. Bellhousing, clutch, release bearing, FD gearbox, mount and the driveshaft. I have contemplated more than once building an emissions-compliant clone of this car with a smaller turbo and around 300hp at the wheels and this driveline setup would be perfect for that. If someone was interested in purchasing it from me I'd strongly consider that, to help fund the next phase of this car.
1) Yes, you could probably move the engine further forward and reduce the amount of cowl cutting, but I think you would still have to cut the cowl. And then finding a gearbox solution would be much harder. I didn't do that because it defeats the purpose of this car, which is to optimize the weight of the drivetrain for handling.
2) I contemplated a supercharger setup, but none of the off the shelf ones were remotely appealing. Why? Well the Roots-type SC kits don't make nearly enough power, first of all. Second they are tremendously inefficient and put a lot of heat into the charge. Third they are heavy. If I were to go with a supercharger setup, a custom manifold with a Whipple (screw) type supercharger would work. But another downside to superchargers is they are very hard on the engine. They put a huge radial load onto the crank which is hard on bearings.
In the end, the turbo has worked out very well. With a set of cams the 2.5L easily breathes to 8,000 RPM, which is okay for brief periods with valve springs and stronger rods. I've been revving the stock motor to 7,400, with a set of mild aftermarket cams. The powerband and power delivery of the turbo is great for autocross, because of how responsive the turbo is with this engine. And yes, 400+whp is very driveable off of corners, at least with the big sticky Hoosier tires. You simply cannot approach the powerband of my setup using a supercharger. It will make half the torque at 4,000 RPM compared to my setup.
As I move towards a more racing-oriented gearbox for next season I will have my existing setup just kind of sitting on the shelf. Bellhousing, clutch, release bearing, FD gearbox, mount and the driveshaft. I have contemplated more than once building an emissions-compliant clone of this car with a smaller turbo and around 300hp at the wheels and this driveline setup would be perfect for that. If someone was interested in purchasing it from me I'd strongly consider that, to help fund the next phase of this car.
Last edited by John V; 09-16-2019 at 11:01 AM.
The following users liked this post:
9krpmrx8 (09-24-2019)
#125
Boosted Kiwi
iTrader: (2)
Oh, really? But how much can you put down on the tarmac on DD car with DD tires? I'm already breaking traction all the time and have to stay below 65% throttle on my SC car with ONLY 225 wHP. Everytime I go full throttle, the rear hops and DSC kicks in even on dry pavement, 1st through 3rd gear.
.
.