400whp turbo setup from NZ

[Brettus]

This dyno was done back in February but I never got the proper printout of it till recently .
Turbo : Garrett G30-660 1.01
Manifold : custom fabricated log style low mount.
Engine: Renesis on E40 with rx7 apex seals and dowelled.
Exhaust : 3" main with separate WG exhaust
Intercooler : custom vertical row
Tune: myself using Mazdaedit
Power : 415whp @ 15psi

[Milos_Balunovic]

Bret, as always great work. the dyno sheet looks spot on

What is the reason for not revving it a above 7.5k ? turbo efficiency, engine efficiency or ?

as it seams to me even thought you're levering boost the torque is still climbing at that point

[Brettus]

These engines don't like that much boost past 7500 from a zoom zoom boom standpoint. I did have boost cut set at around 7300 but the dyno operator also set the dyno to finish the run at 7500 just to be on the safe side. I do run it at higher rpms on the street though.

[Milos_Balunovic]

so its exhaust port flow I suspect that is limiting the engine ?

[Brettus]

Yeah ... I actually wrote a thread on the issue on the rx8club.com forum ......

[Paul_13]

Yeah ... I actually wrote a thread on the issue on the rx8club.com forum ......

Do you have a link?

[Brettus]

Yeah ... I actually wrote a thread on the issue on the rx8club.com forum ......

Do you have a link?

https://www.rx8club.com/series-i-major- ... ry-268776/

[Milos_Balunovic]

Great effort Brett.

In 2T there is a "design" parameter called port time area. It takes in to acount the time of each part of the port being open and evaluates how much value it has. In 2T its simoles as rotation is easy to determine analitically and than calculate but thats not easy for a wankel.

This next part is just a brain f#rt so take it with a grain of salt
The only way we could make a renesis take more power (higher rpm) is by makin resonated 2T pipes to help the scavenging of the cylinder by creating a low pressure period aligned with "perfect" timing for best result (what ever it would be).

Having that is impossible anyway becouse of size limitations and cost of development exceeding any rew swap. Especially now that the rew core is awailable for purchase new from mazda.


Back to the OT of your findings. What is your thoughts on supercharger. Since it could be theoreticaly built with "zero" back pressure. Could it be more potential in it ? I "know" in turbo app that if the back pressure is same as boost its already considered a huge accomplishment and usually its higher than the boost.

Though 400whp with a low mount turbo is a sweet and "simole" setup that nobody should need anything further.

[Brettus]

Re supercharger .
Given the results we saw from the landspeed rx8 that made 650whp using a monster turbo and a few other mods, I'm guessing a large supercharger might have an advantage in making ultimate hp. But you would have to factor in the extra 100plus hp it would take to drive it, the added weight up high and what that does to center of gravity etc.

[WildMan10]

That’s impressive. Congratulations on your fine work. I hope she goes for a long time before any ‘zoom zoom boom’.

[Milos_Balunovic]

Re supercharger .
Given the results we saw from the landspeed rx8 that made 650whp using a monster turbo and a few other mods, I'm guessing a large supercharger might have an advantage in making ultimate hp. But you would have to factor in the extra 100plus hp it would take to drive it, the added weight up high and what that does to center of gravity etc.

Would you share max maf you are reading?
I suppose that value would be safe no matter the engine speed. (To reasonable limits of low rpm as that would drive the torque high)

[Brettus]

Would you share max maf you are reading?
I suppose that value would be safe no matter the engine speed. (To reasonable limits of low rpm as that would drive the torque high)

I have my maf scale increased by fitting resistors plus the number is very dependent on the tune etc so it's hard to do any comparisons. That said, grams/second line up pretty damn close with WHP in that dyno.

[Brettus]

Have now tested the new cast manifold for the G30-660 0.83 .
Spoolup is 400 or so rpm better than the 1.01 shown above and emap looks fine for taking it up to 400whp .

[Milos_Balunovic]

The only thing remaining is for ypu to send a samlle to me for a long term testing

Great worknas always and im impressed by your progress. Who would thought the new g series are so good flowing

[Brettus]

I think the new G series is still largely underestimated. People need to look at the actual flow specs and not pay any attention to the size of the wheels.

[Milos_Balunovic]

You're wasting you breath there, as we live in a world where most people think that a quarter-pound burger is bigger than a third-pound burger

[bigpete8]

4 is bigger than 3

[Brettus]

Reminds me of the time I ordered a 152mm sub at Subway.

[350matt]

I'm guessing you got a look like a dog being shown a card trick.......

[Brettus]

I'm guessing you got a look like a dog being shown a card trick.......

That about sums it up.

[SeriousSam]

This looks rather interesting Brett, I will be keeping my eye on this thread. Out of interest, has anyone done any testing of this particular turbo with an REW engine? I've been considering a turbo conversion for a little while, and what this might allow me to do is avoid the cost of an REW swap at this stage. If I were to later blow up the Renesis, then an REW swap with the same turbo might make a lot of sense and save a wedge of cash too. Thoughts?

[Brettus]

Hey Serious, there is a guy on the rx7forum who is using a G25-660 0.92 . Looking at his results it's suggesting that turbo is a little small for the REW (high backpressure) . I'm getting better results on the Renesis with the G30- 660 0.83 from what I can see.
IMO the G30-660 with the 1.06 twin scroll would work great on the REW for a quick spooling 350-400whp. So you would just need to do a turbine hsg change going from one engine to the other if that was the power range you would be happy with.

[Magsrx8]

Hey Brettus, whereabouts in NZ are you? I lived in Dunedin for nearly 7 years and miss it immensely.

You certainly know your stuff, this thread is good to read and mind blowing to a stock rx8 man like myself.

[Brettus]

Hi Mags ,thanks for that. It's been a bit of a ride to get to here but satisfying to finally be getting results.
I'm in Hamilton .

[SeriousSam]

Damn you Brett, now I'm really interested! The 300-350 range is where I've been thinking I'd like this car to end up, I want a really solid road car that can do a handful of track days each year, so that's an ideal range - perhaps one size smaller would suit my current goals, but that would give me some headroom for future improvements if I wanted to push it a bit further. Now I need to have one of those conversations with the wife...