paimon.soror

iTrader: (15)

FC/FD and Renesis .. two completely different engines thanks to two completely different implementations which have two completely different sensitivities to a turbo.

It isn't that it hasn't been explored ... it is that the shortcomings of the renny platform are preventing people from harnessing the true benefits of turbocharging without significant risk.

RIWWP

iTrader: (2)

Yes, pushing more power through ANY engine will reduce it's life span. Simple thermodynamics, heat stresses, wear, etc...

However, not all engines are created equal. Pushing 50% more power through a rotary is a vastly different lifespan change than pushing 50% more power through an Evo block for example.

Even between the FD and the RX-8, there is a huge difference. This is due to the design differences between the two engines.

It's not that there "hasn't been enough exploration", because there actually has been quite a bit. The problem is 2 fold:

1) On a stock engine, the side seal springs overheat and deform with higher EGTs. You can get this WITHOUT turbocharging, and turbocharging is significantly higher EGTs than N/A. No matter what else you do to the turbo hardware, the tune, etc..., you come up against this wall of dealing with EGTs and side seal heat.

2) The only possible way around the side seal problem will INEVITABLY mean that you have to redesign the engine to some degree. Even if someone actually figures out a good solution and has it "solved", it will mean MANDATORY engine rebuilds with custom work (think $10,000+ engines minimum) to solve the problem on that engine too.


Sure, it may be solveable, but the costs are already significant, and any possible solution will only drive that cost up further. A LOT further. A solid turbocharged setup with a properly built engine is already only a few thousand off of what it costs for a turn-key FD REW swap. If it gets much higher, you will be close to an N/A 20B swap cost...

At what point is it still worth it? We pretty much already left that point behind years ago.

9krpmrx8

iTrader: (46)

Whether it is worth it or not to someone depends on many things. It has been a long haul for me and has cost a ton of money to get my car to where it is now.

But, there is nothing like a well running turbocharged RX-8. It is awesome and it's not just about horsepower figures. I am in heaven right now with my turbocharged RX-8 tuned properly and running well. But my RX-8 is paid off, I don't put many miles on it, and I have the means and the ability to fix it WHEN it breaks AGAIN.

RIWWP

iTrader: (2)

Clarification:
"Worth it" was meant as a comparison vs other big power options. Definitely the actual result being worth it is dependant on each owner's capacity, motivation, and goals.

9krpmrx8

iTrader: (46)

I gotcha, I just have many friends and family who just have never gotten my obsession with having fats cars with small engines, So they just cannot compute how I think all the time, trouble, and money is worth it.

RIWWP

iTrader: (2)

I hear ya.

I figure that if someone "solves" the side seal issue from EGTs, people would be looking at $15,000(or more) to implement that plus a solid turbo setup on an otherwise stock RX-8. At that point, I would say that it isn't worth doing vs an REW swap, and may not be worth it vs an N/A 20B swap.

So it basically means that any solution found for our critically weak points would have to be essentially "free" (in terms of net overall cost), and I don't see that happening.

ShellDude

iTrader: (12)

RIWWP, give me a moment here. It's with the best of intent.

RX8UKNOOB, bite me. I totally object to your asinine comment. I'm fuking helping you out dude.

I told you two basic things:

1. If you buy a used turbo plan on rebuilding it
2. If you buy an unknown/unproven/widely known among the community to be crap setup turbo you are on your own.

I'm not your mother. I have zero accountability to you as an individual. You asked what to do and I'm telling you what my opinion is based on 5 years of experience on the RX8 platform. If you don't know my story, I could care the *** less. Read the various threads I've described my setup in (I actually have a few of them) and make up your own mind on whether you consider my opinion valuable or not.

I will say this -- after all, I am only answering your question...

I've got two turbos. The (3rd try is a charm) one in my RX8 now, and the built just for me, shipped directly from Trust brand spankin' new one in my garage in a nice cozy shipped from japan xxoo box waiting for my current one to crap out backup.

Where'd my current one come from? I bought it used from a fellow member here 4 years ago. It was sold "as new" and he's a decent guy, sold and delivered with the best of intentions.

Guess what... it crapped out after about a year... so what did I do? I warmed up to Bryan Nickels and had him do a rebuild.

Guess what happened about a year later? I lit up my neighborhood one morning heading out to work (you guessed it, my RX8 is also my daily driver) with a billow of smoke thicker than the worst fog we've ever received "naturally" here. Easily 1/4 mile from my driveway and back was engulfed in white smoke as it took me a 1/4 mile to realize I was dumping all my oil into my exhaust and lighting it up for all my neighbors, and their neighbors, to see before I turned around and came back home.

So what did I do? I called Bryan and he rebuilt it for me again. The cost of overnight shipping was more than he charged me for the rebuild... and rightly so as I took the time up front and went with someone who has demonstrated repeatedly high integrity.

And what did I do as I was waiting for Bryan to rebuild my turbo a second time? I worked out a special order directly from Trust for a brand spankin' new replacement in the event my 2nd rebuild ever craps out.

Which it will one day, no doubt.

Don't insult me with some obtuse notion that I'm a source to some obscure internet drama impacting your livelihood. A thank you would have been a much more appropriate response.

rx8uknoob

thanks guys but i was getting annoyed because 9krpmrx8 made a total meal of a simple question telling me how i need to do this and that when post 13 from shadycrew answered exactly what i wanted to know in the first place! and chillout shelldude all i was asking is why you prefer greddy, no need to be a dick about!

ShellDude

iTrader: (12)

Bullshit. I quoted your lame *** response.

LiveWire

iTrader: (1)

Well shucks I do agree! Sorry if I made it seem like I was comparing the two on engine/turbo compatibility. I was merely trying to encourage UK by comparing platform to platform. My point was merely that it is easy to see how strong the FD was in performance, so naturally people want to make the Rx8 (with arguably better handling) its successor in horsepower as well.

Anyway now that we are on the subject (yes I have searched to no avail). How much N/A power does a 20b make? Never could find it. Anywhere. With regards to turbo build/20b build are you comparing price/horsepower or just total price? Just wondering because the first comparison was between two turbo rotaries while the second wasn't. I'm mostly interested in the numbers if anyone has them.

RIWWP

iTrader: (2)

N/A peripheral port power is highly variable depending on the porting work done. A completely stock 20b is somewhere in the high 200s I believe. However, just as you can get an N/A 13B (peripheral port) north of 300 (I think north of 400 with severe loss of driveability), hitting 400whp on an N/A 20b is totally doable. The Grand Am RX-8s were 450hp N/A 20Bs, though i don't know if that was at the wheels or at the crank, and they used Renesis rotors for the higher compression.


Other people may have more specific / accurate information.

shadycrew31

iTrader: (6)

I was in a good mood...

paimon.soror

iTrader: (15)

many times, explaining a complex process in a simple way + noobs = disaster

take two steps back from the keyboard and realize that people were playing devils advocate here and trying to prevent what could be a rather expensive investment.

god forbid you were fed extra information for free

ShellDude

iTrader: (12)

I was drunk and am actually impressed with my restraint in hindsight.

shadycrew31

iTrader: (6)

In hindsight I realize I was intentionally trying to troll 9k by playing good cop. We joked about it tonight actually hahaha!

The newb got solid intel from both sides we shall see how this plays out.