Charles R. Hill

iTrader: (7)

I think this is what Pettit meant by "backhousing ratio";
https://www.google.com/#q=turbo+back+pressure+ratio

Given what happens to the Renesis when the coils are weak enough to begin ruining the catalyst, I think we can see how backpressure and overheating the side seals and corner seals can be of concern. Whether or not enough backpressure is created using the Greddy Turbine wheel/housing to cause damage, I guess remains to be debated.

skc

My car has been running on a stock 10 year old engine. The last 3 have been supercharged with several track days since supercharged and close to 100 track days in total. Car seems to be going strong and now being used as a daily driver.

I even had several hiccups as I am the only car that is running the Hymee supercharger and despite the challenges the engine is still holding up.

The stock engine is quite strong if driven correctly.

FazdaRX_8

iTrader: (1)

Be content, enjoy the car the way it is.

cpet

Yes, it can take u-turns like no ones business. Just don't rev your engine next to, well, almost any other car. lol

It does handle great, and it looks great, but it was definitely never built for speed. It's unreal how much is unknown about this car even by most of its owners.

I've already decided I'm just going to have the engine rebuilt and then put a turbo on it. It's a coin toss with these rotaries.

I wish the car at least had more torque.

Slidin8

Mate rotarys love getting revved up high, low rev driving actually kills them.

So many rookies here

cpet

Yeah I won't be doing that. Like most people on this forum I'll pay someone who actually knows something about this car to do it. It's funny how people say they've learned so much on this forum and then in the next sentence say they are waiting on the shop to finish the work being done to their RX8. In other words, they don't work on their own car, they pay someone else to. Of course they do, I would too.

I wouldn't even post a failed engine thread. I would know I was told, by every other person. One persons is successfully, reasons unknown, two others fail, reasons unknown. The only thing we have to go on is "we told you."

Most people post theories on why this engine fails. I haven't seen facts yet.

cpet

By rev my engine, I mean you're at a stop light next to say a Mustang GT with over 300 HP, and you rev your engine indicating you want to race the GT. You and I both know how that situation ends up.

You can hit 9,000 rpm all you want. You'll still be taken by that Mustang.

The RX8 needs FI. I have no idea why this design left the factory without it. Esp when most other cars naturally aspirated have over 300 HP these days.

Edit: Yes, I do love the car, I just wish it had more HP, more torque, and more displacement. All of those stock specs on the RX8 are too low. I love the car enough to dump $15K into it to fix what Mazda obviously could not.

RIWWP

iTrader: (2)

The facts are sitting out there for those of us that have seen the threads being posted for years. Someone doesn't upgrade their cooling system and blows a coolant seal. Someone else doesn't wait for a proper tune and shatters apex seals, someone else nudges the boost a bit and shatters seals. Someone else uses an emanage and as soon as the factory ECU corrects the tune enough, boom goes the engine. Someone else tries boosting an old engine and it can't handle it. Someone else has everything right and tries for 400whp and cracks the block. Soemone else uses the wrong MAF tube size and can't get the tune right and the engine blows. Someone else has a fuel line pop off on the track and the sudden lean spike blows the motor.

The information is all out there already. It's not our fault that you haven't read it all yet.

Yeah, we do. Someone arrested, someone else dead, and our car getting even more negative publicity on the media.

The RX-8 was already barely scraping in under the emissions requirements for Europe and the US. FI would have made it impossible to sell. FI would have also SIGNIFICANTLY increased warranty claims, which are already really high. FI would have driven the cost of the car another $5k-10k higher, which would have crippled sales even more.

Plenty of reasons why it never had FI from the factory, and Mazda was RIGHT in making that decision. The people that want FI on it can do so without any increase in warranty claims, they can deal with emissions laws on their own that Mazda won't be responsible for, and they can spend all the time R+Ding it themselves that Mazda doesn't have to pay for.

And no, the RX-8 doesn't 'need' FI. You just want more power from it. That is acceptable and understandable, but the vast majority of owners out there find it is fast enough without it.

I remember Flashwing's turbo'ed 8. He tracked it periodically. Then he got a Mazda2 for use as a daily. One day he took the stock 100 crank hp 2 to the track instead, and beat his turbo 8's lap times. If you think a stock 8 is underpowered, you should drive a 2. I've got one in the garage so I know exactly how underpowered it is. But yet.....?



I'm not trying to convince you to not go FI. By all means, have at it. I'm just countering some of the flawed reasoning that you have.

04Green

iTrader: (1)

SKC was the first supercharger to post. If you want power, look hard at that too. OD did it, ROT8 did it. They ran into some engine issues, but I think they were exploring the outer edges of possible. I believe they both had Petit supercharger kits. The supercharger solves the back pressure problem.

Or, check out the Pettit thread on this site.

cpet

Thanks 04Green. At least your response contained information I can follow. I'll check it out.

rickeo

iTrader: (1)

After this one, I wouldn't bother any more RIWWP...

mod edit:
Removed your last sentance, it isn't needed here
-RIWWP

cpet

It's people like you that make using these forums impossible. I have read through every "read this first" post and I've followed plenty.

It's not that I didn't understand someones opinion. It's that I simply registered it as that - an opinion.

We have no emissions testing in FL. I can take the cat converter OFF and no one would care to stop me. My car could blow smoke and fire out of it's *** and no one in this state would care. Your situation doesn't necessarily apply to me.

You can lock this thread. I have no intentions on entertaining posters like rickeo further.

ShellDude

iTrader: (12)

cpet, your approach and demeanor in this thread is pretty lame. If this is a sign of how things are going to be perhaps you should consider moving on.

Might I suggest the civic forums...

Brettus

iTrader: (2)

niteshade247

You can lead a horse to water but you need a really big $!&@ing stick to make him drink.

skc

A well tuned FI engine should last a long time. Naturally, it is a good idea to stay on top of your maintenance if you go FI as the car is under more stress than usual so if maintenance is neglected then it could easily lead to failure.

My power output is close to 270hp at the wheels which is quite conservative to some. However, I have not pushed the envelope as I still run the stock radiator and oil cooler. More power will lead to more heat. The current cooling setup only shows its weakness at the track.

So if you want more power than you will need to upgrade the cooling system.

You will also be using more fuel if you go FI.

Charles R. Hill

iTrader: (7)

The RX-8 is one of the best-tuned vehicles off the showroom floor, which is why it does so well in the amateur racing classes where the cars must remain close to stock. Car and Driver opined the braking system to be "one of the best in the world, regardless of vehicle price". With a only a few proper mods, one can slightly improve it's performance, but you better know exactly WHY said mods are to be done or you will only make matters worse.

The key to exploiting the RX-8's capabilities are to be a capable driver and learn how to keep the engine between 6,000-9,000 RPMs while driving it in a spirited fashion.

Charles R. Hill

iTrader: (7)

Read enough through the archives here and you will see what many of us have been doing for the past 10+ years.

Charles R. Hill

iTrader: (7)

The Mustang and the RX-8 were designed for two different types of drivers, which is why a good driver in an RX-8 will eventually beat a Mustang on, oh, let's say, Road Atlanta when the Mustang driver becomes frustrated by seeing a "lowly" RX-8 in his mirrors through every turn. Sure, the Mustang will walk away on the back straight, but only to see that RX-8 right back on his *** as soon as the Mustang hits the brakes (way too early before the turn, I might add).

The RX-8 is a driver's car and Mustangs are a musclehead's car. I worked for Ford when I bought my RX-8 and I could have purchased a really nice Mustang, brand-new, for far less than I paid for my RX-8. My father learned why when I took him for a ride in my RX-8.

The bottom line here is that you are a very new RX-8 owner, and most of us on this forum welcome your arrival. Please keep in mind that many of us have owned our RX-8s for a LONG time, and some of us have been very involved in discovering the strengths and weaknesses of it. We are not here to cast doubt or to bash your decisions, but we would appreciate if you kept in mind that some of us do know what we are talking about and we are only trying to help you.

The hard part, for you, will be to determine whose opinions you prefer and whose you do not.

Brettus

iTrader: (2)

You forgot the bit where the mustang driver loses it and ends up upside down in the kitty litter.

I8yourv8

I've come to realize its not only cheaper to swap to a LS1, but more reliable and more powerful. Thats what I plan to do in my future. These cars will be 12 second or faster with a stock LS engine.

RIWWP

iTrader: (2)

Cheaper than..........what?

Make sure you pick a comparison point that is under $30,000.

I8yourv8

either swapping, or turboing the renesis

RIWWP

iTrader: (2)

As expensive as turbo'ing the Renesis is, it's a lot cheaper than redesigning and then rebuilding the entire front of the chassis frame plus rewiring every single piece of electronics in the car ... which is what you essentially have to do with a swap of any piston engine.

Carbon8

iTrader: (4)

A reliable FI job can be done under 10K if you know what you are doing.