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Old 10-23-2012, 06:57 AM
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our cars make peak power around 8400rpm iirc
Old 10-23-2012, 07:00 AM
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Originally Posted by alexevans
Help!!! acceleration problem power increase at 7500rpm

Only had my 04 231hp RX8 for about 2 months and never even noticed a problem until watching some videos on youtube etc and other rx8's accelerating. It can only be described as having even power right the way through to 7500rpm and then a real power surge/ powerband right through to redline in every gear. (very similar to Honda's Type-R engine) Thought this was normal as not had an RX8 before :/ Now startiing to wonder if it is really underpowered and only getting full power at 7500rpm???
Coil packs, plugs etc changed only 2000miles ago. No engine management lights or anything?? Car is on 04 plate, 52kmiles and FSH. Please help guys - new to this thanks

Apologies if i have posted this in the wrong section or has been discussed before but spent hours trying to find a similar problem but to no avail !
Is your car an auto? tbh theres no reason to go above 8500, we stop making beneficial power at that point and its not worth getting the engine that hot.

If you have an auto, the auto's dont go up to 9k rpm, mazda lowered the power/rpm due to the lack of a (or lack of inexpensive) auto trans capable of withstanding 9k rpm.
Old 10-23-2012, 07:15 AM
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He has a thread here too that I responded to: https://www.rx8club.com/tech-garage-...8/#post4371660

And given that he is in the UK with the hi-power option, it's a manual, so 9k rpm. And he isn't describing a power loss up high, it's a lower power loss with a sudden surge. Our engines don't surge at any point in normal operation. I suspect it's a problem with the ECU, open loop vs closed loop. Probably running way lean for too long under closed loop, ECU not adding enough fuel, and he hits 7,500, the ECU kicks him over to open loop finally where he gets the fuel he needs, introducing a surge.
Old 10-23-2012, 08:26 AM
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Ever since I replaced the motor mounts in my car, I get a rattle from the glove box when braking. I guess maybe my car vibrates a bit more when I hit the brake.

Anyways, I looked through the DIY section and found people with the same issue, but not really a "how to fix it" post.

If I open up the glovebox, the rattle stops. Any recommendations for things to put at the connection points that may work wellas a buffer?
Old 10-23-2012, 08:32 AM
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Just to clarify guys, its a manual 04 plate, 231bhp. hope this helps.... going to look into the ecu suggestion as a starting point. I have access to garage facilities to plug in diagnostic equipment as well. Just worried now as i thought it was just like a type r engine?!?! obviously not
Any help is much appreciated. thanks again.
Old 10-23-2012, 05:50 PM
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There are 2 basic engines that were used for the early RX-8s, 4 port and 6 port. The 6-port was called the "Hi-Power" in Europe when mated with the 6 speed manual, and had a 9,000rpm redline. The lower HP 5-speed manual had a lower redline (8,000 I think). Still lower was the automatic with the 4-port engine and a 7,500rpm. I am honestly not sure if the 5 speed manual had a 4-port or 6-port engine, or even if both were possible.
Old 10-23-2012, 07:40 PM
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damn boxer heads,

Anyways an enigneer at work today starting discussing why his STI is better than an Rx8. Thermal efficiency was brought up which i understand but according to him average sports car average around 25-28% but Wankel's are lucky to hit 18% efficiency. Any evidence to back this up I honestly never put much thought into expect for the fact that I am aware i have a 1.3L that puts out about 1.21gigawatts of heat. So i didn't think his assumptions were completely out of perspective.
Old 10-23-2012, 08:33 PM
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Not sure of the numbers, but yes, the thermal efficiency of a rotary sucks. It's why we have emissions trouble, mileage trouble, so much more air for the power, and run so hot. Rotaries are great for mechanical efficiency of a combustion, but poor thermal efficiency.
Old 10-24-2012, 07:14 AM
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Originally Posted by Carbon8
damn boxer heads,

Anyways an enigneer at work today starting discussing why his STI is better than an Rx8. Thermal efficiency was brought up which i understand but according to him average sports car average around 25-28% but Wankel's are lucky to hit 18% efficiency. Any evidence to back this up I honestly never put much thought into expect for the fact that I am aware i have a 1.3L that puts out about 1.21gigawatts of heat. So i didn't think his assumptions were completely out of perspective.
Yes but he drives a modified economy car that hasn't improved on the benchmark it set in 2004 when it came to north america.
Old 10-24-2012, 08:35 AM
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Originally Posted by Brettus
so why are RX7s faster than RX8s ?
They were made with different intentions. RX7 was made to be an all out performance beast and therefore was not very efficient and "environmentally friendly". The RX8 was made to be a decent sport car that you could use every day, pass the emmisions test standards at the time, and have some sort of fuel efficiency.
Old 10-24-2012, 08:43 AM
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Originally Posted by RotorRoar
They were made with different intentions. RX7 was made to be an all out performance beast and therefore was not very efficient and "environmentally friendly". The RX8 was made to be a decent sport car that you could use every day, pass the emmisions test standards at the time, and have some sort of fuel efficiency.
Did he just try to school the Brettspeed?
Old 10-24-2012, 03:23 PM
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Originally Posted by RotorRoar
They were made with different intentions. RX7 was made to be an all out performance beast and therefore was not very efficient and "environmentally friendly". The RX8 was made to be a decent sport car that you could use every day, pass the emmisions test standards at the time, and have some sort of fuel efficiency.
Old 10-24-2012, 04:01 PM
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Yes he did just answer a two year old sarcastic post.
Old 10-24-2012, 06:45 PM
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Originally Posted by Unoriginalusername
Yes but he drives a modified economy car that hasn't improved on the benchmark it set in 2004 when it came to north america.
Most would argue 8's haven't improved since 2004, minor tweaks but still in all actuality we went backwards 8's died. 2013 STI vs 2013RX??????
Old 10-24-2012, 07:08 PM
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Really Subaru hasn't changed anything in 15 years beyond making more efficient power. They continue to sell them and people continue to buy them.
Old 10-24-2012, 08:41 PM
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Hey guys, here's a 'dumb' question for you.. What is the common failure mode of the 04/05 engines? Looking for my 8 and I'm wondering if I should even bother looking at an 04 or 05?

I've found an 04 with 30k miles on it and a reasonable price.. If it passes a compression test, can I assume the engine is 'good'? Or do those engines tend to go along just fine and then randomly blow up one day?

Thanks in advance!
Old 10-24-2012, 11:54 PM
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Dumb Question- Why would you pay to have the BHR midpipe polished? Wouldn't it just get dirty from the exhaust anyways?
Old 10-25-2012, 10:01 AM
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Originally Posted by ZiG
Hey guys, here's a 'dumb' question for you.. What is the common failure mode of the 04/05 engines? Looking for my 8 and I'm wondering if I should even bother looking at an 04 or 05?

I've found an 04 with 30k miles on it and a reasonable price.. If it passes a compression test, can I assume the engine is 'good'? Or do those engines tend to go along just fine and then randomly blow up one day?

Thanks in advance!
Read the sticky threads. There's an explanation of why the engines failed on those models.

Should you bother looking at an 04/05?
In my opinion, no. It's a crap shoot. You could get a decent car for an extremely reasonable price, or you could end up with a lemon thats just a money pit until you get frustrated and sell it.

If you do happen to look at 1, make sure you listen to every little sound it makes, because problems snowball on the car. If it passes compression, great, doesnt mean it wont lose it once you drive it. Try to snag one with a bit of the 8 yr 100k mile warranty on the engine.

Look at 06s and up though imo.
Old 10-25-2012, 10:02 AM
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Question:

Where can I get a replacement cap for the A/C valve where you would insert freon?

I checked onlinemazdaparts but didnt see the cap there.
Old 10-25-2012, 10:33 AM
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I believe they are universal among all cars if it is the thread on cap.
Old 10-25-2012, 10:34 AM
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Originally Posted by Raves44
Dumb Question- Why would you pay to have the BHR midpipe polished? Wouldn't it just get dirty from the exhaust anyways?
Because you want it to look pretty. The unpolished one is pretty shiny as well. Mine still looks good 4 months later.
Old 10-25-2012, 02:03 PM
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build number

Where can i find out what number car my 2005 shinka is? for example number 156 of 1400 built.
Old 10-25-2012, 02:08 PM
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i would to know if any 8's meet up in the El Paso / Las Cruces area. help yo
Old 10-25-2012, 02:11 PM
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Originally Posted by ThatNewKid
Where can i find out what number car my 2005 shinka is? for example number 156 of 1400 built.
There is a 2005 production list around the site somewhere.... hmm

Edit: Here: https://www.rx8club.com/rx-8-discuss...-vin-s-166370/

Originally Posted by frankdux v chung li
i would to know if any 8's meet up in the El Paso / Las Cruces area. help yo
How about checking the regional subforum?
Old 10-25-2012, 10:44 PM
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Originally Posted by jamesf
Read the sticky threads. There's an explanation of why the engines failed on those models.

Should you bother looking at an 04/05?
In my opinion, no. It's a crap shoot. You could get a decent car for an extremely reasonable price, or you could end up with a lemon thats just a money pit until you get frustrated and sell it.

If you do happen to look at 1, make sure you listen to every little sound it makes, because problems snowball on the car. If it passes compression, great, doesnt mean it wont lose it once you drive it. Try to snag one with a bit of the 8 yr 100k mile warranty on the engine.

Look at 06s and up though imo.

Ok, thanks. I re-read the new owners sticky, and had fogotten about a couple things including that recall to increase the oil usage. I'm still giving preference to 06+ but there are a few 05's that look pretty tempting right now. There's also an 07 with only 20k on it, but I'm wary of that one because of the mileage being so low...


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