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Where in the drivetrain is the RX-8 losing so much power?

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Old 06-11-2008 | 07:53 PM
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Where in the drivetrain is the RX-8 losing so much power?

Where in the drivetrain is the RX-8 losing so much power?

The RX-8 stock in top condition puts out 232hp at the crank, no? Yet only 175 or so ever make it to the wheels. Thats a 25% power loss.

What part/parts is/are eating so much power?
Old 06-11-2008 | 08:00 PM
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232 is wrong - sad but true .
Has been confirmed that actual output at the crank is 215-220hp .
Old 06-11-2008 | 08:10 PM
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Originally Posted by Brettus
232 is wrong - sad but true .
Has been confirmed that actual output at the crank is 215-220hp .
Fine. 20% loss.

Where is it?
Old 06-12-2008 | 10:10 AM
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The loss is in the marketing department. If they'd rate the engine according to what it actually does, the results would look so bad. The RX-8 drivetrain is no worse than any other car. You just don't have a 232 hp car.
Old 06-12-2008 | 12:17 PM
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^hahaha rotarygod
Old 06-12-2008 | 12:36 PM
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One of the few times that I'll differ from RG. I question the original numbers in 04 but I don't see the new standard being fudged as it has been applied after 06. The SAE isn't in bed with Mazda. A properly working 06 should be much more in the 190 range (Give or take) than 175.

The diff is heavy duty and much beefier than an S2000 for example.

Paul.

PS, I''ve been wrong before. So correct me if you think I'm in error.
Old 06-12-2008 | 12:54 PM
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the math calculates out to an engine with 215hp.

didnt someone put renny on an engine dyno and come out with 217hp? i swear i saw the dyno sheet. edit: i cant find it, but i swear i've seen it..
Old 06-12-2008 | 12:55 PM
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So how do you explain that JDM gets 250hp? Don't tell me a few octane better gas will net you over 20hp!!!
Old 06-12-2008 | 12:57 PM
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show me a dyno that the jdm gets 250. but as for now, i dont believe it.

edit: searched for 5 minutes, nothing. im pretty sure they get 250hp like i have 238hp.

also, if thats the case, why arent we seeing JDM flashes on our computer? that'd be a really cheap mod. also, wouldnt the AP net like 40hp, it would make up our loss to the jdm, then further improve that? and please no dynos like the one in this article. lol. http://motortrend.automotive.com/389...n/engines.html

Last edited by kersh4w; 06-12-2008 at 01:02 PM.
Old 06-12-2008 | 12:58 PM
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it's rated from factory.
Old 06-12-2008 | 01:03 PM
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do we believe the factory for the us-spec rx8s?
Old 06-12-2008 | 01:03 PM
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Originally Posted by delhi
So how do you explain that JDM gets 250hp? Don't tell me a few octane better gas will net you over 20hp!!!
That sounds like the old number and it is BS as well . Although they do have softer emmissions laws and use DIN hp (i think ) which gives a higher reading as compared to SAE .....
Old 06-12-2008 | 01:08 PM
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everything points to 215hp engines. face it, mazda lied.
Old 06-12-2008 | 01:10 PM
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I agree that you won't find any stock figures on planet earth making 250 but I need for someone to explain how the new SAE standard could be getting it wrong on the current cars. I think 232 is accurate.

Paul.
Old 06-12-2008 | 01:19 PM
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is'nt there a 5% tolerance ? Also , does SAE have all the belt driven ancillaries in or out of the numbers ?
Old 06-12-2008 | 01:29 PM
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it really depends on which way you use to measure the engine's power.

In Japan, its still the same 250ps, never changed. I remember the Spirit R was rated at 280ps, no one ever questioned that. Torque is a different story of course.
Old 06-12-2008 | 01:53 PM
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Originally Posted by nycgps
it really depends on which way you use to measure the engine's power.

In Japan, its still the same 250ps, never changed. I remember the Spirit R was rated at 280ps, no one ever questioned that. Torque is a different story of course.
The problem is that 250ps doesn't equal 232hp and the new rules applied in the US are super strict. All the drive belts must be attatched and there has to be SAE supervision in the process.

Paul.
Old 06-12-2008 | 02:00 PM
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if an american driver has an rx8 ... you immediatly loose 30 whp because of your fat ***! hehe join a gym ... problem solved

really... Ive always thaught the gearing in the 8 could be improved. I hear some one has a 5 speed meant for turbo applications... but Ive always wished some one would come out with an updated gearing setup to include a taller 6th gear and a different gear for the rear. just re work the entire thing.

my gearing expertise is really only in motorcycles... but it really has opened my eyes to see how much gearign plays a role in every aspect of not only launching , but control as well.
Old 06-12-2008 | 04:30 PM
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I have to agree with Paul; I'm not sure how Mazda would be able to work around the new SAE testing procedures to get inflated numbers.
Old 06-12-2008 | 04:54 PM
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I know for a fact that the engine CAN make 238 hp and in fact it CAN make more. What it DOES from the factory however doesn't seem to live up to those numbers.
Old 06-12-2008 | 05:07 PM
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Originally Posted by Brettus
That sounds like the old number and it is BS as well . Although they do have softer emmissions laws and use DIN hp (i think ) which gives a higher reading as compared to SAE .....
I agree. However it seemed the JDM boys think that their 'superior petrol' (RON vs. AKI so it's even the same). allowed it to make more hp than ours. Hence the discrepancies.
Old 06-12-2008 | 05:18 PM
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Could the hp difference have something to do with why some engines lose compression or go kaput very early? Might there be a connection? I remember when I first picked up my car (brand new 07) and being new to rotaries, I had a number of different people tell me how a rotary should be broken in? Drive it like you stole, burn rubber out of the dealership, etc. So, I followed Racing Beats break in procedure. At 7000 miles, I can feel the engine is stronger than when new. Could a simple break in procedure be the reason why some engines die an early death or don't put out advertised hp numbers?
Old 06-12-2008 | 05:18 PM
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Originally Posted by rotarygod
I know for a fact that the engine CAN make 238 hp and in fact it CAN make more. What it DOES from the factory however doesn't seem to live up to those numbers.
I hear you. I would actually pay to see a chassis dyno on the newest RX8 (Literally). I'd be surprised if it doesn't exceed 190.

Who'll participate in this exercise? I'll put my money where my mouth is.

Paul.
Old 06-12-2008 | 05:20 PM
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Originally Posted by RatedX8
Could the hp difference have something to do with why some engines lose compression or go kaput very early? Might there be a connection? I remember when I first picked up my car (brand new 07) and being new to rotaries, I had a number of different people tell me how a rotary should be broken in? Drive it like you stole, burn rubber out of the dealership, etc. So, I followed Racing Beats break in procedure. At 7000 miles, I can feel the engine is stronger than when new. Could a simple break in procedure be the reason why some engines die an early death or don't put out advertised hp numbers?
Makes ya think.
Old 06-12-2008 | 05:57 PM
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Originally Posted by Mazmart
I hear you. I would actually pay to see a chassis dyno on the newest RX8 (Literally). I'd be surprised if it doesn't exceed 190.

Who'll participate in this exercise? I'll put my money where my mouth is.

Paul.
what makes you think it will be any higher than the older models ?


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