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2010/2011 RX-7 Motortrend article

 
Old Jul 17, 2007 | 05:59 PM
  #101  
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Originally Posted by mac11
doesn't look like you need 300bhp to run 12's.
You're forgetting that the Spirit R Type A weighed in at a touch under 2700lbs.

I believe it also had 4.30 gears. And I know it had 17" rims, IDK what tire size though.
Old Jul 17, 2007 | 06:33 PM
  #102  
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ill tell you what i heard today from what i consider to be a credible source-

you all know how dedicated (possibly "obsessed") the rotary engineers are at Mazda- often working on their own time like during the "creation" of the renesis. Well they have apparently again been burning the mid-night oil on the "renesis 1.5/2.0 project" to the point that some of them were quite clearly exhausted. So Mazda has given them all a mandatory vacation for a little while.

this halt on rotary work could be the basis for the rumor ash heard
Old Jul 17, 2007 | 07:02 PM
  #103  
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Rotards forever :D

good post, zoom.
Old Jul 17, 2007 | 07:17 PM
  #104  
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Can a 2.0 L 2-rotor even be efficient with the geometry issues? I thought 0.65L per rotor was settled on because it was the sweet spot for efficiency and power.
Old Jul 17, 2007 | 07:25 PM
  #105  
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Originally Posted by RX8Maine
Can a 2.0 L 2-rotor even be efficient with the geometry issues? I thought 0.65L per rotor was settled on because it was the sweet spot for efficiency and power.
who said 2 rotors?

with todays technology maybe thats not the case anymore, maybe they can go much bigger now

Last edited by rotary crazy; Jul 17, 2007 at 07:46 PM.
Old Jul 17, 2007 | 07:26 PM
  #106  
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Originally Posted by Floyd
Wouldn't a 3 rotor based off of the 12A run ~1.5 to 1.6L? 1.1L / 2 = .55

.55 x 3 = 1.65L

I was thinking 10a rotors
Old Jul 17, 2007 | 07:44 PM
  #107  
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Originally Posted by zoom44
ill tell you what i heard today from what i consider to be a credible source-

you all know how dedicated (possibly "obsessed") the rotary engineers are at Mazda- often working on their own time like during the "creation" of the renesis. Well they have apparently again been burning the mid-night oil on the "renesis 1.5/2.0 project" to the point that some of them were quite clearly exhausted. So Mazda has given them all a mandatory vacation for a little while.

this halt on rotary work could be the basis for the rumor ash heard
I knew one of the big guns would say something

Great news man thanks!

wait! dint they make you sing something?

Last edited by rotary crazy; Jul 17, 2007 at 07:55 PM.
Old Jul 17, 2007 | 10:35 PM
  #108  
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Originally Posted by Raptor2k
Upping the redline won't do anything...the Renesis could redline at 12,000 but it would be pointless because power starts to drop at around 8000 anyway.
...assuming it wasn't retuned.
Old Jul 17, 2007 | 11:54 PM
  #109  
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Originally Posted by DailyDriver2k5
A solid 68HP more than the 8 and lets say the next 7 weighed in a healthy 2800-2950lbs.... GOOD GOD, the next 7 would be a serious contender.
It would be a contender to the cars of today

and we are talking about 3+ years away
Old Jul 18, 2007 | 12:29 AM
  #110  
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Originally Posted by DailyDriver2k5
Mazda stated themselves that 300HP is there base target in the article. If Mazda said that why would they shoot for anything less. Doesn't and wouldn't make sense.

With technology getting better , Mazda could further upon the Renisis motor. Look at the current Renisis now, it makes 232HP in N/A form compared to its FD counterpart that made 255HP with TWIN TURBOS, not one turbo but two!

Thats 23HP more than our N/A rotary, and it used two turbos to get that 255HP goal.

And you guys really think Mazda couldn't give us a base line 300HP rotary? You guys are nuts or either you have a few brain cells that have died.


And as far as fuel econemy, what rotary that you know of gets good gas milage?
Its the nature of the beast......
Remember the target for the reni in full US emissions trim was 250. We all know how that changed in actual production
Old Jul 18, 2007 | 02:17 AM
  #111  
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glad to see mac11 and brillo mentioning direct injection. I honestly dont know all the details of it, but before all these rhumors (true or not) about the next gen rx/rotary engine, I remember people such as rotarygod discussing how DI would be a good way of increasing hp as well as better emissions and that it would be a good solution to some of the common issues people have with the renesis.

If anyone can elaborate on what a decent/normal set up with DI can do (as far as hp improvements or emissions) that would be nice. Nothing too detailed, just something to help show how much DI can do since some people find it hard to believe a 300 hp engine is possible without a turbo.

I havnt really seen much of what ice has said in the past, but from what some of you say he is reliable. But I do trust that zoom44 most likely not post something like that without good reason so for all those doubtful, have a little more faith
Old Jul 18, 2007 | 07:20 AM
  #112  
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Originally Posted by SayNoToPistons
So what if it has two? Doesn't mean it's better than one in every way....
Where in my post did i say that two turbos are better than one? My point is that it took two turbos to achieve that 255HP. Mazda could have used one turbo to get that HP as well.Hell they could have used 4 turbos for that matter.... So whats your point?

My point on the matter is that Mazda built a new rotary that was shy of 23 Hp of a rotary that used FI. Nothing more nothing less. Just like Nissan built a VQ3.5 to attain 300 HP N/A without using twin turbos as the old Z32. Thats call improvement in technology, nothing more nothing less.


Originally Posted by SayNoToPistons
Yeah Mazda listening to their fans. What do "fans" usually want? How many rotary fans are there? How many will actually end up buying a new 30k+ car? Yeah... Doesn't work out very well. Not trying to beat on you or anything, but your posts don't work out too well.

How many people will buy a 30k+ car? Why don't you look at the sales figures of the RX-8 and compare them to previous sale figures of rotary cars of old. I know that awnser, but you need to look it up.

If Mazda built a new RX-7 next year, there would be plenty of people, new intrested ones and old vets alike who love rotaries that would buy one. No, the new rotary RX-7 will not sell like a Mazda 3 or 6, but it was never intended too, its a niche car, like most other sports cars on this planet.
Old Jul 18, 2007 | 07:28 AM
  #113  
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Originally Posted by DailyDriver2k5
Where in my post did i say that two turbos are better than one? My point is that it took two turbos to achieve that 255HP. Mazda could have used one turbo to get that HP as well.Hell they could have used 4 turbos for that matter.... So whats your point?

My point on the matter is that Mazda built a new rotary that was shy of 23 Hp of a rotary that used FI. Nothing more nothing less. Just like Nissan built a VQ3.5 to attain 300 HP N/A without using twin turbos as the old Z32. Thats call improvement in technology, nothing more nothing less.





How many people will buy a 30k+ car? Why don't you look at the sales figures of the RX-8 and compare them to previous sale figures of rotary cars of old. I know that awnser, but you need to look it up.

If Mazda built a new RX-7 next year, there would be plenty of people, new intrested ones and old vets alike who love rotaries that would buy one. No, the new rotary RX-7 will not sell like a Mazda 3 or 6, but it was never intended too, its a niche car, like most other sports cars on this planet.
His point is that it didn't take 2 turbos to achieve 255 horsepower in the FD. You could do it easily with 1 and actually achieve a lot more horsepower. The FD had 2 turbos to decrease turbo lag. The turbos were piped up sequentially, not parallel, with a small turbo spooling first and then a large turbo spooling later.
Old Jul 18, 2007 | 07:39 AM
  #114  
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Originally Posted by Ajax
His point is that it didn't take 2 turbos to achieve 255 horsepower in the FD. You could do it easily with 1 and actually achieve a lot more horsepower. The FD had 2 turbos to decrease turbo lag. The turbos were piped up sequentially, not parallel, with a small turbo spooling first and then a large turbo spooling later.
I understand that, i use to own a Z32TT.
Old Jul 18, 2007 | 08:02 AM
  #115  
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Originally Posted by faboo
It would be a contender to the cars of today

and we are talking about 3+ years away
not really, most new cars even with a power jump will have almost the same performance of today because of the weight increasse

A 2700 lbs car and 280+hp will be a contender in 5 years without a problem, a rx-8 with 300lbs less and todays renesis would be a contender today
Old Jul 18, 2007 | 08:11 AM
  #116  
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Originally Posted by SLWASFK
You're forgetting that the Spirit R Type A weighed in at a touch under 2700lbs.

factor in driver = 2900lbs

I believe it also had 4.30 gears. And I know it had 17" rims, IDK what tire size though.

I've seen nothing that said the final drive was different. but you can go play around with that calculator all you want. changing the final drive size doesn't change the E.T. or the trap speed just the RPM at which those are achieved.

And that is deff. a bhp not whp rated calculator.
Old Jul 18, 2007 | 08:15 AM
  #117  
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Originally Posted by mac11
I've seen nothing that said the final drive was different. but you can go play around with that calculator all you want. changing the final drive size doesn't change the E.T. or the trap speed just the RPM at which those are achieved
Let me see if I understand this. You're saying changing gear ratios can't increase speed?
Old Jul 18, 2007 | 08:20 AM
  #118  
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Originally Posted by 8 Maniac

If anyone can elaborate on what a decent/normal set up with DI can do (as far as hp improvements or emissions) that would be nice. Nothing too detailed, just something to help show how much DI can do since some people find it hard to believe a 300 hp engine is possible without a turbo.
I believe somewhere Mazda came right out and said DI was going to be the next step for the rotary.

From what I have read you can see upwards of a 10% increase in power on direct injection alone.


I'm making some very broad generalizations here so lets not get all ******* but heres what I have been looking at.

current reneiss = (230bhp/1.3)/10 ~= 17.69hp/.1L
next renesis(1.5L) 17.69 * 15 = 265.35hp
add DI - 265.35 * 1.1 = 291.88.
Old Jul 18, 2007 | 08:22 AM
  #119  
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Originally Posted by mysql101
Let me see if I understand this. You're saying changing gear ratios can't increase speed?
What I said was go look at that calculator and put in all the final drive ratios you want it won't change the outcome of the calculator.

http://rx7.com/accel_calculator.html

Last edited by mac11; Jul 18, 2007 at 08:24 AM.
Old Jul 18, 2007 | 08:27 AM
  #120  
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Originally Posted by mac11
I believe somewhere Mazda came right out and said DI was going to be the next step for the rotary.

From what I have read you can see upwards of a 10% increase in power on direct injection alone.


I'm making some very broad generalizations here so lets not get all ******* but heres what I have been looking at.

current reneiss = (230bhp/1.3)/10 ~= 17.69hp/.1L
next renesis(1.5L) 17.69 * 15 = 265.35hp
add DI - 265.35 * 1.1 = 291.88.
I think those # are about right, now put that engine in a 2700lbs kabura
Old Jul 18, 2007 | 08:29 AM
  #121  
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Originally Posted by rotary crazy
I think those # are about right, now put that engine in a 2700lbs kabura
yea....exactly. call it whatever you want at that point, it will haul *** regardless.
Old Jul 18, 2007 | 08:36 AM
  #122  
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I just name the kabura so that people have a clear idea, but im sure mazda will give it a diferent name
Old Jul 18, 2007 | 08:38 AM
  #123  
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Hey ZOOM any info on the engines? hp? DI? anything you can tell us without getting in trouble?
Old Jul 18, 2007 | 10:20 AM
  #124  
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Or how about just some "general" information about the possible benifits if these make it into the next gen rotary engine?
Old Jul 18, 2007 | 10:31 AM
  #125  
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I dont get it, if a 1.5l rotary can be a sustantial improvement over the renesis why are they testin a 2.0l? what car would this engine be put in? how powerfull would a 2.0l DI rotary engine be?

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