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Nah, it's a completely custom car.

Carnage - what I meant was, other than what is written in a thread on a forum, did you look into it after wards to confirm. That guy only believes IIRC. I'll look into it tonight.

Brian - The apex seals are the equivalent to a head gasket. When one goes, you lose compression and the motor is "blown". It's just that if you can't do it yourself, finding someone to rebuild an engine is complicated. When mine blows, I'll be rebuilding it myself. If it fails, then I'll send it out to a shop and get a bridge port done at the same time. :)
Actually, the Apex seals are more like piston rings and valve seals as coolant doesn't pass them. They maintain compression though, so your right there.

Engine rebuilding around Ontario is not hard. Scarborough Mazda and Dave Wood both have Master rotary mechanics on site and build quite a few racecar motors a year. Besides that, there are plenty more worth mention. Just thought I'd add that in.
 

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Did you guys see that 87 RX7 on Passtime last night. Blew the motor or the tranny on the line! ahaha... He was bouncing it off the rev limiter and it jerked and jusy stopped dead.

Hey joey... could you post a video of your buddy's 20b?
Nah, didn't see that. Link???

As for Andrews 20B, I don't have a video of it running, and I don't think he's up for taking it out of storage just for that. I believe I have a pic of his engine though. Here it is:




^ That thing is as big as my face. :eek:


Actually, the Apex seals are more like piston rings and valve seals as coolant doesn't pass them. They maintain compression though, so your right there.
I guess you're right as well. It's kinda hard to really say because the engines are so different. It kinda acts as both :p You know, those 3 parts all together do the same job as the 40+ in a piston engine.. :lol:

Engine rebuilding around Ontario is not hard. Scarborough Mazda and Dave Wood both have Master rotary mechanics on site and build quite a few racecar motors a year. Besides that, there are plenty more worth mention. Just thought I'd add that in.
This is interesting. If I end up needing a shop rebuild, and I'm still in eastern Canada, I may just drive it out there. :tup:

How about this? Make a list of all the shops that rebuild engines other than Mazda dealerships? (Which I don't recommend unless they've been around since the early 90's and actually SOLD RX-7's, as well as a mechanic that was there then) Could be helpful info for those who are looking into getting one but are worried about how to go about a blown engine(most Rotary owners go through a rebuild).

Also, if anyone wants to attempt a rebuild, the parts can be purchased here: Atkins Rotary
 

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long time rotorhead (got 1st rx7 in 1991) dont have one right now but some pics of the last few-
87 n/a gxl (86k org miles DD)




7stock

old 86 n/a




my 1st 7 with built 12a


drag racing FD in '03


dirt track 1st gen
 

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kiesel used to have a sick FD rx7


7PARTS.com - Specializing in aftermarket parts for the Mazda RX-7

He sold it to a fellow in south america who is racing it in a local series there.

The bugeye is the 2nd variant of that car. Originally it was a 400-450-ish HP 3 rotor 20B with an extremely trick slide valve throttle body. For the region he runs in it was simply too loud for the sound regs they have there(shrieked like a banshee!!). After multiple massive mufflers (3 of the same size as whats in the picture) it was found that the induction noise was almost as loud. Even shrouding the intake didnt help so he replaced the engine with the world most powerful muffler :)

Gavin
 

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I have always liked the look of the RX7 with the lights down, when the lights are up, i find it kinda fugly. But i'd still own one.

What worries me about rotary is APEX seals!
Dont let it worry you!
In the early Rx days up to the Rx5 the twin dissy motors all used 6mm carbon apex seals, which were notorious for problems...they switched to 3mm steel seals in the late 70s, and then to 2mm seals in the FC.

I have heard of people going on to rack up 300,000km in an NA FC.

Most engine builders usually replace 2mm seals with 3mm ones if big power is needed. 6mm seals had an upside, they would allow quite high rpms...there used to be a club car series for 2.0l and under, of which the 10A Rx3 qualified based on the then 2x displacement rule....those guys used to frequently take the 10A with 6mm carbon apex seals well over 10,000rpm
I dont know how many meetings they were going between rebuilds.

Rotary engines were always popular over here as you could fit one into anything....and people have converted just about every car....VW beetles, combi's minis, ford escorts (british RWD design from the 70s, not the mazda based one) datsun 1200s
here back in the late 80s early 90s you could pick up a used rotary from japan for less than 500$, the most popular engine for conversions back then was the 12A turbo from the 80s japanese cosmo (HB 929 equiv) I remember ther were companies that specialised in drive in-drive out conversions
 

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Well, i guess its all about how you drive your car. My bro had a RX7 with a turbo 2 motor, and many upgrades and in no time his seals went.. But when i think about it, i know my bro would have been driving it hard.. But when i looked into them, i saw that apex seals have been issues in many cases.. so i figured it was a problem that is common.
 

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The issue is that people who are afraid to blow their motors tend to blow them because they try to baby them too much. I drive the shit out of my car, so does my buddy Dom and he JUST blew his motor after 3 years of tracking it and driving it like a madman. I haven't had a single issue yet. These engines NEED to work hard and be beaten.
 

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Well, i guess its all about how you drive your car. My bro had a RX7 with a turbo 2 motor, and many upgrades and in no time his seals went.. But when i think about it, i know my bro would have been driving it hard.. But when i looked into them, i saw that apex seals have been issues in many cases.. so i figured it was a problem that is common.
One issue with the rotary that most people neglect is the need to tune it , just adding an exhaust and intake can make such a drastic difference in the volume of air a rotory can injest that a good re-tune is manditory.

With our motors (KL's FS's F2's etc) we can do similar mods with no tuning and simply live with less than ideal numbers, with a rotary such mods can lead to a lean condition which adds to the motors already significant heat output and makes detonation more likely. Both issues are leading causes of rotar-death.
 

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Discussion Starter #34
I was out last night with my wife and I never see decent imports in my town. Well I stepped out of the movie theater at almost midnight and I hear a deep toned growl coming down the street and it's a charcoal colored FD, lisence plate was from out of town but read R1 FD. It had some Super Advans on it in black and looked wicked. did a rolling burnout half the block in front of the cop shop. LOL classic!
It's strange to see something that nice in Iowa. Usually its all trucks or a muscle cars.
 

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Here's something else that we don't normally talk about when it comes to the RX-7. The car is a freaking chick magnet! I went out last night and got 3 numbers, a date for Friday and Dominique(yes that''s a woman's name) Just went home!!!!!!! :lol:HAHAHA, just thought I'd share. If anyone needs a date, an FD will help! XD
 

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All this discussion about rotary reliability has forced me to chime in again. Rotary engines see maximum efficiency at roughly 5,000rpm. That's the point a which you get optimal performance and fuel economy. It's also around this point that seals wear less. That's why rotary engines that are used are better then ones driven by people without a clue.

So, why does the engine last longer at higher rpm? Because the rotors tumble. The actual speed at which a rotor moves is roughly 1/3 the engines actual rpm. At low rpm, the rotors wabble, forcing excessive wear on the seals. At high rpm they go into more of a spin motion as the outward forces acting on them force them against the walls of the rotor housing more consistantly like a piston ring would be.

Hope that helps to clarify. It's one thing to say that the do last longer when driven hard versus actually knowing why.
 

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I'm not surprised mike! Both you and I are sold to doing the same thing with cars! haha. All go, in curves...no show.. :p

All this discussion about rotary reliability has forced me to chime in again. Rotary engines see maximum efficiency at roughly 5,000rpm. That's the point a which you get optimal performance and fuel economy. It's also around this point that seals wear less. That's why rotary engines that are used are better then ones driven by people without a clue.

So, why does the engine last longer at higher rpm? Because the rotors tumble. The actual speed at which a rotor moves is roughly 1/3 the engines actual rpm. At low rpm, the rotors wobble, forcing excessive wear on the seals. At high rpm they go into more of a spin motion as the outward forces acting on them force them against the walls of the rotor housing more consistently like a piston ring would be.

Hope that helps to clarify. It's one thing to say that the do last longer when driven hard versus actually knowing why.
I knew the gist of it, Never knew the "why" on the apex seals running more smoothly though! Thanks for that info!!!!!!
 

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Discussion Starter #39
Damn, thats kind of funny. It's like the perfect engine for performance applications then. Since you are high revvin' it anyway, it actually is more efficient and lasts longer. So then does the 'wobble' causing wear on the rotors at low RPMs turn into full centrifical spin the higher you rev? Similar to the big slicks on top fuelers during the burnout. They friggin grow when they smoke those pups!
 

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^Pretty much. Don't worry, I'm not trying to come into this thread to prove wrong, just adding to the discussion. Good thread guys!

This is particularly why Mazda recalled almost all engines on the RX8 a few years back. The 6th gear in the RX8 doesn't let it rev high enough to get the rotors to spin properly. So the motors wore away too quick. Mazda would have lost either way though. Either make the engine rev too high and get complaints from people not used to it and therefore loose sales and brand image or gear them like North American's expect, blow engines, and loose brand respect for the rotary. Think many dealer sales staff told consumers to beat the snot out of their RX model cars to get the longest life and best fuel mileage? Doubtful.

EDIT. Just to add. This is the EXACT reason why the 787B LeMans car was no longer allowed in racing events. Better longevity and mileage then all other cars on the course. Less time in the pits meant more wins. That's only part of it I'm sure, but makes you wonder why they didn't disqualify the new Audi TDI LeMans cars for the same reasons....
 
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