i recently blew my 83 rx7 gsl. i was in 1st and got my rpms to about 7000 and when i went to shift my engine blew. i just put a full tank of regular gas in it from a shell station. after i blew it i asked someone who knew allot about these engines what he believed caused it to blow. he told me that it was probably the fact that i didn't use premium gas was probably the cause of it. i plan on rebuilding this engine so i would want to know of any other reasons it would of blown after the engine was rebuilt 50000 miles ago. (the car had been sitting for a while). please leave input, thnx

 

ok, Jarrett...first, run very far away from the person you know who knows "a lot" about these engines because they don't. Your gas didn't kill the engine. Fact is, 87 octane is pure honey for the naturally aspirated 12A rotary engine. If you could find 85 octane, that's even better.

Revving an engine to 7000 rpm when it's old? Yea, that's asking for it. You probably still had the gas down and the engine went past 7800 rpm before the shift when the clutch was out.

Mario III

 

that's BS! i run 87 in mine every day all day.

LOL! beat me to it mar3.

 

Yeah, find better friends....

Revving high like that after it had been sitting "for a while", good chance you had something that was feeling sticky and didn't want to move the way it should. You forced it, and it broke.

 

got it thnx guys, what do you think would have gone on the engine that would need replaced other than the rebuild kit?

 

You'll probably need a housing and a rotor. Finding a rotor should not be an issue, but 12A housings are getting pretty hard to find these days.

 

do u think going with used housings would be the right way to go? im trying to save as much money as posible!

 

what you really need to do is get the cherry picker out. pull the engine out, put it on the engine stand. Then proceed to tear it apart and look at your peices to see what is foobared. (broke) Then all you got left is to order parts and put it back together. That's the way I learned w/ blown engines. (But then again I've blown nothing but piston motors....and a hole in the block from the connecting rod isn't gonna be fixed no matter what.) Sorry getting off topic. But yeah, what I'd do is basically a tear down to examine and build w/ new parts replacing what looks obviously damaged. Good Luck. If you need places to look for parts here are a few places to start.

http://www.RX-7.MazdaPartsCenter.com

http://www.rx7store.net/

http://www.rx7restoration.com/

http://www.blackdragonauto.com/

 

ok thnx those links are very helpfull

 

no prob bro that's why we're here

 

i also forgot to mention that my engine locked up shortly after it blew. i can still rebuild it right?

 

lol of course you can. Just so long as there isn't a hole in the block. You'll have to replace gaskets and all the other sorts that comes with the job of tearing it apart. Just inspect the insides for cracks. You don't want to order new parts and have a crack and have the cooling system ruin your motor and Hydro lock it.

I've locked up 3 motors and fixed 2 of them. (I race too much.) But if you know what you're doing and have faith in yourself and are DEDICATED. You can do this.

All you need is time, cherry picker (to pull the engine), and a engine stand. If you need a link for the tools you're gonna need to buy go to http://www.jegs.com and look for the cherry picker and engine stand. Sometimes you'll even be able to find them at you local auto parts store as to say Advance Auto Parts had a cherry picker for $150 bucks.

But yes you should be able to rebuild it so long as the block is undamaged long story short.

 

It was me that said using 87 instead of 93 didnt help(coming from a turbo rotary owner 6 Fcs and 1 FD and counting). He has a 12a with a racing beat intake with 4bl, header and exhaust, streetport, aftermarket ignition, ect. With what he said during the conditions and the way the car ran it was detonation which could be timing if it was tuned to run premium, or it it was just time and a apex seal just let go. Pretty much told him off the bat once it had the carb i had no clue lol but i know the sound of a blown rotary.

 

what gaskets would i need to drop new engine into the 7?

 

turbo10th, for shame! Yes, what you say is absolutely true for BOOSTED rotaries but not for carbureted rotaries running "low" compression numbers.

Now ya knows!

 

probably need more than just gaskets.

 

well what all do i need to put a new engine in?

 

err...ummm

 

just picked up another 12a tonight gonna try to put the new engine in this weekend

 

I always reseal the oil pan with rtv, front and rear main seals, intake gasket, exhaust gasket looked new but might wanna replace that too. Dunno what else off the top of my head.

 

when i replied i thought u were talking bout a rebuild.