Hey guys,
I bought my first rotory about a month ago, an 1985 gsl with a swapped 13b (i believe it is from an rx4) i've tried to snoop on the parts and tuning that was done as much as i could without tearing her down... i've always been a gear head and always loved cars but never knew the love of an engine untill my rx7... by god the way it rips through the ever gaining rpms without effort is pure bliss for a car guy. and the way everyone else seems to slip farther and farther back tends to tell of how quick she is.

i <3 my Mazda. truly made a fan for life.

so far what i've figured out the following:

i have a four barrel Mikuni carb.
i'm not exactly sure about the power plant. i clearly know it is a 13b (i _think_ its from an rx4) I'd like to get more information on the rx4 in its stock form.

I also have reason to believe it has a mild street port (simply guestimating because of the idle and performance.) the tranny (5spd) i _assume_ is a from the same rx4 or perhaps a gsl-se?, any difference?
it has a full racing beat exhaust setup from the header down to the muffler (although its got three presilencers of which i'd like to remove two, suggestions?)
it also has some after market spings and generic struts. (i believe racing beat springs but don't quote me on it)

from maintenance records i found out it used to be an auto 12a
so i assume they'ed of rebuilt the 13b previous to dropping it in but can be sure. it looks to be in pretty good shape and it would appear to be rebuilt because of the paint job on the block.

with the swap though a couple things bother me. oil pressure and temp gauges not hooked up (new cooling system seems to make me not worry much about the temp but she seems to constantly be cool. if i turn the heat on (unless its a VERY hot day) it comes out only luke warm)

I'd also like to keep my eyes on the oil pressure seeing as i do quite enjoy running her with my mates cars (spanked my buddy's wrx which is mildly modified)

anyhow i've tried to keep her under 5500 rpms for regular daily driving (as i'd like her running tip top as long as possible) on the recommendation of a buddy who used to own a mazda shop.

but this morning i went down the block to drop my brother off home and she seemed to be idling very rough (its dark but tomorrow morning i think i'll check for vac leaks) and i can absolutely feel something is wrong. shes louder then before, the engine shakes pretty drastically compaired to previously and while it doesn't feel like there is a power loss (actually when all four barrels open up she seems fine. hrmm well seems like i may have a problem with my carb or fuel delivery don't it?
ah yes i also had my first backfire with her on the return home. *sigh*
the only car i've ever enjoyed this much is my 85 supra (although its a completely different beast)

also i think the first few things i'm going to do to continue is a full suspension rebuild and i've been _thinking_ about a holly carb but my buddy says the mikuni is a solid carb and he doesn't see much a point in changing.

any suggestions or comments welcome. also i just drove her about 400ish miles from southern california to sacramento (moved) and she was _AWESOME_
i'll get pictures of her up when i find my data cable


your latest rx7 nut,

Isaac Acuna.

 

Welcome to the rotary world. Some really knowledgeable people on here. But there are also many who love to make stuff up as they go along. If you have mechanical expertise with pistons you should be able to smell the crap from the truth. Just curious, what makes you think it is an rx4 13b?

 

Not sure if keeping it under 5500 rpm will make it last longer. These cars need a good thrashing from time to time to burn the carbon out of the engine. Redline on a 12A is about 7-7500 rpm, assuming its the same for a 13B.

Driving it like you are going for groceries is what kills these cars.

factory service manual is here http://www.wankel.net/~krwright/cars/rx7/manuals.html

check the faqs and read through some of the stuff. If youve got a question, do a quick search first because alot of the common problems have been covered quite a bit.

To steal (trochoids maybe?) saying welcome to the dark side.

and to quote fireslayer, I pronounce you man and 7, you may now kiss your paychecks good bye

 

Sorry to double post
Not to sure how much you've read on the forum or how much youve done on your car since buying it.

Obviously it is good to do a full tune up such as oil filter(fram is recommended against), fuel filter, thermostat, If there have been oil leaks on any rubber hoses you should consider replacing them etc do a quick search and threads will turn up (i cant remember where they are otherwise id post the link)

on a curiosity just to double check...you have a carberated 13B? thats a rare set up.

 

Hmm.. I never really looked into RX4's so what would the main differences between the 13b from an '85 Seven and an RX4's be? I'd figure it would be carbed if it came from the 4...

 

Welcome to the darkside!

Post pix of your car if you can

 

As for the rough idle. Is it idling rough in about the right range or is it really low? does adjusting the idle setting make a difference? I believe there is a vintage part of the forum as a section both on rx7club and on nopistons

 

Acuna Matata

 

Welcome to the forum...have fun with the rotary PWR!!!

 

Hey why dont you head out to Elk Grove on saturday heres the thread https://www.rx7club.com/west-rx-7-forum-193/sacramento-elk-grove-meet-dec-15th-709112/

and there is also i thred for monthly meets in the Bay Area for Nor Cal chk this out too.
https://www.rx7club.com/west-rx-7-forum-193/nor-cal-rotary-club-707481/

i ll most likely be at both if this new security job doesnt kill me during the working grave.

 

Man, Jeffs posts are always so awesome.

 

welcome! same model as me, except I'm running the standard 12A. This forum is great! The cool thing about rotary is it takes such a great thrashing and asks for more! on a nice day I always redline it at least once, in second and maybe third. The rule of thumb with our cars is drive it nice until it is up to full operating temp and then have a go! If you want a grocery getter, buy a Subaru, or a Toyota. great fun to WOP. now go out there, and God speed!

 

what a wonderful phrase

 

I was going to say what a wonderful welcome.

 

thanks for the warm welcome guys, and i'll be at the sac-meet. i believe it is from an rx4 because i had a conversation with the previous owner and he believed it to be. it is indeed a carb'ed 13b though. as for the idle i'm pretty sure my carb may need adjustment and or may have a leak it seems to be experiencing low rpm issues but as soon as all four barrels are open it has the same power and smooth acceleration.

i haven't had time to get at her yet i suppose before i go to the meet i'll try and tune her and check for vacuum leaks.