rbeecro

just picked up an 87 rx7 (appears to be in pretty good shape) for 500 bucks, but engine would not turn over so removed starter and used a bar to pry on the flywheel teeth.

The engine slowly began to turn. it now turns 1/2 turn either way and comes to an abrupt stop with a metalic sounding clunk.

So now the questions are.....

how hard is it to rebuild a 13b engine?

what is the cost of a rebuild kit

where to find one and who would have it....

the guy who sold me the car said he would refund me the 500 if it turned out to be that the engine was shot.

i have heard of the j-spec engines for 1k and would it be worth it to me to keep this and just transfer all the electronics over to the jspec?




thanks in advance
bob

CrackHeadMel

iTrader: (2)

what model is it? T2? n/a?

if its a t2 i say rebuild it, if the car is realy in as good of shape as you say it is

i can turn over my engine by hand by grabbing the pullys up front, not hard at all

dr0x

I would get a jspec, test all electronics on both motors. Which ever parts were closer to factory spec are the ones I would use. The factory service manual has a billion procedures for testing stuff. Some stuff youd have to use off the old motor, and remove some stuff from the jspec. But that seems like the easiest and cheapest solution IMO.

rbeecro

sorry about that... it is a 13b fuel injected and no turbo.

i'm not to use to this type car so i'm not quite up to the lingo that goes with it.

bob

HAILERS

1000 bucks for a self rebuild, give or take a couple of hundred. Add a bunch more if you need to replace a rotor housing or side housing. See Mazdatrix.com for prices of things.

500 bucks for the car sounds not out of bounds. Even with a broken engine, if the rest of the car is pretty good.

rbeecro

actually i got the car just for the engine.....

i'm gonna try to put it in a sandrail using kennedy engineering kit....

hmmm maybe i should just get a j-spec and work that way..... i'll have to check with mazda trix

b

HeffBoost

Cool. What kind of chassis? Mid or Rear engine? I built a standard VW one when I was in high school. A rotary would be OK, but you're gonna be short on torque. Turbo rotary would help. Corvair flat-6? There's all kinds of cool powerplants for rails. Fun stuff.

rbeecro

home made chassie class 5 race and rear engine mount....

i'm gonna use a bus tranny w/ 5.86 r&p to make up for the low torque at the bottom end until 3k rpm's....

already talked to a guy who's done this on other rotary powered rails....

i'm running 960 lbs... not counting my weight... but if i can keep gears 1st & 2nd close and tall enough then i can stay in the power band around 3k in 1st and run up to about 5.5 to 6 k. The bhp should work....

many people have warned me about the low end torque problem but i feel that i can overcome this with the proper tranny and gearing..... !!!! I hope!!!!

but i've got this problem with the engine and i may have to do the j-spec thing..... I just found mazdaracing.com and they have j-spec's for 1k$$$$

when u got a buggy.... 1/2 the fun is trying to add power to it in different ways..... and these rotary engines are very unique and outstanding motors.

i just need more info on them.... i've got the time.... i just need the info on how they work.... i've seen them in other rails and they are turbo'd....

i'm currently running a mild type 4 porsche engine and about 135 bhp... that's enough to kill yourself with but i'd really like to work with these.....

so i'd really like to port and polish then add a turbo and see what 225bhp would do....

so i'm off to find another rotary power plant.... the trick is to do it with the least amount of $$$$ and the least amount of weight.... and it does seem that the rotary engine could be the answer..... that is with the correct tranny behind it....

bob

HeffBoost

Never mind. You're all over it. I think you've got the right approach with the gearing. Those big tires will offset it somewhat but should work out good. With stock gearing and truck-size tires it's geared up way too much. Ours was really short for the woods and it would get pretty squirrly up in third.

Sounds like a cool idea. Best of luck.

These forums are a good way to learn about rotaries. Lots of info. between all of them.

jacobcartmill

iTrader: (6)

if you put a 13bt (13b turbo) motor in your buggy, you could easily have 240bhp with stock internals and turbo (of course you'd have to add a little fuel and do a little tuning.) then you could put a bigger turbo on it and add some fuel (depending on your setup for the turbo and fuel) and get maybe 3 times what you have in that thing right now with that porsche engine, and it would weigh about the same.

i want to hear more about this project.