^^ the lag of big diesel turbos is fixed with a quick spurt of nitrous. haha.
the best part about diesel torque is that it wont let you go. there seems to be NO peak to its power band unlike every other car ive ever been in. this high reving little car will be a different but super fun feeling im sure!!

looks like unless i can find a small top mount starter ill mod the current bell housing and put the starter on the passenger side.

also after much thought, i have decided to forgo the blower and just stay NA with a 500cfm carb and a basic fabbed intake.
its becoming too tight a space, building a super tight manifold, risk of breaking stuff i dont want to break, over stressing my 1929 ford diff (that are used to seeing 40hp/80tq), and on and on.
and in reality, even with its street port and lets assume 150hp to the wheels... thats still a 12 second flat car if it weighs in at the 1350Lbs (with me in it) that im shooting for.
at least this way i can drive it and not always worry about going lean with the stupid carb/blower set up, and i can use all the power it makes rather than have to baby it around like i do with the diesel car that is trying to kill you the second you start it.
if thats not enough after awhile, ill tear into it do it right and port the hell out of it till it barely idles.

on another note.... is it common for coolent to leak from between the housings? not sure if mine leaks as it hasnt ran yet, but is it a common issue?
while cleaning up the 'block' i cant seem to help but notice small 'stains' around the joining of the 'plates' like what you would expect dried/boiled off coolant to look like.
ill have to get it running first to see, but it has me a bit worried that ill have to tear it down right after getting it going.
does anyone sell a gasket/seal kit to rebuild just the basic "block" and apex seals and the bits id need for the internals? obviously a "full rebuild" kit would be a waste as the engine is so bare the way im going to run it.
??

sorry, long post.

 

lol if you think diesels don't have a power peak, you're in for a mind altering experience.

it isn't common for the external water seals to leak, it used to be fairly common for the dowel pin o rings to leak oil though. Mazda sells an o ring set, and it comes with the water seals/o rings you need to put an engine back together. for some reason it doesn't include the front and rear main seals, so you need to buy those. everything else is sold separately, if you see a kit, its something that vendor has put together, as Mazda doesn't do kits.

imo, its not a bad idea to pull it apart and reseal the engine, worst thing is to put a used engine in and have it use water or burn oil or something. it does add to the rebuild time, but i'd also measure all the seals and stuff, and just replace anything bad.

 

^ cool, thanks
my thoughts were to get it running and driving and then see if it does have leaks. its in such an open frame and so easy to pull that whether i do it now or later wont make a difference as far as removal and tear down time. so ill try my luck. who know, it might be all good.

heres a question that im sure has been asked a million times but a 13b with a street port and a 500cfm carb.... thoughts on power to the rear wheels?

 

depends on a few things, but just a stock engine with bolt on stuff should do 170-180hp. the rest of the picture, is that it will make about the same torque (120ish) from 3-6k rpm*, so powerband is very linear and much much wider than the average piston engine.


*just a ballpark, my friend had a bridgeport engine and it made 130lbsft from ~2500rpm to 9600rpm, which is where the dyno stops reading

 

^ wow, thats weak on torque from what im used to. haha. good thing this car is light, has tall tires, and a 4.10 rear end. haha!
when you say "bolt on stuff" what are you referring to?
obviously ill have open exhaust, its got a moderate port done, and im sure the 500cfm carb wont be as good as fuel injection would have been so i was thinking 170hp tops?? maybe 150hp at the wheels if im lucky? (now that ive decided to stay NA)

also, because some will think its cool.... i did this the other night along with setting up the conventional braking system. i cant wait to eat up tires sliding around corners!



or, you know.... this...

 

wow, this build is too cool! i'm subscribing to get updates.

 

haven't done any more engine work lately but i did finish up the rear end and made a conversion from the old ford 'torque tube' drive line to the RX7 drive shaft on my lathe. cost me $19, and $100 to have my drive shaft cut down and balanced. should have it back on Monday.
next i need to pull the trany off and put the clutch in it (i didn't put it in while mocking up motor/trany mounts), and then figure a way to mod the bell-housing and relocate the starter. ive played with the idea of using the top mount starter from the RX2/3 but cant seem to get enough solid answers on if it would work with my 86 turbo trany and flywheel. most things i read point to no, so ill relocate this current one to the top... some how.

 

ok i have a flywheel question...
my engine is an 86 N/A 13b. the trany i have is (i believe an 86) TURBO 5 speed. from what i can see, and have tried, the tranys splines are different than the NA clutch/flywheel and wont allow it to seat up to the block with the N/A clutch.
so i need to use the larger (225mm) diameter flywheel/clutch that matches the turbo trany in order for it to bolt up.
now, i read about differences in counterweights, and rotor weights and so on. so, assuming my turbo flywheel/clutch is the same year/gen as my motor (86), it sounds like it is safe to bolt on without blowing out my E-shaft bearings within the first few miles of driving??

both the N/A flywheel and the turbo flywheel LOOK the same, other than the turbo one is the larger diameter (225mm) rather than the smaller 205mm N/A one. are there numbers on the back that i can look for to be sure of what i have as far as the turbo flywheel is and if it mates up safely?

ive been reading but want to be totally sure im not wrong. insight please =)

 

yep. the counterweights are needed to balance the rotors, similar to a piston engine. as part of improving the rotary, Mazda has lightened the rotors at each engine revision. so the 68-85 13B rotors are like 12.5lbs each, the 86-88 rotors are about 10lbs, the 89-2003 rotors are about 9.5, and the Rx8 is something like 9.3.

Mazda engineered its own transmissions and diffs, and they have a hp/lbs range they are used in, so the NA FC is at the upper limit, of its 225mm clutch/M type trans/M type diff. the turbo then got a bigger clutch, 240mm, the R box, and the P type diff.

the S4 NA flywheel will have an N326 cast on the back, and the turbo is N318/N319

the N350/N370 is the later S5, the N3A1 is the FD, and N3H1 is Rx8. the earlier flywheels usually don't have anything cast into them, if you're lucky its got a stamp or something.

as an aside, the S2000 uses the M type diff @240hp and they are "made of glass" whilst the Rx8 at 230hp uses the P type and "doesn't have enough power to break anything"

 

^ ok, so i went and looked and the small NA flywheel i have has 326 cast into it, while my bigger turbo flywheel has 318 cast into it.... so it looks like im going to be ok to hybrid the 2 together. ??
looks like they are both S4 parts.

 

yep!

 

sweet beans!!!!

 

got the clutch in tonight and pulled the bell-housing off and am now working on fabbing in the starter on the passenger side so its out of my pedal area.
looks like it should turn out good. i just took the measurements from the stock location and am cutting and hacking to get the same center measurements on the other side. still need to make a mounting plate and weld that all in but so far, the measurements are dead on and my cut out is nice and tight to fit the starter so i shouldn't need a shield over it.

stock is 5 7/16" from starter teeth, to the outer edge of the throw-out-bearing sleeve...

 

another question..... the 2 vacuum diaphragms on a 85 distributor, do they both just simply go to a manifold vacuum?

im hoping to get this rig started up in the next day or 2.

 

You can leave them open.

 

^ vac advance is not required?? explain.

 

Your Edelbrock has two nipples. Choose the one that is timed. I don't recall which is which. Then you can have your vac advance.

 

turbo-minivan ^ vac advance is not required?? explain.

Vacuum advance will just help the engine rev up more peppy from low rpms.

To simplify the system for less chance of failure, racers just lock the timing at the distributor for optimal timing at full load in the power-band with no vacuum advance or centrifugal retard.

 

But on a car that will be driven on the street, a fully locked dizzy isn't a good idea and I never recommend it.

Heck I have a blow-through turbo setup and I use a semi-locked dizzy or "limited advance" of only 10 to 12 degrees. I get 0 degrees at idle for easy starts. Then it only advances to about 10 at higher RPM and works perfectly for me.

Works FAR better than fully locked, even with boost!

I can't imagine fully locked with NA.

I've never heard of or seen a failed mechanical advance on a healthy dizzy regardless of its use. I've seen stiff ones, from sitting with rust or hardened grease.

If it is stiff, it must be serviced ie greased and functioning mech advance weights etc. But don't lock it. That's just amateur.

 

thanks guys. ill probably just run them normal.