For those of you that have ported your engine I have a ?
 

OK, I'm in the process of collecting all the wonderful tools I will need in the rebuild of my 12a. I will be give my engine a street port while I have it in pieces. My question is, how hard it the actual material. My porting equipment will consist of my dremel with the Flex shaft and carbide tips/grinding stones. Is the aluminum of the template the same consistancy?

Anyone have the 54mm or 2 1/8 socket they want to part with for less the sears? :)

Thanks,
Sean

no the housing is iron
much denser

I rented a 2 1/8"ocket for $4.

Don't go to sears, go to autozone or somewhere with really cheap tools, I overpaid for mine but it's an impact socket, but that dosen't really matter now b/c i welded to a 3ft peice of steel channel.
You can probably order one cheap from harbor freight.

Well, Harbor freight was a dead end and auto zone only went up to 2 inches and advanced auto wasnt even in the ball park.

Think the Carbide bits will be able to take on the Iron housings?

yep, do it properly and carbide will take on anything short of a diamond.. why you may ask? because it is the second hardest thing to a diamond :) good luck

thanks

Use a die grinder, air powered. That dremel will take you forever ! ! ! It wont be a smooth either.

The dremel wont be a smooth as the die grinder. Just wanted to make that clear.

I know of and have seen a number of fairly good port jobs done with a dremmel. BDC for instance does all his ports with a dremmel. It does take a lot longer, but you can get good results.

I got my 2 1/8" socket from NAPA, but I paid way too much :(

Dremel worked for me - did take a long time though and quite a few bits, as was said before. While you are in there you should etch the coolant passages in the rotor housings for increased cooling capacity of the engine. For the fywheel socket, go to just about any decent autoparts store and ask for a 2 1\8 socket for ford 4x4 hubs - will be way cheaper than just about anything else (although the $4 rental is probably still the best deal if you can find it).

crap, if sears have one in stock buy it , use it, return it. i'm just a cheap scape. all my clothes still have the tags on.

Please go into further detail on this one. First time I have heard of it. Tried a search but no luck.

Sean

I did my irons in under an hour with a sanding drum and a Dremel. Metal-eating bits worked *slightly* faster, but they were generally smaller and that made it real hard to work with... for example trying to turn a flat edge into a nice contour, with the faster-cutting, smaller-diameter bits it is SO easy to end up with a series of troughs instead of a nice multidimensional curve.

The irons cut easy. The aluminum rotor housings are a bitch, though. Doesn't make sense to me either, you'd think the softer metal would get eaten faster. I used a NARSTY looking carbide bit and an air powered tool, it still took about two hours though!

Somewhat OK pics of my porting can be seen at http://my7.rx-7.org/PJ and you can't tell from the pics but I didn't touch the runners, they are kinda too big already and they already have a nice surface texture (just rough enough without looking like it was cast with gravel instead of casting sand) so I concentrated on getting the port timing and port exit shape/angle the way I wanted. Worked nicely IMO.

Mazdatrix sells a wrench for removing the flywheel nut, they also sell a gear stop to keep the fly wheel from moving. I bought those, haven't gotton around to using them yet, but they seem to be of good quality. Not a whole lot of money either compared to a "real" wrench.

DONT EVER BUY CHEAP TOOLS!!!! Youll regret it. I only buy Snap-On or Craftsman. Cheap korean tools blow ass.

There is an ongoing thread in the General Automotive section about tools.

IMO Craftsman is garbage if you're a professional. For weekend-wrenching useage like 90% of the people out there, they work OK. I have a Craftsman socket and 3/4" breaker bar for the flywheel nut, it works OK, although I did bend the breaker bar on the last engine I tore down.

If I was building engines as a full time job, though, I would definitely hit up the Matco or Cornwell dealer.

Snap-on is OK but you are paying for the fancy name ... I find that Facom tools are very good and are usualy a good bit cheaper than snap-on stuff.

My advice would be to buy a good ratchet and a cheaper set of sockets ... you will find out what you wear out and break and replace it with the better quality stuff.

A good set of strong impact sockets is a good buy too ... somthing you can stick a breaker bar + "cheater" bar on and not worry too much about breaking them.

I find that Koken make very good sockets too

Mike

Any impact 2&1/8 socket will work just as good and last just as long.

I own a Automotive Repair shop and my socket came from NAPA and it works fine.

The air powered grinder is the way to go for the porting.

If you do not want to buy that socket you can hit the nut with a Air Hammer/chisel combo. It make a little mark on the nut but it comes right off!

Oh yeah,

How tight sould that flywheel nut be?

spec is like 350 ft/lbs, somewhere around there

Sean wrote:

quote:
--------------------------------------------------------------------------------
Originally posted by 1ltr8etr
While you are in there you should etch the coolant passages in the rotor housings for increased cooling capacity of the engine.
--------------------------------------------------------------------------------



Please go into further detail on this one. First time I have heard of it. Tried a search but no luck.

Sean

This is in the Racing Beat manual, and I think it is mentioned as a technical tip in the Mazda competition manual as well. Basically, it involves cutting three or four rows of grooves on each side (ie front and back) of the coolant passages of the rotor housings, on the spark plug side - increases surface area of the coolant passages at the hottest points in the housings, allowing more heat transfer from the housing to the coolant and less stress on the housings and seals, etc. as a result. Very easy to do - after the effort of porting the intakes and exhaust with a dremel this will seem like a piece of cake.

Oh, one more thing - especially while doing the exhaust ports in the rotor housings and any clean-up you might do elsewhere with the dremel, be sure to wear a dust mask - there will be mucho aluminium dust and other stuff flying around.

What about putting the nut back on?
That's a shitty way of doing it, I've got a couple motors people have done that to. One I had to grind down to get the socket on it.

1ltr8etr-- Guess I will have to buy that book:) Next time I order some stuff.

Well, on the search for the 2 1/8 socket. I just logged onto sears.com and ordered it and a 1/2~3/4 adapter for store pick up. Should be at my local Sears in 3 to 5 days with no shipping fee.

For the those that need to re-torque that baby I plan on getting a 24 inch breaker bar and stepping on it without bouncing. If I step on the bar at the 18 inch mark with my 200 lbs ass should put me right in the torque specs for the nut.