i picked up this atkins rebuild from the junkyard! i tore it apart, and everything seems to be fine. how do these ports look? should i get a template from mazdatrix to go bigger? or should port a little more on my own? what do you guys think?

 

How much did you pay??? Also, How do you know its an Atkins rebuild??

 

Those look pretty good. The Mazdatrix template is slightly smaller.

You can to larger on the secondaries, but leave the primaries alone.

Really, I would leave those in tact if I was reassembling the engine. They're already quite nice.

 

that must be nice to find those at a junk yard

 

Damn wayland you got lucky!

 

Damn, those ports look exactly like the ports I did on my '88 GTU. Also I did an atkin's rebuild kit with it.... tell me, were the trailing spark-plug holes drilled-out to the same size as the leading (little experiment I did)?

 

I paid 113 bucks! I knew it was an atkins rebuild cuz of the serial numbers followed by an "ARS" stamped next the the mazda logo. Also there was a sticker on the 19mm E-shaft bolt"void warranty if removed". And no the trailing plug holes were not drilled out.car I took it out of had 190k I'm thinking engine has about 20k if that. it was pretty clean when i took it out. here are some more pics. And YES it was AWESOME to find this engine, I was and still am stoked!........thanks for your guys's opinions! Lucky? or skillllz!!
btw...I havent even givin them a bath yet. just wiped em down.

also i'd like to know how much hp you got out of your similar ported motor black sunshine?

 

sweet find man

 

Maybe atkins can look up the serial number and give you some past information on the build? I spose thats against policy though, release of customer information..

 

I thought about that, but I don't want to waste their time. it really makes no difference. here are some compression reading atkins did before it was shipped out.

 

nice thouse housings loow awsome for a build

 

Interesting, they left the exhaust difusers in.
Most of the porting threads I've read says to grind them out, anyone have any info on that?

 

Most places will either use turbo housings or leave the diffusers in on a 6-port engine b/c they're too hard and not very easy to grind out. There is a FAQ on Mazdatrix's website that covers it.

 

I wonder how that FC ended up there with the engine still in it.

They had an Atkins rebuild, so they must've known it was worth something when they had it done (probably cost them a pretty penny for the port job and everything), but yet they let it get scrapped.

Or maybe it got impounded and they never picked it up as well, lol.

 

The exhaust diffusers really don't kill flow that badly, but if you remove them, you significantly increase the exhaust noise.

 

ya... I know some people grind out the exhaust diffusers, but i also know some people say to leave them in. ahhhh....I can't make up my mind.