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-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   What do you think of these ports? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/what-do-you-think-these-ports-502086/)

Sideways7 01-22-06 09:27 PM

What do you think of these ports?
 
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So, I just got my engine out (I'm excited if you cant tell). So anyway, what do you think of these port jobs? They were done at Alamo Rotary by Tito.
Also, does anyone have a picture of the stock 6 ports? I can't find one for some reason.

Jager 01-22-06 09:54 PM

For pictures of a stock port go to Kevin Lander's website. He has before and after, I'm sure you could find something to compare t.oo.

Good luck with the build yo

Dr Felix Wankel 01-22-06 10:01 PM

what would you classify that port as?

Sideways7 01-22-06 10:02 PM

Thanks. I don't know why I didn't think about kevin's site.
So It looks like there was a pretty substantial increase in the port size. I could tell from how it drove, as it made good power almost to 7500 (this is an s4, btw)
Unfortunately, I dont have any money at the moment, so I wont start rebuilding it for at least a month or two.
Edit: I think thats classified as an extended port (or a large street port)

Dr Felix Wankel 01-22-06 10:07 PM

dude you drift that thing? do you think youll be ready for this summer?

scathcart 01-23-06 12:49 AM

I'll bite.

As far as I can tell, they open very early.... so early that the leading edge of the side seal will not be supported.
There is also no chamfer on the closing edge of the ports.
It looks like that engine will munch side seals pretty readily.

There's quite a bit of induced overlap from those ports. Drivability will be decreased, and the powerband will be shifted upwards.

What do the exhaust ports look like?

I would put quite a bit more work into the ports.

Grab some pictures of the runners, too.

What did you pay for this?

eriksseven 01-23-06 01:14 AM

Hey, Sideways7, chamfering would be a really good idea. You could do it yourself in about 15 minutes. :)

sossfc3s 01-23-06 02:03 AM

they look clean i just would think they would be more angled at the end. i am sure they did a good job good luck with your rebuild

SureShot 01-23-06 07:15 AM

It looks like your side seal tip may be exposed.

A radius on the closing edge of the port may save it.

http://208.62.166.66:82/guest/pics/9...ut-comment.JPG

Sideways7 01-23-06 09:13 AM

Well, this engine actually has about 25k on it with these ports with no problems (related to the ports, at least.) I pulled it because I thought I popped a seal, but they were actually carbon locked in place. The thread about it is here: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/finally-got-engine-apart-now-i-have-some-questions-about-engine-condition-502068/ Feel free to reply to it as no one has yet. :(

SureShot 01-23-06 09:20 AM

25K - excellent!

The port did look right on the edge - but that's where the fun is..

Sideways7 01-23-06 10:21 AM

Yeah, it definately had overlap on it. There was a slight lope to it, in addition to a huge lope, but that was from a vac leak that I didn't find until I was pulling off the rats nest. As I said, it made good power to over 7k, close to 7500. To my knowledge, there is nothing done to the exhaust ports. I might get new housings and get the exhaust ported a little on them, since most places wont port used housings. Now that I see the condition of the housings, I might keep them, though. I'll have to look them over more closely to see. This isn't my daily driver anymore, so I might go crazy.

SureShot 01-23-06 10:52 AM

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On my housings, I opened the exhaust a little sooner, but left the closing unchanged.
Works good - lasts a long time..

Sideways7 01-23-06 12:54 PM


Originally Posted by SureShot
On my housings, I opened the exhaust a little sooner, but left the closing unchanged.
Works good - lasts a long time..

Wouldn't that increase the overlap even more, though? Or is it not going to matter that much?

Carzy Driver 01-23-06 01:11 PM

overlap happens when you take too much out going upwards towards the intake. rounding the edges won't hurt too bad, may not even notice

Sideways7 01-23-06 01:20 PM


Originally Posted by carzy driver
overlap happens when you take too much out going upwards towards the intake. rounding the edges won't hurt too bad, may not even notice

I was talking about opening the exhaust earlier increasing overlap, not rounding the edges.
Also, I just realized that I have Turbo housings. In fact, I think I might have gotten new housings with my rebuild. The recipt for the rebuild doesn't have a detailed list (it just says Parts and Lubricants) but the price looks like it includes new housings. Maybe I will just use them after all.

Carzy Driver 01-23-06 01:48 PM

opening to exhaust earlier wont increase overlap but will cause you to lose lowend torque for higher rpm performance gains.

Sideways7 01-23-06 03:48 PM

2 Attachment(s)
I went back out and looked at my exhaust ports again, and I don't think they have been ported. I attatched some pics if you are interested.

SureShot 01-25-06 10:58 AM

Those exhaust ports have been enlarged..

Sideways7 01-25-06 08:00 PM

Ok, I wasn't sure. It looked like some had been taken off the bottom of the port, but I couldn't tell for sure. Hopefully I can re-use the housings. That'll save me at least a grand after porting is figured in. Is there anything you can do with the housings like take some super-fine grit sandpaper and smooth it down. Seems like I read that somewhere, but I'm not sure.

Sideways7 01-26-06 08:05 PM

Anyone on using sandpaper?

Sideways7 01-27-06 06:32 PM

no one?


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