Intake gasket differences

Jeff20B · 01-30-2009, 03:52 PM

I'm posting this to add to the knowledge base here. Many of you should find it interesting and worthy of this section.

I hope this works.

I made this picture for a guy on the dumb forum who, for whatever reason, couldn't quite wrap his head around why Mazda had different types of port runners, and gaskets to match, or lack thereof. When he called around asking questions he was given the run around and became even more confused. I made a real attempt to explain, first verbally and then with a picture. You know the old saying: a picture is worth a thousand words. Well apparently not in this case.

So as to not let this great educational picture go to waste, I've posted it here. I think I'm truely done with the other forum. If a picture isn't enough for some folks, it would be rude on my part to persist any further. Not to mention fruitless.

Did anyone here find this picture useful for your next carb or manifold upgrade?

-xlr8planet- · 01-30-2009, 10:31 PM

I do

orion84gsl · 02-03-2009, 10:54 PM

So far I'm still using my 84 12A, so as of yet, no it hasn't been useful. The future however, holds many possibilities.

Kentetsu · 02-04-2009, 09:20 AM

Man, there's quite a bit of variation in those intake ports! Thanks Jeff, your work has not gone to waste.

***Herblenny*** · 02-04-2009, 09:30 AM

COOL! Thanks Jeff!!

Sterling · 02-06-2009, 02:31 PM

That's a great photo, Jeff.
Can I use that on my website?

Jeff20B · 02-06-2009, 05:06 PM

Yeah, sure. But in what context? Are you branching out from strictly carbs to a more inclusive anything to do with intake and/or power adders (ie ignition) format?

Rogue_Wulff · 02-08-2009, 12:50 PM

Great pic Jeff. Just for reference, you should have had the 6P and turbo 13B intake gaskets as well. You may not have those gaskets handy, and if that's the case, then no problem. Just would have been nice to see all the variations lined up together.
I can't help but wonder if the turbo intake gasket is close to the early 13B, as far as port size/spacing.

Jeff20B · 02-09-2009, 12:31 PM

The pic above was only to show off carbed intake manifold gaskets. I felt it was appropriate to post here as the title of this subsection reads Carburetors and Carb Tuning.. All info about old school carb set ups..

Rogue_Wulff · 02-09-2009, 12:41 PM

Yes, but, there are carbed 6ports thanks to aftermarket intakes. I have one of those.
There are also people wanting to use TII engines with 4port carb intakes. I have heard conflicting info about the latter. I don't know if the intake bolts on an early style 4port is the same as the later turbo irons. This would be a case of a pic being worth more than 1000 words.....

Jeff20B · 02-09-2009, 02:09 PM

I made the picture above because I needed to show the differences of stock carbed intake manifold gaskets, and how you can trim material from the short runner style to have tall runners like a reverse runner '76 manifold or some aftermarket manifolds like the Camden SC, some weber manifolds etc, while retaining a seal around the ACV port, which the mid to late '70s gaskets lack. It was never intended to show the differences in relation to EFI on the later engines.

But to answer your question, the T2 and 6 port engines have the same bolt pattern and similar intermediate runner location and height. Mainly the end plates are different. However there is an aftermarket gasket which has tall connected runners on the end plates to work with a T2 and a 6 port. I got it from Atkins. Kind of a universal gasket for 2nd gens and the GSL-SE.

Sorry, no pictures handy, and it's harder than heck to deal with pictures on this forum because it has new software which causes all pics to have a size of -1 and they don't display for me. I'm using an older OS. That's why I made such a big deal out of that picture above, hoping that it would work. I checked it on a newer computer and it does display on a computer with XP.

Sterling · 02-09-2009, 03:02 PM

Quote:

Originally Posted by Jeff20B

Yeah, sure. But in what context? Are you branching out from strictly carbs to a more inclusive anything to do with intake and/or power adders (ie ignition) format?

Well no, Jeff, I'm not. But I am persuing manifold porting, and it will eventually be time to dedicate some pages to manifold flow and such because I like to explain the science behind the product I offer. Just thought it'd be a good resource, that's all.
As for the ignition thing, is there something wrong with dedicating a page on optimizing ignition on a website that's about modified carburetors?

I wondered why you didn't answer my request to do the ignition write-up for my site.

Jeff20B · 02-09-2009, 10:05 PM

I don't think I could do it justice, as my forum time is limited, and I still haven't done an actual ignition upgrade in a 1st gen yet. Plus I don't have access to a running 12A, let alone with a Sterling carb to give first hand info anyway.

I appreciate that you'd ask me first, but I'm really not the best person for the job. Perhaps someone who has a Sterling carb and adjusted their ignition could give it a try? Has Jon (vipernicus) messed with his ignition? He's always good for a few paragraphs in his nice style of subjective first hand experiences.

warwickben · 02-23-2009, 12:24 PM

well if you need a write up for jeffs ignition mod on a first gen i can write one up. the only problem it would be only good for forks with 1980 sa, or one useing the 1980 dizz.

01-30-2009, 10:31 PM	#2
-xlr8planet- RCC Contributor Join Date: Feb 2008 Location: Buenos Aires, Argentina iTrader: (4) Posts: 679 Rep Power: 17	I do __________________ www.rx7club.com.ar RX-7 Forum in Spanish I make custom decals. Yes, you can ask me

02-04-2009, 09:30 AM	#5
*Herblenny* Founder/Administrator/Internet Pitbull :) Join Date: Jan 2008 iTrader: (11) Posts: 644 Rep Power: 10	COOL! Thanks Jeff!! __________________ DGRR 2013 - Year of 13B www.DealsGapRotaryRally.com http://www.facebook.com/Herblenny

02-09-2009, 02:09 PM	#11
Jeff20B Rotary Fanatic Join Date: Mar 2008 iTrader: (1) Posts: 215 Rep Power: 17	I made the picture above because I needed to show the differences of stock carbed intake manifold gaskets, and how you can trim material from the short runner style to have tall runners like a reverse runner '76 manifold or some aftermarket manifolds like the Camden SC, some weber manifolds etc, while retaining a seal around the ACV port, which the mid to late '70s gaskets lack. It was never intended to show the differences in relation to EFI on the later engines. But to answer your question, the T2 and 6 port engines have the same bolt pattern and similar intermediate runner location and height. Mainly the end plates are different. However there is an aftermarket gasket which has tall connected runners on the end plates to work with a T2 and a 6 port. I got it from Atkins. Kind of a universal gasket for 2nd gens and the GSL-SE. Sorry, no pictures handy, and it's harder than heck to deal with pictures on this forum because it has new software which causes all pics to have a size of -1 and they don't display for me. I'm using an older OS. That's why I made such a big deal out of that picture above, hoping that it would work. I checked it on a newer computer and it does display on a computer with XP. Last edited by Jeff20B; 02-09-2009 at 02:11 PM..

02-23-2009, 12:24 PM	#14
warwickben sa rat rod Join Date: Mar 2008 Location: tewksbury ma iTrader: (4) Posts: 408 Rep Power: 17	well if you need a write up for jeffs ignition mod on a first gen i can write one up. the only problem it would be only good for forks with 1980 sa, or one useing the 1980 dizz. __________________

02-03-2009, 10:54 PM	#3
orion84gsl Rotary Fanatic Join Date: Mar 2008 iTrader: (0) Posts: 167 Rep Power: 17	So far I'm still using my 84 12A, so as of yet, no it hasn't been useful. The future however, holds many possibilities.

02-04-2009, 09:20 AM	#4
Kentetsu RCC Contributor Join Date: Feb 2008 Location: Grand Rapids, Michigan iTrader: (1) Posts: 530 Rep Power: 17	Man, there's quite a bit of variation in those intake ports! Thanks Jeff, your work has not gone to waste.

02-06-2009, 02:31 PM	#6
Sterling Premium Vendor Join Date: Feb 2008 iTrader: (2) Posts: 74 Rep Power: 17	That's a great photo, Jeff. Can I use that on my website?

02-06-2009, 05:06 PM	#7
Jeff20B Rotary Fanatic Join Date: Mar 2008 iTrader: (1) Posts: 215 Rep Power: 17	Yeah, sure. But in what context? Are you branching out from strictly carbs to a more inclusive anything to do with intake and/or power adders (ie ignition) format?

02-08-2009, 12:50 PM	#8
Rogue_Wulff Non Member Join Date: Jun 2008 iTrader: (0) Posts: 310 Rep Power: 17	Great pic Jeff. Just for reference, you should have had the 6P and turbo 13B intake gaskets as well. You may not have those gaskets handy, and if that's the case, then no problem. Just would have been nice to see all the variations lined up together. I can't help but wonder if the turbo intake gasket is close to the early 13B, as far as port size/spacing.

02-09-2009, 12:31 PM	#9
Jeff20B Rotary Fanatic Join Date: Mar 2008 iTrader: (1) Posts: 215 Rep Power: 17	The pic above was only to show off carbed intake manifold gaskets. I felt it was appropriate to post here as the title of this subsection reads Carburetors and Carb Tuning.. All info about old school carb set ups..

02-09-2009, 12:41 PM	#10
Rogue_Wulff Non Member Join Date: Jun 2008 iTrader: (0) Posts: 310 Rep Power: 17	Yes, but, there are carbed 6ports thanks to aftermarket intakes. I have one of those. There are also people wanting to use TII engines with 4port carb intakes. I have heard conflicting info about the latter. I don't know if the intake bolts on an early style 4port is the same as the later turbo irons. This would be a case of a pic being worth more than 1000 words.....

02-09-2009, 10:05 PM	#13
Jeff20B Rotary Fanatic Join Date: Mar 2008 iTrader: (1) Posts: 215 Rep Power: 17	I don't think I could do it justice, as my forum time is limited, and I still haven't done an actual ignition upgrade in a 1st gen yet. Plus I don't have access to a running 12A, let alone with a Sterling carb to give first hand info anyway. I appreciate that you'd ask me first, but I'm really not the best person for the job. Perhaps someone who has a Sterling carb and adjusted their ignition could give it a try? Has Jon (vipernicus) messed with his ignition? He's always good for a few paragraphs in his nice style of subjective first hand experiences.