I'm building a 6-port turbo setup for my '79. I've adapted a TII lower intake manifold to the 6-port block as I've seen some others do. To fix the blunt transition at the face of the iron, I made up an aluminum spacer plate as (hopefully) attached below.



I am aiming for a relatively low-boost setup (8-10psi max), running an S4 TII turbo with heavily ported wastegate, and a front-mounted intercooler. This setup will be run in an SA, probably 3-400 lbs lighter than the equivalent 2nd gen.



I'm looking for aux port sleeve recommendations. The actuators are gone with the na manifold, so options are limited. I am not worried about a small drop in low-end, as I'm assuming the light weight and turbo should compensate. Options are:



1.) Leave them out

2.) Leave the stock sleeve in place, pinned to the open position.

3.) Make up some sort of fixed port insert to replace the stock sleeve.



I'd be interested in recommendations and dyno graph comparisons would be great! Once a choice is made, I plan to port match the adapter plate aux ports to the irons, or the sleeve.



Thanks, Roger.

 

You could leave the sleeve out and contour the port with epoxy steel.

 

That's what I'd do if I didn't have any T2 plates handy. I believe Devcon should work. You might want to get a few more opinions before buying it though.



Hey, if your engine is an S4 ('86-'88), make sure to not run too much boost. You don't want a cracked dowel pin area on your rear plate.

 

Check this out http://www.pineappleracing.com/Prod-pr6pi.html it's an insert that goes into the sleeve. You don't use the actuators but you have to set it in some how I'd use DEVCON steel putty works great. Good luck.

 

Thanks for the input guys. I know devcon, JB Weld, and the like are impressive products, but I'm not confident enough to put a big chunk like that so close to the combustion chamber. It very well may be fine, but it just doesn't sit well with me.



I did a bit of a search, and can find no dyno tests before/after sleeve removal or addition of Pineapple inserts. If anyone knows of such results, I'd like to take a look. It does strike me as odd that a company like Mazda purposefully built seriously flow deficient sleeves. Why go to the complexity of that whole aux port setup and cut a serious corner there?



Jeff, I'm hoping dowel pins aren't an issue if I keep the boost down in the Kindergarten-Grade1 level. I'm not looking for huge numbers. If I had that 20B of yours sitting in the garage, I'd be tempted to go that route instead ;-)



Roger.

 

admittedly, i have never used the Pineapple sleeve inserts, but i've read enough to stories about them to have decided that i would not take the chance ... for pretty much the same reasons i'm sure you said you'd be uncomfortable using those JB Weld and other products to recontour your ports.

 

Yeah, S5 and 20B are virtually identical on the rear plate. The rib from the oil filter pedestal area down to the dowel pin casting is the same thickness, or very similar. The S4 and 1st gen engines lack the rib. Older engines had a thick rib, and R5 engines had a thin, curved rib. It was all in the name of lightening the irons, although the engineers seem to have it done right only on the S5 and later plates. I'm going to boost an R5 13B. It's like one pound heavier per plate than a 1st gen engine. I'll use it until I can afford an S5 T2 shortblock.

 

Devcon is only used to hold the sleeve in place it is not directly in the chamber. If you've ever done a monster bridge or have seen one done you block the whole water passage in the rotor housing and port it out shaping the Devcon. It does not compromise your engine. Hell look at periferal motors even Racing Beat reccommeds you use Devcon to seal the water jacket surrounding the intake and gas/fuel will not break it down. I have a friend that swears on these sleeves and says the difference in flow is amazing. I've never used them before but I'm going to try a set. I've done all sorts of six port setups and am willing to try this one. For $40.00 why not try them won't hurt anything.

 

I also drill through the back and tap it, and put an allen head set screw into it to hold it in place. Even it the epoxy comes loose from the steel, the set screw will keep it from moving.







Edit: Just wanted to add that Ive still got some cleaning up to do of the JBweld with the grinder.

 

You could press in a pliable high temp plastic (nylon, teflon etc) "bowl" in the Aux port so you will be sure it won't crack and get sucked in. Press it in and port it to perfection.



I remember someone here has done this and it worked.