John64

Well this project has been a long time coming, almost a year. I did much research and contacted all those on here who completed the swap (Kevin Landers & Rx7doc thanks!). I basicly did the throttle body delete on the butterflies (2nd gen section) and the wax pack delete. There is alot of modification on the manafold itself such as deleteing the second set of injectors and blocking off a few unneeded vac ports and intakes. While I had it apart I also did the Pineaplle Racing 5th&6th port sleeves.
I'm sorry that I did not take any build pics as it would have made the explanation process so much easier.









The conclusion after only a very short ride:
Well worth the time. Very very responsive!
It idles at around 1100rpm, but this is with out any adjustment.
My god alot of research and part gathering (I got 2 complete upper and lower manafold with dynamic chambers)
More to come as I have yet to get it on the highway.

John64

Just found some pics of the intake with all the deleted parts:

84stock

iTrader: (5)

Personally I would prefer polished over black. Great job though, would really like more details in all the differences noted. Mannnn, a before and after dyno pull would have been awesome, however costly though.

84stock

iTrader: (5)

Congrats on the all the effort and research, not an easy project.

gsl-se addict

iTrader: (3)

Looks good, John. I have an S5 intake sitting out in the garage ready to go on. Just need to pick up some fuel rails and some secondary injectors (or plugs).

Kent

mightymite

iTrader: (1)

[QUOTE=84stock;8113071]Personally I would prefer polished over black. Great job though, would really like more details in all the differences noted. Mannnn, a before and after dyno pull would have been awesome, however costly though.[/QUOTE

you could hit the ribs on top with 200 grit in 1 direction to give it a brushed look

82transam

iTrader: (18)

Looks nice and clean as always, some "during" pictures would have been good for those interested in doing this in the future, but otherwise good stuff!
You planning on doing a writeup or anything on how to do it? We'll have to race next time we meet up, the S vs your SE jk

John64

I could put together all the information I gathered into one place I quess. Most of the info I have I just cut out of peoples posts or got directly from the authors.

TeamSMS

You should do a write-up on all the TB mod's you performed along with the injector plug kit and everything else modded to get the s4 intake manifolds to work. Would help out a lot of people...including me....s4 n/a motor ready to go in....waiting to do some extra little mods to install it.

82transam

iTrader: (18)

Yea I think people would appreciate a little writeup, at least detailing what you had to do in order to get the EGR port to line up on the bottom of the lower intake manifold etc. I'm sure some other SE owners would like to do this mod.

John64

Ok, here yah go.
This is the 2nd gen throttle body modification.
The tb mod....

-remove black big air tube
-Mark all vacuum lines
-remove throttle cable
-electrical plugs

Then the coolant line close to the fire wall.

There are like 5 nuts to losen at the bottom of the intake runners.

and 2 more hidden under the re-egi box seen from the drivers side.

Once out, undo the TB. 4 nuts.

Then remove:

-the machinal choke (where hot coolant runs thru) also has a inline check valve with vacuum lines.

-dash pot

-Unscrew the butter flies, (I've had to drill the screws out) then remove the shaft.

Once that is done you'll need to cover the holes from that shaft on both sides of the TB. I've tapped the holes and put in a bolt on each side and grinded off the excess.

Then put that back together.

Next the coolant line.

You'll need to get a 2 foot coolant line with a 90 degree bend near the end. and hook up the 2 coolant opening together. It'll just just run along side the fuel rail.

After reassembly you'll have to readjust the throttle cable for the perfect idle. and the screw on the RE-EGI box.

There are pictures of this in the 2nd gen section.

John64

S4 (86-88) manifold swap onto a GSL-SE

You can use an S5 manifold, but there is a little extra work involved because of the VDI valve and the need to change the fuel rails and injectors.

Ok here we go:

Locate said S4 upper and lower intake manifolds with dynamic chamber and tubing (make sure you get the 5th & 6th ports). Take your time to clean these very, very well. Carb cleaner and degreaser are you friend along with a lot of wire brushes. You will find a lot of carbon buildup.

Once cleaned I did the 2nd gen throttle body modification. It involves remove the first set of butterflies and mechanical choke, coolant lines and dash pot. I also took out the grinder and smoothed over all the sharp edges in side. You will need some JB Weld to fill in all the holes. People have said that this causes a little hesitation on fast deceleration and some warm up idle issues, but I have yet to see these come up.

I then took out the subzero start up valve, ACV, secondary injectors, and other unneeded items that come with the S4 that where not included on the SE version. Take your time and see what you have and compare what you want to keep. I decided to keep my BAC as it does help with idle control. (You will need to run some hose from the bottom of the S4 intake hose to the BAC) I do have all the main emission equipment removed from my SE, so I could take a few extra items off.

You can reuse your TPS and Air Intake sensor from the old unit as they are the same and plug and play.

The difference between the SE intake and the S4 in size is like night and day, over a 30% increase.
A quick comparison from Max 7’s page: http://max7.rx-7.org/mods/mod-intake.htm


Please note that the lower intake will take some extra work to use it on the SE. You need to fill the secondary injector ports (JB Weld) It does bolt right up, but the ports do not exactly line up. There is a passage that sits directly behind where the ACV is on the manifold side. The SE’s use it to direct air in for the ACV and it sits a little lower then the housing. On the S4 it uses two side ports for the same purpose (I JB Welded these up even tough you don’t have too). You have two options to solve this; either you JB weld this port opening closed on your engine block (I did not like this option) or you get a nice piece on angle iron (aluminum) and bolt it up to the bottom of the block to fill the void. I used some JB Weld just to make sure. Use a nice metal level to be sure your make all the mating surfaces flat.



I ordered all the needed gaskets from Mazdatrix along with the old SE gaskets, so I could compare them. I did this so that I can grind open the intake a little to help make the air flow a little smoother between the motor hosing and S4 runners. They will never line up exactly, but closer the better. The new S4 gasket is a 2 piece metal design that seals better then the old paper kind and worth the money.

Now is the time to check your 5th & 6th ports for operation. You can take a set on neddle nose pliers and turn them (it should be very easy to do). Take note of the orientation of them as they will have to be put back in the same way. I took the extra step of cleaning them to like new condition and adding the Pineapple Racing sleeves. If your this far into it, why not for the extra $50. The instructions come with the sleeves, so I will not go into detail on installing them.

If you decided to do the throttle body modification you will need to replace the coolant hose that once warmed up the wax pack. All you will need is a sample size of the old hose and go to the parts store and get the same diameter 12” long with a 90 degree bend. I put mine underneith the fuel lines and put some plastic wire cover over it for added protection.

Now just put everything back together (I hope you took pictures! I didnt but I’ve been thinking this though for over a year). You will need to redo your vacuum lines, as they will be a little short (good time to replace them anyway). Get the FSM for the S4 and SE to do a comparison of the hoses.



You will have to use the S4 airflow meter as no one has ever been able to make the S4 unit work because a voltage difference in the SE. I attached mine directly to the inside of the lower S4 tubing I got when I bought my manifold. There is a big difference in circumference, so you will need to get a 21/2” plumbing sleeve and put it over the SE meter (it’s about ¼” thick). I then cut off and extra overhang thus making up the size difference. I used all new clamps to attach everything at this point. I had to unwrap the wiring harness a little too free up some slack for the plug to reach. Use your imagination as to how to mount the meter. I used some nice zip ties! I also run a nice K&N cone filter at the end.

I hope this all makes sense, if not please ask questions.

Special thanks goes out to Kevin Landers, RX Doctor and forum for all the needed information. The search button is your friend!

John64

Another usefull links for this:
http://homepage.mac.com/carldavis/intake.html
http://www.pineappleracing.com/index...PROD&ProdID=11
http://www.fc3spro.com/TECH/HOWTO/TBM/tbm.html

RXDad

iTrader: (2)

As always, well thought out and well executed.

The biggest question, however, is how does it run!

RXDad