Yep, its on, and running...good!

I installed just the upper half of the manifold. The factory manual calls it the 'dynamic chamber', and so i'll call it dc for short....

The 2nd gen's dc is 1" taller than the 1st gen's. That's its primary advantage; as the runners that the engine breathes though up to 5000rpm are longer because of the extra height - and so (in theory) produce more torque.

The layout on the inside of the 2 dc's are basically the same; however - again due to the height difference - the 2nd's gen dc is absolutely 'cavernous' compared to the shallow 1st gen's dc. Anyone who compares them will know what i mean....

Also, the whole basic casting outside AND inside of the 2nd gen's dc is cleaner, and just strikes me as truly 'made for airflow' when compared to the 1st gen's. An example...when you look *inside* the 2nd gen dc from the bottom (the VICS passage), you see the *round casting* of the #1 runner - whereas on the 1st gen, you see the casting for the *relief* on top of the dc that says "INJECTION".....maybe minor but hey the 2nd gen's casting is just geared for flow - not for looks as in the 1st gen's!

One other thing, because of the height, the 2nd gen's VICS chamber is that much larger - also the openings (passage) out of the main chamber AND into the VICS chamber are about an 1/8" larger than the 1st gen's.

Install....see next post

 

i'm gonna have to assume you mean the 1.8L BP that came in the 95 2nd gens...? as the 1.5L intake manifold looks like a header, for lack of a better word...

and where's the next post.........................????????

 

It bolts right on....but there's a WHOLE lot more to the story

how/where to begin....

you'll have to disconnect some coolant lines.....leave the radiator cap on tight! if you take the cap off, most all your coolant will leak out. you'll lose only a small amount IF you keep it on!

how about differences and what to do:
1) the 1st gen throttle body(tb) and isc valve are COMPLETELY different - and physically smaller - than the 2nd gen's. It would have been super simple to have been able to use the 2nd gen's tb, but there is NO reasonable way of adapting the 1st gen isc valve to the 2nd gen tb.....

so i fitted the 1st gen tb to the 2nd gen dc. in order to do this, you have to grind away 3 different points on the 2nd gen dc: for the a) tps sensor b) small pipe flange at base of tb c) dashpot area. why? the neck on the 2nd gen dc is thicker/wider - AND so the 1st gen tb doesn't sit flush. i used a grinding wheel and later, a drill bit.... which actually made removing material much faster.

2) i used JBWeld in 2 places: a) on the 2nd gen dc, there is a cutout for the isc valve's air to flow in....its the OPPOSITE location of the 1st gen's isc valve. i plugged the cutout with the JBWeld - if you don't fill it with something, you'll have a massive air leak! b) the 2nd gen dc has an opening (underneath) near the middle rightmost bolt-hole for i assume an egr valve. which we don't have! so i just used a small piece of scrap metal to cover the hole and plastered it on with the JBWeld.

speaking of that middle rightmost bolt-hole - its the ONLY one that doesn't match up with the 1st gen's lower manifold. i'm not worrying about it - it didn't strike me as an important bolt location for the manifold gasket - you'll see what i mean....

3) the 4 mounting holes of the 1st gen's tb ONLY match up to the 2 *upper* holes on the 2nd gen dc. i guess you could weld/JBWeld the 2 lower holes on the dc and tap/redrill for the 2 lower tb holes......but i risked not doing it. when installing it, i just used some hardening gasket sealer on the dc, both sides of the 1st gen tb gasket, and the tb itself to help insure a good seal; and so far it appears to be working.

4) on the underside of the 1st gen dc, there is an air valve that increases the idle for cold starts. the 2nd gen dc doesn't have it.

i chose to go without it. if you do the same, it may cause problems when it comes to passing emissions inspection, etc. as i understand it from the factory manual, without the air valve; when you start it, the engine will idle @ 750rpm just like it does when it warms up. so if its 0 degrees outside, no more automatic ~1600rpm warm-up idle, just 750.....

the air valve has 2 coolant lines - one comes from a main coolant pipe and one goes to the isc valve. so to install the 2nd gen dc without the air valve, you have to do some coolant line rerouting....
AFTER removing the 1st gen dc and air valve WITH its 2 coolant lines ATTACHED, you'll want to connect the isc valve to the main coolant pipe. use the longer coolant line off the air valve to do this.
the isc valve also has 2 coolant lines: one going to a main coolant pipe....AND the one THAT went to the *air valve*. DO NOT reroute the isc's line that goes to the main pipe! JUST reroute the isc's line that WENT to the air valve so that it connects TO the main pipe that WAS ALSO attached to the air valve.

IF YOU GET THESE CONNECTIONS WRONG, YOU MAY HAVE HAVE SERIOUS COOLING RELATED DAMAGE SUCH AS A BLOWN HEAD GASKET, WARPED HEAD, etc!!!

5) the 2nd gen's pcv hose nipple is not on the front of the dc like the 1st gen - its on the back side next to the tb. i used a long silicone hose to make the connection.

6) the throttle cable mounting 'flange' on the 2nd gen dc isn't quite 'in line' with the 1st gen dashpot....there's a slight angle/deflection to it; but i've had no trouble so far with it - doesn't SEEM to be a concern.



WHEW!!

all the other vacuum hoses connect to the right places; BE SURE TO INSTALL THE BRAKE HOSE IN THE RIGHT DIRECTION! (the right direction is marked on the hose itself) It has a valve in it that only flows one way - if you get it backwards, you'll have no POWER BRAKES!!

well, that pretty much sums it up! it wasn't exactly easy, but with some patience and just common sense it CAN BE done.

Performance thoughts next....

 

2nd gen 1.8l BP....in this case off a Sephia!

and that 'next post'.....well..it took me....~2 hours to figure out how to write!!!

 

Took the car out and wound it out to 7K several times and it just feels strong!

Its all subjective/relative but it really does seem to have more muscle. One example of something i've honestly never noticed before: in 4th gear, i was around ~2500rpm just cruising, tapping the gas pedal; then letting off....the car had more of a tendency to 'kick'/'buck' than i've ever noticed....hard to describe but there just seemed to be better throttle response - i took it as more torque

High rpm felt great too, and i don't even have the RX7 VAF on right now! One thing i forgot to mention, i did grind away the ridge in the 1st gen LOWER manifold where the VICS passage is. i think bpt323 posted some pics about this mod. the 2nd gen lower manifold did not even have this ridge, so i just ground it away. I DID NOT grind away any of the ridge that divides the VICS passage in the 2nd gen dc....

Well, we don't have V-TEC, but at least Mazda did give us something that definitely enhances airflow: VICS! Its really a pretty neat system, and the 2nd gen dc seems well designed to make the most of it.

 

Good job on the install, sounds cool... but I'm waiting for the dyno results!

 

Thanks! No $$$ for dyno so i'm afraid that'll have to wait.....i'm gonna go out on a limb and say that it did for me the same thing that the header did - maybe another ~6+ ft lbs and ~5hp....whatever the case it definitely complements the header and other breathing mods.

If i can what i'd love to do eventually is combine my current setup with 10:1 compression, a standalone, custom cams, and some minor headwork - that should result in some really decent power

BTY i was really surprised at how clean my intake manifold and dc were!! Especially after 12 yrs, 218K! The VICS butterflys were nice and golden - just a little coating of oil throughout. The 2nd gen dc/im were VERY dirty/black in comparison....

My tb was definitely in need of a cleaning, however - the back side of the throttle valve was black with soot.

I do still have a HIGH idle....i *think* its because of a bad isc valve. I sprayed some cleaner in the isc valve and that may have done it in.... Whatever the case i don't believe its due to the install - i think if you do it right, and get everyting properly sealed, you'll be good to go.

Ok, one other thing i failed to mention that's also important for the install:

the 1st gen tb has a small opening at the bottom for flowing air to the air valve.....the 2nd gen dc doesn't (since it doesn't use the air valve). so, you need to cover that opening on the tb, or else *some extra* air will make it into the dc and thus cause a high idle. i simply used a small piece of aluminum foil and 'sandwiched' it over the opening and between the tb and tb gasket..... it appears to be working out just fine with the 'hardening gasket sealer' that i used when assembling it together.

 

Don't worry, we'll forgive you Wil....

The 1st pic in this thread shows the 2nd gen dc/tb pretty well:

http://www.protegeclub.com/forum/sho...threadid=27145

as you can see the 2nd gen tb doesn't even have a dashpot like the 1st gen's....

the only reason i happened upon this is because of a friend pulling the BP motor from a Sephia for use in a Miata....he didn't need the manifold so i snagged it. once i got to looking at it, the wheels started turning....

....i don't even know what year mine came out of - so they used a different manifold on the 99??

as far as that 'slight difference in height', it really doesn't *seem* like a big deal; but as i posted in another thread, that 1" is a 33 percent increase in height over the 1st gen's dc!! the 1st gen's dc is 3" - the 2nd gen is a solid 4"!

as far as hp/torque #'s, i'm just hazarding guesses obviously; but it does really seem to be comparable to the TYPE of gains that the header produced.....with probably better torque gains than high hp gains.

 

the 1.5L 2nd gen many is a 2 peice Wil ...
bruce