S5 intake on S4?
 

Found a S5 intakemanifold for 85 bucks.

Power gains?

none

Power gains are minimal. Save for something more worthy.

edit:
Bah...Rotarygods post is far superior...read one post down

Why do people keep saying none or minimal gains? That's not true. You can pick up roughly 15 hp on the top end and extend your powerband across a wider range. It's definitely beneficial but you have to keep VDI and the aux ports working.

I have no doubt someone is going to try to compare the power of an S4 to an S5 and point out that there is only a 14 hp difference between them even though there is a better afm, different intake manifold, and higher compression. However this would be completely ignoring the fact that at full throttle the stock S5 runs in the high 10 to low 11 afr's and hence is being severly held back in power as a result. While the S4's do run rich, they aren't that rich. Tune each engine for it's optimal output and you'll see far more than a 16 hp difference. The S5 intake is superior to the S4 any day of the week. Sorry to burst some people's bubble. Don't base flow or potential on what each looks like. Air doesn't always do what you think it will and if you think it's better and more beneficial through an S4 intake, you just proved my point! Keep in mind different porting style like different things but for street use the S5 is king.

Now saying all of this, it's not quite a simple swap. There's alot to do to make it work properly so don't think you'll be done in half an hour with a perfectly running car with more power. It's the people that do it this way that typically regret the mod and proclaim it a failure.

BTW: I currently have an S5 intake on my streetported GSL-SE first gen. It works great! I used to have an S4 intake.

Well Id just have it installed when i have my engine rebuilt. So worth 85 bucks? Also would I need an S5 throttle body? Found one of them for $50. I am also getting a streetport done.

Did you use just the S5 UIM, or the S5 UIM+LIM?

The power band from 4k to 7k becomes almost completely linear with the S5 manifold and working VDI. I converted to the S5 manifold on my S4 NA motor (before going turbo), and easily felt the extra pull up to redline. And as mentioned already, it was not a simple mod. I spent the weekend mostly trying to get the block ground down the right amount to get the UIM to seal against the LIM. My advice is grind it a lot more than you think you need. Bending the OMP rod correctly is also a pain in the ass since it just barely clears the UIM and alternator nut (I cut this nut down to fit better).

I attached Silver88GXL's dyno of the results, as well as some pictures of my manifold setup and my S4/S5 hybrid vacuum diagram that keeps all emissions (except EGR) intact.

Writeups: http://homepage.mac.com/carldavis/intake.html
http://howto.globalvicinity.com/gv_w...i=63&co=1&vi=1

Edit: I used the S4 LIM & TB, S5 UIM, S5 primary and secondary fuel rails, 2 rpm switches (6PI & VDI), 2 egr solenoids & a modified stock airpump.

so is the s5 throttle body not required then?

No, the S5 TB has no place for the S4 TPS or the OMP rod (not needed if premixing). You use the S4 TB and TB spacer for this.

I've contemplated doing this swap before, I'd imagine it's much easier if you have no emissions and premix (no OMP)? If that's the case, all you'd need to do is all the physical modifications to make it fit and find a way to make the 6pi and VDI systems work, right? I'm reading through the guide right now, but figured I'd ask anyway.

It's easier w/out emissions or the OMP, but the metal work is the main reason for it being a "difficult mod". Grinding the block is harder than it sounds since all sorts of things stick up in the way and make it hard to get the right angle w/ a die grinder. A cone shaped grinding stone seems to work the best for this part, but it still takes forever (even w/ an air powered grinder). Then there's the slotting of the S5 UIM if you keep the S4 LIM. A lot of metal has to come out of the rear intake runner to allow you to redrill the hole for the stud and allow a nut to fit in there too. If throwing out emissions however, you can use the S5 LIM and avoid this part.

Attached are pictures of the modified UIM and the ground rear iron.

Thanks :icon_tup:. I'm planning on rebuilding and street porting my motor in the spring/summer and I think the VDI will really complement the port.

The whole thing upper, mid, and lower but I used an S4 throttlebody. My car had no emissions. It was going on a 1st gen anyways. Making the VDI work was a bit of a pain. As was mentioned, rebending the omp rod really sucks. I retrofitted a Mustang tps (which is no simple task!) since I use a Megasquirt. I too had to grind the top of the rear housing but the bit for my die grinder will get rid of it in less than a minute!

I love the powerband width. The car just keeps on pulling up top. I've got my rev limit set at 9000 and it's still strong up past 8K with no problems. When I had the S4 manifold there was no point in shifting much after 7K and it was a big improvement over my GSL-SE manifold which was pointless above 6.5K. I honestly don't really see much of a difference below that level. It's the top end improvement and extension that I love about the S5 manifold. I drove around for a while with VDI wired open and the aux ports open and I hated it. Talk about gutless on the low to mid range! I think alot of people are too lazy to make it all work properly and as I did with the same incomplete setup end up hating it.

The S4 manifold is definitely simple. I've even seen someone mention wanting to retrofit it to an S5 car. That made me laugh but sadly was based on people here bashing the S5 setup. There is a way to modify the hell out of an S4 manifold and make is powerful as hell compared to stock but the powerband will shift upwards. It also involves cutting it in half, doing a bunch of work, and then welding it all back together again. Low end and drivability suffer alot though. For a race engine it would be fun but for street not so much.

If you do the S5 swap, take your time, be thorough, and complete it. Make everything works including the VDI and aux ports. Again I have no idea why people like to disable them. Been there, done that. Make them work!

Ok I think Im gonna go for it. After I install the manifold, get it rebuilt, ported and tuned, ill definitely be able to tell it by the seat of my pants. 148whp can say goodbye and hello to about 190 :)

I tested the intake manifolds, I don't know if there is much difference, I think I had better results with S4 intake, the power bend was much smoother. Also I did it on S5 ECU, the whole car was S5 except engine, engine was S4, red line on S5 is higher, on S4 car S5 manifold for me , would be worthless.

But for you, how else would you learn with out trying it !?!

I wouldnt know with the mixed reviews im getting haha

You got to note that S5 rev higher than S4, that is why the S5 manifold would be better for S5.

For me I wouldn't bother with S5 manifold on S4 everything else, instead I would just do some work to S4 manifold.

No No No. The S5 Manifold adds power over the S4. Its better on both applications. Unless you are going for an all out motor, in which case you have no business using either of the stock manifolds.

This is straight from Icemark when I asked him about the debateable part of the power gains in a PM.

"On the intake manifold it depends on what you are doing with the motor and what the motor is (S4 vs S5 and non turbo vs turbo).

I am assuming you have a S4 non turbo and are thinking about using a S5 non turbo intake runner system... if so, the discussions and testing over the last 10 years have come down to the following:

If you have a non turbo S4 motor the gains that can be found are at the top end (6000+ RPM). Typically breathing for the S4 intake runs out in the high 5800-6000 range, while using a VDI you can get pretty stable breathing up to the redline of 7000 RPM. So your gains are really only at peak RPM. But there is a downside... because the S5 lower intake runners are slightly smaller (to help keep up intake velocity) it compromises mid-end torque (3000-4000 range)... to fix this really a combo manifold using the S4 lower intake , while using the S5 middle/VDI and top sections (port matched to the S4 LIM) gives the best power potential.

Then you can get a pretty stable across the board stock powerband until you hit the 5000-5500+ RPM where you will see moderate peak increases (anywhere between 2 and 14HP peak power increase based on dyno tests).

But sticking with the all S5 intake runner system on the S4 motor showed a typically loss of around 10 HP and 5 FT/LBS until 4000 RPM. At 4000 RPM the power line leveled off and as the engine approached higher RPMs power increased slightly.

So you are probably wondering what this means to you?

Well if you have already made exhaust and intake filter changes that have shown positive HP increases on the dyno, then using the S5 VDI and upper section will net you some more power back (again anywhere between 2 and 12 HP peak). But if you have not made any changes that have increased power, just bolting in the intake, will not net you much at all.

The other thing to consider is that the stock Mazda ECU can not keep much control over the coils much past 6500 RPM. So even if you bolt in the intake to make it capable of producing power all the way up to 7000 RPM the stock ignition may run out before you can take full advantage the better breathing at high RPM. This means that you will probably need to look at a CDI ignition system or coil amp to get better control back... of course then you are spending more money.

So it comes down to, do you need to make max power to 7000 RPM? or is the normal 6500 RPM fine?"

Also note that, S4 lower intake manifold one bolt pattern ( by the firewall ) will not match with S5 upper manifold.

i want a NA FC so i can play with this stuff 2,im bored with my turbo.

That's alot of good info from Icemark. :icon_tup: :icon_tup:

Also, I think my rev limiter is broken, because I've had my S4 to 8k before. heh.

This is what Chris Sanders at Banzai shared with me.

"It requires grinding of the rear plate to fit and you loose the ability to have 5&6th ports actuate. It is also impossible to actuate the VDI with the S4 ECU. The dyno chart that you reference is an S4 block with S4 intake. The real gains come from the higher compression lightweight S5 rotors, not the intake."

Then Chris Sanders is a complete and utter nincompoop and is talking about things he has never done before.

Read these

Also
http://howto.globalvicinity.com/gv_w...i=63&co=1&vi=1

and

http://www.globalvicinity.com/images....9577_2807.jpg