S4 vs S5 N/A intake manifold?
 

Im working on rebuilding an N/A S5 engine but i got this scrap S4 kicking around and looking at the intake manifold the S4 looks like it has better flow but im hearing some conflicting arguments either way. so im hoping i can put this to rest soon which is better any thoughts?
S5
bridge ported N/A
tubular header w/ 2.5" exhaust

The stock manifolds on a bridgeport? The stock manifolds are not suited for bridge ported motors. Not only will the stock ports not flow enough for a bridge, the runners are too long considering you will be making peak power much higher. Also, are you running the stock ECU? The stocker too is not designed to run a motor so heavily ported. Your best bet is some sort of custom manifold and a stand alone.

S5 intake is better...why do you think s5 cars had a significant gain in HP...the intake was one that contributed to that.

What about exhaust, compression bumper, and everything else? The S5 intake didn't do that much.

S5 intake on an S4 car will give 12 whp boost. It does quite a bit, mainly due to the VDI.

But for a bridgeport a custom intake manifold and ecu, as stated above, is needed.

Do you need an S5 ECU to run the TB on an S4?

....or anything else for that matter?

An S5 ECU is completely rewired from an S4, so you can't use it at all on an S4 car.

how hard would a conversion be and would it be worth it??

The LIM is basically the same S4 vs S5, as far as the flow capabilities go.

UIM obviously differs quite a bit S4 vs S5, VDI present on the S5.

If you use a aftermarket UIM the S4 vs S5 LIM choice comes down to which is more convenient for you (is it a S5 or S4 block).

Also note that the major restriction in the LIM is the aux port actuator shaft guides and the shafts themself. Theres much improvement to be had modifying these.

It depends, I am selling a kit to do it for $250 shipped. It takes about 30 work hours for one writeup to do it while keeping emissions.

If you know your way around cars, and its worth 12whp for $250 then its worth it. If you are just starting with cars I would probably not recommend it unless you are mechanically inclined.

thanks for the info guys i was thinking that the switch to the maf did most of the hp gains over the vam setup im running in my svo mustang. But about this bridge port problem is it that it just maxes out the maf as you hit high revs or what is it that holds up the ecu? i also have an N370 computer harness missing injectors boost sensor and maf will that work on an na if i get the rest of the setup? i was working on a pp engine for that setup for later. trying not to go standalone because i have an FD im running at 1 bar with a reprogrammed ecu id rather put a standalone in that one. that said could i run an n/a pp off of the turbo ecu as well and will that stand up to about 10psi with the N370 components if i just do that instead?
thanks for the input

you need a standalone to properly realize the benefits from a bp/pp setup.

The AFM restricts you. The stock computer doesn't have accurate timing tables for that airflow. There's a lot of things wrong with the stock setup for bridgeports.

Theres a write up on doing an s4 to s5 intake swap on here somewhere...i bookmarked it.

PS thanks for backing me up Farberio.

No problem. In honesty though, the S4 LIM is 'supposed' to flow better then the S5 LIM. Though during my research of the swap I found that its negligible at best and not noticed on the but dyno.

Whether or not the S5 manifold flows more than an S4 in a static test is irrelevant. There's more to power than just static flow. I've had things on the flowbench that boggled the mind but worked so only results matter. The results speak for themselves. The S5 manifold makes more power based on tuning benefits and not flow. When in "long" mode without VDI actuated, the runners are physically longer than the S4 manifold meaning it is tuned lower. With VDI actuated, although the air doesn't travel a physically shorter distance, due to the VDI valve providing a shorter distance for the return pressure pulses to travel back to the other side, the runners appear shorter to the engine which tunes the engine to a higher rpm than the S4 runners. The S5 manifold does increase power over an S5 manifold as a result. It's been proven many times. It's good for up to 15 hp more over stock or so. Maybe a little less, maybe a little more. Power also holds strong to a much higher rpm than the S4 manifold does too. It's a better manifold to use but only IF you are using a stock or streetported engine. A bridegported engine shouldn't be using either and it should only be using a standalone ecu or carb to control things.

Actually the VDI system is almost entirely responsible for the S5's power increase. The exhaust was unchanged, the tiny increase in CR would give 1-2hp at the most, and the "everything else" you mention was virtually nothing else.

What I was told about the S5 intake being better like NZConvertible stated was true. The VDI really gives you the 1-2hp more. The VDI is to eliminate the Back Pressure that comes up trough the intake. I was told. The S4 Doesn't do that. http://www.youtube.com/watch?v=-5mM-m23n40 This vid is a S4 intake on a half bridge. I know it doesn't help but you might see the results.

No, it's responsible for most of the S5's 14hp peak gain, plus a broader spread of power through the whole rev range.

Completely wrong on several levels... :( How the VDI system works was explained only two post up.

Ah, my misunderstanding.

I learn something new everyday :).

The VDI is explained in the FSM.

If the VDI only gave a gain of 1-2hp, then why did I and many others spend the countless hours swapping to the S5 intake and making it work?

From experience, 1-2hp is BS. You get a big push in the seat when the VDI kicks in. I say around 10-12HP. I havn't seen a back to back dyno yet though. I know its over 10hp gain.

ok ok ok.....so around how much gain would u get with s5 manifolds on a ns s4....and is it bolt on to the engine or do u need to do any conversions..?

sorry typo i ment n/a

http://homepage.mac.com/carldavis/intake.html
I am selling most of the parts needed for $250.

Alot of people on this site will do alot of work for little or no gains. Alot of skeptics here, including some misinformed people like myself ;).

And that's the slight issue, people also are big on "dyno" results, or some kinda track result. Having a butt dyno result from alot of people really won't make alot of people go bonkers over doing alot of work for someones seat of the pants experiences.

For example, on Cavaliers alot of people swap an intake from an older motor, everyone said it felt better then the old one. Some guy went and did before and after dynos and lost 14HP and 10TQ. It shows that the butt dyno is hard to beleive.

so what kind of porting can i do to a NA engine if i do not want to go to standalone ecu and if i half bridge should it be on the primary or seconday and what should my expected hp gains be? also could a mega squirt or some other piggyback help me out instead of a full standalone. also could the n370 stuff help me out here or is that useless without a turbo i was thinking that the timing was dependent on boost right or wrong there. people also said i couldnt squeeze 300rwhp out of a 4-cyl mustang but i drive one, and i cant let a ford beet a rotary.

this is why i drive an FD now more air more power less BS.

My personal opinion is that you should never run a bridgeport or any kind on a naturally aspirated engine if you are still running a stock intake manifold and/or a stock ecu.

OK here is a question that may or may not have any relevance, what about an intake from an RE motor? what kind of headache is that to swap on and any idea as to what gains? my guess would be not enough for the headache but I have been wrong before.

I also know where there is a wrecked RX8 which might have an intake too LOL but that would defiantly be crazy talk.

ok before I destroyed this thread .....

You can gain over 10hp swapping the s5 intake onto a s4 n/a.

I forgot about that dyno graph. I would like to know how is engine was tuned.

His power ends about 6800. Mine ends around 7500.

He gained about 8hp +/- from studying that graph. I had to put it in MSPaint and draw straight lines to the edge.

But just saying it "feels" better isn't going to sell, having that dyno handy is helpful.

Bloody, I'm one of the guys on here who believes a half bridge is a waste...it gives you the cons of a bridge port without the proper power...IMO its just a half assed port..go for a full bridge. And to gain the maximum power potential aftermarket///custom intake and exhaust is an absolute must....standalone also to tune the living shit out of and extract every little bit of hp.

I thought the S5 AFM was also responsible for the power increases.

Have you tried it? No? Then don't speek. Using the VDi is a large kick in the ass compaired to the s4 manifold.

There have been others that have seen back to back dynos with 10hp +/- gains from the manifold. Just because I havn't seen one except the one above doesn't mean its not possible.

Why don't we all just say its only worth 1-2 hp since thats what everyone thinks :lol:

Ive tried it, its not that big of a difference. Its not worth the effort, and I would not do it again. The biggest difference is a mildly stonger midrange, everything else was exactly the same. Also if it counts for anything I lost 3mpg.

I see that reading fundamentals is not a requirement on this forum.

I don't really know how to say it anymore clear.

What I said is that people like YOU just go around saying it's worth it because it FEELS better. The dyno is what proved anything to me, but without that it would come off as speculation. And for the amount of work it is why would anyone want to take on the project when the gains are: "It feels better".

Fuck, people said SDJ headers "felt" better but we have no clue if they are because noone has one. It's just a butt dyno and butt dynos lie, and it's like a LS1 before and after cam where there is no doubt in your mind that you're going fasster.

And back to back dynos, even the same day? That project doesn't exactly look like a walk in the park to come the same day.

I am NOT ARGUING the fact that it gives 10-12 HP, the other dude already posted the dyno (too bad the torque numbers where pretty subpar :().

But simply, I am saying: Having ANY kind of proof is better then telling everyone "it feels better" and it "does give 10HP because I felt it pull way hard".

Now before you SPEAK, re-read what I typed before and learn that I'm just annoyed by the way you went about things, any proof is better then "it feels better".

I actually, finally, agree with you.

After what 3yrs.

14hp from an AFM?! :rlaugh:

The AFM does practically nothing for power (proven).

"It feels better" is a pretty vague discription of how much of a kick in the ass you really get.

I don't go around saying DO IT because it "feels better". I made a true CAI for pressure you think im going to say do what i did because it feels better? Nope because it probubly wont do anything on someone elses engine.

Many people have done the swap and MANY people will suggest doing it because MANY people have the same kick in the ass feeling unless something else is wrong which if you read the numorus threads about the swap instead of making a new one asking the same questions, then you will see some of the issue you may face that could lead to less or the same power output after the swap.

Others will also forget about the stock exhaust that is HIGHLY restrictive. They may do the swap and think its trash what in fact they have done nothing to the exhaust besides a CAT back and are not thinking about the clogged cat.

I would like to know where you think the S5's extra power came from? Answer me that.

Completly different expereice from what I had when I first put it on beside the mid range. VERY strong pull from 5000 - 7500. I even put the S4 mani back on one day and it felt like shit ending at just after 6000.

But that's what you where saying, read the other posts.

For pressure? I don't think I get what you're saying there. But before a dyno was posted, you just said "it feels better" about the S5 intake, that is what had me irked.

Beleive or not, my engine guy at the time told me not to even mess with the stock N/A intake manifolds. He also has made alot more power on his car then, well, 90% of the other NA guys. He advised me to go TII or custom.

But again, I'm not arguing that the S5 UIM isn't good. Which is why I wish you would read my prior posts, my personal opinion was it was just not worth the time and effort to the average dude. But if someone else has the time and effort, more power to them :).

That isn't exactly a secret.

Alrighty.

I already admitted that I was wrong about it in an earlier post (which is why I urged you to read UP in now two posts). But again, I'm not arguing it. I'm just not happy when people like you just give a butt dyno and tell people that's the only reason why (If you read my cavalier reference). A little proof goes a long way and if I was a novice asking the question, I know I wouldn't want a guy to say "It feelz way better yo".

It's simular to that Cavalier thing I noted and the FD UIM results.

Less resistance equals increase in pressure. Having the filter in front of the rad also aids in pressure increase.

Does this engine builder have experience with both manifolds? It really depends on your setup. If your going for large ports then Custom intake manfiolds may be the way to go. Going turbo is a different world and has nothing to do with the n/a intake manifolds. Obvesouly your engine builder wants more power then the n/a can put out. Thats fine, everyone has their desires.

90% of the other n/a guys have no money. Its takes a lot of money, skill, tuning, and time to make a lot of power on a n/a. Obevsouly the stock manifolds have their limits which most of the time is not reached unless you are going with a very large street port. The S5 intake manifolds would be usless on a b-port engine as well. Money, time and skill it takes to go outside the limites of the manifold and start making some power over 200hp


Average dude, maybe not, I suppose it depends on what average means. I don't know how you can make an opinion on something you have no experience with. You only have seen a dyno graph with no other information about the engine setup. You don't want to beleive the many people that have done the swap, fine, but don't start telling people its not worth it when you have no experience with it.

Its not like doing the TB mod and saying, "ya it feels better in the mid range and top end" when in fact nothing has changed in the aspect of performance. You don't have to "think" its better or make your self believe it feels better like many do with the TB mod. When I say, kick in the ass, I mean a very hard acceleration but that means nothing to you I know.

I've made my point already, I don't see why you're still replying.

What's funny is "I" used to be one of the "all motor" preachers on this forum. You're just repeating information I already know and arguing with me for no reason.

Don't assume that I haven't messed with it or been involved with cars that have done it, which you have been doing since my first reply.

S4 N/A cars used 2 monolithic "pre" catalytic convertors. Mazda deleted the first monolithic cat on the S5 cars. Whether or not this affects power, or by how much, I don't know, but the exhaust systems were not the same.

You're right, I stand corrected. I doubt it would have much effect on power though, considering how restrictive the rest of the system is. The Japanese FC's have no pre-cats and are still quoted at the same power as US FC's. ;)

Let's just keep things simple. All of you people who always demand dyno proof for everything (let's ignore the fact that a dyno is a 2D representation of only a fraction of a 3D powerband and doesn't tell us much!), just keep what you are using and be happy with it. To those that are intelligent and actually do realize that an S5 manifold is superior in every way to an S4, use those. That way everyone is happy!!! It's a win-win situation.

I've used both an S4 and S5 manifold. If anyone claims to have also used these and says the S5 doesn't make anything additional that can be felt, quite frankly something is wrong with your engine! Get that fixed! You'll never feel anything beneficial until you do. I currently have an S5 manifold on my ported engine. I also have an S4 lying around as well as S4 and S5 TII manifolds. I've even got a 1 piece Weber manifold lying around. For street use the S5 n/a is very hard to beat. It's a worthwhile mod. It does far more than any cone filter or ignition upgrade could ever hope to so yet people do those all day everyday. I just don't get it.

These are just my observations though so if you've had different results, good for you. Use whatever makes you happy.

So on n/a s5's this VDI makes amazing?

I never notice anything past 5k rpm :s just keeps going till the redline.

I think ignoring that fact is a good idea in this case, because the VDI doesn't really help in part-load or transient situations. It's really only beneficial at full throttle, which is exactly what a dyno shows.