[84Reasons]

Hi All,

Just a post to show what can be done with the N53 engine in a 325i for anyone who owns one and a celebration for me after a finally finding someone who can map the car!

Fitted the 3 stage manifold from a 330i to my 325i a while back now and struggled to find a tuner who could map the car to use it properly, after a while and a recommendation from another forum user I tried Map-Tech!

These guys have done amazing and got a healthy 60hp & 55nm of torque out of the NA engine due to BMW using de-tuned engines in some models.
These engines are so de-tuned from factory in a 325i that you'd still get about 30hp out of it without the manifold!

If you have a N53 325i get down to Map-Tech!

May post some more mods I've done to the car at a later date !
MAP TECH DYNO by Harry Reason, on Flickr

[Markos ZimZimma]

If only they were based in the south somewhere!

Great results though in terms of BHP/torque... How does it feel/drive now?

I'm pretty clueless on maps but was wondering if you or anyone else knows why the torque curve is a little 'lumpy'? Does it drop off for gear changes? That's my best uneducated guess as the slight drops appear at the same RPM on both power and toque curves.

[84Reasons]

Originally Posted by Markos ZimZimma

If only they were based in the south somewhere!

Great results though in terms of BHP/torque... How does it feel/drive now?

I'm pretty clueless on maps but was wondering if you or anyone else knows why the torque curve is a little 'lumpy'? Does it drop off for gear changes? That's my best uneducated guess as the slight drops appear at the same RPM on both power and toque curves.

Yeah it's annoying- but I spoke to Gareth (the guy who runs map tech) and he doesn't think anyone down south can map the manifold as it's apparently quite complicated! I had it tuned by a different company before who didn't get anything out of it so I'm inclined to believe him!

It's like night and day to be honest. Completely different car now and feels a lot more alive. Feels like it should have done from factory- feels almost fast!

I believe the drops are due to the valves in the 3 stage manifold opening and closing at different points, apparently it's a good indicator it's working! I believe they are fully open at low rpm, halfway at mid range then they close at the top end. It's all designed to give you more torque at the low end and more hp at the top end!

[Markos ZimZimma]

Originally Posted by 84Reasons

Yeah it's annoying- but I spoke to Gareth (the guy who runs map tech) and he doesn't think anyone down south can map the manifold as it's apparently quite complicated! I had it tuned by a different company before who didn't get anything out of it so I'm inclined to believe him!

It's like night and day to be honest. Completely different car now and feels a lot more alive. Feels like it should have done from factory- feels almost fast!

I believe the drops are due to the valves in the 3 stage manifold opening and closing at different points, apparently it's a good indicator it's working! I believe they are fully open at low rpm, halfway at mid range then they close at the top end. It's all designed to give you more torque at the low end and more hp at the top end!

"325i" + "fast" don't often go in the same sentence...

I'd be looking at just a remap without the manifold but I'd like to find someone who has definite experience of mapping an N53 325i... when/if the madness calms down I'll start looking again.

Makes sense regarding the stages of the manifold and the points on the lines...

Overall it sounds good though, well worth the trouble to source/fit the manifold and get it mapped properly, well done!

[Phil325i]

Impact on fuel consumption OP? More power is only possible with more fuel, so I guess consumption has worsened...or is it too early to tell yet?

[Phil325i]

Originally Posted by Markos ZimZimma

was wondering if you or anyone else knows why the torque curve is a little 'lumpy'?

Looks like the 'lumpy' period in the rev range might coincide with when Vanos is in operation...

[84Reasons]

Originally Posted by Markos ZimZimma

"325i" + "fast" don't often go in the same sentence...

I'd be looking at just a remap without the manifold but I'd like to find someone who has definite experience of mapping an N53 325i... when/if the madness calms down I'll start looking again.

Makes sense regarding the stages of the manifold and the points on the lines...

Overall it sounds good though, well worth the trouble to source/fit the manifold and get it mapped properly, well done!

Haha true!

Yeah it's still worth it and easy quick gains!

Thank you ! To be honest the manifold wasn't too expensive or hard to find and whilst it was frustrating to fit it wasn't too bad if you have someone around to help!

[84Reasons]

Originally Posted by Phil325i

Impact on fuel consumption OP? More power is only possible with more fuel, so I guess consumption has worsened...or is it too early to tell yet?

Probably too early and I'm not sure if I ever will be able to tell as when being mapped Gareth asked if I wanted to map it for 97 unleaded for a small gain , he reckoned it wouldn't be much difference but I thought might as well haha, so I've been using mainly 99 recently and only used 95 before so to hard to tell really!

[Markos ZimZimma]

Originally Posted by 84Reasons

Probably too early and I'm not sure if I ever will be able to tell as when being mapped Gareth asked if I wanted to map it for 97 unleaded for a small gain , he reckoned it wouldn't be much difference but I thought might as well haha, so I've been using mainly 99 recently and only used 95 before so to hard to tell really!

Years ago I tested MPG on a 3.0l Alfa GTV with normal and super and I definitely got better MPG from super unleaded, in fact the extra MPG covered the higher cost of Shell V-Power. Nowadays I still stick V-Power in but the differential in cost has grown so there's no way it balances out anymore.

But anyway, I think you'll find the remap has added a little extra weight to your right foot so even with higher octane fuel your MPG might drop a little!

[Chappers 71]

Nice gains, good job

[84Reasons]

Originally Posted by Markos ZimZimma

Years ago I tested MPG on a 3.0l Alfa GTV with normal and super and I definitely got better MPG from super unleaded, in fact the extra MPG covered the higher cost of Shell V-Power. Nowadays I still stick V-Power in but the differential in cost has grown so there's no way it balances out anymore.

But anyway, I think you'll find the remap has added a little extra weight to your right foot so even with higher octane fuel your MPG might drop a little!

Yeah exactly I'm still definitely in the hooning it everywhere period haha

[H325i]

How much did this cost for you to do? Picked up a 325i M Sport recently and while it's not something I would do so soon, maybe it's something for the future if I want more out of it

[84Reasons]

Originally Posted by H325i

How much did this cost for you to do? Picked up a 325i M Sport recently and while it's not something I would do so soon, maybe it's something for the future if I want more out of it

£100 quid and a couple hours graft to fit the manifold (2nd hand) will cost more if you get a garage to do it, not sure how much.
£300 for the remap with maptech!

[rnyassar]

Hey guys,

I thought I'd weigh in on the situation. I've recently bought and fitted a 30i inlet too. Though I had my car mapped a few months ago without it. On the dyno with purely a stage 1 and a muffler delete, this is what my car achieved.

Dyno graph.pdf

I'm quite surprised that you achieved only 263.4HP with the inlet manifold.

After this dyno, I installed a Mishimoto silicone intake boot as well as a K&N air filter. I did not feel much gain, maybe a slight bump of power around 2500 rpm and 5500 rpm. After a few hundred miles, the car began to subtly burble on overrun. I noticed that the engine revved more freely too.

A month or so later, I removed the secondary cats. I could noticeably feel slightly more top end power, and at the lower/mid RPM, the car felt slightly more urgent. The burbles were now amplified 10x in volume. I then took the car on track to compare the top speeds.

With just a stage 1 and muffler, my speedo dial read 155 mph as a maximum, however, after these extra few mods (not incl. the 3 stage manifold), my speedo dial reached the limit, it was showing approximately 165 mph as an end stop - though I felt it was still increasing in speed.

After fitting the 3 stage inlet manifold, I allowed 100 miles for the ECU to adapt. I noticed after 30 miles, my burbles stopped - I'd like to point out that the car was never mapped to include 'pops & bangs', it started once the ECU adapted to the intake boot & K&N. Now, many hundreds of miles later, I can feel more power across the rev range, before 3000rpm there is noticeably more torque. However, the increased power above 5000rpm feels extremely significant, there is a noticeable and very strong pull within this rev range.

I'm yet to dyno the car since completing all mods, but I'm estimating the car to have between 290 and 300 bhp. Though I know someone who achieved 308 bhp with an injen intake system but with the secondary cats still in place.

[84Reasons]

Originally Posted by rnyassar

Hey guys,

I thought I'd weigh in on the situation. I've recently bought and fitted a 30i inlet too. Though I had my car mapped a few months ago without it. On the dyno with purely a stage 1 and a muffler delete, this is what my car achieved.

Attachment 2664058

I'm quite surprised that you achieved only 263.4HP with the inlet manifold.

After this dyno, I installed a Mishimoto silicone intake boot as well as a K&N air filter. I did not feel much gain, maybe a slight bump of power around 2500 rpm and 5500 rpm. After a few hundred miles, the car began to subtly burble on overrun. I noticed that the engine revved more freely too.

A month or so later, I removed the secondary cats. I could noticeably feel slightly more top end power, and at the lower/mid RPM, the car felt slightly more urgent. The burbles were now amplified 10x in volume. I then took the car on track to compare the top speeds.

With just a stage 1 and muffler, my speedo dial read 155 mph as a maximum, however, after these extra few mods (not incl. the 3 stage manifold), my speedo dial reached the limit, it was showing approximately 165 mph as an end stop - though I felt it was still increasing in speed.

After fitting the 3 stage inlet manifold, I allowed 100 miles for the ECU to adapt. I noticed after 30 miles, my burbles stopped - I'd like to point out that the car was never mapped to include 'pops & bangs', it started once the ECU adapted to the intake boot & K&N. Now, many hundreds of miles later, I can feel more power across the rev range, before 3000rpm there is noticeably more torque. However, the increased power above 5000rpm feels extremely significant, there is a noticeable and very strong pull within this rev range.

I'm yet to dyno the car since completing all mods, but I'm estimating the car to have between 290 and 300 bhp. Though I know someone who achieved 308 bhp with an injen intake system but with the secondary cats still in place.

In response to why the car only achieved 264hp - if you take a look at the dyno you will see it had lost quite a few HP since factory so starting point was around the 200 mark. If I was at the stock figures of 218 I could have perhaps made around the 280 mark total! When speaking to Garath as well he mentioned that it can be quite unpredictable with these cars - he had an n53 325i come in with a 3 stage manifold only producing 174hp without a map - after the map it was running 280! the gains are impressive there - not all cars react the same way.

I'm currently having an issue with an injector so the car is running awfully, having it replaced soon at the garage, perhaps the car was not running as it should even then due to the injector as I only had it mapped recently.

In terms of what you have done to yours, I'd be interested to know exactly where you got your part etc? obviously it's important to note that the HP could also be that all I have done is the manifold and map - no cat deletes or the like.
TO confirm you put a mishimoto intake boot on with k&N filter & deleted secondary cats? I may have to give this a go!

[rnyassar]

Originally Posted by 84Reasons

In response to why the car only achieved 264hp - if you take a look at the dyno you will see it had lost quite a few HP since factory so starting point was around the 200 mark. If I was at the stock figures of 218 I could have perhaps made around the 280 mark total! When speaking to Garath as well he mentioned that it can be quite unpredictable with these cars - he had an n53 325i come in with a 3 stage manifold only producing 174hp without a map - after the map it was running 280! the gains are impressive there - not all cars react the same way.

I'm currently having an issue with an injector so the car is running awfully, having it replaced soon at the garage, perhaps the car was not running as it should even then due to the injector as I only had it mapped recently.

In terms of what you have done to yours, I'd be interested to know exactly where you got your part etc? obviously it's important to note that the HP could also be that all I have done is the manifold and map - no cat deletes or the like.
TO confirm you put a mishimoto intake boot on with k&N filter & deleted secondary cats? I may have to give this a go!

I would guess that the injector is either leaking or has a dodgy spray pattern? I'd imagine the tuners you used would've heard knocking during the dyno if the injectors were causing an issue at the time.

In terms of maintenance, at 96k the car had new index 11 injectors fitted by BMW under warranty; at 100k I fitted a Noxem emulator to fix my low power and fuel economy problem; at about 102k, I had the following done: new coils, plugs, oil cooler gasket, oil filter housing gasket, new valve cover with gaskets + a full service (incl. gearbox and diff fluid). I did also inspect the inlet valves which looked reasonably clean. Put simply, I made sure the engine didn't have any weak points.

In terms of mods, I have a stage 1 tune from PSL Tuning, they tuned the car OTA while completely stock; I then got a muffler delete, purchased from Zaustworx, after which I had the car dyno'ed. The dyno was done after all of my preventative maintenance.

A few months later, I fitted the Mishimoto intake boot and K&N filter (I sourced these from eBay). After this, I had the secondary cats removed at Fastlane Styling and I managed to source the 30i inlet from an E61 LCI 530i, I fitted that with two new Febi DISA valves and new gaskets for anything taken apart. I'm now at 107k and the car feels the most powerful it ever has. Though its a shame that the very problem I solved with the Noxem has been brought back as a result of my mods

I thoroughly recommend my set up, the enjoyment driving is always at an all-time high! But beware, MPG becomes smiles per miles.

[84Reasons]

Originally Posted by rnyassar

I would guess that the injector is either leaking or has a dodgy spray pattern? I'd imagine the tuners you used would've heard knocking during the dyno if the injectors were causing an issue at the time.

In terms of maintenance, at 96k the car had new index 11 injectors fitted by BMW under warranty; at 100k I fitted a Noxem emulator to fix my low power and fuel economy problem; at about 102k, I had the following done: new coils, plugs, oil cooler gasket, oil filter housing gasket, new valve cover with gaskets + a full service (incl. gearbox and diff fluid). I did also inspect the inlet valves which looked reasonably clean. Put simply, I made sure the engine didn't have any weak points.

In terms of mods, I have a stage 1 tune from PSL Tuning, they tuned the car OTA while completely stock; I then got a muffler delete, purchased from Zaustworx, after which I had the car dyno'ed. The dyno was done after all of my preventative maintenance.

A few months later, I fitted the Mishimoto intake boot and K&N filter (I sourced these from eBay). After this, I had the secondary cats removed at Fastlane Styling and I managed to source the 30i inlet from an E61 LCI 530i, I fitted that with two new Febi DISA valves and new gaskets for anything taken apart. I'm now at 107k and the car feels the most powerful it ever has. Though its a shame that the very problem I solved with the Noxem has been brought back as a result of my mods

I thoroughly recommend my set up, the enjoyment driving is always at an all-time high! But beware, MPG becomes smiles per miles.

Yeah we're not sure yet as it had oil leaking into the cylinders which we fixed as we thought it was that however now injectors are suspected - lumpy idle and misfires at low rpm under load, fine at high rpm though.

Mines had new sparks and coils all round, new Nox sensor after it threw a code and general servicing at regular intervals. Almost at 50k. Sounds like yours is more bulletproof however.
The muffler delete from zaustworx is that straight through from the cats? What did it Dyno at stock?

I'll have a look on eBay for those bits however I feel as though most of the gains came from your secondary cat delete and back box delete? I want to do secondary cat delete however I read it doesn't pass MOT?

[rnyassar]

Originally Posted by 84Reasons

Yeah we're not sure yet as it had oil leaking into the cylinders which we fixed as we thought it was that however now injectors are suspected - lumpy idle and misfires at low rpm under load, fine at high rpm though.

Mines had new sparks and coils all round, new Nox sensor after it threw a code and general servicing at regular intervals. Almost at 50k. Sounds like yours is more bulletproof however.
The muffler delete from zaustworx is that straight through from the cats? What did it Dyno at stock?

I'll have a look on eBay for those bits however I feel as though most of the gains came from your secondary cat delete and back box delete? I want to do secondary cat delete however I read it doesn't pass MOT?

I would check your valve cover for any cracks, although the motor might only have 50k, the heat cycles on the plastic valve cover cause warping and this makes them prone to cracking.

The muffler delete is straight through after the resonator, if you check out their website, it was an off-the-shelf solution. Well the dyno was purely just a stage 1 with a muffler delete, the secondary cats were still present at the time. I never dyno'ed the car stock so I wouldn't be able to comment on the base figure. I can say that the previous owner drove the car very easily for approx. 55k miles over 8 years (mostly motorway). The majority of the gain is definitely due to the tune, my tune's curve is much more linear compared to yours, torque seems more consistent without any dips too. Whilst I do believe the secondary cats have helped with power, it is only marginal and the majority of the gain, if any, is top-end. When I had the car dyno'ed, the dyno operator noted that the linearity of the HP curve at the top end was due to the muffler delete. Though, as I say, I'm yet to dyno my car again with all current mods, I can only estimate by feel and in comparison to on-the-road testing, the inlet manifold definitely feels like it has significantly increased the power compared to my dyno figures. The car you mentioned before at Map-Tech made 286 bhp and 261 ft/lbs of torque with just the inlet and secondary cat delete, I should hopefully be slightly higher with my extra muffler delete and intake mods, I won't be retuning it with the inlet either until I see what power the car produces currently.

I do recommend the intake boot, the idea behind it is the more direct airflow, the stock intake boot has a large resonator box which is meant to silence intake noise but at a cost of direct airflow. I personally don't feel a K&N offers much benefit other than being a lifetime filter. I did install both at the same time so I can't comment on each individually.

With regards to removing the secondary cats, you should have no issues for MOT in terms of emissions; though depending on the MOT tester, it may fail for not having all factory fitted cats in place.

[84Reasons]

Originally Posted by rnyassar

I would check your valve cover for any cracks, although the motor might only have 50k, the heat cycles on the plastic valve cover cause warping and this makes them prone to cracking.

The muffler delete is straight through after the resonator, if you check out their website, it was an off-the-shelf solution. Well the dyno was purely just a stage 1 with a muffler delete, the secondary cats were still present at the time. I never dyno'ed the car stock so I wouldn't be able to comment on the base figure. I can say that the previous owner drove the car very easily for approx. 55k miles over 8 years (mostly motorway). The majority of the gain is definitely due to the tune, my tune's curve is much more linear compared to yours, torque seems more consistent without any dips too. Whilst I do believe the secondary cats have helped with power, it is only marginal and the majority of the gain, if any, is top-end. When I had the car dyno'ed, the dyno operator noted that the linearity of the HP curve at the top end was due to the muffler delete. Though, as I say, I'm yet to dyno my car again with all current mods, I can only estimate by feel and in comparison to on-the-road testing, the inlet manifold definitely feels like it has significantly increased the power compared to my dyno figures. The car you mentioned before at Map-Tech made 286 bhp and 261 ft/lbs of torque with just the inlet and secondary cat delete, I should hopefully be slightly higher with my extra muffler delete and intake mods, I won't be retuning it with the inlet either until I see what power the car produces currently.

I do recommend the intake boot, the idea behind it is the more direct airflow, the stock intake boot has a large resonator box which is meant to silence intake noise but at a cost of direct airflow. I personally don't feel a K&N offers much benefit other than being a lifetime filter. I did install both at the same time so I can't comment on each individually.

With regards to removing the secondary cats, you should have no issues for MOT in terms of emissions; though depending on the MOT tester, it may fail for not having all factory fitted cats in place.

I will mention that to the garage

Yep I thought it being less linear was due to the valves closing or opening at different points - maybe the mapper tweaked it differently?

I think I will try to focus on the intake boot and perhaps the back box delete but I do already have a smaller custom back box - however this was not done for performance.

[84Reasons]

Did a mod list recently if anyone is interested:
https://build.automodlist.com/HalsE93

Check the attachment for some photos of what the car is looking like now.

[rnyassar]

Originally Posted by 84Reasons

I will mention that to the garage

Yep I thought it being less linear was due to the valves closing or opening at different points - maybe the mapper tweaked it differently?

I think I will try to focus on the intake boot and perhaps the back box delete but I do already have a smaller custom back box - however this was not done for performance.

It should really have an increase in HP at ~3000, yours does, and then ~4500rpm when the valve opens? Looking at your dyno, the HP actually drops before it starts to increase at 4.5k. Did you check that the smaller DISA was operating correctly before fitting? Also, I don't know what my dyno will look like now since it was tuned without the 3 stage, but having seen lots of other dyno graphs, mine is always very linear whereas others all have the same shape as the stock curve so mine was definitely tuned differently.

A smaller custom backbox should already give less restriction? Good idea, the intake boot is definitely worth it.

[84Reasons]

Originally Posted by rnyassar

It should really have an increase in HP at ~3000, yours does, and then ~4500rpm when the valve opens? Looking at your dyno, the HP actually drops before it starts to increase at 4.5k. Did you check that the smaller DISA was operating correctly before fitting? Also, I don't know what my dyno will look like now since it was tuned without the 3 stage, but having seen lots of other dyno graphs, mine is always very linear whereas others all have the same shape as the stock curve so mine was definitely tuned differently.

A smaller custom backbox should already give less restriction? Good idea, the intake boot is definitely worth it.

That's interesting - I didn't check that either of them where working - one was bought new and the other came with the manifold when it was bought 2nd hand..that could be the issue and I may look at replacing them