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Mods and upgrades explained - Very Long!!

335K views 422 replies 178 participants last post by  Mpowered1 
#1 ·
Hey

A lot of people on the fest ask what mods are best for their bimmer so i thought i would list the most popular ones and describe why they are good for your bimmer. Will put them in order you should do them too.

These include engine performance mods as well as stability etc

This is just my view but will try to be as accurate as possible. Am sure MANY of you will disagree with some of the things that i say, but that is the beauty of a forum. These are compiled from my experiences as a racing driver, test driver as well as an avid Bimmerfest member

1 - Decent petrol
People often go and spend HUGE amounts of money on enhancements or their cars and then use rubbish fuel. E36's are fitted with 'knock sensors' which will advance and retard your timing to sure different octane fuels. The higher the octane of the fuel, the higher the flash point. You want to make sure that the fuel is being ignited in the cylinder at the right time and not any where else. I recommendV-Power 98 RON or at least the highest octane car fuel you can find in your area (US octane ratings work a little different. Not only will you get more power and a more drivable car, but your engine will be cleaner and you also get better MPG.​

2 - Good Spark Plugs
Ok, so you have you good petrol being sprayed into your cylinders, now you need to make sure there is a good spark. The OEM plugs are great but improvements can be made for a small cost.​
The best plugs out there are NGK IRIDIUM IX plugs. They are brilliant and the affects can be felt right away. The car is smother through the rev-range and pulls better at low revs. They are cheap too and should only set you back around 35GBP ($70).​
DONT go for Platinums as they are very problematic and can cause some very strange engine issues. Iridium has a massive melting point and so the electrode gap stays the same no matter how hot or how hard you push your car​

3 - Decent Tyres
So often people spend loads of money on upgrades and then put crap tyres on their cars. Remember, your tyres are the only things connecting your car and power to the road and so decent tyres are an absolute must! Tyres are very personal and need to suit your driving style. I always run Pirelli P6000's on my cars as they are perfect for normal driving as well as when i push it. If you want them to last a long time but dont need massive amounts of grip then a hard compound like Bridgestone. If you want lots of grip but dont mind replacing them often then a soft compound like Yokohama is the way to go. There are of course tonnes of others out there!!​

4 - CAI (Cold Air Intake)
The most common upgrade for the E36 (and most cars for that matter) is a CAI. A CAI allows cooler, denser air into your engine. Dense air contains more oxygen and the more oxygen you have, the better the bang in your engine leading to more power. The stock airbox on a bimmer is very restrictive and so does not let in the maximum amount of air into your intake. A CAI is a cone filter (such as K&N) with a metal heatshield that replaces the plastic air-box. The heatshield creates a cold pocket of air around the filter that blocks a lot of the heat of the engine. The result is a more powerful (up to 10BHP) and smother engine that also sounds amazing. A good CAI will cost around 150 GBP ($300) but you could get the cone filter without the heatshield for 60GBP ($120) and will still see big gains due to the increased air flow. I recommend K&N​

5 - Brakes
Ok, so you have more power by adding the bits above, now you need to stop the flipping thing. An E36 weighs around 1.5 tonnes and so you need some decent brakes to stop it. The OEM brakes are ok but if you need to stop from a high speed in a hurry then you are going to get 'brake fade'. Brake fade is the sporn of all evil and occurs when your brakes get hot. The pedal goes hard and your braking efficiency is massively reduced. You need to install cross drilled discs (rotors) to dissipate the heat caused by the friction as well as some uprated pads. I recommend EBC Green stuffs pads for normal to spirited driving or EBC Red stuffs ceramic pads if you like to really push it or do track days. The increased braking is amazing and brake fade is almost completely eliminated. To get rid of it, you will need to install braided hoses. When your brakes get VERY hot, your brake fluid boils and the standard pipes expand losing efficiency. The uprated discs (rotors) should also stop 'warping' which can be VERY nasty​

6 - ECU re-map/chip upgrade
All cars that roll off the production line have to conform to emissions and country laws. They are also made to allow for the worst fuel, the worst drivers, bad servicing and bad weather conditions. Although the ECU is adaptive and so will advance/retard the ignition timing as described above, there is still plenty of power locked away behind your ECU maps. An ECU remap done via your OBC port or a physical replacement of your chip modifies the map to the most efficient possible. This give you lots more power throughout the rev-band and increased MPG as the engine is working at it's best. NEVER EVER EVER add cheap devices that claim to trick the ECU into thinking the air is colder. These are a con, plain and simple. Always go for a well known, reputable companies product. Your ECU is your car's brain and you should never short change it. You would not go to back alley doctor for brain surgery and the same goes for your bimmer. Price is anywhere from 100-300GBP ($200-$600)​

7 - Performance exhaust
After fitting the CAI, you will have increased airflow into your engine and it needs to get out. OEM exhausts are restrictive like the intake and so a decent cat-back exhaust will give you more power gains and a lovely sound too. There are many many brilliant companies out there that supply excellent systems for the E36 depending on what you want, what sound you like and how much you want to spend. Prices are anywhere from 100-500GBP ($200-$1000)​

8 - Strut Brace
Strut braces stiffen up the geometry of the front and rear suspension giving you a more positive turn in. Prices are around 50-150GBP ($100-$300)​

9 - Underdrive pulleys
Underdrive pulleys are smaller and lighter than the OEM ones and reduce the parasitic drag caused by running your alternator. Gains of around 6BHP can be seen with no ill affects to your electrical system. Prices are around 100GBP ($200)​

10 - Uprated Engine Bushes
Engine bushes hold your engine in place and the OEM ones can cause the engine to move under hard acceleration/braking and spirited cornering. This increases momentum and can destabilise the car. These stiffen up the engine and stop it moving around so much​

There are of course many more out there (including suspension upgrades) but these are the most common and the ones i have the most experience with.

Hope it helps

Pirate (Pete)
 
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#283 ·
Son, I am going to assume that you actually read that you actually read that thread, and that you genuinely haven't ever heard of google.

When you enter big bore throttle body into google, not even entering E36 this is the first thread that pops up: http://forums.bimmerforums.com/forum/showthread.php?t=234025
 
#284 ·
spending 700 bucks on a large bore throttle is just plain ludicrous unless you have a built race engine. VAC motorsports has a variety of them, the cheapest being a hair under 600 bucks.
 
#288 · (Edited)
what a interesting thread although one vital thing has been left off (unless i missed it), not a performance mod but the best supporting mod for any engine and that is junk the plastic water pump and thermostat housing! i found this out the hard way having bought my 328i from a mate who had not used it for 16 months, thermostat stuck and head went pop along with the radiator. i got a alloy thermostat housing from a popular parts store here in the UK which was very lucky as they not restocked them for 2 years and a cast metal waterpump which i may upgrade to the performance pump available in the US.

anyways i have a replacement engine to fit which will get the stainless headers my mate added and a decat pipe, the M50 manifold convertion is top of the list, got the manifold but not the throttle body or plumbing, engine will get full service with NKGs and i will get a CAI then im having it flash mapped at a dyno across from my work. i want 230-240bhp and by look of it its well in reach with whats been mentioned on this site. i will update when all is done.
 
#290 ·
looking for audio help on 97 318ti

I have a 1997 318ti hatchback with less than 50,000 original miles on it. I want to up grade the sound system and have done some research but need some questions answered. First off I have a basic cassette deck receiver with 10 speakers and an BMW stock amp mounted in the trunk on the driver side quarter panel wall under the side carpet. I have a Pioneer DHX3500U receiver, new. I have the adapter harness for the stock BMW receiver plug and the Pioneer. My situation is the rear speakers. They are playing at 50% at best. They pop and crack at half volume. Initially I wanted to replace the rears with some mid level aftermarkets, looking to spend around $150 or so. The stock speakers are 411/2" rounds. I have been told and have read that I can not just plug aftermarket speakers into the BMW harness and amp. That it will ruin the speakers. From what I have learned the BMW amp is not compatible with after market speakers. I am trying to confirm these things and I am also trying to find out if I can by pass BMW amp and use my MOSFET amp that is internally in my new Pioneer deck? Can I unplug the input and output on the amp and plug those two lines directly into each other and this would bypass amp. is this true? or is there a better way to do this? Have also been told I cant run the other 8 BMW speakers from the MOSFET amp in my Pioneer deck. That the BMW speakers will not work with any other amp than a BMW. So, is it possible to put new rear speakers in car without changing all 10 and also get around the stock amp? Long question, I know. What I thought was gonna be a great afternoon DIY project seems to be turning into a technical high skilled job. Any help, info, ideas welcomed.
Keep on Bimming
Paul Corazzo
 
#292 ·
I have a 1997 318ti hatchback with less than 50,000 original miles on it. I want to up grade the sound system and have done some research but need some questions answered. First off I have a basic cassette deck receiver with 10 speakers and an BMW stock amp mounted in the trunk on the driver side quarter panel wall under the side carpet. I have a Pioneer DHX3500U receiver, new. I have the adapter harness for the stock BMW receiver plug and the Pioneer. My situation is the rear speakers. They are playing at 50% at best. They pop and crack at half volume. Initially I wanted to replace the rears with some mid level aftermarkets, looking to spend around $150 or so. The stock speakers are 411/2" rounds. I have been told and have read that I can not just plug aftermarket speakers into the BMW harness and amp. That it will ruin the speakers. From what I have learned the BMW amp is not compatible with after market speakers. I am trying to confirm these things and I am also trying to find out if I can by pass BMW amp and use my MOSFET amp that is internally in my new Pioneer deck? Can I unplug the input and output on the amp and plug those two lines directly into each other and this would bypass amp. is this true? or is there a better way to do this? Have also been told I cant run the other 8 BMW speakers from the MOSFET amp in my Pioneer deck. That the BMW speakers will not work with any other amp than a BMW. So, is it possible to put new rear speakers in car without changing all 10 and also get around the stock amp? Long question, I know. What I thought was gonna be a great afternoon DIY project seems to be turning into a technical high skilled job. Any help, info, ideas welcomed.
Keep on Bimming
Paul Corazzo
most of us run aftermarket speakers, and decks on the stock BMW amp. I myself have the stock BMW amp driving my shelf and door speakers which are all Kicker brand and then i have a separate amp that's bridged to run just a sub. it gets confusing but its all quite simple honestly
 
#291 · (Edited)
Ive never heard that about the stock amp


The only reason they arent plug and play is because the stock speakers have a harness that it plugs into where it then goes into the amp but you can easily just cut the connector off and splice the aftermarket speakers onto the wires and they will work just fine.

leave the stock amp alone unless you really have the time to decipher which wire is which
but imo the stock amp is really good
 
#295 ·
Upgrading Sound System

Today is my first day on the forum! Glad I joined, TONS of good info here.
I just recently updated my sound system. I have a 99 323i E36 Vert. Stock amp, stock speakers (10 speakers), aftermarket head unit. (The guy who put the head unit in got frustrated trying to hack into the stock system and only got the 2 speakers in the front kick panels to work. So I pulled the head unit and started over.) Here's my experience:
The stock speakers can only run from the stock amp as it has built in crossovers. If you try and run the stock speakers straight from an aftermarket head unit, you will not like the results, unless you are good at buying aftermarket crossovers and configuring them to the stock speakers. Just a pain.
Also, since the stock amp has built in crossovers, you will drive yourself nuts trying to figure out the wiring to make this work with aftermarket speakers. In addition, the stock amp is not 'adjustable' like aftermarket amps and again, you won't like the results.
It's just my opinion, but if you want a really nice system, just unhook (or remove) the stock amp and speakers and run all new. It's a bit of a DIY project but I did this and the results are AMAZING. Again, just my opinion, but the stock system is just not worth trying to hack into if you really want a nice system. If you shop around and Google for a while, you can do an entire new system for less than $800.
I bought a nice 6 channel amp and two sets of infinity Kappa separate component speakers with crossovers. One set for the front and one set for the rear. The amp and speakers were a total of $500. I also bought a 10 inch subwoofer (I went cheap here, for the time being) with a small enclosure for $100. The head unit the guy put in had pre-amp outputs for front, rear and sub. I ran all the RCA's to the trunk and ran all new speaker wires. Took me about 2 days of ripping the car apart and putting it all back together, but the results are WELL worth it.
 
#300 ·
Not trying to hate but where I'm from I think Tyres are spelt Tires. And smother is spelt smoother, always good to check spelling when doing a write up I think***8230;

Ok CAI***8230; This topic has frustrated me quite a bit. When it comes to these cars, I think if anything your CAI is going to be sucking in warmer air, as the factory box as a direct connection to the front of your grill. CAI's that go down below your engine are silly too because roads are usually really hot. I suppose if you have properly done a heat shield you might get back to the same air temperatures your OEM intake was getting. Secondly, Yes CAI's make your engine sound pretty beefy, and ya you'll get more air flow and more HP, but I really really think people should think hard (especially considering we are talking about old E36's, and parts aren't getting any easier to find) about what they value more, the life of their engine, and engine oil, or the 10 (at best) extra HP. I know cone air filter manufacturers love to advertise how their filters never need to be replaced and filter just as good as paper filters (if they are oiled, and who wants to constantly be oiling their filter) but you can't defy the laws of physics, they do not filter the air nearly as well as just a plain old paper filter. However I'm willing to consider that depending on where you live this might not be a big issue.

I enjoyed the rest of your write up, thanks for the post!
 
#325 ·
If we are going to be really fussy, the word you are looking for is spelt. How ever these really are not the worst of the grammatical errors in this otherwise awesome thread.
I think I have cramp in my face though as it took so long to read!
The info on the m50 mods has been really helpful. I'm not sure what engine I have (it's a 97 328I if anyone can help?) but I found that smoothing out and polishing the throttle body internals made a nice difference, and also completely removing the traction control unit altogether made a difference. It's not such a complex unit and as it works almost exactly like a reverse throttle body I thought that even when inactive it still creates a bit of air flow resistance. Also, if you remove it, it's one less part of the induction than needs to be cleaned.
I did find when I removed it however, you need to leave the connections attached as if you remove them the abs light shows on the dash.
Awesome thread though and thanks to everyone who contributed! I'm new to the site and I think I'll be using a lot of it!

Sent from BimmerApp mobile app
 
#304 ·
Hey, Im new to the forum but found this thread very helpful! My 98' 328i as been sittin for about a year with a bad trans, its an auto, but I am getting it back tomorrow! I have already gsthered many parts and have to diagnose a few problems when i get her back. One thing I wanted to do after completely redoing the cooling system and intake was a tune/chip. After talking with a mechanic he thought this to be a bad idea as my car has over 300k miles on it. He suggested first replacing the bottom end bearings, I have no issue taking the time but is it that big of a risk? The car has a strong engine that pulled strong only issues have been with the water pump breaking apart and typical suspension items being replaced.
 
#305 ·
Test the oil pressure. If it's good (~40psi) no need to rebuild. A tune isn't going to add THAT much horsepower. It's not like you're turbocharging it.

Welcome to the fest! Post pictures of your car. It's the law. ;)
 
#306 ·
Awesome thanks! As soon as i get my car back, hopefully tomorrow, I will post pictures. If i can find a willing soul I was considering documenting all the work Im going to do before making it a DD again. Im super anxious to get it back and start working on it again so I may accidently jump the gun before i can get a camera guy. But from what ive seen most of my projects already have a writeup so maybe i can just get greasy!:)
 
#311 ·
I have a 93 325is, I am planning on upgrading wheels and tires soon. I will be running ultimo coilovers. I want to know how wide i can go and what offset i would need. I want 10" wide in rear and at least 9" wide in front. I know I will have to atleast roll my fenders or alot of metal work on them which doesnt bother me. Im looking for maximum grip in corners. Will I absolutely have to run spacers going this wide? I would rather not use them.
 
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