[jonwilli]

So I have been meaning to write a build thread for the 135i I bought nearly a year ago for some time. I thought now I'm doing some serious mods/refresh I should get around to it!

So the car is one of the last N54 135i's produced by BMW before they changed to the N55, build date December 2009. It is a Le Mans Blue 6 speed manual with a decent spec list; all important Xenon's, cruise control, heated manual black leather, Bluetooth, Professional CIC Navigation, rear PDC, voice control etc. The car is currently sat on 70,500 miles which isn't bad for its age and should go up slowly as I only drive it in the dry summer months as my E81 130i is my daily.

When I bought the car from Lee H a fellow forum member it had a fair few bolt on mods and is running about 400hp. It had the following:

BMW Performance exhaust and Y pipe
Evolve catless downpipes
VRSF 7" intercooler
HKS SSQV blow off valve
VRSF hard intake pipe
BMS dual cone intake
JB4 tuning box
BMW Performance front grilles
BMW Performance pedals
CDV delete
Reiger gloss black rear diffuser
Eibach Pro lowering springs
Rob Beck PCV valve
BMW Performance darkline rear lights

Some photos when I first got home with the car:

Since I bought the car I have added the following mods:

BMW Performance carbon spoiler
BMS short shift kit
Fitted my Apex EC-7s that were on my E81 130
Fitted an old AutoDAB kit I had and OEM DAB aerial
BMW Performance gear gaiter and Clubsport gear knob
BMW Performance hand brake cover
Mishimoto oil catch can
Quietest HKS blow off valve insert, original was a little too Fast and Furious for me!

Picture of the engine bay as it stands

Only photo of the exterior from end of last summer with the Apex wheels and BMWP spoiler...sorry its not the best photo!

 

[jonwilli]

Over the next month and whilst we still have Covid restrictions I have a boot full of parts to fit to the car. I have been collecting parts since last summer bit by bit as the suspension feels well past its best. It is much more noticeable on the 135i running high torque.

Koni yellow dampers, BMW Performance springs, H&R roll bars, Tyrants stage 2 camber plates, M3 steering rack, front and rear Meyle HD drop links, Meyle HD tie rods, M3 front arms, M3 rear arms, Powerflex Black subframe and diff bushes, Hardrace toe arms, diff brace, EBC yellow brake pads, F31 340i 370mm front calipers, Brembo discs and Goodridge braided hoses.

Refurbished rear subframe, 5 coats of POR15 and 5 coats of top coat...did the same on my 130i and hope I won't see any rust for many many years...fingers crossed!

I have brake fluid, oil and oil filter, hydraulic steering fluid and new coolant to service the car and keep maintenance up to scratch. Whilst I am fitting the M3 rack and ARBs I have a new thermostat and water pump to fit as I don't want this going when I am running higher power.

Today the diff was picked up by UPS for a Wavetrac to be fitted by MacG Racing a company one of our forum members, Willrace, works for. Whilst the diff is off I'll clean and treat the underside of the car with Bilt Hamber products to slow/minimise any corrosion. There are also plenty of undertray bolts and heat shield nuts that are pretty corroded which I will replace.

 

[wrevilo23]

I love reading your threads! Great post! I bet the car will be lovely...

 

[jonwilli]

I love reading your threads! Great post! I bet the car will be lovely...

Cheers :thumbs:.

I want to make it good as new, get rid of any slightly crusty nuts and bolts on the chassis and give it a full service overhaul and carry out any preventative maintenance this summer. It has had new Index 12 injectors a few years ago and being a late N54 there is no sign of wastegate rattle or any of the other usual N54 issues. I hope with a new water pump and thermostat I'll be ready to fit some Pure Stage 2 turbos in 2021. I want the chassis to be tight, stop well and get the power down before I do though. At the moment you can feel lots of slop in the rear suspension and subframe when you accelerate hard or go over certain imperfections on the road, which there are lots of down here!

 

[RoyBoy777]

As always Jon very impressed that a proper job is being done !! Always done right no corners cut. I look forward to following your progress on this one. Do you have a magic number you hope to reach when all is said and done.

 

[jonwilli]

Do you have a magic number you hope to reach when all is said and done.

No not really and I'm in no rush to up power in the short term. To be honest with the current engine mods the car is quick enough, the acceleration is really impressive! It is more because it is possible and on the table for not a lot of money! Pure say that their Stage 2 twin turbos can reach 540whp with just a LPFP swap, my current mods and 2" inlets on 98/99RON fuel. The same set up with meth injection will get 600whp. I probably can't be bothered with having to fill up meth regularly and lose the boot space plumbing it in. 540whp is a huge amount of power though, not far off 600hp crank!

I have considered a single turbo but it is more expensive, the power levels are even higher and the lag increases. All of which make it harder to enjoy even briefly on the road.

 

[jonwilli]

Last weekend I decided I would remove the rear subframe myself and swap in the new one on the drive. I was planning on getting a garage to fit for me mainly because of the almost guaranteed issue with corroded brake hard pipes. I have a spare OEM brake pipe set in really good condition for the subframe that I salvaged from one of the subframes I bought to refurb. My concern is the connection to the pipes that run from the engine bay to the rear. I eventually decided I would buy a flare tool and repair myself if needed...how hard can it be :shock:

Last night I removed the old subframe so the rear is now ready to strip all head shields off, clean and apply Hydrate 80 and Dynax.

Another update is I finished painting and lacquering the OEM 135i rear calipers and the 370/380mm F series calipers I bought second hand. I painted them Sparkling Graphite which is apparently the OEM code for the 135i calipers. The final colour is slightly darker than the OEM fronts but a very close match, the photos make them look darker than they are. I am really pleased with the finish they look very glossy and OEM.

 

[Nyxeris]

Calipers look great! Interested to hear how it goes with the subframe and brake lines too.

 

[THETYRANT]

Looking good Jon

 

[CalvinNismo]

What car did you get your donor rear subframe from? I've heard that the physical subframe is the same for petrol or diesel, even though the part numbers differ. There's loads of diesel ones around but not that many reasonable condition petrol ones.

Lovely car and lovely plans, you'll like the Wavetrac.

 

[jonwilli]

What car did you get your donor rear subframe from? I've heard that the physical subframe is the same for petrol or diesel, even though the part numbers differ. There's loads of diesel ones around but not that many reasonable condition petrol ones.

Lovely car and lovely plans, you'll like the Wavetrac.

All of the E8x and E9x subframes are the same. I bought both my donor subframes off eBay, just trawled for one with as little rust as possible. They're typically about £100 to £150 depending on condition and you can sell your old one for the same. I was lucky the second subframe I bought had somehow been covered by an oily tar. Not sure what it was and it was a pain to remove but had protected the paint from salt and water.

The subframe off this car will be up for sale in a few weeks. Its in pretty good condition. I've found despite the undertray screws being pretty corroded the chassis itself is in really good condition with little signs of rust.

I am looking forward to seeing how the E82 handles after the upgrades and refresh. Took my 130i down the coast early morning today for a blast (which has similar chassis mods) and the confidence and speed you can maintain around bends with the subframe properly tied down is awesome. Last time I drove the same road I was in the 135i and you could feel all the bushes moving and squirming and having removed them they weren't in bad shape!

 

[CalvinNismo]

All of the E8x and E9x subframes are the same. I bought both my donor subframes off eBay, just trawled for one with as little rust as possible. They're typically about £100 to £150 depending on condition and you can sell your old one for the same. I was lucky the second subframe I bought had somehow been covered by an oily tar. Not sure what it was and it was a pain to remove but had protected the paint from salt and water.

The subframe off this car will be up for sale in a few weeks. Its in pretty good condition. I've found despite the undertray screws being pretty corroded the chassis itself is in really good condition with little signs of rust.

I am looking forward to seeing how the E82 handles after the upgrades and refresh. Took my 130i down the coast early morning today for a blast (which has similar chassis mods) and the confidence and speed you can maintain around bends with the subframe properly tied down is awesome. Last time I drove the same road I was in the 135i and you could feel all the bushes moving and squirming and having removed them they weren't in bad shape!

I may be interested in taking it off your hands, if you haven't already got a seller lined up.

I'm having a similar feeling. Accelerating midway through a sweeping corner, it feels almost like I have rear wheel steering now I have a diff' and mid-corner traction isn't as much of an issue.

 

[jonwilli]

As its raining today and I can't work on the car some thread updates, I am hoping I will finally have the car back on the road in the next week or two...just for the end of summer . Anyway it has been a good project for a Covid summer where going out and about hasn't been easy.

Exhaust, diff, whole rear subframe and heatshields removed. This photo is after washing and degreasing all the metal. Rust patches are mainly where the heatshields are bolted to the main body. The heatshields are sharp and minor vibration over 10 years removed paint and allowed minor rust to form. When I refit the heatshields I put 30mm Stainless Steel washers between the body and the heatshield.

From memory four coats of Hydrate 80 to all metal surfaces

Three coats of POR15 topcoat

All metal surfaces sprayed with Bilt Hamber Dynax spray, heat shields back in place with Stainless Steel washers and Goodridge stainless steel braided brake hoses ready for the subframe to be fitted back in place.

 

[jonwilli]

Subframe fully poly bushed with Powerflex Black Series. I have the same bushes on my E81 and find them fine for the road and make a huge improvement to handling. H&R rear ARB and differential brace fitted to the subframe.

 

[jonwilli]

Subframe fitted which was a fairly slow process working on my own with a couple of jacks, some carpet and timber wrapped in bubble wrap! I wanted to make sure than none of the work to the underside of the car and subframe was damaged. It went very smoothly, just had to take it slowly and keep running around checking where every part of the subframe was in relation to the mounting points.

 

[jonwilli]

Koni rear dampers with Koni bump stops and Dinan 10mm top mounts. BMW Performance springs, M3 arms, Hardrace adjustable toe arms and ECS trailing arms. Meyle HD drop links and Goodridge braided brake hoses. I also replaced every nut and bolt with nice shiny new ones. The old ones weren't as bad as they first looked but thought it would make future maintenance easier and look better with the fresh parts!

 

[jonwilli]

Front arches cleaned, degreased, four coats of Bilt Hamber Hydrate 80 and two coats of Dynax spray. I also replaced the metal brackets that hold the brake hose connections as they were pretty corroded. I painted them with POR 15 top coat before fitting so they last.

Koni front dampers, BMW Performance bump stops and springs matched with a set of TheTyannts excellent stage 2 camber plates

 

[jonwilli]

Less exciting but important preventative maintenance at 70k miles on the N54 and most BMWs, new Continental water pump, Behr thermostat and Febi Bilstein hose. Had a bit of a nightmare stripping one of the threads on the engine block so had to fit a helicoil. Luckily the thread that went was the easiest to get to with a drill and tap. A word of warning the torque specs on BMWtis are out of date for the new steel water pump bolts and water pump without the integrated rubber dampers. Torque for the new bolts should be 22Nm...I found out the hard way!

 

[jonwilli]

The M3 rack is fitted but need to connect the lines and fill with fluid.

Annoyingly I broke the steering column removing the old rack. Working on my own, with the lack of space with two turbos and their heat shields plus a UJ that hadn't been removed for 10 years I didn't manage to do it without over extending the steering column, once you do it is terminal.

Second hand replacements are only £20 on eBay but means removing steering wheel, airbag, steering squib, column covers...pretty much everything. A little job remaining is to refit the gasket between the cabin and engine bay the steering column passes through. Can see this being a job that removes a lot of skin, results in a lot of cursing and may take several hours for what would be a 5 min job in less cramped environments!

 

[Poormans]

Rear suspension area looks mint!