Herbmiester

This is my 335i on Tein S Tech Springs Koni adjustable and M3 arms front and rear. The front setup uses E30 Top Hats to raise the ride height as the S Tech springs are quite low. The rear uses 10mm hard rubber spacers in the spring cavities. Suspension is firm but surprisingly its not harsh and is daily drivable, and I live where the roads are crap. The M3 control arm conversion reduces the intial understeer noticeably and all but eliminates it at medium speeds and up. Turn in is very positive and precise.

A faulty solenoid in the mechatronis unit is not uncommon. BTW you have a ZF 6hp trans which is a very common unit so will not likely be any challenge for a good trans shop.

Btw you are welcome to drive my 335i with Konis and Tein S tech springs, pretty firm.

Yep have to agree with Olaf I think B4s are a slightly retrograde step.

Yes Jon is very good, real professional.

Yes 335i's will do that especially when tuned.

Very nice looking Touring.

Becomes very quick with a tune.

I bought DCIs and pipes off Amazon. Ditched the DCIs no improvemnt.

Stock 135i Front: 120 lb/in Rear : 350 lb/in e90 ZSP or e92 Front: 145 lb/in Rear: 460 lb/in e90/e92 BMW Performance (Calculated given that the material of this spring is the same as the ZSP springs) Front: 195 lb/in Rear: 505 lb/in M3 Front: 160 lb/in Rear: 550 lb/in Aftermarket KW v1-v3 (non M3) Front: 190-256 lb/in (progressive average) Rear: 545-570 lb/in (progressive average) KW Street Comfort Front: 286 lb/in Rear: 572 lb/in KW Clubsport (non M3) Front: 400 lb/in Rear: 570 lb/in M3 KW v3 Front: 285 lb/in Rear: 630 lb/in M3 KW Clubsport Front: 508 lb/in Rear: 800 lb/in Bilstein PSS10 Front: 385 lb/in Rear: 615 lb/in Eibach Pro-kit Front: 148 lb/in Rear: 456 lb/in Eibach Multi-Pro-R1 Front: 200 lb/in Rear: 500 lb/in Eibach Pro Street S Front: 134 - 271 lb/in (Progressive) Rear: 456 lb/in (Linear) HKS Hypermax Front: 448 lb/in Rear: 504 lb/in Tein Stech Front: 191 lb/in Rear: 593 lb/in Tein Euro Damper System Front: 280 lb/in Rear: 392 lb/in Tein ss-p Front: 392 lb/in Rear: 671 lb/in JIC-Magic Cross Front: 450 lb/in Rear: 674 lb/in TC Kline Coils Front: 350 lb/in Rear: 700 lb/in HP Autowerks Coilover System Front: Custom Tailored 300-500 lb/in (Contact HP Autowerks) Rear: Custom Tailored 500-1000 lb/in (Contact HP Autowerks) __________________

Looks like 16mm difference, 17mm was pretty close.

My buddy Boytie has one and we fitted a new intercooler and gave it an MHD stage 1 tune. I have driven it a few times and its pretty rapid. Its a really nice cockpit and that ZF8HP box is a thing of joy. Much more HP than it has now could be a bit dangerous. On the twisties its really a lot of fun, one of the most enjoyable cars I have ever driven.

Why dont you just send Bilstein an email then. I read the difference in an E90 between M sport and standard is 17mm.

If you are going B4 then yes this is the way to go but its just stock replacement twin tube shocks, . I think you are over complicating the B8, B6 thing. M Sport springs B6, simple.

Bilstein make it pretty clear that the B8 is for lowered springs like Eibach H&R etc while the B^ is for stock springs inc the M sport springs.

Kashish this is very good advice from a guy who pushed his N55 pretty hard and broke it.

Good plan, FWIW I am taking my Tein S Techs out and going back to M Sport springs. Well I think I will

Yes thats the one. Do it.

Drive a few first and check how they feel. I have added roughly 100hp to my 335i and Its quick, but HP is addictive and you may want more, but you may be happy with what you get stock.

M3 control arms; Best advice I can give you.

Having used Poly bushes on a few cars now I dont believe there is that much of a trade off on NVH, but it depends on how many bushes you replace, where they are fitted etc. Personally Running an E92 on standard tyres (not runflats) with M3 control arms (Stiff bushes) the ride is probably better. I dont think you can apply blanket generalizations like poly for race rubber for road. and considering you do a bit of motorsport in your I cant see the problem.

For my Koni rear shocks I dialed in more rebound damping, approximately 3/4 towards full firm. This works at motorway speeds but is a but crashy around the rough roads in the Valley. I have Tein springs which are progressive and firmer than M/Sport. Reasonably happy but not sure its any better than linear but slightly softer Eibach's or H&R's. If I did it again I would probably go Bilstein B8 if staying with lowered springs of B6s if staying with factory M sport springs. The Bilstein monotube design is superior to a twin tube setup but there are other factors like quality of manufacture and as mentioned damping vs spring rate. Koni adjustability will allow you to get those two things right for your application. All that being said I had some Koni Strt (orange) on one of my old E36's with some King springs (They were on the car when I bought it) and the setup was really good.

as was mentioned 500hp is an arbitrary number, what you are better looking at is what mods do you need to support a nice power increase while not shortening the life of your engine. MHD would be mu choice and if you went IC, Cat-less DP, Charge pipe, airbox/filter and an MHD stage 2+ tune you will get to around 420hp. If you want 500 then its a new turbo and exhaust and perhaps a modded inlet system. That said the N55 is not as strong internally as the N54 so you may be approaching the limits of reliable HP. You will also need an LSD as even with stock HP grip is an issues and with a tune and bolt on's the massive increase in torque makes getting two tires hooking up difficult. Where the n55 seems to work best is with mild to medium increases in power.

M Suspension is essentially just control arms and shocks. Yes there are other parts like the sway bars but if you just did the M3 front end you would get big bang for your buck and that is a whole truck load cheaper than an M3. Shocks are consumables, replace every 80k or so. I used Koni yellows with M sport springs and they work fine. You can adjust the rebound of course so that allows you to get a pretty close match. That said Bilstein and Eibach kits seem pretty well matched according to the US forums and I did read a post by someone at Bilstein talking about how the Eibach/Bilstein kits are matched. What changes is when you add an LSD then you can play with the rear sway bar diameter because you will be getting you power down more effectively.

I think I would have to sell my house to buy that engine.