Looking at getting another Boxster S, need advice on performance upgrades
 

Hello,

I'm looking into getting another 986 Boxster S after trading in my last 550 edition for a new 135i. Unfortunately BMW is a POS and the factory will never fix known problems so I am in the process of suing them for breach of contract. anyways...

I have been looking into getting another Boxster S and am amazed at how sharply they have come down in price. I am looking at a project car with main goal of making some kind of HP. The only thing that made me sell my last S was that the car is painfully slow in acceleration. In the corners it paradise, which at a max I would throw some wheels like DPE and some pss9's on.

I'm looking for a bare minimum of 350whp, and trying to decide what approach to take. Here's what I'm looking at for possible engine performance:

-Rebuild/ bore out block using LN engineering parts with ~12.5 CR pistons, cams, forged con rods, headers, intake, ipd plenum, exhaust, and head porting. I've never seen that amount of N/A work on a Boxster before, and am not sure what kind of power is possible with that setup, but with that amount of work I couldn't imagine it wouldn't make more power than a 3.6 x51 engine package. I would also do the reliability mods such as IMS retrofit and billet tensioner.


-Go FI with a custom turbo setup and built block with lower compression. it would be running about 14psi or so on the built block with a water-air intercooler similar to TPC. Not really considering TPC because they are charging 10k for a setup that can be built with better components for half the price. Its just a matter of finding an experienced tuner, and I don't mind traveling for a good tuner.

My budget is 35k with the car, and am looking for advice on what my best options are from those more experienced in modding the my96 engine than I am.

The first time I laid eyes on the 135i I thought it was an underpowered dog. Sorry to hear yours really was a bad drive. I do love my 550i though. Very well built car and freakishly quick for a big sedan.

If I only had 35k for a motor-modded boxster, I'd probably buy a 2003 roller (for the rear glass window) and put a Subaru WRX or an LS1 in it... a race prepared (which is what you are describing) Porsche motor is $$$$$$.

Good luck on your lawsuit with BMW. I'd love to know if you got any traction with it.

Thanks for the reply.

I really would never consider a "bastard child" car with another manufactures motor. I can push the budget to 40k for the car, and I figure if I spend 15k on a 03-04 boxster s with high mileage, I couldn't imagine spending over 25k for the engine upgrades.

Rebuilding the motor

Nickies sleeving with JE pistons $4200
Custom billet connecting rods $1700
Head porting and polishing ~$1000
shaft regrinding ~$750?
Headers ~$1500
Exhaust $1000
Intake $400
IPD Plenum/ TB ~$1400
Fuel injectors ~$900
Billet tensioner $300
IMS retrofit ~$1000
Engine tuning ~$1500-2000

Total in parts is around 16k, and I have a great affordable Porsche specialist around that would do all that for 6-8k based on the work he's done for me/ people I know in the past

I'm considering doing the Flat 6 course and doing the work Myself. ( as long as you are systematic building an engine is not that difficult and I have a good friend whos been build high hp cars for 20+ years that could help)

If you want that kind of power, find a salvage motor out of a 997 S and tune it, but you might need bigger brakes, etc. 20k should do all that, motor suspension and brakes. good luck, keep us up to date on what you do. thanks

How much is a 997s engine and electronics? As far as brakes, i would do pads and brake fluid, which seems to be very effective on the forum it seems?

Yeah, unless you're doing some serious tracking of the car (i.e. full cage), good fluid and pads should be plenty. I really don't see how it's possible to overwork Big Reds on the street with good pads as long as you're driving at least a little responsibly.

Softronic would have the program to update your dme for the conversion for around 1300. Engines its seems lately are harder to find because so many have done the conversion allready they used to be around 10k last one I found was around 15k you have to shop around. this is what I want to do to my car but I dont have the time right now. Another choice is to turbo, it's relatavely safe because they are running only 5 psi boost but make around 365RWHP , currently I'm working on a kit for around 6500 it's still in the funding phase.
good luck, keep us posted.

rc:

Sounds like quite a project underway. Let us know which way you go.

Curious as to what the specific shortcomings of the 135i are. My GF has been talking about getting one and I'd like to talk her out of it. :confused:

Regards, Maurice.

My LN sleeved 3.8 hauls &@*, and should be plenty more reliable than a stock M97 3.8, and makes more power.

If you start with a 3.6 you do not need injectors.

I am currently running RoW 3.6 X51 software, but am planning a tune, probably by EPL in the spring. Over the winter, the car may be getting solid lifters and "race" cams.

I would NOT go the turbo route on anything but a built engine.

My car has been in the shop for over 60 days for various problems. The waste-gates on the car rattle, the windows automatically go down when you try to put them up, the ipod cable has gone bad three times, the car drinks a quart of oil ever 5k miles, the airbag on the passenger side is raising on the dash, the side markers filled up with water when it rained, one of the coils went bad, one of the DI injectors went bad, and numerous other things. The car has been an absolute nightmare to say the least

rc:

Whoah! That's quite a list...thanks for sharing the info...can't wait to show it to the GF! :matchup:

Looking forward to seeing which way your project goes.

Regards, Maurice.

Then you can afford my 4 liter engine making 450HP. I know where all sorts of Boxsters are with blown engines...

As usual I vote for Jake's solutions.

Yeah, I thinking a built block is better than an engine swap at the moment, but I am not sure. Look forward to hearing your input.

OP: Are you part of this class action?

N54 Class Action

The fuel pump issue is well known by now. That's the only thing keeping me from buying a 335i as my daily driver.

Nah, I have a lawyer filing a federal lawsuit for breach of contract because of not honoring their warranty. Its similar to most lemon laws, but it has some advantages. I have a "software fix" for my hpfp. They said it would fix it but all it does is run the lpfp more to supplement the failing hpfp...

Flat6 engineering, I am very interested in this option. IS it feasible to have a 4 liter daily driven? Also, I would guess that the car would be a late model 986s because the block is different?

I'm not too picky on the car as long as its in good condition. Basically it would have to be a black or tan interior, have litronic headlights, and hopefully the bose sound. I like most colors except the burgandy and some off the rare colors.

If you could pm me some information on the rebuild it would be greatly appreciated.

rcracer_tx,

The 4 liter is not an engine that I have developed for street use, because it more than likely would not pass any emissions test and I'd rather not get into a situation where their is even a chance of that occurring. This is why an engine like this is sold to be utilized on the track.

I understand it is a track only engine, but I know plenty of people at the testing centers, and the car will more than likely be registered in Oklahoma where there is no emissions testing ;)

My question is hypothetically speaking, would it be reliable enough to drive like your were on the street for a long time, with the occasional track event such a Motor port Ranch. The car won't be driven all that much though maybe 50-100 miles a week.

I'm guessing Jake would rather not answer that question on an open forum, even hypothetically......though what you do with an engine after purchase is between you and your conscience.

Gotcha. We have no emissions here either. I have not developed this engine for the street due to emissions.

No problem. Its not developed to go 100K miles.