School Project: 98 Boxster Rehab & EV Conversion
 

I am looking to order a complete kit of suspension parts to rehab all four on a 98 Boxster. Track arms, springs, struts, mounts - all need to be replaced.

In addition, I would like to be able to carry more (battery) weight as the next step is to replace the (very) tired gas engine with a high voltage DC motor. Objective is to out-perform a Tesla in as many metrics as possible; speed, accelration, range, cost.

So, job one at this stage of the re-hab is the suspension. Any ideas on an approach that won't break the bank? Any good kits out there that include all the necessary parts?

Well what kind of suspension do you want? Do you want a full on race suspension or a comfortable ride? Any way you go its not going to be cheap. The most basic coilover set that is worth looking at start at $2,000+. Also how much weight will the car gain with the added batteries and generator. You may want to make a custom set of springs and shocks to accommodate to your needs. But if you need to get some leads most of the people on the forum suggest going with the stock euro M30ROW suspension or the bilsteins PSS9 coilover kit. Stock suspension kit is around 1,100 plus shiping, and bilsteins are around $2,200. So those are some numbers. Hope that helps.

This doesn't include the control arms and other suspension components that have a huge range in price difference between stock and fully race ready parts.

FCP and Pelican parts are two good places to look for parts.

First, you need to calculate if there will be any change in total weight or location of that weight. If so, then you will need to take that into account when selecting suspension components. Until you know this, its very hard to make any worthwhile recommendations.

I think there was/is a shop in Florida doing Porsche EV conversions. Have you reached out to them?

BMod986, thstone & Perfectlap - thank you for your posts - very helpful. Our weight objectives are to maintain the central distribution of mass and to limit the total, to stock curb weight plus up to 250 lbs. This project is NOT intended for the race track so race-ready parts are not required - but wouldn't be refused if they were the right fit for purpose and budget.

Initial question remains: "Does anyone offer a complete kit that includes all parts necessary for a complete rehab? Struts, springs, track-arms, mounts, bearings, etc"

With weight and balance remaining the same (or close to it), then a stock refurb should be sufficient. The only "kits" that I have seen are here on our sponsor's site:

Porsche Boxster Suspension - Page 6

The kit includes:

• Control Arm Links (Front & Rear)
• Tie Rods (Inner & Outer)
• Tie Rod Boots
• Sway Bar Droplinks (Front & Rear)
• Sway Bar Bushings (Front & Rear)

You'll have to buy the struts and upper shock mounts (front and rear) separately but they are readily available.

There is also a nice DIY here: Pelican Technical Article: Front/Rear Boxster Suspension Overhaul - 986 / 987

Coil-over struts.
 

Thank you thstone for your very helpful reply. In replacing the struts, what happens to the original springs when a coil-over type strut is used as a replacement? Do they become surplussed?

Which strut replacement do you recommend to provide a slight increase in load capacity over the original equipment?

If you use a true "coil over" shock, then the stock spring and strut are thrown away. If you simply replace the struts, then the spring is re-used.

If you're only increasing weight by 250 lbs over stock, then I'd suggest replacing the struts with Bilstein Heavy Duty (which are equal to the upgraded M030 struts) and re-use the stock spings.

It has been suggested that the springs are worn out after 145,000 miles and need to be replaced. Do springs really wear out? If so, and if we don't want to lower the car, then what are the alternatives? I see a springs (for use in front or rear) on Pelican for $272 per pair. Is that likely to be the best alternative in terms of (1) being on a budget; (2) not lowering the vehicle; (3) being able to accomodate stock wieght plus 250lbs?

Separately, it has been observed that the rear brake lights flicker when the brake pedal is depressed rather than staying lit. Is the likely culprit the electrrical switch at the pedal?

Generally, springs should be fine for much more than 145K miles. Typically they are only replaced if they are broken, cracked, or significantly sagging.

Suspension rehab completed!
 

OK, the job is done! The students loved it.

We now have an Sir Tools B90-Porsche Rear Wheel Bearing R&R Kit that we bought for $515.98.

For sale for $300 or best offer. Used only once. Worked like a charm. Comes complete with SIR carrying case.

Please reply with any interest.

I suggest you post an ad in 'the parts for sale' section as it will be seen by more people. Also, can you tell us what you ended up installing on the car?