Project 996 Road Rallye: Part 10

The boys installed the new IMS bearing.  The generally accepted IMS service interval is to replace the IMS whenever you replace the clutch. This seems like a good plan though I would budget for this service immediately if I bought a used 996.  Gearbox removal is not as difficult as the 'box in a Lotus Elise so the cost is not really astronomical - unlike an engine replacement that may be required when the IMS bearing fails!

This IMS kit comes recommended by our friends at Slakker. I visited their shop a couple of weeks ago to learn more about their engine-building capabilities. They partner with Hartech in England for engine components, and they’ve invested in an in-house dyno to ensure every build is thoroughly vetted before installation. With Slakker as a trusted source for engines, we’re even more confident in servicing these cars.

Project 996 Road Rallye: Part 9

 

We bought an inexpensive short shift kit from eBay to test out on this car as the shifter was really sloppy.  The kit arrived and appeared to be nice but after installation, we noticed the lever was oddly positioned.  We had a 996.2 in the shop and compared the two saw that ours way off.  Further scrutiny revealed the the shifter came to us incorrectly assembled.  We took it apart and reinstalled it.  The forward gears all worked, though a bit shorter than I like.  The Reverse is hard to engage.  We are contacting the Supplier to see if we missed anything on the install.

We are attempting to find wheels that will be an inch smaller diameter - from 18" down to 17".  My plan is to increase the tire aspect ratio so we could gain some additional sidewall height for more compliance.  Originally I was planning on increasing the overall diameter of the tire but have now decided to stick closer to the original tire diameter.  Regardless we will gain some more compliance if I can fit a 17" rim.

The larger diameter Girodisc is making the 17" wheel a challenge.  We bought a wheel measurement tool that allows us to simulate the wheel diameter, width and offsets.  Now that we have the Elephant dampers installed, we broke out the tool to confirm clearance.

It appears that a 17" wheel can work at an offset of ET45 vs ET55 (stock).  We plan to go with a wider rim from 7.5" to 8"  as the tire will be 225.

We bought some new tires to install on the stock rims so we can test while we wait for the wheels to be sourced/secured.  Though they will lack some of the compliance I was hoping for, they should work well enough for us to see if the suspension needs to be retuned.  The Yokohama Advan Sport A/S+ is an all season ultra high performance tire that should deliver good road manners in the dry or wet.  The treadwear rating is fairly soft (440AA A) so we should have decent life with acceptable grip.  As a comparison, the Lotus run on tires with approx 200 tread wear rating!

Porsche 964 Refresh

We received a 1992 911 in for a mild refresh.  The owner loves the car and plans to keep it forever.  He wanted us to go through and identify anything that needed repair and address a few items that were bugging him.  The first was the ride quality.  His wife refuses to drive in the car as it is too rough.  Two things were obvious fixes: old tires and blown original dampers.  

The tires were an easy fix but first I attempted to convince the client to go with smaller wheels.  The car came to us with 18" rims vs stock 16".  The consumer market likes cars that have BIG wheels and are lowered.  This car was set up that way.  This owner does not track the car nor drive it overly aggressively.  So I am trying to convince him to consider stepping down to 17" rims to bring back some compliance to this car.

Since the car is not being tracked, we decided to install a set of the Bilstein PSS10s.  These dampers are pretty popular and considered a single adjustable with a clicker located at the base.  This makes them quite easy to adjust with 1-10 clicks.  1 = softest and 10 = hardest.  We are aligning the car with the RS spec ride height but with a stockish alignment.

We also took the opportunity to have the undercarraige dry ice cleaned as it was also nearly as nasty as our 996RR!  The corrosion that we found required a hard brake line replacement as the fitting was frozen.  We changed out all the rubber brake lines as they were original - 33years old!

Project 996 Road Rallye: Part 8

 IMS bearings are cited as a weak link of the 996 cars.  The market has punished their values significantly because of this issue.  These IMS failures, which will take out an engine, affects less than 10% of the cars.  We plan to offer this IMS replacement service as I feel the cars are great sportscars that can be had at a great value due this perceived, yet correctable, weakness,

We are testing out a rear chassis brace

Our car did not appear to have ever had an IMS change.  With over 100k miles on it, we decided to swap it out.  This also gave us a chance to inspect the Rear Main Seal and the clutch.

With the gearbox out you can see where the IMS resides.  We used a special puller tool to yank out the IMS bearing after setting the engine to top dead center.  This is not a job for a beginner as it requires some specialized tools and certainly some clear knowledge of these engines.

We inspected our bearing and found it was in good shape.  You can see it shown below with the seals off.  Ours was the dual row bearing that is known to be better than the single row.  You can also watch a bit of the removal and inspection process in our YouTube Video.

We have sourced a replacement bearing recommended to us that we will install soon.  The clutch and flywheel are worn so will get replaced when it all goes back together.  The rear Main Seal was not a source of any leaks but will get changed as it is old.

We are contemplating pulling the engine to fully inspect and clean it.  The dry ice cleaning took care of the underside but now that we can see the top of the gearnox and engine, the grime and gunk needs to be addressed!

Tomorrow we are hosting a Tech Seminar about this build at our shop.  You will be able to see all of these bits in person.  Come join us!

Project 996 Road Rallye: Part 7

We have been playing around with bumper ideas for this build. Most of the Safari-style tube bumpers are more aggressive that we want - and heavy. 

stock bumper is hidden behind the rear fascia

 Our goal is to create smaller bumpers that are effective and can support lights and tow straps. We decided to build some bumpers that would attach to the factory pistons that the internal bumper bolt to. 

The stock internal extruded Al bumpers are pretty cool.  The rear, shown above, has additional extrusions that attach to the rubber bumperettes that are visible on either side of the license plate.  The front is a bit simpler and shown on the left.  Both have threaded bungs for the factory towing loop.  The rear requires license plate removal to access it.

too big!

We tried several ideas and landed on small bumpers that I think should do the trick.  The front bumper attaches to the factory pistons and deletes the internal Al bumper.  The rear attaches to the bumperette mounts and is a bolt on solution that requires no permanent modification to the car.  Our tube is easily as strong and since it is external to the fascias, we should be able to take a bump or two without damage to the body.

We want to mount two driving lights from the bumper and hang a fabric tow strap.

The rear bumper will get a rear fog lamp and also a two strap.  The final design is still in the works but I think we are getting there...

Project 996 Road Rallye: Part 6

We installed the Girodisc 2-piece rotors as the car needed new brakes.  I wanted to save some weight if possible - which we have.  But I want to do down to 17" rims.  We bought a wheel measurement tool to better estimate what offset/width and diameter could possibly work.

GiroDisc weights: 

• Front: 17.95 lb each 
• Rear: 15.25 lb each 

Our stock rotors were worn so I searched for better weights.

OEM-equivalent weights (ours): 

• Stock front: ≈ 23.1 lb each (18.7lb)
• Stock rear: ≈ 14.6 lb each (12.55lb)

Weight deltas (per rotor → per axle → total) 

• Front: 23.1 − 17.95 = 5.15 lb saved per rotor → 10.30 lb per axle
• Percent change: 5.15 ÷ 23.1 ≈ 22.3% lighter per rotor 
•  Rear: 15.25 − 14.6 = 0.65 lb heavier per rotor → 1.30 lb per axle (heavier) 
•  Percent change: 0.65 ÷ 14.6 ≈ 4.5% heavier per rotor 
•  Net vehicle change (all four): −9.0 lb unsprung/rotational mass (mostly from the fronts). 

 What that means on the car The fronts deliver the big win: ~10.3 lb unsprung + rotating mass off the nose, plus larger diameter and better cooling. The rears end up roughly stock-like in weight (slightly up), which is normal for upsized rear rings on two-piece kits.  

Girodisc upsized their rotors vs the stock sizes.  Why?  The rear stock rotor houses a drum brake for the handbrake.  To clear this, Giro have to make their rotor larger.  They then enlarge the front as well to maintain the brake bias.  The benefit is larger brakes for more over heat capacity and performance.  So overall, a good tradeoff - lighter unsprung weight and more performance.

The wheel tool that we used suggests that a 17"x8" rim could work for us at the front.  This would be great as we would like to run tires with more sidewall.  Once the Elephant Racing dampers arrive, we can install and do a proper measurement.

Emira Collision Part 3

 We've received a few parts with this collision repair but many parts are still back ordered.  One key part that we have been waiting for was the rear box.  It arrived but the hardware to fully attached is still missing.

Lotus have this car in production so parts should not be so hard to secure.  They did have a massive layoff at the factory so it is possible Lotus Cars USA have been caught up in this financial cash crunch.  We've ordered parts directly from the UK as a result.  

Project 996 Road Rallye: Part 5

Clean - Dirty

 Cleaning the underside of the car was high on our list as it was pretty nasty.  The results are pretty impressive.  Dry ice is sprayed onto the parts that needed cleaning.  The operator varies the pressure and other variables to dial in the spray.  Supposedly this system can remove the ink from a business card - so can also work very gently.  

Our car had a fair amount of grime and grease built up.  Cleaning it all makes for an easier car to diagnose (leaks) and for a tidier disassembly and reassembly.  Since the suspension and brakes are all coming out, along with the gearbox and possibly the engine, it made sense to invest in the thorough cleaning.

Project 996 Road Rallye: Part 4

Wheels, Tires and Brakes are proving to be the biggest challenge in this build.  Since our goal is to create a car that will work 90% on broken pavement and 10% groomed dirt roads, we are sticking with tire sizes that favor the road.  But we are looking to add compliance through larger side walls as well overall larger diameter to gain some ground clearance.  

Most of the Safari builds run the same size wheel and tire on all four corners and the fifth which they keep as the spare.  On dirt, this can work, as grip is usually minimal.  But our car is going to run on the road so tire size will defer to weight bias.  We wrote about tire selection on a previous Blog: HERE  Since these are rear biased cars, larger tires are needed at the rear.  We will follow what is typically used for the road cars with more sidewall.  Plus our tire should be quieter than one that favors dirt.

We started with tires and then are attempting to find rims that will fit.  I used a resource on the web that will compare wheel/tire sizes and visually shows the potential impact.  The rear option is shown below.  I linked the image to the website.

We have contacted several of our favorite wheel suppliers including: Braid, HRE, BBS and TireRack to see what options we can find.  Ultimately determing clearance with the new Elephant Racing suspension will be key.  We have a tool that should help us make that determination on rim width and offset.  We will post up pix of this tool in action when we get to this stage.

One of my friends, who is Ride & Handling engineer at Toyota, and races 911s, has suggested the Conti Extreme Contact Sport 2 tires.  These seem like a great solution that come in the sizes that I am after: 225/50R17 front and 285/40R17.  

The Girodisc brakes that we have ordered are slightly larger in diameter than stock.  This is due to the fact that  the 996 has a rear (in hat) drum brake for the handbrake.  Giro needed to make the rotor larger to clear the drum and up sized the front to match the rear  - to keep brake bias the same as stock.

We ordered their caliper rebuild kit as well since these have over 100k miles on them.  We will vapor blast the calipers and replace the seals and rubber boots.  New Stainless Steel brake lines are ordered as well as 25 yr old rubber lines don't instill confidence!

We are hosting a Tech Seminar on Nov 8th to show off the build.  We plan to have the tire/wheels selected and have the brakes installed by then.

IMS and engine upgrades related to reliability are also on deck once the car returns from dry-ice cleaning of the under-carriage and suspension area.

Project 996 Road Rallye: Part 3

We've decided to have some fun with the car while in the build phase.  My other company, BrandXTR, is a local marketing company that is also a 3M Preffered Installer - so vehicle graphics are in our wheel house.  We have plenty of scrap film that we can slap onto the car to give it a unique look while we work on the important bits.  We plan to remove these graphics once the car is finished mechanically and is ready for cosmetics.  We will be designing a new livery for the car that will be more sedate...

I was inspired by a Brumos Porsche graphic and decided to take some creative liberties.  We chose a medium blue metallic film and a white CF-look film.  Dave got to work and installed the film.  Some of the tools that are available now are pretty cool.  The knife-less tape that he used to cut the edge was really handy.  Dave was certified by 3M after attending their workshop years ago so is very qualified to do these installs.  He was able to apply the stripes across the rear wing/vents and results are pretty amazing - even for a temporary stripe!

We created a new logo for the 996RR so decided to apply it to the sides.

We figured this would be a fun graphic on the side that is sure to elicit questions!

Project 996 Road Rallye: Part 2

The car is in rough cosmetic condition.  It needs quite a bit of things inside and out.  The old window tint was bad and the windshield was cracked.  We got those sorted as we waited for additional parts that we ordered from Elephant and Girodisc.

We pulled the front and rear fascias off the car.  This gave us a peek at what we would secure tube bumpers to.  Our fabricator, Danny, came by to assess the possibilities.  We plan to create a fair discrete bumper that will allow us to hang driving lights while also providing some protection from parallel parking.

Overall the car appears to be in decent mechanical condition. There appears to be an oil leak coming from the engine that we will need to investigate. We have the car scheduled for a dry ice cleaning of the underbody.

While under the car, we noticed some opportunities for improvements.  Expect some new ideas from us soon.

The front facia was pretty bad and I managed to find a good used one along with a front DS fender.  The front headlights have washer nozzels - one of which is broken.  We are deleting these along with the pumps and associated hoses.  That'll save a bit a weight.

Wheel and tire considerations are proving to be a bigger challenge.  The suspension will sit 1" higher and ideally we would like to go with taller sidewalls.  We are working closing with Paul at Braid USA on solutions.  Two wheels I like include the Rallycross and the Dakar.