HiWind

what are the odds hey .. reminds me of this ... bird flew into the car and hit the cutoff switch! The smudge and feathers led the marshall to the cause.

cobalt

A lot has happened and changes still to be made.

I spent two days at Watkins Glen two weeks ago. NNJR advanced event is always fun with 5 - 45min run sessions per day. Had the pleasure of Dave Scott pro driver (aka Voloce Raptor) sit in my passenger seat for two sessions. Apparently I was harder on myself than I should be. He had less criticism of my driving than I do. A bit more power here and less brake there and the car became so much more settled. Not unlike skiing where at times going faster is less work than going slower.

It is a great feeling when the LSD hooks up and the power can be put down much earlier and the car grips much better. The added power seems so much less intimidating than it did before.

Unfortunately my ABS pump has clearly crapped out so a change is needed but the car has more than enough brakes to do their job. The problem is as you use the brakes more and more the pedal has a tendency to drop a bit. I was hard on myself for not being able to rev match as the event went on. What I didn't take into consideration was what was really happening is as the pedal required more throw to brake my pedals no longer lined up for that easy rev match I started out with. I learned to compensate for it and it did improve but fixing the ABS pump is priority one and will eliminate the problem.

So as I used more of the throttle and track I was able to pick up the pace in the turns. By the second day many of the cars that were passing me I was now passing or they had to work harder to get by.

I am considering going with an electric power steering pump as the amount of work it takes to muscle the car around turns like carousel when starting out off line is considerable. Especially when running 45 min at a time with a 45 min break. The beauty of these cars is you have no doubt how fast you are going and speed is apparent unlike driving my BGTS at speed on track which seems like a walk in the park compared. I can only imagine how a GT4 or GT3RS feels with PDK which no doubt don't require all of the driver input and awareness to go just as fast.

Overall the car did quite well. It is a bit squirrelly in the rear and it has been suggested i need to add a minor amount of toe in at the rear to help with that. Several people had mentioned that they noticed it doing some odd things going into the bus stop.

So overall I am begining to get used to the car and have no doubt it will be a lot of fun and quite quick once I get everything sorted.

While I was at the event I was lucky enough to meet the new owner of Geoffrey Ring's RSR build. It inspired mine but was more than I wanted to do. My vision was to keep this closer to the original RS/RSR in power to weight and suspension. No doubt that will change over time.

So overall times were relatively consistent by the second day running between 2:19 and 2:22's. No doubt i can do much better but all in time and only once my ABS and suspension is finally sorted out.

cobalt

So speaking of power to weight. When I first started this build I found out how crazy the cost was to build a 3.8 RSR motor that puts out 350 to 385 BHP. I ended up sourcing the 993 engine with twin turbo setup and I know it was built for longevity vs power. My gearing allows me a top end of around 170MPH. Which i doubt I will ever see at least at the power the car is putting down but the 6 speed box which is not true to a 964 has me using mostly 4,5 & 6 gears with the occasional 3rd in traffic.

So I had the opportunity to dyno my car on a mustang dyno the other day. The car has more than enough power and although I still waiting on all the files it put down 336 RWHP on the best run. Don't have those charts yet

Roughly 400BHP a bit more than an RSR but my car also weighs a little more so power to weight is probably close. Besides add me and that really slows the car down.

We tested a bunch of cars including a 993 with Vram. I have a bad photo of the Vram against a 964 and then my Track car against the 964. The mustang dyno is as they say a heart breaker. It shows the numbers as they are unlike the results i find out of most Dynapack or Dynapro's that have a tendency to be a bit more optimistic.

As you can see by the poor photo the Vram 993 engine does give the car a bit more power up high over the 964 but not that much. Adding the TT setup to the 993 engine with 0.5 bar boost really adds power to where you use it on track. What is really impressive is the torque which humbles you a bit but once used to it is a wonderful thing.

Over 120 more hp and torque to the wheels and hundreds of pounds less weight is quite noticeable and requires a bit more respect especially with these older cars.

I have no doubt I can up the power to well into the 500hp range but I see no need at this point.

BTW disregard the AFR's we did not use an O2 sensor on these runs.

First picture is the 964 solid line vs the 993Vram dotted then the 964 the track car and the track car and 964 together. As you can see what i was used to drive and what I drive now are a bit different.

No doubts changes will be made over the winter but this is half the fun of building a car like this.

I estimate the power to weight to be roughly 6.2 pounds per hp which is more than enough to get into trouble.

cobalt

I also lost one of my front ducts so i picked up the cult werks parts. Nice pieces although require bumper removal to install properly.

Was trying to decide if I should go black or have them painted Blue to match the car.

Crappy pics I know but the cult werks pieces are more true to the factory parts and are of nice quality. If I go black I am thinking I need to paint the headlight trim rings black as well. Leaning towards painting them blue.

Hard to tell from the pictures but what do you guys think?

Ken D

Blue.

Richard H

Blue

cobalt

Dropping them off Monday to be painted blue.

FlyinTomato

black because race car.

cobalt

This will be continued on a new thread.

Remo85

Dear Anthony / Cobalt

Very very impressive project! Thanks for sharing all this project steps. The outcome is really stunning!

I'm also planning a widebody conversion. The plan is, that I will do everything with factory parts. Unfortunately, I have also a '90 coupe, so I will have similar issues during the conversion you had. So be it, nothing much I can do about that.
But there was one thing which wasn't clear in this thread, maybe you can help me. According to your pictures, you've changed the rear-end trailing arms from the narrow body ones to the turbo ones. Did you had any issues with that on the '90 version with the old rear chassis? According to the spare parts manual, there is only one version of narrow body trailing arms available. So if narrow body trailing arms didn't changed during the production years, the turbo trailing arms should also fit to the '90 production year? Are my assumptions true?

Thanks for your support in advance!

cobalt

That is a very good question. I actually swapped out the ams that were on the car with another set I picked up on ebay which came off a parted out RSA which already had all the spring plate and solid bushing upgrades done. It cost me less for the pair than half a set of ERP bushings. Just can't get deals like that anymore. .

So my build has the narrow trailing arms. IMO this is the best setup for these cars. The turbo arms are heavy and slower at responding and limit wheel width. I am using the turbo front outboard settings and the narrow rear arms with wider wheels. I have been under a 90, 91,92 cup car and my 93 this week. I do believe the RS had different bushings in the arms since it is essentially a RoW RS but would need to verify that. Although I don't see any variations of significance between them..

The rocker indents aren't an issue if you address them before paint. I should have dry fit mine first but it wasn't on my radar.

GL with your project.

BTW a new updated twin turbo engine is in the works hopefully will be done by early spring but I have been saying that for 2 years now. The Slick top and other projects have taken up all my time.

Remo85

Thanks for your answer and your support on this. I agree, that the narrow body trailing arms will have some nice advantages. But they also come with a negative impact on the bearings, if you're running wheels with a very low / negative offset. But I understand, for a track car which is anyhow extensively used, this is probably a minor disadvantage. It always depends on the use of the car. As I live in Europe, where regulations are more strict, I anyhow cannot increase engine power etc. So I will try to get as close a possible to the 964 Jubilé version.

So but if you're running narrow body trailing arms, the only thing I can do is try and error. I will write down if the turbo trailing arms fit (once I'm at that stage with my project). So if I have a '90s coupe. What else will make me headache due to the manufacturing year? So I know about the rockers, I've also read about different places of the fuel tank cap. Is there anything I've missed in your thread?

Thanks for your support in advance!