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Searching around all I could find was people looking to relocate to the rear of the car.
Due to race regulations (NASA) requiring that the battery be in a "marine style battery box" if it is going to be in the cabin with the driver, it eliminates that area of the car as an option as the battery box is quite large. I know I could get a smaller battery but those are $$ that I need to spend elsewhere to get the car on the track.
Putting the battery on the rear deck seems counter-productive as it seems like it would be higher than the factory placement. I was wondering if anyone else had put the battery in the rear inside of the passenger floor pan to keep the center of gravity low?
My primary reason for doing this is because the factory battery location has a hole rusted through it and doesn't seem like a safe location to strap the battery for racing.
I set the box in the location I want and put a passenger seat in to see if I could still have a passenger for DE and it looks like it would still be fine if the seat is up against the box.
This is with the big clunky seats the PO put in and not the seats the car will be tracked with so the passenger should get a couple more inches with a thinner profile seat.
When running the negative cable, should I just run it to the chassis or to the engine block?
There is very minimal electronics left in the car so I feel like for max cranking power it should go to the engine block and allow the engine ground strap to provide ground to chassis but I could be way off on that.
You also say original mounting "not safe for race" so it's assumed that you are planning to be signed off to race with instruction then proceed to race the car..?
If so, I would just tack two 1"x 1" angle steel the length of the battery at the factory location to strengthen and mount battery while needing the passenger seat, then move it to front floor right under factory position. Eventually when racing, to counterbalance driver weight during setup, you need moveable weight to be over RF and Rr tire as much as possible. The way the fuel tanks are made, the first 5-7 gallons sits in the lowest and farthest right portion of the tank's sump.
Later, use bulkhead pass through connectors from battery to firewall, then using good condition factory +/- cables, connect to other side of those and leave remainder stock.
Yes by passenger I mean instructor. I will be using the car for both DE to get cleared for racing and then proceed to racing with the same car.
It sounds like I'm trying to configure it to work best with both situations when I need to focus on each independently.
Yep, the temporary under hood solution lets you disregard the plastic container for now.
I am reconfiguring a 968 that belongs to an instructor buddy and my son will periodically race, It was setup for Vintage racing on 200 tread wear street tires and had battery in plastic container.
My son races another 944 in PCA and has records in PTD or E NASA but they never said anything about his battery not being in a container....?
And I never read their rules....
In proper setup, like I said earlier, if you progress to the point where every consideration matters, ultimately you will be looking to counterbalance the weight of the driver with physical, moveable weight. Gas tank and battery gets you close without extreme jacking of coilovers.
BTW, I've got a new, never been raced autopower bolt in cage, OMP Pista race seat and a set of non adj. Leda coilovers valved for 400F/650Rr.
Gonna post some stuff with pics at Pelican in then next couple of days.
In proper setup, like I said earlier, if you progress to the point where every consideration matters, ultimately you will be looking to counterbalance the weight of the driver with physical, moveable weight. Gas tank and battery gets you close without extreme jacking of coilovers.
It's going to be a long time before I get to the point where slight weight balance changes are making a difference in my driving, lol.
That being said, if I'm going to make any changes to the car I would like them to be rooted in things proven on the track, so I try to do as much research as I can. Obviously changes to the car over time are going to happen but it never hurts to get started in the right direction.
Originally Posted by 951and944S
BTW, I've got a new, never been raced autopower bolt in cage, OMP Pista race seat and a set of non adj. Leda coilovers valved for 400F/650Rr.
Gonna post some stuff with pics at Pelican in then next couple of days.
Good to know!
I mostly tend to troll the forums for used race parts being that most of the questions I have can be answered with a quick search. I'll keep an eye out for it!
If the seat and headroom allow it (keep the instructor comfy)...could you put the marine battery box in the "rear seat footwell area" on the floor behind the passenger side?
If the seat and headroom allow it (keep the instructor comfy)...could you put the marine battery box in the "rear seat footwell area" on the floor behind the passenger side?
Yup, that's what he was going to do originally. For me, two things beside the lesser opportune weight issue makes that locale less attractive.
To keep cables short, people generally seem to use a roll cage mounted on/off battery switch near the battery location. Tech wants clearly marked shutoff (with proper decal) and they generally don't want to have to reach in the car for it.
Almost certain too that, if inside, driver must be able to turn switch off which means you have to run a cable to the switch lever because there's no way to reach it when buckled in harness in a high bolstered race seat with a Hans.
The engine must test to kill at 2000rpms as a safety feature when switch is turned to off position, so I use the +12V coil wire at the switch to open the circuit, which means you would have to make two runs all the way from the coil to the switch, one to and one from. My switches are mounted outside, easily marked and reached by a corner worker on passenger rear of hood.
It's going to be a long time before I get to the point where slight weight balance changes are making a difference in my driving, lol.
That being said, if I'm going to make any changes to the car I would like them to be rooted in things proven on the track, so I try to do as much research as I can. Obviously changes to the car over time are going to happen but it never hurts to get started in the right direction.
Don't sell yourself short. You stand as good a chance as anybody to be a natural.
And yes, configure the car once and be done.
I tend to disappear from here for months at a time but post race questions....somebody else will eventually answer.
There are a couple of PCA 944 racers we know up your way (fairly local) that might be good local sources of help.
Porsche Club has instructors and events local to you too, is there a reason you are going the NASA route...?
Porsche Club Race at High Plains Raceway is coming up in a few weeks, June 17-18.
It's also the Midwest Regional for 944Cup...., bound to be some 944s there.
I sometimes drive around with marine style box and 75ah battery in passenger footwel, there is enough space for passenger. Just make sure you vent the battery outside.
Just get a lightweight tractor battery and mount it in factory location with a couple of metal straps. Saves weight, cheap, and easy to replace if it dies, at any Walmart or Tractor Supply. Mine was 10-12# max and cost under $50. It's a race car so there's not much draw, so even if I forget to pull the kill-switch during long time storage, it starts right up.
Just get a lightweight tractor battery and mount it in factory location with a couple of metal straps. Saves weight, cheap, and easy to replace if it dies, at any Walmart or Tractor Supply. Mine was 10-12# max and cost under $50. It's a race car so there's not much draw, so even if I forget to pull the kill-switch during long time storage, it starts right up.
I guess generally, we aren't looking to shave weight at the battery, car has to meet minimum and I would have thought a 968 (SP3..?) at 2900 it wouldn't be a concern for you either.
Always good to be able to get a replacement around the corner from any track though.
As far as current draw, short of Sebring night race, the most current draw items are still used on a race car.
Bosch 044 pump = 15-25 amps
12V coil - 5-7 amps average - instantaneous can be higher (why engine misfires when alt failing before total dnf)
WW motor 9-10 amps
the actual rear seat butt-dent would be a good place for a battery box if your cage allows it.
then you could run the kill switch up to the rear side window area.
Just get a lightweight tractor battery and mount it in factory location with a couple of metal straps. Saves weight, cheap, and easy to replace if it dies, at any Walmart or Tractor Supply. Mine was 10-12# max and cost under $50. It's a race car so there's not much draw, so even if I forget to pull the kill-switch during long time storage, it starts right up.
This is good to know and definitely something I will look into!
Most of the light weight batteries I've seen around cost quite a bit which is hard to justify when I have a perfectly good heavy battery lol.
Originally Posted by V2Rocket
the actual rear seat butt-dent would be a good place for a battery box if your cage allows it.
then you could run the kill switch up to the rear side window area.
Ya I measured this spot initially. I'm really tall, though, so the diagonal of the cage will go right through that area.
Originally Posted by 951and944S
Porsche Club has instructors and events local to you too, is there a reason you are going the NASA route...?
The NA engine in my car is on the way out. The lifters are sticky and make a wicked clacking noise, it leaks from every seal, the motor mounts are shot, and I'm not sure my electric water pump conversion is allowed on a spec car (although it's been a minute since I've read spec rules).
Overall the cost and work to bring it back seems a bit excessive for the power it puts out so I'm working towards a swap. That is primarily why I'm going NASA, plus I like the idea of doing TT to build my skills before going wheel to wheel.
I'm on the fence on whether to try and find a 3.0 to keep things in the family or swap in something else. I like what MotorWerks racing has been doing with the Audi 1.8t so that might be a good option... it's still up in the air though. For now I'm going to keep the factory NA until it explodes.
05-21-2017, 05:14 PM
Race battery relocation - passenger floor pan
