280z FP Build

[Ben280]

 

Particularly good shot of the car climbing the hill into T11 at the Ridge at GTA '22

[Ben280]

5 minutes ago, AydinZ71 said:

@Ben280 Hey Ben! So I'm working with Robello's head guru and I asked him about the stripped worm gear & sprocket phenomenon. Only time I have seen the oil pumps fail is what you experienced. He mentioned the critical consideration is sufficient lash. He has only seen it happen when the interface is too tight and there isn't enough shaft play. I don't remember the number he gave me, but I remember being surprised how much play he recommended (big number). Il probably ask him again before my motor goes in, and Il put it up here. He doubted the dizzy removal was the cause. 

Hey! 

 

That bodes well for the resale value of my Hoke trigger kit then! There's a fair bit of play in mine. I wasn't doing anything fancy with the shaft placement, apart from using the later KA truck oil pump for a bit more oiling. As far as I've been able to tell, they are essentially the same casting, just different springs. It would be interesting to know, although I think I've since binned the pump. Worm drive, sprocket and camshaft are going on the altar to the Gods of Speed in the new shop.

Edited August 31, 2022 by Ben280

[JMortensen]

What rear gear ratio are you running? After reading Jerico I've been thinking about that. Maybe you have OD 4th, I know they make them, but with 1:1 and 3.54s I worked out a top speed of about 133 mph with a guessed tire height of 25.5

Edited August 31, 2022 by JMortensen

[clarkspeed]

Thats a good idea to add another safety feature when using a crank trigger. I will think about that for my car.

 

I had a drive gear shear off like that 1 time. I attributed it to hitting the track full steam before the oil was warmed up. Cooler the oil, more torque required to turn pump. NISMO used to sell a brass gear substitute for the crank gear to prevent failure on race cars. Since then I have always made sure the oil temp was over 140 or so before doing high revs. 

 

 

[Ben280]

I have a long nose 3.90 in the car, and a 1:1 4th in the Jerico. That pegs top speed at 126 with an assumed 6500rpm rev limiter. I might start hunting for a 3.54 short nose diff, since that would bring my top speed up 13mph, and I could likely widen up my ratios. First gear is pretty tall on account of the L having a narrow powerband, and trying to keep the drop small from 3rd to 4th. 

 

@clarkspeedInteresting idea. Maybe it develops internal weakness that come out at high RPMs? I tried to be pretty nice about getting the car hot before hitting the track, but maybe I missed the mark a few times. Tough to say, and it wasn't something that I thought to keep an eye on. When I had the motor apart last year, I didn't notice anything weird about that area. 

[JMortensen]

15 hours ago, Ben280 said:

I have a long nose 3.90 in the car, and a 1:1 4th in the Jerico. That pegs top speed at 126 with an assumed 6500rpm rev limiter. I might start hunting for a 3.54 short nose diff, since that would bring my top speed up 13mph, and I could likely widen up my ratios. First gear is pretty tall on account of the L having a narrow powerband, and trying to keep the drop small from 3rd to 4th. 

I was talking to a friend with a GTI and he was telling me that he was doing 145 at the end of the straight at the Ridge. When they first opened they were saying a stock C6 Vette could do 150. Are you just topped out in 4th waiting for the braking zone? Pacific Raceway is dangerous, eats a lot of cars, so I wanted to go to Ridge but I figured I'd be doing 170 at the end of the straight and was honestly a bit scared of it for that reason. Figured I needed a wing before I tried it. Thoughts?

[tube80z]

18 hours ago, clarkspeed said:

Thats a good idea to add another safety feature when using a crank trigger. I will think about that for my car.

 

I had a drive gear shear off like that 1 time. I attributed it to hitting the track full steam before the oil was warmed up. 

One thing I'd advise is if you decide to use alarms in your data system/dash to auto shutdown that you create a dual-channel alarm strategy where you have two sensors or another way to back into the data for a sanity check.  Over the years I've seen far too many races lost when a team stops the car and finds out either the sensor failed or a wire fell off or was destroyed with heat.

 

Fire suppression is another area where this strategy is handy.  It's great to have an onboard system but also have access to a handheld one can often put out the fire.  The onboard systems generally don't do this as they are mostly intended to buy the driver time to bail out.

 

 

[Ben280]

The Z (with higher RPM) would just hit 130 on the front straight. The video I posted is WOT until the 2 cone marker, and just hitting that marker. With more power and less gear, I'd probably be pinging rev limiter until the brakezone. 

 

Most modern high performance cars cars are getting 140-150. The 800hp Viper that holds the production record there tagged 171 on the front straight, and camero ZL1-1LE's will get to about 150. 

 

No interest in Pacific, but the COTNW in Bremerton looks really interesting!

 

I like the idea of running dual sensors @tube80z, you'll hear a lot of radio chatter about failing out sensors. It's also just good practice to get good sensors, and keep tabs on em! Intermittent electrical issues are the worst!

With the swap, I'm going to be re-wiring the front half of the car. Prior to my motor exploding, I'd gotten my hands on a Motec C125 dash and a PDM30. Need some other accessories, but this seems like a real good time to get them installed!

[Ben280]

Latest and greatest update. 

 

Moving on from the Koni/GC combo finally. I worked with Jonathan at Shaftworks to build some custom dimensioned struts for the car. The fronts have S13 mounting dimensions (which I built my front uprights to accept) and the rear are 2002-2005 WRX. I'll probably have to put some serious work into the rear T3 knuckles to accept that fit, but we'll see. 

[AydinZ71]

9 hours ago, tube80z said:

One thing I'd advise is if you decide to use alarms in your data system/dash to auto shutdown that you create a dual-channel alarm strategy where you have two sensors or another way to back into the data for a sanity check.  Over the years I've seen far too many races lost when a team stops the car and finds out either the sensor failed or a wire fell off or was destroyed with heat.

 

Fire suppression is another area where this strategy is handy.  It's great to have an onboard system but also have access to a handheld one can often put out the fire.  The onboard systems generally don't do this as they are mostly intended to buy the driver time to bail out.

 

 

I felt a bit guilty for this (I shared with Ben): his unfortunate accident gave me an idea for a secondary oil pressure sensor. Instead of a broad spectrum sensor, I’m thinking a more reliable (simpler) pressure switch set to something like 4-10psi (for idle). The switch would connect to a micro (super bright) LED I sourced but also cut-out my ignition system via a relay. I could “arm” the system with a switch, but a more complicated timer delay is also possible (so I can start the car). I’d rather have the engine die than run at 0 pressure! The pressure gauge seems more like a troubleshooting instrument than a means to immediately address a serious problem. 

[AydinZ71]

On 8/31/2022 at 3:50 PM, clarkspeed said:

Thats a good idea to add another safety feature when using a crank trigger. I will think about that for my car.

 

I had a drive gear shear off like that 1 time. I attributed it to hitting the track full steam before the oil was warmed up. Cooler the oil, more torque required to turn pump. NISMO used to sell a brass gear substitute for the crank gear to prevent failure on race cars. Since then I have always made sure the oil temp was over 140 or so before doing high revs. 

 

 

Oh snap! Yeah that totally makes sense. When Ben first told me about it, I thought something came loose and jammed the gear which would naturally cause the sprocket or worm gear to shear. High oil back pressure would certainly stress the gear. Always something to learn here 

[clarkspeed]

On 9/1/2022 at 11:31 PM, AydinZ71 said:

I felt a bit guilty for this (I shared with Ben): his unfortunate accident gave me an idea for a secondary oil pressure sensor. Instead of a broad spectrum sensor, I’m thinking a more reliable (simpler) pressure switch set to something like 4-10psi (for idle). The switch would connect to a micro (super bright) LED I sourced but also cut-out my ignition system via a relay. I could “arm” the system with a switch, but a more complicated timer delay is also possible (so I can start the car). I’d rather have the engine die than run at 0 pressure! The pressure gauge seems more like a troubleshooting instrument than a means to immediately address a serious problem. 

All my previous cars I ran a pressure gauge on dash, gauge on the Accusump I could see from my seat, and a pressure switch wired to a big yellow light on the dash I could not miss.

On the new car I will have a programmed readout/warning as described above, but will still have the Accusump gauge as a redundancy reading. And if I dry sump, I will add back the switch/light. 

 

[calZ]

On our racecar we ran two pressure gauges - one sensor at the pump outlet and one at the Accusump outlet. Both had switches connected to lights as well. The pump outlet had a yellow light to let us know if there was oil starvation in a corner, and the Accusump light was red, since if that one dropped too low it meant the engine had no pressure left at all. We were very happy with the setup. 

[AydinZ71]

@tube80z Makes a lot of sense to utilize all sorts of functions if you have a PDM. I looked into the AIM units a while back but I still need to learn to drive, let alone data analysis/utilization haha. Saving grace is all my gauge sensors are electronic (even the 2” gps speedo) so I can use the data in the future beyond just the autometer gauges. Good idea to remote-mount the oil pressure sensors. Not sure I can do the same with the oil temp sensor since I’d prefer to nab the reading straight from the oil pan. 
 

@clarkspeed ahh so you also did the pressure switch triggering a light! Glad I’m not way off base. I have a local indicator gauge on the accusump too, but the whole unit is remote mounted in the engine bay.

 

sorry about digressing from your post Ben! 
 

 

[clarkspeed]

This was a horrible hi-jacking. My apologies. You car is incredible. 

[Ben280]

Haha! I'm all for a discussion about important race related matters such as oil pressure. I might be unhappy to be the catalyst for such discussions, but not disappointed to host them in my build thread. 

 

I've started working on the wiring harness. I have a friend who builds some really spectacular stuff for prototype cars, and offered to help me get a new engine and chassis harness sorted out for this car. We are trying to do it right, and he's managed to score some pretty serious hardware for me. 

 

 

We are using a Motec PDM32 which is all autosport connectors. One thing has lead to another, and he might be going a bit wild on the construction with the twisting and sheathing. 

 

This is all going to look hilarious next to my Megasquirt ECU (rebranded as a Notec from here on out!)

[jonbill]

This is my oil pump gear and spindle from 2017. I put it down to the load from the turbo oil pump and lots of revs. 

I replaced with a bronze drive gear and its been fine since. 

[JMortensen]

This looks amazingly similar to Mark Haag's drive gear failure, which he noticed at idle IIRC, so he also didn't destroy his engine. Messaged him to see if he still has the pic or wants to jump in on the thread.

Edited September 9, 2022 by JMortensen

[JMortensen]

Mark sent a picture. Looks like they were using a borescope.

Said it happened a different time and sheared all of the teeth off, sounds more like Ben's failure.

Edited September 9, 2022 by JMortensen

[calZ]

So what I'm getting out of this is that I should run a bronze drive gear.