510 Race Car Build

[Stoffregen Motorsports]

Hey guys. Well, it's been over a decade since I've owned a Datsun, and I thought that I had let that chapter of my life go. You know the famous quote from Thomas Wolfe- "you can never go home again." That's where my head was at.

 

But...we bought a 510 to build as a race car.

 

I just got off the phone with my local vintage race group advisor and got some guidance as to what's allowed, and how far we can push things. I also had a conversation with Troy Ermish and it turns out, a lot of the hard to find parts are not as hard to find anymore. Like the gearbox. Troy is making them, so we'll buy one from him. Anyway, I'm getting ahead of myself.

 

The style of car that everyone is building now is 2.5 TA or B Sedan. Yes, I've always like that era of racer, especially in the 510, but I wanted to push the envelope and build an early SCCA GT4 car instead. I even went ahead and made contact with an old friend about building a clone of his 1983 SCCA National championship winning 510. His name is Dave Carkhuff and his car is on the inside cover of the How to Hotrod your Datsun book. I've known the guy since I was in my teens. But...the run-groups won't allow box flares, so unless we want to run with IMSA cars, bubble flares are going on the car. No GT4 car for us, at least not yet.

 

Now the hunt for parts begins. On the list of parts to source is a 4.38 R180, so if any of you guys have one, or see one, let me know. We will also need a couple sets of wheels. I've got a set of 13x7 Revolutions that I had on my baby blue 510 in the '90s, well, they aren't actually mine yet, but a friend has them and is willing to part with them. I'd like to get a couple sets of Libres too, so if anyone has any, please let me know. Carbs, manifolds, etc as well as any vintage race car stuff, like steering wheel or gauges, etc. Let me know!!!

 

No pics yet, but will upload some shortly. Oh, and this ain't hapennin over night. It's going to be a year or more before we're ready to hit the track.

 

I'm a Datsun owner again. Yay.

[carterb]

YES!

[datzenmike]

All '80-'82 720 4x4s had R-180 4.375 for the front differential. Thing is are they turning backwards on the 720 or are they going to be turning backwards on the back of a 510???? OR... does it even matter?

[iceman510]

Awesome!  I have a 4.38 R180 (from a truck no less) that I installed a Subaru clutch center in.  No, I'm not selling it. 😉

 

My vintage 510 has a Quaife rear end.

 

I remember Dave and that car.  Just around the time I acquired my first 510 from my brother in Long Beach and was just learning the legend and lore of the 510.

 

I have a bunch of vintage Stewart Warner gauges if you are interested.  Not sure how matching they are.  I might donate them to the cause.

Edited September 1, 2023 by iceman510

[Stoffregen Motorsports]

3 hours ago, datzenmike said:

All '80-'82 720 4x4s had R-180 4.375 for the front differential. Thing is are they turning backwards on the 720 or are they going to be turning backwards on the back of a 510???? OR... does it even matter?

It's actually a bonus that they were run backwards all their lives. The drive side will be virtually new.

[Stoffregen Motorsports]

3 hours ago, iceman510 said:

Awesome!  I have a 4.38 R180 (from a truck no less) that I installed a Subaru clutch center in.  No, I'm not selling it. 😉

 

My vintage 510 has a Quaife rear end.

 

I remember Dave and that car.  Just around the time I acquired my first 510 from my brother in Long Beach and was just learning the legend and lore of the 510.

 

I have a bunch of vintage Stewart Warner gauges if you are interested.  Not sure how matching they are.  I might donate them to the cause.

That's great. I'll hit you up.

 

Contact info? PM me.

 

I couldn't find any pics of Dave's car online, but that's not a big surprise. Supposedly he still has all the molds of the bodywork his dad made back then.

 

I'm not too worried about the carrier. I'll run a spool if I have to. Ideally I'd like to find a true LSD, like the OEM unit, which I can shim up to 65#. I still have all those tools including the tub axle with a socket welded to it for checking breakaway pressure. Troy says he has a different unit which uses lower breakaway pressure, but doesn't act like a Detroit.

[Stoffregen Motorsports]

4 hours ago, carterb said:

YES!

YES! is right. I kinda go over the top with the fab on my builds, so expect to see some fun stuff.

 

I can't have two race cars, so anyone want to buy a freshly built Sprite race car?

[datzenmike]

The later '83-'86 720 4x4 used a 4.11 R-180 if that helps. The '86-'89 WD21 Pathfinder use a short nose R-180 but it was a 4.625.

[Icehouse]

YES!!!!

[]2eDeYe]

This will be awesome 😄

[KELMO]

^^^What he said.

[Stoffregen Motorsports]

I hope so. I've built enough 510s to be able to do it in my sleep. That may be a bold statement since I haven't built one in over 20 years. Maybe muscle memory...?

 

One difficulty is correctness. Ideally the parts and mods would be era correct. Technology has improved drastically since the '70s, and you have to exercise restraint while you've got the cutoff wheel out, sacrificing performance to maintain authenticity.  Simpler is better in the end.

 

There are two specific parts that I need help with. I would like to build an exact copy of the brake fluid reservoir that was used in the BRE cars. I've seen it, and can picture it in my head, but if anyone has pics of the BRE engine bay, or the fluid reservoir, that would help a ton. If anyone has access to that car, maybe some measurements?

 

Another part is a period correct oil to water heat exchanger. I had a chance to buy one that was used on an actual BRE car. That was also over 20 years ago. Doug Barnhold had it in his chicken ranch parts stash. I did buy a pair of carbs and manifold from him, parts that were on one of the BRE cars, but I sold those to Troy back in 2002. So yeah, anyone have pics of a BRE heat exchanger?

 

To be clear, I'm not building  BRE replica. Just certain aspects.

[carterb]

22 hours ago, Icehouse said:

YES!!!!

 

You're funny Jeff.

 

Now then...  Where are the pictures of this thing anyway?  Doesn't Ratsun ban people for getting this far into a new thread with no photos?!

[KELMO]

Carter makes a valid point.

[datzenmike]

The 720 diesel had a oil/water heat exchanger under the oil filter so did VW. Warms the oil much much faster and then keeps it cooler at the expense of the cooling system. Is there room for it on a right leaning L series?

 

The 280zx turbo automatics (maybe the manuals too?) have a fitting under the oil filter for a remote oil cooler. If keeping all Nissan.

[Stoffregen Motorsports]

The BRE heat exchanger was a cutom piece that mounted away from the engine. I had it in my hand, but never saw it on a car. I recall it having four AN ports, on on each side of the rectangular shape.

 

Ok, ok. I'll snap some pics. The car isn't great. It's just a roller.

[paradime]

So glad to see you're back in the 510 saddle again. If Troy is building the sprocket box, could he change the output ratio allowing you to create the ideal gearing and final drive? I know companies like Sharkwerks are doing this, but it may be outside Troy's abilities, or WAY too expensive to justify. Can you use a 240 5 speed, or are you limited to a stock 4 speed?

 

I'm following this build for sure. God speed my friend.

Edited September 4, 2023 by paradime

[Icehouse]

3 hours ago, paradime said:

So glad to see you're back in the 510 saddle again. If Troy is building the sprocket box, could he change the output ratio allowing you to create the ideal gearing and final drive? I know companies like Sharkwerks are doing this, but it my be outside Troy's abilities, or WAY too expensive to justify. Car you use a 240 5 speed, or are you limited to a stock 4 speed?

 

 

Gearing is interesting to experiment with.  We have over the years ran different gearing and it seems less shifting is the fastest even if it doesn't feel like it.  Shifting takes time which adds up after a full lap.  

[paradime]

4 hours ago, Icehouse said:

 

 

Gearing is interesting to experiment with.  We have over the years ran different gearing and it seems less shifting is the fastest even if it doesn't feel like it.  Shifting takes time which adds up after a full lap.  

 

True that. Less shifting is not only faster, there's less chance of shifting mistakes. A high revving L engine has a broad top end power range. The ideal gearing for that can make a huge difference. Switching to a smaller GT-X2867R in our SR20 swapped 510 gave us enough low end power and torque not to have to down shift into 1st or 2nd coming out of a tight corners. It's kind of the other way around for less shifting to get faster laps.  

[Rustbin]

Given all the knowledge and insight you've shared on this site I'm really intrigued on what you are going to do with this car. All I know about the BRE cars is what I have read in the How to hotrod and race your Datsun book that I've had for decades so I really want to come along for the ride. 

[Stoffregen Motorsports]

@paradime and @Icehouse - I'm not exactly sure what the ratios are that Troy is making, but he did mention that these are not direct drive boxes, like the old "option" transmissions from Datsun Comp. So they must be overdrive...? They are close ratio though.

 

Note - the "close ratio" 5 speeds that came in Z cars are nothing like the racing close ratios. Not in the ballpark. Not even the same sport.

 

It was a short conversation with Troy since he was at the track and I didn't want to distract him, but it sounds like he's making new gears with dog engagement built in, not like the original two piece gear with the engagement teeth pressed on. They are dog boxes though, which means lift-and-shift. No clutch needed, so to your point about time wasted during shifting, less time is needed when you're not using the clutch.

 

FWIW, the box in our Sprite is a dog box and we still use the clutch. Maybe it's the SUs which don't respond as quickly as a carb with and accell pump? Just speculating...

 

I called Dave Rebello yesterday to pick his brain. He was out on the property planting trees. I'm glad to have his friendship, and it's sort of cathartic to think that he's kind of done with racing. New chapters and all that. Reminds me of the scene in Days of Thunder where Harry Hogge is out on the tractor when Cole shows up to talk racing.

[Stoffregen Motorsports]

13 hours ago, Rustbin said:

Given all the knowledge and insight you've shared on this site I'm really intrigued on what you are going to do with this car. All I know about the BRE cars is what I have read in the How to hotrod and race your Datsun book that I've had for decades so I really want to come along for the ride. 

Thanks for that. I hope this project is up to the standards everyone expects.

[metalmonkey47]

haha welcome back to Datsun ownership. I haven't had a Datsun since 2015, and I'm pretty sure I'll have one again very soon. Not quite 10 years, but time sure does fly.

Edited September 5, 2023 by metalmonkey47

[Stoffregen Motorsports]

You have a specific car in mind? Or you're just expecting something to show up at your door...?

 

Thanks. I feel like I should have stuck with the 510s. The main reason being, most of the 510 owners now days don't really understand the true historical significance of the car. Nor do they understand "the right way" to build one. Feels like I'm stirring the pot here, but I'm not. It's a thing. New guys are viewing through a different lens, which is understandable.

[Diabolic kustoms]