4G63 510

[jeffball610]

The brakes seem to be bedding in better, but now the car is torn apart for the next mods.

 

I've been using a stock DSM oil pan for all of the 25k miles I've put on the car. it's not ideal, as the engine sits at an angle in those cars. So I'm going with a RWD oil pan from a Mighty Max/D50. In doing so, I'm making a baffle to control some oil slosh a bit. Nothing fancy. Right now I'm taking out the DSM oil "splash plate" to fit in the Mighty Max pan and go from there.

 

I'm also switching out my turbo setup. The "old" turbo did well for all the miles I've done, but I'm trying to get better spool response for the driving I do. So I'm switching to a 68HTA v3 from Forced Performance. The size comparison is comical.

[datsunfreak]

4 hours ago, jeffball610 said:

The size comparison is comical.

 

 

Yeah, but I bet the torque comes on a LOT quicker. 😁

 

I find turbos are a lot like cams. You rarely regret going too small, but almost always regret going too big.

[jeffball610]

20 hours ago, datsunfreak said:

Yeah, but I bet the torque comes on a LOT quicker. 😁

 

I find turbos are a lot like cams. You rarely regret going too small, but almost always regret going too big.

The plan is for quicker spool and better transient response. The turbo I had was great for the 400whp goal that I had. However, just making about 325whp is too much for the 205 width tires. It's a good turbo, but not for my needs at this time.

[datsunfreak]

3 hours ago, jeffball610 said:

However, just making about 325whp is too much for the 205 width tires.

 

Honestly, most (if not all) 510s struggle to handle more 225-250hp. It's tough to ever get enough tire under it to put that kind of power down.

 

But you know that already.  😁 

[thisismatt]

What about top end?  75mph passing acceleration?

Edited February 28, 2023 by thisismatt

[Icehouse]

I find at the Autox the off throttle almost the hardest part.  Going from any throttle to zero it really upsets the car.  I mean that's the fun of a turbo car but wow lots of mind power to get a fast lap.  Have you been at all this year?  I mean you gotta test those brakes.  

[Stoffregen Motorsports]

8 hours ago, Icehouse said:

I find at the Autox the off throttle almost the hardest part.  Going from any throttle to zero it really upsets the car.  I mean that's the fun of a turbo car but wow lots of mind power to get a fast lap.  Have you been at all this year?  I mean you gotta test those brakes.  

Trailing throttle oversteer. Pretty common with a semi trailing arm suspension. The toe changes as the suspension cycles, which is why guys slot their crossmembers.

 

There certainly is a balance between traction, horsepower and aerodynamic drag. To get a tire big enough to handle lots of HP, the car ends up being so wide that it pushes way more air. Top speed on a 510 is about 135 mph. I don't care how much HP you have, that's about it for a flying shoebox.

[datsunfreak]

On 3/1/2023 at 10:07 AM, Stoffregen Motorsports said:

Top speed on a 510 is about 135 mph. I don't care how much HP you have, that's about it for a flying shoebox.

 

Depends.  😁

 

Bursts, or sustained? Because this one goes to 11, aka 142mph...

 

http://www.speedhunters.com/2012/10/a-9-second-700hp-street-legal-datsun-510/

 

A friend who has a 400hp 510 once did the math (smarty pants engineer), and said what you said. 130ish is the limit of a streetable car. But that's because 10 miles an hour over that requires an additional 100hp, then 10 more over that requires another 200hp more, then 10 over that would need 400hp more, etc. 

[Stoffregen Motorsports]

5 hours ago, datsunfreak said:

 

Depends.  😁

 

Bursts, or sustained? Because this one goes to 11, aka 142mph...

 

http://www.speedhunters.com/2012/10/a-9-second-700hp-street-legal-datsun-510/

 

A friend who has a 400hp 510 once did the math (smarty pants engineer), and said what you said. 130ish is the limit of a streetable car. But that's because 10 miles an hour over that requires an additional 100hp, then 10 more over that requires another 200hp more, then 10 over that would need 400hp more, etc. 

That's awesome. We learned that the hard way, when all we needed was a smarty pants engineer.

 

The cars we learned on were GT spec SCCA racers. You could get them to work with wide tires and box flares, but then you're as wide as you are long, hence the shoebox.

 

Similarly, Lamborghini had a challenge a few years ago to make the lightest street legal car they could make. This was started by a debate about the weight of modern cars as compared to (in this case) a 1990 Honda Civic. Turns out, even with all the carbon fiber and lightweight materials and CNC machining, their street legal car, with approved crash standards, was still something like 3500 pounds. Makes you wonder what a car company like Lamborghini could do with a 510 shaped brick.

[datsunfreak]

11 hours ago, Stoffregen Motorsports said:

all we needed was a smarty pants engineer.

 

They do come in handy on occasion. 😄

 

11 hours ago, Stoffregen Motorsports said:

Makes you wonder what a car company like Lamborghini could do with a 510 shaped brick.

 

[paradime]

this one goes 143 mph 

[iceman510]

Not with all that backpressure.

[paradime]

It's Bōsōzoku, so it's not called "backpressure". It's "boost"; from an expertly tuned sonic pulse vectoring passive turbo exhaust system. Very cutting edge, but for deeper technical specs, refer to the manga Akira. 

[iceman510]

Ahh, manga, so it's allowed to be pretend.  😉

[datzenmike]

On 3/2/2023 at 1:00 PM, datsunfreak said:

 

Depends.  😁

 

Bursts, or sustained? Because this one goes to 11, aka 142mph...

 

http://www.speedhunters.com/2012/10/a-9-second-700hp-street-legal-datsun-510/

 

A friend who has a 400hp 510 once did the math (smarty pants engineer), and said what you said. 130ish is the limit of a streetable car. But that's because 10 miles an hour over that requires an additional 100hp, then 10 more over that requires another 200hp more, then 10 over that would need 400hp more, etc. 

 

Air resistance quadruples with every doubling of speed. All other losses ignored if it takes 100 HP to go 100 MPH then to go 200 MPH you will need an additional 400HP.

[paradime]

19 minutes ago, datzenmike said:

 

Air resistance quadruples with every doubling of speed. All other losses ignored if it takes 100 HP to go 100 MPH then to go 200 MPH you will need an additional 400HP.

 

Terminal velocity is 120mph, so theoretically, my 400HP 510 should do 250mph going down a 50% grade, but my 510 tapped out at about 145ish going down the Grape Vine on Interstate 5. What gives?

 

I suck at math, but I have internet access to people who don't. The power required for a 510 to overcome aerodynamic drag is not a direct 1:4 ratio. It increases as the cube of it's velocity as  .  I have no idea what all that shit means but... Absent all other sources of drag, the power needed to push a 510 down the freeway at 50mph might require 10hp. Double it to 100mph and it requires 80hp. Not inviting all the obvious drag coefficients of a short wheel base shoebox, and a host of other fancy drags I'm not thinking of, 200mph would require 640hp. My guess is the hood latch would give up at about 156.3mph, act like a front wing, and make it to 158 before flying into on coming traffic. 

[Stoffregen Motorsports]

4 minutes ago, paradime said:

 I have no idea what all that shit means but...

Yup. I got nothin...

[Satisaii]

I can explain it, but it is work/time and I am out of time.

[jeffball610]

Looks like my build page turned into a debate about off topics.

 

In any case, I finally got the car back together and sorted. The new turbo is awesome and much easier to control than the previous setup. I'm still getting used to how power comes on and how to control it. I make 12psi at 50% throttle and I'm only running about 16psi to manage traction in lower gears.

 

Here's a quick stitch of Sunday's autocross event at the Corvetter Museum course with KYSCCA. Sorry for the crap camera mount on my helmet and the weird crop to the video.

 

KYSCCA 6-11-23

[datsunfreak]

1 hour ago, jeffball610 said:

Looks like my build page turned into a debate about off topics.

 

[datzenmike]

 

 

 

My '70 Dart rated at 275 fact0ry (for insurance) was well over 300hp. A friend with the same car dynoed @ 310. Mine would do just under a buck fifty-five @ 6,100 and it's larger than a 510

[Duncan]

On 3/3/2023 at 12:37 PM, paradime said:

this one goes 143 mph 

 

 

Over a cliff on the way down, maybe?

[paradime]

21 minutes ago, Duncan said:

 

Over a cliff on the way down, maybe?

That's its Bōsōzoku clocked top speed. Using their official watch-o-matic 9000.

 

 

[jeffball610]

I haven't done much with the car due to weather and just not being confident. I put all of that aside yesterday and went to a local autocross event. The car did great and I'm making plans to drive it even more. I still need to improve my driving and I want to improve the brake feel and performance. But otherwise, I'm happy with where the car is right now while I make more plans to improve it in the future.