icantlearn

You should calculate the power to weight ratio and compare them. FOR SIENCE!

codrus

Well, at 750 crank hp he's got roughly twice as much power as I do, and my Miata is fairly heavy (2400 pounds empty).

Down the front straight in 5th though, the speeds are high enough that aero is a big factor. The hard top is good for 5-10 mph in top speed, and even with that the Miata is still a fairly high-drag car.

--Ian

aidandj

iTrader: (5)

RE Fuel starvation.

Spent some time getting intimate with the Miata gas tank. There is a bucket that the fuel pump sits in. Should hold fuel in cornering, when the level is below it.

I'm wondering if your return system is returning the fuel up high, which is allowing it to fall out of the bucket in high G corners. Where cars that came with a return system are dropping it back in the bucket.

So its not an aeration issue, it could be the fuel is going to the wrong place. So a 90* fitting might make it worse. I would suggest returning the fuel right next to the stock, and allowing it to stay in the bucket.

Its also possible that you are just using so much fuel that you are emptying the bucket before it is able to be filled again.

sonofthehill

iTrader: (1)

I like the idea of returning to the sock. My question is how the bucket fills up, are there more filling port holes on one side?

aidandj

iTrader: (5)

I'll grab some pics before I close it all up.

sonofthehill

iTrader: (1)

Perfect, thanks! I wish I had paid more attention when I did my pump.

aidandj

iTrader: (5)

So whats interesting is that the fuel gauge will read zero before the fuel is below the top of the bucket. So it usually fills up just by being below the fuel level.

sonofthehill

iTrader: (1)

So the sides of the bucket actually sit up off the bottom of the tank, not a sump? Just a baffle to keep fuel near the pump?

Are these images at empty on the gauge?

aidandj

iTrader: (5)

Bucket is about 3 inches deep. Has a hole in the left bottom. Had a lot of fuel in the pics

sonofthehill

iTrader: (1)

Maybe bolt a little lip to the small holes on the one side so fuel wouldn't be as likely to jump the edge of the bucket.

sonofthehill

iTrader: (1)

A horizontal lip on the inside of the bucket, are those 2 little holes at the top?

sonofthehill

iTrader: (1)

A small piece of angle with 2 holes would do.

aidandj

iTrader: (5)

I don't think fuel is jumping the bucket. There are other high grip cars that don't have this issue.

sonofthehill

iTrader: (1)

Then returning to the sock it has to be.

codrus

I think the "not returning to bucket" idea makes sense. Here's a datalog of turn 5 in a case where it didn't starve:



Red is the computed fuel pressure error, green is TPS, blue is lateral accel. The corner starts about halfway along the graph (19.98 km), where the blue line dips down below the center (centered on 0). The green line comes up (cornering throttle), then at 20.072km the FP error dips into the negative range. At 20.12 km I get back to WOT and FP error drops HARD, down to -15 kpa. By 20.17 km it has fixed itself, and is hovering right around zero again.

Here's a datalog from the same corner on the next session with a full tank, no dip.



So it makes sense to me that when the car is loaded up, the stream of fuel from return that's dumping halfway down the bracket is getting bent by the gee force and is missing the bucket. That would mean that the fuel pump is busy emptying the bucket while in the corner, then has no fuel available when I'm coming out of the corner and getting on the throttle.

I bought one of these fittings that G pointed to, with the intention of running a hose down to the bottom next to the sock.:



--Ian

DNMakinson

iTrader: (3)

See post 910. That is the wrong part.

EDIT: If you want me to, I will flare a 6" piece is stainless tube and send it to you. You can se what I did at post #119 of my build thread.

codrus

Argh, I missed that post. Ordered the correct one now.

I was thinking of just shoving a piece of hose on there. Let me try that and see if it solves the problem before going with hard parts.

thanks,
--Ian

concept29

Hi, turbokitten
Thanks for your sharing.
I want to make a dashboard for microsquirtmodule. I wanted to use your code for learn but not working for me.

I have a nextion 2.8 and use mcp2515 module , arduino UNO
Wiring the MCP2515 Controller Area Network CAN BUS Diagnostics 14Core.com

I connected :
- Nextion : Black - GND, Red - 5v, Yellow - Digital pin 4, Blue - Digital pin 5. Bauds 115200.
- MCP2515 module 8Mhz: int - Digital pin 2, Cs - Digital pin 9, Si - Digital pin 11, So - Digital pin 12, SCK - Digital pin 13, GND - GND, Vcc-5v
- Microsquit Module: CANH - pin 10, CANL - pin 12
http://www.msextra.com/doc/pdf/Micro..._Guide-3.3.pdf

In Tunerstudiio: CAN Menu is not the same for MS3 and microsquirt (i can not t setting frequency by group 0,1,2,3 there is only one choise), i have tested, Enable CAN realtime data broadcasting with ID 1520 And rate 50Hz. Do not works. Then i have tested Dash broadcasting in automatic, do not work again.

Can you help me for just display a sample (rpm by example).

codrus

Swapped out the shocks on the truck for some Bilstein HDs today. Dunno what the old ones were -- they came with the truck and might have been 150K originals. The Bilsteins are a huge win.




$272 shipped from Tire Rack. Highly recommended if you've got a big tow vehicle.

--Ian

sonofthehill

iTrader: (1)

I got 120k on my work truck's HD bilstiens. Best handling truck I've ever driven.