gemellocattivo.com
http://gemellocattivo.com/forum/

FrankenFerrari - V12 ferrari 308 part 4
http://gemellocattivo.com/forum/viewtopic.php?f=2&t=319		 Page 220 of 222
Author:  mk e [ Thu Feb 22, 2024 8:01 am ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
MerlinTech wrote:
With the cylinder shims, will you make a thicker shim and trim each cylinder to the proper protrusion?


I could...I think with 2 size shims I could get then all pretty close. Right now the difference liner to liner is 1.2 thou, and after it would be about 0.6 thou I think so pretty good or lap the tops of a couple and get it to maybe 0.4 thou...if math works out here anyway.
Author:  mk e [ Thu Feb 22, 2024 10:00 pm ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
I ordered the shim stock, I think it said delivers Saturday

Then moved on the finishing up wiring the transductors,. I still need to rezip tie stuff but they work so I moved on to adjusting all the new knobs on the brakes. It was a little more finicky than I was expected but after about 30 minutes the measured curve seemed to match the spread sheet numbers pretty well. I created a new tab in the ECU display for chassis data figuring I'll add GPS and steering at some point.
Attachment:
Brake log.JPG
Brake log.JPG [ 230.85 KiB | Viewed 2504 times ]


This is maybe only interesting to me but I replotted the calculations with G force on the bottom and realized that the mechanical bias takes me to 0.5 g which is really all normal driving and it doesn't take a lot of pedal pressure to get to line pressures that should be 0.5g with the new pads. The 1st proportioning valve is 0.5-1.0g which is the limit of most street tires 2which is clearly why factories set up the brakes with 1 valve. The 2nd valve works 1.0-1.25G which is DOT race tires and the 3rd valve is 1.25-1.5 which is slicks and that is pushing friking hard on the pedal. The proportioning valves are throwing pedal force away and by 1.5G I'm losing about 25% if I'm doing the math right. It also kind of shows why when you get good tires all of a sudden the rear starts locking and the brake pad people offer lower friction rear pads to help sort it.
Attachment:
brake pressure v G force.JPG
brake pressure v G force.JPG [ 77.24 KiB | Viewed 2504 times ]
Author:  MerlinTech [ Fri Feb 23, 2024 7:23 am ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
You have way more going on in your head than I ever could. I follow it but could not pass it on to someone else. Very interesting stuff.
Author:  kkrace [ Tue Feb 27, 2024 5:21 pm ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
Seems like a hard calculation to make on the brake bias. So much depends on how much dive, CG and weight transfer and road conditions. The more grip the lower the braking needed at the rear. That's why racers always bias more to the rear on rainy or cold days.
Author:  mk e [ Wed Feb 28, 2024 7:47 am ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
kkrace wrote:
Seems like a hard calculation to make on the brake bias. So much depends on how much dive, CG and weight transfer and road conditions. The more grip the lower the braking needed at the rear. That's why racers always bias more to the rear on rainy or cold days.


I think I have the math close but the plan is to measure g force, line pressure and the actual rear lock up point once its running again and then make the final adjustments from that info. All the math is based on g force load so road conditions and tire grip are baked into that input and the output is the rear grip. Its also not the plan to set anything at the limit, I baked a 10% safety factor into the math and the plan is to keep that in the final calibration with the goal to have brakes that work much better at speed than stock and are safe in all weather....good street car brakes not race car brakes.
Author:  MerlinTech [ Thu Mar 07, 2024 6:56 am ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
Everybody good? Just checking in.
Author:  mk e [ Thu Mar 07, 2024 8:55 am ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
I started making the shims to raise the liners a couple weeks ago but not knowing when the head gaskets will be coming I'm not sure how much of a hurry I'm in and finish grinding to size is pretty tedious so I take any excuse to do anything else. The brake pads I ordered still show as "processing" so hopefully they do actually ship at some point.

Last weekend I took my son out test driving cars. We found a 2019 toyota 86 that was a manual trans so his test drive was in an empty parking lot learning to work it. Pretty fun car. But the highly of the day was the 2023 supra. the dealer said a hard no to him driving it but that may have worked out for the best as there was a lot of hunting for grip on the cold wet roads which had him smiling ear to ear. The supra was at a bmw dealer so we looked at a 240M and 430xi then off to see a 370Z. The idea was to see a few things in person and try to convince him that the cheapest of the cars is by far the best but somehow that didn't work :lol:

Also spring is kind of here....so the clock may have run out on v12 work for a bit.

Attachment:
20240225_133926.jpg
20240225_133926.jpg [ 3.45 MiB | Viewed 2185 times ]

Attachment:
20240225_134034.jpg
20240225_134034.jpg [ 3.45 MiB | Viewed 2185 times ]
Author:  MerlinTech [ Fri Mar 08, 2024 7:08 am ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
Always interesting at your house. I have been through the new driver routine twice. It works out.
Shims look good. I think this is going to work.
Author:  mk e [ Thu Mar 28, 2024 8:37 am ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
Car shopping task complete. I was planning to buy something at auction and repair it but this popped up for not much more than I figured we'd spend and we could drive it now plus I don't need to give up space in the shop nor my time.
Attachment:
supra.JPG
supra.JPG [ 97.92 KiB | Viewed 1627 times ]
Author:  Syscrush [ Thu Mar 28, 2024 12:20 pm ]
Post subject:  Re: FrankenFerrari - V12 ferrari 308 part 4
Here I thought he was kinda spoiled for having a pool and a pizza oven. :lol:
Page 220 of 222 All times are UTC - 5 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group
https://www.phpbb.com/