Or even use something like this

https://m.grainger.com/mobile/produ...t/PARKER-Hydraulic-Flow-Control-Valve-1A854?breadcrumbCatId=4219&fc=MWP2IDP2PCP
Posted via Mobile Device

 

Sounds great. Let us know what your pressure numbers are. Regardless of the front bushing, the restriction is still based on the oil return hole in the input shaft (front and rear), whichever is the smallest if you use the front bushing.


Hutch

 

Well I'm not too sure what to think at this point. I turned the car down to 5 psi to get some data on the road, the rpm drop on shift increased (by about ~400 rpm, was still getting 1500 - 1300 rpm drop on shifts on higher boost, yet 14% slip at the stripe), and the slip was noticeably less in high gear, even without a timeslip to compare the mph to RPM. Converter charge at idle is less than 10 psi. The pressures displayed on my log seem to be OK-ish (i think, starting to get a little low at higher RPM, and has a weird dip), the question is, under more power, will the converter charge pressure drop more? My local track is closed so I cannot test under more power for a few weeks. Here is a picture of the log, thanks for any help.

https://drive.google.com/file/d/1nCo2R-Dwcv-vQa7demRZlfBlsbd-0HeZ/view?usp=sharing

 

Converter pressure looks pretty good.


Hutch

 

Less than 10 psi at idle doesn’t seem right. What main line pressure do you have at idle?

 

I just rechecked line pressures. I was using 100% atf for the 180 psi readings previously, I now have some hyd fluid mixed in and the pressures are higher either due to that, or to me not revving the car high enough for readings before. this is what i have currently, and what I have had for a while, long before I started this thread.

Park-
idle line 140 psi
idle converter 15 psi
2k rpm line 210 psi
2k rpm converter 75

Reverse (with button pushed) -
idle line 110 psi
idle converter 3 psi
1800 rpm line 200 psi
1800 rpm converter 65

Neutral -
idle line 140 psi
idle converter 13 psi
2k rpm line 200 psi
2k rpm converter 70

1st -
idle line 150 psi
idle converter 7 psi
2k rpm line 225 psi
2k rpm converter 80

2nd -
idle line 150 psi
idle converter 6 psi
2k rpm line 220 psi
2k rpm converter 70

3rd -
idle line 115 psi
idle converter 3 psi
2k rpm line 210 psi
2k rpm converter 64

Valve body is an ATI wicked quick 1+2, pump is a high volume, with heavier spring only, no horseshoe spacer. Pressure sensor is a 0-500, so there may be a little bit of resolution issues at such low pressure, but i'm not sure. I'm going to throw a 0-100 sensor on when it gets here and make sure my original readings aren't out of wack.

I called the converter company and they said the issue is my gearing and tire, (3.27 and 28"), which is odd since I told them that would be my gearing and I would run both 26 and 28 tires when they spec'd it. They seem to think that if I put a 26" tire on then the slip will go down to single digits. It just seems odd to me that it would have that much slip at much less power than spec'd for, and the slip is getting worse with more power.

 

You'll have other issues going forward.

 

Mr. Hipster, I'm unsure if you are saying I'll have worsening issues with the converter the more I push the car, or if my pressures indicate another type of issue.

I am definitely concerned about the converter, I think adding gear to the car will simply band-aid an inefficient converter (though I am far from experienced enough to make definitive judgement), and the issues I am facing now will continue to plague the car, as I turn the power up.

 

What is your idle RPM? Those cooler pressure readings seem really low, even at idle. Also, seeing a main line jump of 60-70 psi from idle to 2000rpm indicates a leak somewhere that the pump can’t offset until its volume goes up with RPM.

 

850 rpm. The pressures increase with any increase in RPM from idle. It is a new/reman pump (doesn't mean it was machined correctly I guess, was aligned in the case upside down and torqued to spec during reassembly after converter restriction), new seals on all apply pistons, new teflon sealing rings, flat sanded servo cover with new gasket, flat sanded valvebody area with proper gaskets used with the valvebody and plate, pickup tube was tight fit, and with pan off, installed in car, it has good enough seal that the tube stays filled with fluid (plastic tube, can see the fluid in it), metal screen type filter.

Perhaps I missed something during air checks? I didn't check the line pressure with cold fluid, but the converter pressures are about 60 PSI cold at idle, and drop down as temp increases, fluid is about 160* F when the cooler pressures get into single digits at idle.

Does anyone have an opinion on the gearing Vs. converter? Is it possible to change the slip % without drastically altering the RPM drop on shifts, or are they directly related? They basically told me with a 28" tire and 3.27 gears there is no getting around a high slip number, but I'm not sure I buy into that just yet. It is a 9" converter with billet front and mechanical diode.

 

My line pressures are the same at a 850 rpm idle as they are at any other RPM.

Gear ratio will hugely affect the converter slip. Are you just measuring the slip percentage going through the traps or do you have a driveshaft speed sensor to monitor slip all the way down the track. If you monitored the driveshaft rpm you will likely see that the slip percentage goes down into the single digits at the top of 2nd gear, but in third gear its just laying on the stall speed all the way through the traps because of the gear ratio. The converter can't couple until the driveshaft catches up to the engine rpm, which there is no way that is going to happen with the power your making and a 3.27 gear with a 28 inch tire. What are your goals for power and trap speed, and what rpm do you want to go through the traps at?

 

Slip is being calculated as RPM through the traps. Looking at the data logs after a shift it seems to spend about 3 tenths until RPM starts climbing again, definitely not sitting on the stall all the way through 3rd. After comparing the time spent in 3rd to my timeslip, looks like I cross the 1/8 near the top of 2nd with slip in the single digits.

End goal is 155-160 mph and undecided on RPM just yet, I won't know for sure until after I make some changes to the engine down the line and see what the different set up likes, likely at 7000, maybe a little higher. When I chose the gearset I assumed 7k with 10% slip and 28" tire.

This morning I found a conversation that Dusty Bradford had here on YB a little while back, and he said that the exact converter core I have he would never spec for a turbo v8 car, because they always have too much slip in high gear.

 

If you expect to run the motor through the traps at 6200 rpm, you best accept slip numbers in the double digits.


Hutch