so i bought a porsche.......
01-20-2017, 08:45 PM
#226
been slowly picking away at this. i started checking the diff setup and found a major issue, the pinion shaft bearings had around .003" of backlash, where they should be somewhere around 5-10 lb/in of preload. it appears at some point in its life it was set up incorrectly. i didnt find any excessive wear on anything or signs it had been apart before, so its possible it was wrong from porsche. one of the theories of why the case breaks (where the stiffening plate ive added goes) is because the pinion gets backlash and hammers on the rear case everytime you get on the throttle. guess there may be some truth to that. i had added a .006" shim to get it where i was happy.
got few other things checked off on the list. i drilled and tapped the cooler return hole in the main case section.
i also made the fittings to go into the factory oil return and the pump. quite simple, i just used a couple off the shelf -8 and -6an fittings and machined them down. this is one of those times i really like having my benchtop lathe. best $350 i ever spent.
im going to run a fan temp switch to turn the oil cooler fans on and off. initially i thought our drain plug was just 3/4" npt but later found out it was metric. i decided to just drill and tap the factory drain plug for my fan switch, it actually worked out pretty well
last thing i machined up some longer dowel pins for the rear cover. from what i can see, most people seem to skip this when adding the stiffening plate and just run the cover unindexed. i dont like this idea, so i did it properly
so now that i have everything sorted out ill be sending the case out to sand blast and ill be powder coating it before i assemble it.
got few other things checked off on the list. i drilled and tapped the cooler return hole in the main case section.
i also made the fittings to go into the factory oil return and the pump. quite simple, i just used a couple off the shelf -8 and -6an fittings and machined them down. this is one of those times i really like having my benchtop lathe. best $350 i ever spent.
im going to run a fan temp switch to turn the oil cooler fans on and off. initially i thought our drain plug was just 3/4" npt but later found out it was metric. i decided to just drill and tap the factory drain plug for my fan switch, it actually worked out pretty well
last thing i machined up some longer dowel pins for the rear cover. from what i can see, most people seem to skip this when adding the stiffening plate and just run the cover unindexed. i dont like this idea, so i did it properly
so now that i have everything sorted out ill be sending the case out to sand blast and ill be powder coating it before i assemble it.
Moderator
01-22-2017, 11:01 PM
#228
everything is cleaned up and masked for media blasting now. with that all taken care of i decided to tackle the diff.
all i did with the lsd was inspec it and change the external splines plates from the 2.0mm to the 2.1mm thick plates to add some more preload. i reused the internal splines friction plates, they were still just as thick as new so i decided to save the $100. i also put in a new set of diff bearings just for good measure. the end result with the thicker external splines plates was the break free torque going from 32 lb/in stock to 125 lb/in.
all i did with the lsd was inspec it and change the external splines plates from the 2.0mm to the 2.1mm thick plates to add some more preload. i reused the internal splines friction plates, they were still just as thick as new so i decided to save the $100. i also put in a new set of diff bearings just for good measure. the end result with the thicker external splines plates was the break free torque going from 32 lb/in stock to 125 lb/in.
02-07-2017, 06:54 PM
#230
i didnt take many pics while putting it back together, aside from one small detail. i meant to, but i got a little frustrated once i got everything in the center case and discovering i forgot to install the reverse detent in the back of the case, one of the first things you have to do.
now for the small detail. i discovered while assembling it that the gasket set didnt come with the o-rings or oil pump gasket. figured no big deal, ive got o-rings and the ill just silicone the pump cover. turns out the pump binds up without the gasket. i only found one place listing online (cogscogs.com) but after ordering it i got an email back saying its no longer available. there were 2 different options for it, a 0.20mm and 0.15mm, im hoping just the one i ordered is nla and the other isnt, but im not holding my breath. im going to have to track down some very thin gasket paper and try and cut my own.
now for the small detail. i discovered while assembling it that the gasket set didnt come with the o-rings or oil pump gasket. figured no big deal, ive got o-rings and the ill just silicone the pump cover. turns out the pump binds up without the gasket. i only found one place listing online (cogscogs.com) but after ordering it i got an email back saying its no longer available. there were 2 different options for it, a 0.20mm and 0.15mm, im hoping just the one i ordered is nla and the other isnt, but im not holding my breath. im going to have to track down some very thin gasket paper and try and cut my own.
04-23-2017, 01:05 AM
#234
got a little work done the past couple days. since i finished the transmission i havent done anything with the car. my health hasnt been improving much, im still off work and will be for the foreseeable, and i was pretty much content with the idea of not putting the car on the road this year because of it. at least that was till a good friend of mine pointed out that i should at least enjoy the car a little more before i go for surgery.
so with that in mind im trying to get the biggest gripe with the car sorted out, and thats the brakes. ive been fighting issues that stemmed from major bias issues the entire time ive been driving it. the solution is to ditch the tandem master cylinder and go to a dual master cylinder setup with a balance bar. ive had the stuff for a long time but i just havent gotten to it. the weather was nice enough i was able to pull the firewall plate off on friday and i got the bracket fabbed up.
still need to weld it up, enlarge the hole so i can fit the boot for the pushrod, and remount the line lock solenoid. then off to powdercoat, redo the brake lines, bleed brakes, and that project is done. should only take me another month at the rate i move lol.
so with that in mind im trying to get the biggest gripe with the car sorted out, and thats the brakes. ive been fighting issues that stemmed from major bias issues the entire time ive been driving it. the solution is to ditch the tandem master cylinder and go to a dual master cylinder setup with a balance bar. ive had the stuff for a long time but i just havent gotten to it. the weather was nice enough i was able to pull the firewall plate off on friday and i got the bracket fabbed up.
still need to weld it up, enlarge the hole so i can fit the boot for the pushrod, and remount the line lock solenoid. then off to powdercoat, redo the brake lines, bleed brakes, and that project is done. should only take me another month at the rate i move lol.
04-23-2017, 01:29 PM
#236
yes and no, its a little more complex than 2 masters because manual brakes. your average braking system has a tandem master cylinder, one master cylinder with 2 separate circuits. with a factory designed braking system is designed in a computer with vehicle dynamics all worked in so it gets the brake bias bang on. when you start swapping brake components (larger rotors, different calipers) it throws the bias off, sometimes an adjustable bias valve is the answer, sometimes it doesnt work well enough. often these issues are masked in a power brake system, and the bias is too much front, something that most wont really notice.
now in a manual brake car brake bias problems are amplified. with a tandem master cylinder both pistons move at the same rate, and max input pressure is reached at the same time, and the output fluid pressure can vary front to back. in my case i was reaching the max pressure of the rear system first and the front brakes just arent doing their job. ive calculated my brakes to need a 1" bore master cylinder for the rear and 13/16" for the front. i could have searched around for a step bore master from something factory, but they are not common, and as ive read many times, calculating master cylinder size usually gets you in the ball park but once you ad in vehicle dynamics you may need to change it.
here is where the dual master cylinder setup comes in. instead of having the 2 cylinders built in one body like a tandem you have 2 that you can service separately. they hook together with a balance bar to the pedal. the balance bar basicly allows you to change the distance from the pedal input to the master cylinder pushrod, changing the brake bias on a mechanical level instead of hydraulicly. if i have to adjust it too far one way to get the bias i want, i can simply just replace one master cylinder. the balance bar also allows the master cylinders to move different distances. my front calipers need more volume than the rear, but i have a smaller bore master in the front (smaller bore size will create more hydraulic pressure with the same pedal pressure) so the front master will need compress more than the rear. you can see in the first pic how the balance bar is at an angle and one pushrod is longer, that will get set so with functioning brakes at half travel of the masters the balance bar is straight to the mount, and at hard braking the bar will actually angle the other way.
typically this sort of stuff is used on race cars, but with a manual brake car thats in no way stock, its needed to make it work correctly.
now in a manual brake car brake bias problems are amplified. with a tandem master cylinder both pistons move at the same rate, and max input pressure is reached at the same time, and the output fluid pressure can vary front to back. in my case i was reaching the max pressure of the rear system first and the front brakes just arent doing their job. ive calculated my brakes to need a 1" bore master cylinder for the rear and 13/16" for the front. i could have searched around for a step bore master from something factory, but they are not common, and as ive read many times, calculating master cylinder size usually gets you in the ball park but once you ad in vehicle dynamics you may need to change it.
here is where the dual master cylinder setup comes in. instead of having the 2 cylinders built in one body like a tandem you have 2 that you can service separately. they hook together with a balance bar to the pedal. the balance bar basicly allows you to change the distance from the pedal input to the master cylinder pushrod, changing the brake bias on a mechanical level instead of hydraulicly. if i have to adjust it too far one way to get the bias i want, i can simply just replace one master cylinder. the balance bar also allows the master cylinders to move different distances. my front calipers need more volume than the rear, but i have a smaller bore master in the front (smaller bore size will create more hydraulic pressure with the same pedal pressure) so the front master will need compress more than the rear. you can see in the first pic how the balance bar is at an angle and one pushrod is longer, that will get set so with functioning brakes at half travel of the masters the balance bar is straight to the mount, and at hard braking the bar will actually angle the other way.
typically this sort of stuff is used on race cars, but with a manual brake car thats in no way stock, its needed to make it work correctly.
05-03-2017, 12:08 AM
#239
brakes are now checked off the list. i got everything installed last week and finally had the energy today to bleed them. after fixing an issue with the front calipers ive got a solid and consistent pedal, something i havent had since i put the car together.
now onto a few other things before i can fire it. need to make a mod to the intake manifold to properly mount my idle air solenoid, and adding a dsm pcv valve into the valve cover.
now onto a few other things before i can fire it. need to make a mod to the intake manifold to properly mount my idle air solenoid, and adding a dsm pcv valve into the valve cover.
06-03-2017, 07:02 PM
#240
got my transmission cooler mount built this week. i ordered this cooler from summit, going off the listed dimensions i would have been able to put it where the factory cooler sat, mounting it off the bellhousing. turns out the dimensions were wrong, and ive had this thing for months, so no returning it, so i just made something work.
its in a less than ideal location with no direct air flow. looking at the factory cooler and a few options other people have done, it doesnt seem to be a big issue. the 2 fans pull a lot of air across the cooler so i think it will work alright. plumbing it will be a little interesting, however ive found some low enough profile fittings to get it done.
its in a less than ideal location with no direct air flow. looking at the factory cooler and a few options other people have done, it doesnt seem to be a big issue. the 2 fans pull a lot of air across the cooler so i think it will work alright. plumbing it will be a little interesting, however ive found some low enough profile fittings to get it done.
06-13-2017, 01:47 AM
#243
finally put the car on the road for the summer. i got a few more things done last week and decided it was time. the trans cooler fans are all wired into the car so when the trans goes in its all there. wired in an led so i know when the fans are on. that snowballed into fixing my gauge cluster, a sticker on the inside of the cluster fell off and was sitting on the speedometer needle. also fixed the stupid factory lighting system for the cluster. i gotta actually put a picture up of this to show the stupidity
so the lights are in the back of the cluster, and clear plastic things are "light channels" that conduct the light to the front side of the cluster. originally they were covered in a reflective coating, the one on the left is the remnants of that, the others have been cleaned up. what happens here is the "light channels" just shine light under the dash and the cluster is dim as hell. and a stupid fix for a stupid design, glue tin foil shiny side down to them, this keeps the light in the channels. the fix does work, with new silvania 4 watt bulbs the cluster is nice and bright now.
also got my "new" tires mounted. lucked out and found a set of almost brand new continental dw extreme in 255/40zr17 for the back for a real good price. didnt luck out so good on front tires, but i got some dunlop sp 225/45zr17 with decent tread, but they are a bit old. price was right though. would have liked to put a brand new set of some sticky falkens or michelins on it but its just not in the budget right now. after a spin around the block i had to roll the fender lips on the rear, tires are a little close to the opening. i wasnt going for fitment, but i seem to have gotten their on the back. fronts could come out a full inch though.
so much fun driving it again. still getting the brakes dialed in, they are getting a lot better, i may have to change to a smaller front master cylinder, and im on the fence on the ebc redstuff pads. i dont seem to have much initial bite, but im able to haul it down fast enough to lose oil pressure momentarally (looks like i need to add baffling the oil pan to the list). still only running 8-9 psi at the moment, with the new tires on the back it sticks enough in 1st gear to be scary, when it hits full boost the steering gets noticeably lighter.
cant wait to get the new trans in and turn it up.
so the lights are in the back of the cluster, and clear plastic things are "light channels" that conduct the light to the front side of the cluster. originally they were covered in a reflective coating, the one on the left is the remnants of that, the others have been cleaned up. what happens here is the "light channels" just shine light under the dash and the cluster is dim as hell. and a stupid fix for a stupid design, glue tin foil shiny side down to them, this keeps the light in the channels. the fix does work, with new silvania 4 watt bulbs the cluster is nice and bright now.
also got my "new" tires mounted. lucked out and found a set of almost brand new continental dw extreme in 255/40zr17 for the back for a real good price. didnt luck out so good on front tires, but i got some dunlop sp 225/45zr17 with decent tread, but they are a bit old. price was right though. would have liked to put a brand new set of some sticky falkens or michelins on it but its just not in the budget right now. after a spin around the block i had to roll the fender lips on the rear, tires are a little close to the opening. i wasnt going for fitment, but i seem to have gotten their on the back. fronts could come out a full inch though.
so much fun driving it again. still getting the brakes dialed in, they are getting a lot better, i may have to change to a smaller front master cylinder, and im on the fence on the ebc redstuff pads. i dont seem to have much initial bite, but im able to haul it down fast enough to lose oil pressure momentarally (looks like i need to add baffling the oil pan to the list). still only running 8-9 psi at the moment, with the new tires on the back it sticks enough in 1st gear to be scary, when it hits full boost the steering gets noticeably lighter.
cant wait to get the new trans in and turn it up.
06-29-2017, 12:07 AM
#247
i recently started running into some fueling issues. shortly after i originally put the car on the road last year i had a fuel pump failure, or so i thought. i was running an aem 380lph pump, basicly a higher output version of the bosche 044. i started getting the same fuel pump squealing noise with a genuine 044, along with going lean under boost. i opened my billet fuel filter up to have a look, only to find it doesnt actually have a cartridge in it, just a round disc under 1" in diameter. it had some trash in it, so i cleaned it and problem solved. i ended up putting a different filter on, its from performance world, and its basicly a knock off of an aeromotive filter. its got a large cartridge, fuel flow is no longer an issue.
it appears the fueling restriction has been an issue since day one as after the filter upgrade the engine is going dead rich under boost now, talking in the range 10.0:1, and it just starts misfiring. im guessing when it was tuned the fuel flow wouldnt keep up under boost and as a result fuel pressure wasnt increasing as it should. as a result the fuel map was richened to make up for it. now that i think back, i remember my fuel pressure gauge bouncing when it was on the dynos, i figured it was just because it was a non liquid filled gauge.
so long story short, the car goes back on the dyno friday. likely will tune it for high boost, just wont be able to run it on high boost on the street till i get the transmission swapped (at least not unless i want a tow bill).
it appears the fueling restriction has been an issue since day one as after the filter upgrade the engine is going dead rich under boost now, talking in the range 10.0:1, and it just starts misfiring. im guessing when it was tuned the fuel flow wouldnt keep up under boost and as a result fuel pressure wasnt increasing as it should. as a result the fuel map was richened to make up for it. now that i think back, i remember my fuel pressure gauge bouncing when it was on the dynos, i figured it was just because it was a non liquid filled gauge.
so long story short, the car goes back on the dyno friday. likely will tune it for high boost, just wont be able to run it on high boost on the street till i get the transmission swapped (at least not unless i want a tow bill).
06-29-2017, 01:48 AM
#249
i dont tune this myself, although i tuned this engine when it was running a megasquirt. i havent really learned the microtech yet, but the biggest thing is i have a professional tuner with 20+ years tuning experience with a dyno that tunes it for free. i do want to learn the microtech some more, i played around with it to get the car running and my tuner took over from there.
honestly right now if i knew the system better id trim some fuel out and not worry about strapping it to the dyno.
honestly right now if i knew the system better id trim some fuel out and not worry about strapping it to the dyno.
