ecotec swap

the trans i put in is a 944 turbo s AOR trans, the strongest 944 trans built. its been further modded with a rear stiffening plate and upgraded cooler. they are supposed to take a decent amount of power.

well, it wasnt the end of the world. pulled the trans back out today, got the end plug out and found no oil whatsoever at the rear mainshaft bearing, just a bunch of dry metal shavings. after getting the rear housing off i found not much oil in the back around 5th gear. after disassembling the bearing i found it had piled the cage up between the balls and the outer race. at least with the lack of oil the metal stayed in one place, there was no shavings in the oil i drained.

all i can really come up with is that when i ran the car in gear it filled the cooler and left the rear dry, although i should have at least had oil residue in the back end. i had wanted to fill the cooler up with oil before i put the trans in but the oil didnt show up in time.

worst part is i was unable to find that bearing, tried the porsche and audi dealers and they both laughed at me. i ended up pulling the back of the old trans apart and stealing the bearing, it looked to be in good shape. could have ordered a new bearing for next week, but i really didnt want to wait a week, nor do i want to pay $300 for a dam bearing. cars all back together and the trans seems to be fine.

that's pretty good news and doesn't sound catastrophic. i was offered $100 for my entire lightly used 944 turbo trans a couple years ago. so $300 for just a bearing seems a little ridiculous. did you try ebs racing? i've bought lots from them and they seem to beat the price on all the others... pelican, vertex, paragon.. for most things.

so how much oil came out of the system? did you flush and back flush? i hear the cooler works as a sort of a filter if it is similar to the oil cooler in air cooled 911s.

when refilling, is there a valve that allows oil to flow when certain temp or is it always in open oil cooling mode?

the 944 turbo transaxles typically sell from $500-1200 usd, depending if its a limited slip and/or has the oil cooler system. a 944 turbo s transaxle typically sells for $1500 usd, however the price seems to be going up, ive seen a couple listed around $2500 lately.

the oil cooler system on these transaxles is very simple, it has a pump driven off the diff and it has a cooler loop, basicly just some tubing with fins on it and it enters the rear of the transaxles. its not used for pressurized lube, just cooling. ive changed the system to a stacked plate cooler with fans. there is no thermostat, it flows oil all the time. its not really an issue, these transaxles are known for running hot, ive read about the ones with an lsd and no oil cooler reaching 250*f on a warm day with spirited street driving, and getting well over 300*f on a track.

a cooler doesnt act as a filter, rather it gets material trapped in it. i was lucky in a way, the rear bearing got no oil at all, so none of the metal got into the oil, in fact the oil looked like brand new when i drained it.

moved along and did some more work. got the front splitter properly mounted. i only had it attached with sheet metal screws, now its securely bolted, and got some trim clips around the bottom of the bumper.

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one thing the splitter will help solve is my slight cooling issue. one thing i found is it always ran around 200*f just cruising around. the fan would drop it down a little bit, but even when driving on the highway the temps would creep up and till the fan came on and dropped the temp back down. its pretty clear its suffering from a lack of airflow over the rad, and the rad fits fairly far back from the bumper. my old splash shield didnt fit after the swap, so a lot of airflow through the bumper was being lost before it went through the rad, the splitter fixes this issue. the other half of this is the top, there is a large open space spilling air over the rad. i templated out a cover, didnt have any material to make it but at least the design work is done.

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it work out how i really wanted it to, the linkage for the pop up headlights forced me to push it higher up that i wanted. i had wanted to follow the profile of the hood latch bracket but it just wasnt going to work like that.

gonna try and get my washer fluid tank installed finally. i dont have too much more i want to get done before we get the car on the dyno and figure out if we still have an rpm signal problem or if thats fixed. ive got a number of things i want to get done, like rebuilding the rear suspension, i just dont want to spend the money there till i know i have a properly running car.

in the mean time, here are some pics of installing the trans. the old greaseball

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back of the torque tube
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finally something went right today. i figured today id put the car back in storage, instead i got told if its ready, put it on the dyno. so right off the bat the rpm glitch issue is sorted out. not sure if it was the ecm causing the problem, or weather the crank sensor gap was too tight before, but on the first pull it went right back to 290hp. in the end, well, here is the chart

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414 hp, that was at 18psi, only running around 17 degrees timing, and reving to 8000 rpm. needless to say i havent stopped smiling. im working on editing some video right now.

here is some quickly hacked together video

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i love that... having a dyno nearby when you least expect it!!

engine sounds great, with the turbo whine and not overly loud exhaust.

at what rpm does the torque spike up. looks like little or no lag.

good job!

the pics posted yesterday don't come up for me...

we couldnt get a stable rpm signal on the dyno, so we wernt able to measure torque. ill have to grab the dyno sheet from the 3rd gear pulls and i can figure out when the turbo was fully spooled. it does have turbo lag, its 57mm turbo, on the large side for the application.

more one step forward, 2 steps back, kind of. when i plugged my ecm in last week i had a high idle, around 2200 rpm, essentially the idle solenoid wide open. wasnt too concerned at the time, figured it was in the tune. when we tried to turn it down, well it wouldnt. we just restricted it for the time being and kept on tuning. looking into it some more and the end result is the ecm is grounding the idle solenoid all the time, including when the key is off. thinking i had something causing it i went through the wiring and found nothing, and when i unplug the ecm the circuit goes open. so it looks like the ecm has an internal short to ground causing the problem.

seeing how i want to drive my car this year and dont want to be without the ecm for another 5 months i set the idle on the throttle body and pulled the idle solenoid off. so far ive only cold started and run the car for a little bit, im hoping through the temp range the idle wont be off too far. dont really want it struggling to idle cold and idling too high when hot, but ill see what happens.

onto other things i decided im going to give the rear suspension some love. i got looking at it last week and the trailing arm bushings are soft, the spring plates are off to one side of the torsion tube caps, and the back of the car always had a "squirmy" feel when cornering hard. i was hoping to do a complete rebuild of the rear suspension all in one shot, including blasting and powder coating everything, along with deleting the torsion bars and running coilovers, m030 968 swaybars, etc. well, thats not really in the cards right now. for the time being im going to put in the polybronze spring plate bushing kit, spherical trailing arm bushings, and solid lower torsion tube bushings. i had a hard time justifying the cost of the solid upper torsion tube mounts, but i found some info about turning the factory rubber mounts into solid ones with nothing more than a welder and some fire.

id love to find a cheap set of stiffer torsion bars, my car has the 2nd weakest ones used in a 924/944 (23mm). the car being lighter on the front end (by my best guess around 100lbs) and having 200 lb/in lowering springs, the car is a little unbalanced. not gonna worry about it too much, im going to put coilovers and big swaybars in at some point, would just be nice to have for now.

i struggled for a good part of a year with idle issues. on my 911 so totally different beast.

running all stock i went through a set of wires, plugs, rotor, caps then looked into my idle air control valve... turns out it was timing and indexing my distributor. i think you are running coils off the ecm.

then had some lumpy idle and was checking oil in the evening and found the spark was arcing at the top of the distributor cap, replaced and got all my power especially top end over 5500 rpms back. remember i have the twin plug with dual distributor on the 964. then the car would either idle high (3,000 rpm) or stal coming to a stop sign. i found the throttle cable (are you drive by wire?) was frayed and hanging on by 4 tiny threads and replaced the wide open throttle / idle switch. cars idles and drives perfectly now.. even after my complete rebuild!

then ran into similar problem with my e46 m3. i had misfire and cel light up my dash with rough running. checked my coils and spark plugs as the car is new to me. went online and found it was the vanos or variable valve timing coil pack. pulled it out, took to my solder geek friend and six hard ciders later, problem solved! also saved having a disabled m3 while waiting for parts to ship, fix and return. the coil pack on the m3... $729 USD (of course) from ECS tuning. or $150 to a Beisan Systems. Very helpful!

hope you can solve that issue.

regarding suspension i think guys run 400 to 800 lb/in springs on the 944s depending on what you plan to do with the car. track or more street. either way stock setup allows for way too much sway and overly soft ride... i have video of me following my buddy both in 1985.5 bone stock 944s on track in Toronto area. total blast and very slow but... really fun which is all that matters to us old guys.

the only issue with the idle is that circuit in the computer to control the idle air solenoid is shorted to ground all the time. makes sense why the car was killing the battery overnight. only fix would be another trip to australia for my computer and thats not going to happen. ill just deal with not having idle control, its not ideal but i just want to drive the thing.

still waiting for my rear suspension goodies to ship, but i started really looking into the torsion bar thing. i was hoping to find some cheap used ones, however it seems anything used thats not the common 23.5mm is almost as much as new swayaway bars. what i did find is that a company called California Import Parts has some options for torsion bars for various vw stuff, and found some people online running them in the 944 with good results. best part is they are less than half the price of the swayaway bars. even better is the company is local to me, so no shipping costs.

after a bunch of research i settled on 27mm bars. many people said with 220lb springs to go with 26mm or 27mm bars, my springs are a little weaker at 200lb, but the front end is a little lighter than stock. this should help balance the car out a bit, and im hoping itll be alright with the bilstein shocks that are on it.

after much frustration i finished off my rad cover piece today.

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actually the frustrating part was the fact i had it all bent up and partially attached only to find out the headlight mechanism hit it. i didnt really want to start over, so after a few days of ignoring it i just put a couple slots in the top to let the mechanism poke up through as it rotates. so many times with this car ive been on the edge of ordering a fixed headlight kit, but i then i think, what kind of 80s sports car would it be without pop up headlights?

suspension goodies are finally here

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racers edge trailing arm monoball bushings and solid lower torsion tube bushings, along with elephant racing polybronze spring plate bushings. i elected not to go with the aluminum torsion tube mounts, i found some info on turning the factory mounts into a solid mount, its quite an easy thing to do so i decided it would be a good place to save $240.

Sharkey. Love the build. I have been following your progress. I like your lower rad mount unit. I may duplicate. that would help me with mounting my rad but also my new nose of my car. Keep it up gives me insperation.

ive had it brought to my attention on another forum that people were having issues seeing my latest pics. i think i have it sorted, however let me know if images arent showing up.

been plugging away at it some more, this is taking me way longer than i thought it would. i spent yesterday media blasting and cleaning everything, and managed to get everything painted.

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here you can see the polybronze bushings installed in the torsion tube and the end caps. grease fittings have been installed in the torsion tube and end caps to allow them to be greased without having to pull the whole car apart.

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and here it is bolted together ready to go into the car.

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indexing the torsion bars is a pain in the ass, i see why people go to coilovers lol. i found a calculator and how to on spec944.org for doing it, it uses measurements from the ground to center of torsion bar with the car on the ground and with the car lifted till the tire just comes off the ground. it calculates how much the old torsion bar rotated for ride height, and with the diameters of both the old and new torsion bar sizes it gives you how much rotation the new torsion bar will have at ride height, and gives you how much shorter the distance should be between axle centerline and the torsion tube support bar. it spit out 1.75" less on that dimension, so thats what i set it up at, ill find out tomorrow when i put it in the car and set it on the ground. im fully expecting to have to pull the car all back apart to re index them again, but i think the 2nd time should be easier.

Ahhh yes, pics are coming through properly now. I thought it was just my computer, good to know.

As for indexing the torsion bars, that's part of what's kept me from cleaning my rear suspension up like that. A friend and I put in 28mm bars before my last few track runs this summer and didn't pull it back out to clean once it was mocked up because he guessed right and it was sitting nicely. Those pics are inspiring me to take another shot at it though. Lookin' good!

JP

Looks real sharp. I will be doing the same. My bonus no torsion bars.

jpkinerk wrote:Ahhh yes, pics are coming through properly now. I thought it was just my computer, good to know.  

As for indexing the torsion bars, that's part of what's kept me from cleaning my rear suspension up like that.

if your not changing torsion bars its not the end of the world, all you need to do is take out the whole assembly and measure between the top of the torsion tube arm and axle centerline and put it back to that. if you want to change ride height just add or subtract how much you want it to change from that measurement. its just when your changing torsion bars is when things get interesting.

i realised yesterday i didnt post any pics of the solid mounts i fabricated. this is the mount you start with, i had already tourched it apart and blasted the bracket when i took the pics

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and after a couple pieces of angle iron, a couple bolts and some welding

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simple way to save $240.

the car is almost back together. i ended up putting the suspension back in the car just enough to get the wheels on and set it on the ground to find it was sitting 2" too low. i either measured something wrong or that calculator doesnt actually work. i had so much faith in it i didnt put half the bolts in everything before trying it. pulled it all back out and apart, reclocked the torsion bars on the bench again, put it all back together and ended up with the car not quite 1/2" higher than it did before. i figure the torsion bars will sag a little so its not a big deal, and i do have the height adjustment cams i can play with. ended up getting most of it together today, i started to assemble the parking brake shoes only to find i lost a little pivot pin for the actuator mechanism. i ended up having to make one myself as hardware kits for these parking brakes is non existent.

all ive got left is to finish the brakes and bleed them, a quick "oil can" alignment and back into storage it goes, at least till the weather gets nice.

its all done. did a quick rip around the parking lot, it feels totally different. its sitting a little higher in the back than id like it, im hoping itll settle, but if it doesnt i should have enough adjustment to bring it down where it needs to be. itll get an alignment once it comes back out of storage, i was too worn out today to spend any time on getting it closer.

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im starting to think about stiffer sway bars. been looking at the 968 m030 set, however ive got some other ideas as well.

Looks great. You did a really good job on it.

we had great weather the past few days, so i decided i was gonna dig the car out last week. well, one thing turned to another and i wasnt able to on the weekend, then i went to get the permit on monday to bring it home and couldnt find my registration papers, and then it rained today, so the car still hasnt moved.

after many many hours of research and a couple weeks waiting, some of my swaybar stuff showed up today

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those right there are nascar/late model hollow splined sway bars from speedway engineering, and some unknown brand of aluminum arms with steel spline inserts.

it took me a long time to sort out spring rates for the sway bars, i had to figure out roughly what spring rates the bolt in options were, and sort out what size bars to go from there. the options for what you can do with these types of sway bars is limitless, companies will make any length bars you want, in any diameter. off the shelf stuff almost limits you to a 37.5" long bar, but you can have diameters from 0.400" all the way to 2 5/8", and available in solid or hollow. the best part about being able to go with an off the shelf bar length is the cast off race parts. there are tons of these sway bars on ebay, some of the bars costing as little as $50. arms are a little harder to find used, new they come as a splined arm blank, usually in steel, and usually they get bent to a shape that works.

i ended up going with 1-1/4" 49 spline bars, meaning the bushings are 1-1/4" and the bar is cut down in between the bushings. i went with the smallest bar they make for the rear, a 0.910" and the front is a 1.180" bar, and they both are a 0.750" drilled center. with the length of the arms im running these sway bars will end up being softer than the 968 cup bars, however my overall suspension setup is softer overall than most people run with those bars so i think itll work well. the nice thing is once they are in the car, if the bars are the wrong size they are easy to change, and fairly cheap to buy.

once im able to mock some stuff up ill need to order some heim joints for the links and another set of arms. the arms i got for $50, ill end up having to cut them down significantly, and in reality i dont even know what end of the car they will go on.

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its back home finally. its been almost a year since ive driven it, went for a bit of a drive and i remember why i loved the thing so much. the suspension changes i made were well worth it, and although i havent gotten an alignment yet, but its amazing how much more planted the car is. the car used to go into a corner nice, and then would unsettle as the old rubber bushings deflected, im happy to say thats all gone now. im happy with the size torsion bars i went with, the car feels neutral with no hint of oversteer. im looking forward to getting the sway bar setup built as the car does still have a fair amount of body roll.

power is insane in a car this light. yea, its got turbo lag, but man when it spools does it ever pull. its a little weird cause im trying to get used to the steeper final drive ratio in this turbo transaxle. the ratio isnt the best for a  high strung 4 cylinder, but id rather have the power holding capabilities it brings. the good thing is first gear is actually usable, rolling into the throttle and it doesnt hardly spin the tires, and just a little squirmy after shifting into 2nd gear, just hooks and charges.

i do have a list of things i gotta tackle though. i started the day off with a stuck open thermostat, couldnt get the car past 140*f. after driving in some traffic it finally got to 180, but it kept dropping from there. the never ending brake saga continues, i figured they would take a while to get some bite again, but after a pile of heavy braking they suck as bad as ever, and i dont get any smell. i adjusted the bias way to the front and it really doesnt add any front braking power.at minimum im gonna pull the front calipers apart, i might have a sticking piston, but with the problems ive had im thinking its wisest to just ditch them and go with something else.

Every time I drive one of these cars with real power, I'm just amazed at how much fun they are.

Good job on your build.

thanks.

talked to the guy at carbotech today about a set of brake pads. i initially figured on the ax6 compound, but after talking to them they recommended i go with the xp8. im going to do some track day stuff in the future, and even as a novice driver he figured i could overheat the ax6 pads. so im hoping these do the trick, they are bloody expensive, but will be well worth it if they are the answer.

i did get the thermostat checked off my list yesterday. didnt see anything wrong with the old one, im gonna guess after i drove the car home it unstuck and closed again.

We use Carbotech pads exclusively on our race cars. Amazing pads and customer service is great.
Prices are lower than what we were paying for Performance Friction and Pagid. But yeah, good pads aren't cheap.