Ok, I stopped procrastinating and have ripped the diff out. So glad I didn't have to do that at a wreckers so thanks again VR4retrofit for the donor diff and 81GL for the already removed arms!!! No turning back now!
I would have bolted the Scorpion housing up but I need to get some new bushes for the arms so that will have to wait. Hopefully checking out an already done Scorp/GK Sigma diff setup tomorrow so will have more of an idea on what I have to do to finish the job. Also lined up getting the L300 centre locked for track use so it's all coming together. I didn't have a chance to bleed the air out of the radiator but will suss that out when the car is rollin again
Diff done! Long story short - still needed a heap of brake bits so bought whole Scorpion off Ebay and swapped whole lot! Ended up putting the Sigma diff back in the Scorpion so it was moveable too. Big job but really happy with the result - the Sigma now has a GK Scorpion diff with locked 4.6 L300 Centre . A few more little things and she is ready for the track . Thanks to GB_BB4C for his help with the handbrake cables the other day too - was the last thing needed and I couldn't quite get it done!
Unplanned mod - Tail shaft loop required for 1/8 mile drags coming up. Installed this yesterday :
Now hopefully I can stop lying under the thing and work on some stuff standing up. Trying to rig up a heat shield for the Turbo at the moment, then will give all the mechanicals a once over and look at that air in the cooling system theory. I backed the car out onto the street yesterday too - I'd forgotten what a pain lockers are for normal driving!
What model L300 did you get the 4.6's from? Year? 4WD/2WD?
The reason I ask is 4.77:1 seems to be a good match for a 20v 4AGE, which makes about the same torque as a stock injected 2.6. It'd probably be nasty on the highway, but skating 3rd with a stock engine sounds mighty appealing to me
-Josh.
Daily: 7/96 EF Falcon, 4.0 SOHC, BTR95LE, 3.45:1 LSD/Lukey extractors, full 2.5” exhaust, EL intake, Tickford snorkel, 87DA cam, AU injectors, shiftkits.com.au single stage kit. PB 14.93@91mph.
Project: Red '81 Scorpion-http://www.sigma-galant.com/viewtopic.php?f=46&t=11889
The diff in the car now came from the Scoprion I wrecked so I can't confirm the exact origins. The spare open wheel centre I have came from this:
2WD, square headlights. Not sure of the model/year though. I'd offer to sell the spare I have but I reckon I'll use that for street and keep the locked one just for the drags
Ha ha, if it's the Tailem Bend track day I'm trying to block it out! LOL. I'm hopefully going to make it on Sunday so I'll tell my sob story in person! Damian, can one of you guys maybe PM me the exact details of time and location etc. Jason, are you planning on going down at all?
Oh and seeing this is my build thread, check out this thread here:
It contains details of why my "build" now includes timing belt, balance shaft belt, clutch, and a few other bits and pieces! The poor thing is up on jack stands in a thousand pieces again :
I think so, the speed boat club has a practice day but I can't be arsed getting into the river at 8am.
Might go and hang out for a while, I think 84GKSIG is coming over sometime Sunday arvo
Big thanks to A112H - I now have the top Timing cover! I got the car running again yesterday after replacing pretty much all the front seals and the Timing Belt and Balance Shaft belt. I'm not very confident though - the belt seems a tad loose and the adjustment on the dizzy maxes out at around 7 degrees BTDC. I think I may be a tooth out, even though all the markers lined up when I put the belt on. Anyone ever done a belt on of these motors or a similar belt driven motor? When running, how much movement should the belt have? I'm going to pull it all apart again the next couple of days and try again as I want to be sure. I did so much research last week I'm confident the balance shaft belt is right.
The silent shaft belt should be tensioned up to allow no more than 5-7 mm deflection. The main timing belt deflection should be about 12 mm (measured by squeezing the belt in the middle of the longest section of belt towards the edge of the timing cover backing plate's inner lip). If you pull the distributor out and move it forward a tooth and it's too far advanced then I have a solution. Take out the distributor and rotate the rotor button til it's pointing directly opposite of the #1 alignment marker (180 degree rotation) and re-install the distributor leads making #4 fire as #1 then swap all leads accordingly. I ran into this problem once and it was infuriating to solve.
Thanks mate, very handy info! I think the shaft belt is within spec but I'll try out the Timing belt movement and check the dizzy tonight. Will update the thread with my findings .
Got to fill in some info I omitted. The measurement for the main timing belt deflection is 12 mm between the timing belt and the timing cover backing plate inner lip. Hope that isn't less confusing than my previous post!
All good mate, got my head in the bay right now with iPhone handy! The manual has a nice diagram and it has a very confusing 9/16 of an inch which works out to be 14 mm so close enough! So I think the belt is right and the timing marks line up. The manual actually ommits the timing setting. Does 5 degrees btdc sound right ?
To set up ign timing rough enough for it to run and then be correctly adjusted with timing light, turn crankshaft when it's at #1 tdc firing back to 10deg BTDC, then turn forwards to 5deg BTDC (this is factory spec, if you want to change it to whatever, principle still applies), remove dizzy cap and make sure when you insert he dizzy into the head the pointer ends up aligning to the number 1 plug lead spot, if it's close, turn dizzy to get as close as you can...bolt dizzy in place etc, this should be close enough to run fairly well....
Thanks for the tips guys. I pulled the belt off last night and sanity checked it all . I reckon the belt was slightly too loose. All the timing marks where right though I reckon. I put it all back together and gave it a quick run – the belt no longer moves so I have piece of mind now. Interestingly I printed the dizzy details from the manual at the library and then when I got home found it was pointless! On other cars like my Siggy Turbo, taking the rocker cover off has assisted in lining up the dizzy as there are marks on the cam etc. With the Sirius motor, the dizzy shaft/cog isn’t visible so I took the rocker cover off ( and a heap of crap that’s in the way like the inlet manifold extension and intercooler plumbing ) for nothing! The manual is quite funny – it basically says line the rotor button at number 1, mark the dizzy and block/head somehow, and try and get it back in the same spot. Ha ha, no exact science there! Tonight I’ll probably go over the rest of the stuff in the bay, make sure all is well, and then I can focus on the clutch. Slight chance I’ll be rolling on the weekend
So many hours spent in the shed . Finally was able to drive the car on the weekend after sorting out Gearbox and Clutch issues ( other thread : http://www.sigma-galant.com/viewtopic.php?f=24&t=7840 ) and have uncovered some more small issues that will see the car stuck in the shed for longer. The motor side of things is all good and the new belts and timing looks to be all sorted. I made up some heat shields out of galv so in terms of the engine bay I’m pretty much finished apart from a sticking accelerator cable. The car uses an L300 inlet and throttle body and the bracket that holds the cable is custom made and pretty average. I think I need to have another one made as the throttle gets stuck between 1500 and 3000rpm. Stabbing the throttle harshly fixes it but that’s not much fun in traffic as I found out yesterday.
The main problems I have now are in the rear end. Above 60 there is a low “growl” vibration that is present whether it’s in gear or not. Seeing I’ve replaced everything back there I’m going to have to go through a process of elimination to find the source of it. Yesterday I swapped axles and wheels and it not only didn’t sort the vibration, I think I may have dislodged one of the brake pad clips as the brake pedal is pulsing and the back right is squealing. The handbrake doesn’t work now too so more adjustment is needed. The Scorpion setup is so time consuming compared to the Sigma one! I’m thinking the cause of the issue may be the L300 diff centre I swapped into it ( the locked one at the drags seemed ok but with a helmet on, it’s hard to tell ) so I’ll probably pull that out and go from there. My goal of getting the car sorted for Heathcote next month is looking shakey with all these little problems!
Update on the Siggy. Still chasing rear end issues. I've now replaced the rear calipers and hand brake cables, tried different springs and shocks, and it's now got the locker back in it. The vibration seems better but now it looks like under load over bumps, the tail shaft is hitting the tailshaft loop bolts! I wouldn't have thought there was that much movement but I think I'm wrong! Will be hopefully sorting that out tonight. I still want to get to Heathcote drags soon so I think I'm gonna have to suck it up and replace all the rear suspension and bushes in order to solve the tramp issues and other stuff. Will try and get more pics up soon so the thread isn't just about me rambling .
In other news, I'm hopfully picking up a new GSR Steering wheel today - I've been looking for one for sooo long!
New heat shields. Look kinda average but I'm hoping they'll do the job for now! The bonnet has a heat shield so the theory is these two will guide the heat around the bonnet one and out the vent
Slowly making progress! The vibration is gone so I guess it was either the Tailshaft out of balance or the standard Unis or both. I put the Tailshaft back in and also installed two new adjustable shocks in the rear on their hardest setting. The back end still seems really creaky ( the slightest movement in the car causes weird noises back there ) but it drives more stable. The locker is so noisy though so it’s hard for diagnostics on the road. I gave it a quick road test and from standing start it tramps a couple of times then seems to hook up nicely. I was too scared to jump on the brake though which is where the trouble came at the drags when staging. I was only running 10psi so I wonder with the extra 5psi or so whether the rears will light up smoother? So now I’m at a cross road. I think the car is ready for a quarter mile run but only if I’m nice to it. I think if I’m savage in staging and off the line I’ll be in trouble. So whether I throw more time and money at the thing in the form of heavier Springs in the rear and replacing the remaining control arm bushes ( they all look ok at this point ) I’m not too sure…….
I'm bored so thought I'd update the thread. Can't believe it was October since my last post! Well alot has been happening since Oct 17..........ok that's a lie. Absolutely nothing has happened to the car! Getting booted to 5th in the Mitsi comp voting and missing out on the money I was going to use for a Heathcote trip kinda broke my motivation. The car in theory is pretty much ready but we have no track and funds are lacking. Hopefully something will change soon.....
