Sirion AWD conversion/ autocross build

Now I have about 35mm from ride height to full droop on the rear. When I had a test drive the other day it felt like it was lifting the rear wheel when cornering, but I couldn’t say for sure. I think the original front springs are stiffer than the eibachs, I didnt take any measurements but they seemed to have one less coil than the eibachs, I will have to measure the wire dia. and work out what they are. I will do some more test driving this afternoon :grin:

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35mm would be a great start. Does depend on how much bump there is in the front as you’d not want to only just start lifting a wheel as the front hits the bump stops.

Watch out rival competitors Daihatsu coming through!

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Here are some photos of the power steering cooler. Its from a VW phateon or something, it was the cheapest thing I could find on ebay. Its probably overkill, but since it is fitted to the low pressure side the cooling efficiency wont be as good, but I think it should work well. At some point ill fold up a sheet metal duct for it to help feed air through it and protect it from stones ect.

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Here are the results from yesterday. Please understand its only my 3rd time driving slalom, my first official race, and I am driving in the highest class against cars that are probably worth more than I make in a year.
1terNACGLPneu.pdf (138.5 KB)
24terNAC3a.pdf (131.7 KB)
23terNAC3a.pdf (132.4 KB)

I still have a way to go to be competitive in this class, I am the only one running semi slicks and my suspension still needs more work. But I finished 3rd in class for the GLP which was great!
The car sticks to the road better than before, the biggest problem now being the high centre of gravity, I found myself up on 2 wheels many times :sweat_smile: I also found myself lifting off the accelerator alot as a result. I have a month until the next race, I will take a similar route as @Mr_Gormsby with the rear springs to get the rear lower, and the eibachs will be going back in the front end.

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I also had the pleasure of diving the Polo for a few laps, the thing is crazy! There is no power under 4k and limiter is at 8500, the final drive is so short you have to do half of the course in 3rd (I dont even get out of 2nd in the sirion) and the slicks and suspension was a whole other world!

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Made some really nice headers yesterday :slight_smile:
Started with an exhaust manifold from a Mercedes A class I picked up off ebay for 30 bucks

s-l400%20(1)

Some small modifications to get everything to line up with the K3 flange

And the finished product :grin:

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Nice work man. Looks like it was made for it.
Your doing some nice and genuine functional enhancements there. I like reading your updates.
Keep it up.

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Hi guys, its been a while since my last post, ive still been doing a bit to the car and thought I should share an update.
First up here is a video from the race back in April:

Since then I have built the headers shown above and also built an exhaust using mandrel bends, I stepped it up to 45mm to match the REMUS exhaust on the rear of the car.

I also went to town with poly bushes, im now sporting the entire Siberian Bushes catalogue, ive fitted a second set of swaybar bushes and ive done a bit of work to the rear to lower the car and fitted a pair of fiat Abarth lowering springs with a slightly higher rate than the oem Abarth springs I was running before. When I get around to it ill post some more photos and a video from the race in may, and the next race is one week from now. For the time being ill stick to the current setup and focus on tuning the handling through tyre pressures, as alot can be done in this regard.

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I was wondering if that oversteer might have been some rear steer. The 2wd get some toe out under brakes and cornering due to the beam. The 4wd though might have the rear axle moving to steer a bit due to soft bushes, but only a guess.

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Here are some more videos.

the afternoon run from April:

The race from May which was somewhat of a disaster:


Unfortunately i dont have any footage of the afternoon run from back in May, all i can say is it was a little better but still not great.

And here is the last race from last week, it was excellent, managed to pick up my first trophys for the season.

Now we are halfway through the season and there will be a break until August, im currently ranked 3rd in class for the NWD Cup!
NWD-Cup 2018.pdf3a (4).pdf (30.8 KB)

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Very good - well done. Have had a busy couple of weeks with work. Am on school holidays now and should get your TB done soon. Had to go up one size in thread for the plate screws. Consequently both sides of the axle are threaded. I forgot to mark the orientation. I’m 90% certain which side to drill and counter sink but want to double check.

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No problem, let me know if you want some photos of the origional for reference. I have also been thinking about what you said earlier about the rear steer, it could be the case! I have a plan to convert the rear end from panhard bar to a watts link, but it will be a while before i get to that. I need another donor car to pinch the panhard mount from, then weld it on the left side, then it would be pretty straight forward to make up a simple watts link. It would be ideal to find a 1.0 litre awd as a parts car, then i could swap the gearbox and diff at the same time for some shorter legs… a plan for winter i think. I have also sent off my spare flywheel to be lightened, a brother from a work collegue has taken on that job, hopefully it works out well. I also bought one of those crank sensor wheels i told you about that has been advanced 5 degrees, so the plan is during the small break ill drop the motor again and throw in the flywheel with a new clutch and the sensor wheel.

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Panhard can work but needs to be really long and suspension travel really short. Watts would be less compromise from a functional point of view.

Might need some pics. Sorry, I’d normally make a mark, The offset tab that goes into the throttle position is offset. Where does that sit at the closed position?

@Mr_Gormsby at the closed position the tab is vertical, at WOT when the butterfly is vertical the tab is tapered ever so slightly downwards towards the bottom rear (rear is the coolant channels). Here are some photos, but im not sure if they will help because its hard to see the angles properly.

The first and third photos are closed position and the photo in the middle is at wot

They help. I needed to see which way the offset sat.

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I got my flywheel finished, but I may have a problem… When I told him how much material to remove I didnt think to measure how deep the threaded holes were for the back piece. Here are some pics.

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Holes need not be deeper than one and a half bolt diameters

I mean the holes closer to the centre that hold of the backing plate on, the clutch disk will be riding over them. The holes for the pressure plate are ok.

@Mr_Gormsby do you think it will be ok?