The Civic 25XT

[ChargeR]

Wow what a cool little car! I can imagine it would be fun around the track.

Thanks! Very slow on the straights, but it suits me just fine.

I acquired a pair of SSR MKIII from a gentleman in Sydney today. They're pretty rough like my MKIIs but I'm thinking of putting a tyre on one to use as a spare in case of flat tyre I can still roll in (mismatched) style. Specs are the same as my current rear MKIIs, 14x6.5 +19.

[felixR]

You and your wheel finds!

[eskimo_firefighter]

Your post on the bump steer is pretty awesome. Always learn something new from your build threads from your DC5 one to this one.

I guess with fixing the bump steer issue would improve its cornering abilities as its under less stress due to less toe changes while also allowing the tyres to last a bit longer? Just trying to learn that's all as this stuff is quite interesting to me.

With the modifying of the tie rod pick up point does that actually involve exactly if you don't mind me asking? I'd like to also see if you ever get the chance what your take is on fixing the bump steer issue on the DC5.

[ChargeR]

You and your wheel finds!

I can't help it I just love wheels.

Your post on the bump steer is pretty awesome. Always learn something new from your build threads from your DC5 one to this one.

I guess with fixing the bump steer issue would improve its cornering abilities as its under less stress due to less toe changes while also allowing the tyres to last a bit longer? Just trying to learn that's all as this stuff is quite interesting to me.

With the modifying of the tie rod pick up point does that actually involve exactly if you don't mind me asking? I'd like to also see if you ever get the chance what your take is on fixing the bump steer issue on the DC5.

Thanks guy, appreciate your comments. The biggest difference I think in my particular situation would be improved response on turn in, as it is now it's like having a lot of static toe in at the front since once the car dives under brakes it's well into the bottom part of the curve (on the graph above). Good for stability but not great if you want to turn into a corner, and it's only going to get worse once I lower the car more. Tweaking the bump steer won't change the amount of cornering grip the car will generate but it should make the car easier to drive and more responsive, particularly in the transient parts of the corner like at turn in.

I'm learning here too, when I first make the changes I'll aim to set it up so the toe change is like it would be at +40mm of ride height on the graph above. Slight toe out tending to none in bump. I'll see how that goes to start with.

Modifying the pick up point simply means that I'll be changing to an alternative tie rod end design so I can alter the height of the outer pivot with spacers to correct the bump steer. Something like THIS but better.

In the future this will be useful to correct the bump steer after geometry changes on the CR-X, and I'd consider it essential with parts like roll centre adjusters fitted. Regarding the DC5 issue, here's a post that I prepared earlier: LINK Similar deal though, since you can't easily relocate the steering arm on the strut or the location of the steering rack the best solution is to move the inner and outer ends of the tie rod up/down to get the best bump steer possible given the limitations of the suspension layout.

[ChargeR]

Spent a bit of time today preparing the bits of my DIY extended top mounts so that I can stick them together with metal tomorrow, I'm using a bit of 50mm exhaust tubing kindly donated to me by the exhaust shop around the corner. Still undecided how much extra height to add, there isn't much room available before the adjusters on the Koni dampers will interfere with the bonnet, I'll probably err on the high side and then I can space the damper shaft down slightly with washers if required

Probably won't make them this tall:

[hello]

been a while since i read interesting stuff in a build
thanks charger

[ChargeR]

been a while since i read interesting stuff in a build
thanks charger

Thanks mate, glad someone is reading my ramblings. Don't worry, updates on the CR-X are coming .

Today I started putting together my DIY extended upper shock mounts. I decided to go with 35mm extensions and as mentioned above I will add washers if required beneath the upper shock mount bush to get the top of the shock shaft sitting where I want (ie. not hitting the bonnet). Accounting for the material removed in cutting up the stock mounts these should end up around 29mm higher.

The aim is to gain more bump travel, as with the standard length Koni and top mount the shock will bottom out before any other component interferes, and it only gets worse with a bump stop fitted. After fitting these mounts contact between the upper control arm and the body should be what limits my bump travel, so I'll set up the bump stops to just prevent that contact giving me the maximum travel available.

Here's the bits all ready for welding:



And here's them partially welded together after I ran out of gas. I ended up using some 0.9mm mild steel MIG wire that I found lying around for filler, because I left all my other stuff with the CR-X, but it seemed to work okay.





Also here's a brief video from when I last went to Winton. I didn't record my PB lap unfortunately, the video is a 1:49 something. Looking at the video there's still a lot of work to do on my driving, particularly bad are the points where I pull the steering wheel into the corner with my inside hand and I'm still much too abrupt on turn in at some points, a legacy of the Micra I think. Apologies for the poor quality of the video, and the audio.

[eskimo_firefighter]

Nice driving and update. No braking and flat foot on the accelerator entering the sweeper? That's scary even in an underpowered car. .

[munkaii]

I think you're pretty spot on with using the inner hand to initiate that initial steering input. I have the same issue at times but for me it's more a case of using that quick input to feel for that corner entry grip.

It's amazing though that the laptimes are in the 48/9s. Definitely shows where you make time compared to other high powered cars.

[ChargeR]

Nice driving and update. No braking and flat foot on the accelerator entering the sweeper? That's scary even in an underpowered car. .

Thanks fellow, yes I'm flat into the sweeper until about 1/3 of the way round. It's really not scary at all, the car has so little power and quite a lot of grip even if it gets out of shape it's easy to bring it back into line .

I think you're pretty spot on with using the inner hand to initiate that initial steering input. I have the same issue at times but for me it's more a case of using that quick input to feel for that corner entry grip.

It's amazing though that the laptimes are in the 48/9s. Definitely shows where you make time compared to other high powered cars.

Thanks for the comments, later in the day I did make an effort to keep my hands at approx. 9 and 3 and initiate turn in with my outer hand along with being more smooth and I think it contributed to the PB but I'll have to make the effort to get all my sessions on video next time so I can compare more easily.

[ChargeR]

The weekend before last I headed up to Winton for the Circuit Club event. The day was clear and cold, perfect weather for PBs. The only change since the last event was the addition of the eBay header, and oil change with some Red Line 10W-30 instead of 10W-40, and flushed out the brake fluid with some ATE Super Blue.

Here's a few photos from the event:

Thanks to A-Wong Photography:



These couple thanks to CelicaJim from EXE:





Lap times from the event:

Session 1
2:06.5120
1:52.8580
2:00.0830
1:48.7650
1:49.2060
1:50.7700
2:03.4870

Session 2
1:53.7440
1:49.0870
1:50.8760
1:49.9150
1:48.5610
1:49.2680


Session 3
1:57.7800
1:52.1060
1:50.9220
1:48.9880
1:48.7610
1:54.1820

Session 3
1:58.1880
1:49.4040
1:49.1350
1:48.9080
1:52.0780
1:49.9110

Overall it was a great day, thanks to the CC guys for coming down and putting it on. All of the drivers in my group were courteous and I had plenty of room on the track despite a greater number of cars on track than previous days I'd attended. The higher number of cars meant I would have got more laps in than a typical day had I not headed off early, and missed a session.

My PB for the day was a 1:48.56, a couple of tenths quicker than previously. Also my optimal time on racechrono has dropped to a 1:47.5 so there is certainly more in it. Here's a speed comparison between the times at this event and Tampered last month.



And this is the full lap speed trace, click for full size.



Comparing the speed traces it's obvious that I've picked up good power from the eBay header. Even with worse mid-corner speed and exits speed is up noticeably at the end of all the straights. Apart from that there's not a lot of difference from last time, once I get back to where I was previously mid corner and at corner exits I should be able to drop into the 47s.

During the day I started to experience a small hesitation or misfire on the exits of a couple of the corners, particularly following the sweeper. I suspected that this was due to oil finding its way into the distributor and causing a misfire, so I pulled off the distributor and took a look inside:



Definitely not ideal. I've picked up an oil seal for the shaft from CBC, and I'll be ordering the O-ring that seals the distributor to the head along with some other bits to give it a bit of a refurb. I also had my DIY top mounts sandblasted and powdercoated (thanks to itsu-san), I'll fit them up soon:

[tinkerbell]

good work on the PB mate

[Oz Striker]

Nice work Tom! You weren't far off your PB on your 4th lap of the day! Lol it's funny how that happens sometimes

[ChargeR]

Nice work Tom! You weren't far off your PB on your 4th lap of the day! Lol it's funny how that happens sometimes

good work on the PB mate

Cheers gentlemen. Yeah Ryan, there's no doubt my driving didn't get any better as the day wore on, and I have a lot of trouble managing tyre temperatures. I'm not sure if it's me or the car setup but it seems like no matter how hard I try to be smooth and limit the slip angle of the tyres the fronts seem to get too hot and get greasy.

[Oz Striker]

Cheers gentlemen. Yeah Ryan, there's no doubt my driving didn't get any better as the day wore on, and I have a lot of trouble managing tyre temperatures. I'm not sure if it's me or the car setup but it seems like no matter how hard I try to be smooth and limit the slip angle of the tyres the fronts seem to get too hot and get greasy.

The joys of the fwd and street tyres lol I always found the same thing, once your street tyres go through the first bit of abuse in the first session, they don't seem to come back as well for the rest of the day. Plus you get tired and go through the motions a bit. It's still a decent time though considering!