CtrMint

May be you can bob one on for me when you have the 620 in July

Hi All, I've finally booked myself on some club track days, albeit before the 620R is ready, but figured it will give me the focussed to push the remaining fixes forward, ie sorting the fueling. I'm now looking at the tow strap/hook requirements needed for the club track days. I'd be interested to see and hear how the track day regulars set up their solutions. I particularly want to ensure no damage occurs during towing, I suspect the nose cone could be vulnerable. Thanks

Just for balance, I always aim to put the very best quality oil available in regardless of cost, assuming correct grade. My logic being if you work out the cost difference over the life of your ownership relative to what you've paid for your 420R it's still a small difference. Given the oil is protecting the engine, the heart of the car, why potentially put a lesser oil in. You're only saving ~30 per change I appreciate there is no exact science behind this and you could argue the protection is the same between the different quality oils. Given the lack of real scientific data, I'll go with marketing spin and assume there's something in more costly oil. At worst case its the same as the cheaper oil.

Krisfl I hear your pain. This was a particular low point during my build. For hours I thought it impossible to fit, in the end I did manage it, though even now I'm not sure whether by luck. The approach that worked for me was to catch only 1 thread underneath on both sides while someone hold the bar, then move the top into place and secure gradually. From reading your post it does sound like you've got the bottom in so I'm not sure my advice is really that helpful. It took me an entire day to do mine.

Awesome James and thanks. I think a simple opto-coupler solution will work, isolating and dropping the signal down to 3v. I can then feed my microcontroller from the signal knowing I won't spike the input. Though I'm currently back in the weeds of our original venture, currently questioning some of our conclusions. I'm trying to make sense of that infamous missing flow control. I may have found a different high level protocol SAE J1939 (BAM) using classic can which explains the missing flow control. Though I'm might be completely wrong, I've got my head in the books again.

I'm trying to build with the equipment I have, sadly that doesn't include a scope. I'm also concerned about peaks and noise that might occur on the signal line. Your comment however re which engine made me think, (420R btw) Maybe there is a simpler solution which avoids the various ecus and engines.

Hi Jonathan, yes I've seen the thread and the manuals, but I want to get into the real detail, I guess of the black and white connection. My knowledge of the automotive side is pretty thin.

Morning All, I've finally picked up my data logging project I started with John and James, and hope to finish it this time. My new found interest is driven by the discovery of some suitable hardware on which to productionise the build, something that was previously an issue. If all goes to plan, the solution should cost around £30 in parts! Plus require zero setup! Before I tackle the logger, I'm going to do a dry run, using the same hardware on an easier project, well in theory! Replacing the ACES rpm shift monitor. Documentation on how the ACES system picks up RPM is thin on the ground, does anyone know where I might find how it works, and the operating spec. Thanks

I've got a digital camber gauge, I'll get the wife to sit in the car and see how much change there is. Given how true the car felt in a straight line I can't be that far off with toe.

The rear suspension is setup accounting for the weight from a driver. Though I have to say the 420 is for touring and moderately quick driving. So long as it handles I'm happy, and it does. I've never driven it and felt it struggling to handle and of course with the Penskes it's rides even better. If I want real fast blast on track or road, I'll use the 620.

Yes, when driving the steering wheel is bang on center, and they is no bias in the direction the 420R drives. I don't have any turn plates, so will need to get the nose cone off to easily check lock to lock. I didn't check the 420R with ballast. My understanding that's mainly for corner weighting.

First off thanks everyone for the input. The job took all day, and for once completed without a fault. The steering is now absolutely center and the car drives spot on, at least on the road. It's complete true without any bias whatsoever. I've taken onboard the feedback with respect to the track rod length and balance, but I'll aimed to have a nose at that during the warmer summer months, its still a little chilly out there. Can you confirm what I should do with respect to checking and adjusting the balance if there is an offset. thanks

Hi All, I'm going to be doing a string alignment today in the garage. Having faffed with the steering column in the autumn I think it's over by one spline, causing a very slight offset in the steering wheel. I figure its a good opportunity to get do my first alignment. The method seems simple, but could I possibly ask which way should I rotate the track rod to increase or decrease the toe. Probably obvious to seasoned pros, but thought it worth checking, only a minor adjustment is required so I don't want to move in the wrong direction. Thanks

I've given the entire situation a lot of thought, and I still don't see why I struggled to fit both of the new carriers. As mentioned the lower legs were closer in but nothing more, I think there was just over 4mm difference. The only impact I can see is that the threads are further away when passing the bolt through the chassis etc, thus the impact from any misalignment exaggerated. When I tried fitting the carriers I tried a couple of approaches. Top bolt in, then secure the bottom; or Secure the bottom two, then lift the diff up to the top bolt and secure the top bolt.When I used the second approach it became clear I was hitting my boot floor and just couldn't get the diff high enough to insert the top bolt. This issue just wasn't present with my old carrier. I actually ended up buying the second carrier at my own cost, all adding to the rather expensive bill. I do have faith in the person I spoke to at CC, he has been head and shoulders above most so I'm happy to take his comments at face value and trust his feedback. It was the chap that performed my 620R revisions. Unlike the person that comically packaged a 420R top radiator cooling hose in small box and damaged it through stress by bending it back on itself, and is now refusing to acknowledge the damage. But that's another story. Another 80 quid down the drain trying to improve faults.......

Geoff, It's not totally quiet. But it's a plated diff, mounted under your backside. However the noise, especially during low speed reversing and maneuvering sounds normal, in fact it's now no more noisy going backwards than forwards. On and off throttle there is a small knock, but nothing more than I would expect. Previously that was pretty bad as shown in the video I originally posted when I first built the car and was told TADT. When I first built my 420R I recall making the comparison to the LSD fitted in the many rally cars I've been a co-driver in, mostly Group N and E spec Evos and Imprezas. On a road section such diffs on a stripped rally car are pretty noisy, though they are consistent with just the knock as the driveline picks up torque etc or can be graunchy when tight turning etc. My original 420R diff never sounded like that, but I was assured like everyone else it was proximity etc. Driving the 420R now sounds as I'd expect.

are you suggesting I don't know what I'm doing? I purchased a new diff, but really struggled to get it spaced and mounted. I could get 2 out of the 3 mounts in. I didn't struggle with the new diff using my old carrier. I measured both carriers using a vernier gauge and found the positioning of the lower mounts were closer in on the new carrier. I also purchased a second carrier and found the measurements on that carrier to be identical to the carrier which came on the new diff. I also spent an entire day until the 420R trying to get the new carriers in, a total of approx 8 hours. I assure you it didn't fit. When I reverted to my original carrier, I had it on the diff, mounted and spaced in well under an hour.

My email exchange contained additional information which suggested the change was after the delivery of my kit (Oct 2018) and explained the difference in positioning of the lower legs, albeit by a few mm. Two revised carriers, one on the new diff and a secondary one both had the same dimensions suggesting a consistent revision.

Wrt to changes to the diff carrier/cage, email from CC.

I am left pondering the outcome, with a couple of questions unanswered, but that's not a bad thing, just part of the journey. My original diff was significantly noisier, even with a break away torque of over 40ft/lbs. Unsure as to why the rear feels significantly better when reversing. The diff carrier has been modified since 2018, yet I couldn't fit the new carrier for interference on the boot floor.Is it possible CC has changed the specification on the diff again? Given the successful road test, next thing I need to do is check the break away, see what that's reading.

Tim I see your point.

I hear you David. Mind, I still can't get my steering as good as the 620R factory build, but I'm going to pursue that until it's as good as perfect.

Interesting you say, fixed. I never really considered mine as a failure, and certainly the advice from CC and their dealer network suggests TADT, and that mine was fine. While the diff had slightly increased in noise after the 500miles we did this year in the UK (Taffia) there was no evidence it had actually failed. My project was more preventative and also convenience, providing a spare facilitating a leisurely rebuild of the original. I also wanted to gain a better understanding of the diffs behaviour and potential rebuild process. Based on my sample set, which I appreciate is only 2, there's certainly a notable variance between the two I've been supplied.

One other observation. When I used to reverse the 420R, along with the awful noises, I used have this odd and very slight sense the diff was oval in action, or the suspension would lift, which it didn't. Daft I know. The same feeling didn't exist driving forwards. I'd previously checked everything was tight multiple times etc, but never found an explanation. Anyhow, I did multiple tests today in reverse (neighbours must had thought I was mad) and that sensation is gone. Better diff? or have I corrected a build issue from my original work....

I finally managed to test drive my 420R with the new Titan LSD today. I have to say, there's a big improvement. Of course there's still noise from the diff given where and how it's mounted. However, the awful knocks, clonks and low speed maneuvering sounds are pretty much gone. It's significantly better, basically completely reasonable given the Seven's construction, so much so I wouldn't feel any need to provide feedback to CC, and also don't feel embarrassed if pedestrians hear the Seven being maneuvered. I reversed full lock numerous times, a process which used to make the car sound like a bag of bolts, even with +40 ft/lb break away etc. The on/off load clonk is pretty much non-existent, yes its there, but significantly better compared to the original out of the box. What is really interesting, this diff is quieter than the original I received and drove from the outset. My first diff was never this quiet. The response, they all do that, is for me to some degree questionable. Yes they do, but if the volume on my original was 9/10 from the start, the new one is say a 3/10. So there's clearly a sliding scale here. My testing today also contained more extreme use than the 420R has ever seen, certainly with respect to the diff. I took the 420R out on ZZR tyres in wet/damp conditions. I was able to light the rears up in 1st and 2nd gear, the rear felt great, completely consistent in terms of movement at the rear when the tyres were expectedly overwhelmed with my throttle input. Huge fun too. As a recap, I dismantled the rear, and rebuilt everything from the prop back. All new hardware, nuts, bolts, washers etc. Diff shimming was slightly different, I used more of the super thin ones. I added additional (externally sourced) super thin shims between the A frame to improve the balance, CC supplied hardware resulted in a slight offset. I reused the original diff carrier, two new carriers just wouldn't fit, no idea why! Fitted a new handbrake cable. Used the Motul diff oil. I didn't fit the gearbox spacer, after speaking with CC they advised its use where contact between the gearbox and chassis occurs. They suggested there was no evidence it improved the diff noise. I have purchased the spacer, so might fit out of curiosity.I also changed the gearbox to Redline MTL, while difficult to say for sure, I do think its improved the shift. I suspect people are going to suggest that it won't last, and I get that. I'll need to check the preload next, and see where it's at.

Hi, I've just been to book a track day (@Oulton.. great !! ) via Love Admin and noticed you require a UK or EU driving license. Technically I hold neither, although I originally passed my license in the UK, I've surrendered that years ago for an Isle of Man license. Could you please clarify how I should reflect my license. Thanks