baby_Carlton

The reason for replacing them is not for quality, its for fitment. I'm pretty sure Viking offers a coilover long enough to fit with my SLA design but I know the Penske one will work. I just need to check for interference in the UCA throughout travel. Lol well if you wanna save a few pennies on the front kit from AE let me know, I'm going to get rid of mine. That last part is probably true, but more tie rod ends means more maintenance and more failure modes. Dirt and debris entering the ball joint and load fatigue both contribute to this. I've spoke to Viking and they were very helpful. A little confused on the choice to use the C203 shock with the motion ratios given to me by Apex. From their reaction and the assessments from Rob Fuller and Mike Maier I'm standing by my opinion that 3.2" of shock travel is simply not enough.

I see, it seems AE just sent me 4 identical C203 shocks from Viking and said have at it. I won't be using them anyway, the entire front suspension kit is pretty much a wash for me at this point. Going to just resell it for cheap once I finish my own design. I'll be either using JRi modular shocks that are 21.7" extended or Penske 24.7" extended. I agree, there's too much usage of many tie rod ends, from an engineering perspective it just adds more and more failure modes, more and more maintenance. I'll edit this post and link my front SLA thread.

I just received the kit on Friday, the front kit will likely stay uninstalled. Not sure what you mean by "asking hypothetically", I'm designing a new front SLA suspension that will allow a full length coilover to mount to the LCA.

I'll take the scan if you still got it, appreciate you doing this. I have a scanner at work but its difficult to justify bringing home a $50k+ piece of equipment for the weekend XD

I agree, I reached out to Apex earlier this week asking about feasibility using the existing shock stroke with 400-450# springs. Yes, loading the outside tire on burm and then hitting an imperfection on the track seems like it would decimate one of these shocks (same with hitting kerbs/rumble strips) unless I find a way to get more travel. If I could get 5inches of travel I would be very happy but I will try for a full length (~6.5") shock design if I end up copying MMI's Mod 2. Very interesting, would definitely prefer welded to bolt-on but if everything fits up right I could end up using it as a way to test different upper wishbone lengths. The Griggs conversion looks like a pretty strong structure but I don't want to jump to conclusions quite yet. Do you have any photos of your work? Interested to see what your mounting solution looks like. If I can avoid trimming the strut tower and still get the full stroke shock I will.

Tire selection is Nankang CRS 200TW 245/40R17 front, 275/35R17 rear, I would use their AR-1 100TW however they do not offer a 275 section tire for that model. Car will be almost exclusively a track car but despite my spine's best interests it'll probably see a very occasional Sunday drive. Were these rates with OEM-style strut type suspension? What were your wheel rates? Maier's issue with the shock travel was that unlike an autoX/hillclimb car, a road course car would see burms and 3.5" total shock stroke just isn't enough. Great insight still, thank you. The kit just shipped about 3 hours ago (for better or for worse), when it arrives I'll be able to get those measurements to see. When you say "adequate travel" I'm assuming a that refers to just enough travel for the ~3 inches of travel you've needed for your own car? I'm assuming if I want something closer to 5-6" travel, the upper arms would need to be closer to a foot long. That's what I'm finding as well just looking at Maier's Mod 2 front axle suspension kit. Complete replacement of the front strut towers moving the pickup points slightly upward and a few inches inward to increase clearance between the coilover and upper control arm. I'm not opposed to doing this and I could even keep most of the Apex kit except for probably both the wishbones. Ah yes, old stockcar components on eBay, a true goldmine for (hopefully) decent parts. Definitely have looked at sourcing a fuel cell and oil coolers from there. Luckily I have access to rapid prototyping equipment and fabrication tools so I'm good to go. Not the best welder or anything but I know a few. Thanks for your help tube80z. Only other gripe I have with this design is on the rear subframe; the differential and control arms mount on the same structure and that seems like an exceptionally suboptimal design choice. Time will tell I suppose.

Spoke to Mike Maier today seeing as the front suspension is most similar to that of an old Mustang. I wish I could write notes faster because holy hell that man is a wealth of knowledge. Suggested the reason for high spring rates is to prevent the upper control arm from camming over (poor arm design) and that the 3.5" of travel is definitely not enough for a road racing/track car (burms). Looks like my next steps are installing an adjustable upper ball joint that can move up/down to change the coilover angle and shock pot it at ride height looking for the lowest load value. If no substantial gains can be made there it's either back to the drawing board to make a push/pull rod cantilever or cut out the shock towers entirely and try to copy MMI's own Mod 2 strut tower modifications as well as new control arm(s) to gain the ability to mount a full length shock to the lower wishbone. This is becoming more and more of a fully custom project by the day.

Update From Apex: Front • Motion ratio: 0.92 : 1 (wheel : shock) • Wheel rate: 0.92² × 600 lb/in ≈ 510 lb/in • Wheel travel with 3.5" shock stroke: ≈ 3.2" Rear • Rocker motion ratio: 1.00 : 1 • Wheel rate: 700 lb/in • Wheel travel with 3.5" shock stroke: 3.5" Some confusing design and hardware choices here. Using a bellcrank/rocker with a 1:1 motion ratio doesn't take full advantage of the system. I will end up designing and having manufactured a new billet bellcrank/rocker with a lower motion ratio to get more shock travel. Highly likely I'll source a Hyperco spring at a different rate but that'll be handled during the bellcrank redesign and is a straight forward task. The front axle is giving me some headaches. The lack of suspension travel could be fixed by adding a bellcrank/rocker, but there isn’t enough space to fit one between the top of the strut tower and the hood. Making room would require major cutting and fabrication to the strut towers. Mike Maier Inc.'s solution to a similar problem was to completely replace the original shock towers with a custom design, allowing a full-length shock to mount higher and further inboard. On the Z, moving the strut tower further inboard could create enough clearance between the upper control arm to let a coilover mount to the lower control arm. But by that point, I'm only a few steps away from designing a fully bespoke 1:1 double wishbone kit, making the OTS kit a useless purchase. I've been drawing up some concept sketches on how I could possibly do a pull rod but that would render the OEM strut tower essentially useless. Alternative to implementing a front axle rocker would be to modify the upper wishbone where the bottom of the coilover mounts to be further inboard which would lower the motion ratio more but I'm not keen on trying that solution. I think I need a sanity check, I'm used to working on strut-type suspensions that have decently high shock travel to the point where coil-bind is a more pressing issue at low ride heights. Is there another solution to a short shock stroke and high spring rate I'm not considering? Or is this a case where the problem is all in my head and having 3-3.5" of shock stroke isn't that big of a deal? I've spoken to Rob Fuller from ZCarGarage regarding this problem who had some great insights on Z suspension, unfortunately he wasn't able to help me much past confirming that the wheel rates are ludicrously high. I'm aiming for a front axle wheel rate in the range of 300# to 450# and even then 450# still seems extremely high for the front axle.

Thanks for the welcome back, this car has certainly had a rollercoaster of a fate over the last 10 or so years of ownership. Excited to build it into the best version of itself (for me). Thanks for the info, seems like Viking is a non-hype brand that offers shocks that do shock things, which I can appreciate. AE is slow on CS communications but that's understandable given the size of their operation. That said, for a ~$9K suspension kit, a bit more transparency and technical detail on their website would go a long way. If I can find a shock with more travel for the same dimensions or when I blow these out I'll swap. JRi's builder series and some of their GM line looks like it would bolt right in, only 0.3" longer extended length which seems negligible in terms of fitment (PN: 100-511-300). I agree, it seems incredibly unwise if that were the case but it wouldn't be the first time I'd seen it. I've seen similar suspension choices in GTAC (cars riding on bump stops) but that's usually done purposefully to keep the aero platform working optimally and not appropriate for a package like this. Considering the shock travel is a mere 3.6", its safe to assume this is an extremely low motion ratio design. It feels like a missed opportunity to fully leverage the bell crank inboard design (traditionally speaking) but perhaps packaging constraints of the S30 chassis left little room for alternatives. I'm hoping the bottoming out feature will be at the upper A-arm which would allow me to mount a 3D printed polyurethane bump stop on top of it. Going to email AE for an update on the wheel rates and now information motion ratios, thanks for the idea.

Hi HybridZ, its been a while. Took a long sabbatical from working on my S30 to finish college and get a job. For the last 6 or so months its been full steam ahead, the project is currently being rust repaired at a local body shop and I've been collecting parts as budget allows. The first piece major piece of hardware to arrived is the Viking Performance Shocks from the Apex Engineered Track Attack Front/Rear Suspension kit. I noticed that Apex’s website lacks details on shock and spring selection, so I’m documenting my findings here for others and to start a discussion on their choices. What's Included: Box as it arrives from Viking Performance Serial Numbers of each of the shocks (PN: C203) Viking Performance Shocks Link Part Numbers of Springs (600# & 700#) Initial Impressions: The car will be caged and used primarily/almost exclusively on track, so a stiffer setup is expected. However the spring rate selection still raises some concerns: The S30 chassis doesn’t benefit significantly from extremely high spring rates, even with a roll cage. The rear suspension uses inboard cantilevered shocks, which traditionally increase effective spring rate via the lever arm. This spring selection guide from Viking Performance indicates that the spring rate for a car with IRS and axle weights of ~1200-1400# is a lot lower than the supplied springs. I'm hypothesizing that the high rates were chosen to prevent the shocks, which are short to fit the Z’s narrow frame and tight packaging within the front wheel wells, from bottoming out. I’ve reached out to Apex Engineered to clarify the wheel rates for this setup and will update this thread when I hear back. Let me know if any of you have run this kit or high wheel rates.

My friend bought this car! We painted it.

Just wanted to update for anyone having this issue in the future. Culprit was the front cover seal being all wonky. When I installed the front cover I didn't take the time I should've and I wasn't making sure the gasket was seating while the front cover was being tapped on. The front cover bolts dug into and thru the gasket. This meant the suction side of oil pump was not sealed against the front cover and a vacuum could not be made. Cam oils, car runs, all is well. Thanks to everyone for the suggestions and help!

Haven’t messed with anything in the oil pan and it was working before the rebuild so not sure what could be blocking the tube. I think I’ll have to eventually take the oil pan off and inspect. Thanks for the help!

Gauge wouldn’t be a bad idea, I’ve removed the oil filter and turned the pump (CCW), no oil shoots out despite having 5 qts. Does the oil pump AND distributor seal some oil galley I’m not seeing? I think the only seals I need to be mindful of are the front cover to engine block/oil pan.

Hi all, I recently built my P79 head (F54 block) and have reassembled the engine and I’m having a problem with the oiling system. The conditions are as follows: -Oil pump confirmed will pull oil in and push oil out (primed and greased) -Car will start and run but internally oiled cam will not spurt out oil -All 5qts of oil has sunk down into the pan. Tested oil passage with compressed air going out from the oil pump and into the oil pump. Output side is working as it should. Input side is not blowing thru. I’m using a rod attached to a 12V drill to turn the oil pump thru the distributor hole in an attempt to pull oil out of the pan but so far no dice. My theory is that the front cover of the engine is not sealed at the oil inlet from the pan and won’t create a vacuum for the oil pump. I’m curious if any of you have experienced this, I haven’t been able to find answers to my issue. Thank you