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#1
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Rear shock travel
With the new Moser rear end and drop springs in my car, I'm wondering of the Bilsteins don't have enough travel as I'm hearing thunks and feeling harshness over larger bumps.
On the ground, it's a little over 15" from the bottom of the shock mount to the top mount on the frame. The compressed length of the shock is 13.11. Compressed, the shocks appear to have around 2 to 2-1/2" of available travel. What's considered sufficient travel to for rear shocks?
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Ken '68 GTO - 464 - Ram Air II heads - 236/242 roller - 9.5” TSP converter - Moser 3.55 Truetrac (build thread | walk around) '95 Comp T/A #6 M6 - bone stock (pics) |
#2
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Travel in general is roughly 30-45% of travel in the center of the travel range. But that's a 'general' rule of thumb. You can use 50% for easier calculations, but that's outside of the general 'effective' range of the shock.
A better question would be, what's the compressed measurement of the shock? Other questions: What's the range of travel of the new drop springs? Are they a progressive spring? Do you know the rate? Since drop springs are generally shorter, they tend to have a higher rate. Bilstein's are a 'baseline' standard for a shock IMO, but in my experience, they are a little harsh and tend to wear out pretty quickly in my apps, which are a lowered stance over OE. Hammering the shock at either end of the travel range beats them up. And A-body 4-link setups are travel limited by the shock by design. You have to remove the shock to remove the spring. .
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. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
#3
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There are shock extensions for the shaft, look at truck accessories to find them.
(EDIT Be careful not to go too long, if the shock overextends, the spring can pop out. Don't use poly shock bushings either. The hard rubber ones are best. An adjustable shock is the way to go, but, obviously, there's a considerable cost increase. .
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. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
#4
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The springs are UMI 2" drop springs. According to their site, they're linear with 130 lb/in - same as the 1" and stock height springs they offer. I don't know the range of travel.
I've had these Bilsteins for about 10 years. There's not a lot of compression or rebound, and they feel like they got more stiff once I lowered it some more. I think I want something that's a little more forgiving. I've been looking at QA1 or Viking adjustable replacements. Kind of wishing I bit the bullet and went with coil overs when I did the rear end.
__________________
Ken '68 GTO - 464 - Ram Air II heads - 236/242 roller - 9.5” TSP converter - Moser 3.55 Truetrac (build thread | walk around) '95 Comp T/A #6 M6 - bone stock (pics) |
#5
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Well. Depending on your front LCAs, keep in mind not all brands allow for the double adjustables. I found out the hard way with QA1s and Speedtech LCAs.
I ended up with RideTech single adjustables in the front, and honestly, I wish I had got them for the back, too. I have QA1s on the rear of mine, with GW springs, they are about 1-1.5" lower. The QA1s work great, and if you go soft on compression, it squats and hooks really good. When I drive kind of day-to-day, I crank up the compression by 5 turns and leave the rebound alone. On the front, I have the Ridetechs cranked all the way up. With the added weight of the endura nose, the serpentine setup, and a few other things up front, it sits a little lower than I like, and it bottoms more than I like. And I'm at like 680#-700# springs now. I think if I went up a step on the springs, I could probably have more tune in the front shocks. I do wish I would have known about the QA1s not fitting in the front LCAs, I would have gotten Ridetechs for the rear too. Because of the way you 'should' dial the shocks, it's like every 2-4 turns on the compression, you're supposed to go double on the rebound. So in a way, double adjustables are really only for track/autocross. With all that said, 10 years on any shock is way past time for replacement. Most recommend replacement every 4-5 years, but you could probably add a couple if it's not driven as much. But gas charged shocks, even if they are just sitting there wear out over time. Shocks like Viking, QA1, and Ridetech are rebuildable, so it is kind of a long-run thing (to get return of investment). QA1 purchased Speedtech & Viking shocks, so they are probably going to merge those two lines. All three will spec shocks on length by the way, but you have to be careful when you start messing with length. I have a brand new setup of double-adjustable QA1 front shocks that I am going to sell, But one has to be aware of the fitment limitations. I'm going to be clear on that once I list them. I'm not a fan of the coilover 'conversions', there are inherent issues with some of the spring setups, and it take a number of shots to get the springs right. One thing, progressive springs are a big no-no, which most coilover conversions use. . .
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. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
#6
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I hadn't considered RideTech. It looks like the rears mount with the rod on the bottom which is different from most other brands. That would actually solve another issue I have with the Bilsteins and how tight they fit by the bottom mount.
__________________
Ken '68 GTO - 464 - Ram Air II heads - 236/242 roller - 9.5” TSP converter - Moser 3.55 Truetrac (build thread | walk around) '95 Comp T/A #6 M6 - bone stock (pics) |
#7
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Yeah I didn't realize that. The Bilstein's shaft protectors on mine always contacted the exhaust where it goes over the rear tube, always melted on mine.
I went back & forth with Speedtech over the QA1s not fitting, and they kept telling me to mount it from the top? I was like, how can you possibly compress the spring with the shock in the way? They just couldn't understand, or at least the guy I was talking to didn't. I sent him a number of pics, and then finally, he agreed, it can't be installed the way he was telling me to install them. And once he reach that conclusion, his response was 'Well, they are originally designed for a coilover setup, coil spring use is secondary'. And I showed him right on their' website, the listing states 'can be used with factory parts'. And then they went dark on me. Unbelievable. The QA1s do work with the OE LCAs. Another thing, even if I could get it mounted in there, the coil spring 'pad' would prevent any adjustments while installed. And you would still have to hog out the pad to allow the adjusters up in there. The GW arms have a larger hole, and the pad is larger around too, so the QA1s work with them. And they have nuts welded on the inside of the arm so the shock bolts can go in from the bottom. QA1s come with a bolt and nut. I even went as far as using rivnuts in the arms so I could run a bolt up from the bottom. There's just no way they will work with the QA1s. Maybe QA1 will fix the design of the lower arms, so people in the future will not get stuck like I did. To top it all off, the arms dropped my ride height by 1-1.5" too. Was not happy at all with them, will never buy them again or recommend them to anyone. .
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. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
#8
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I could hog that plate out enough and use a GW coil pad, and it would 'work', but that's an added expensive & effort. They should just work, plain and simple.
The plate and rest of arm is strong enough to deal with the coil spring, but then there's the whole 1-1.5" drop too. It's just a fail/fail IMO. .
__________________
. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
#9
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Yeah, the protectors on my Bilsteins ride on the exhaust with the new rear. I don't like that.
I have stock control arms on the front and am pretty happy with the way the front of the car handles. The back end got better with the GW control arms, but now the shocks feel pretty unforgiving. A set of new single adjustables would probably be sufficient. I just want it to handle nice under regular driving conditions. I don't see myself ever autocrossing the car, but the drag strip is a possibility.
__________________
Ken '68 GTO - 464 - Ram Air II heads - 236/242 roller - 9.5” TSP converter - Moser 3.55 Truetrac (build thread | walk around) '95 Comp T/A #6 M6 - bone stock (pics) |
#10
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Wouldn't you know it, Jegs is having a Labor Day sale. As a result, I have a set of Ridetechs shocks on the way to replace the Bilsteins.
__________________
Ken '68 GTO - 464 - Ram Air II heads - 236/242 roller - 9.5” TSP converter - Moser 3.55 Truetrac (build thread | walk around) '95 Comp T/A #6 M6 - bone stock (pics) |
#11
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Very nice! You will love them!
Interested in your feedback on those, post after you have some drive time. .
__________________
. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
#12
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I've had the RideTech shocks installed for about a week and a half now. The cylinder on the rear shocks is smaller than the Bilsteins, and they mount with the shafts on the bottom, so they solve the issue with tight clearance I had with the Bilsteins. On the fronts, I had to open up the bottom of the control arms a smidge to get the shocks installed. Not a huge deal, just kind of annoying.
So far, they're a huge improvement over the Bilsteins. They have a much more thoughtful and forgiving ride on the street setting. Pricey for a set, but by far the best shocks I've had on the car.
__________________
Ken '68 GTO - 464 - Ram Air II heads - 236/242 roller - 9.5” TSP converter - Moser 3.55 Truetrac (build thread | walk around) '95 Comp T/A #6 M6 - bone stock (pics) |
#13
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They are great shocks, and I also had not considered them before until someone commented on them. So I dug a little, found they are reputable, and well received by many, and pulled the trigger.
I was just going through looking for some other stuff in my notes and found some spaced out lower shock mounts I had previously order, so pretty sure I too had that clearance issue you were talking about. Here's the link to what I got: https://www.speedwaymotors.com/Speed...Bolt,5485.html I think I have those on the 442, or I accidentally left them on the diff I just sold when I swapped my Moser. I squealed and moaned but pulled the trigger on a new set of GW LCAs, so I will be going to the QA1 doubles I already bought up front. But I will get some matching Ridetechs for the 442 and swap the shocks out on it. Both shocks are day/night compared to the Bilsteins to where you don't even have to think about it. For me, it was a 'Wow!" within the first 10 min of driving w them. From here out, I will bite the bullet and never go back. Just chalk it up to a baseline 'cost'. .
__________________
. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
#14
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So exactly how much did the new set of Ridetech shocks set you back, for those of us who might be considering switching to those?
It’s okay to tell us, we won’t say anything to your wife.
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1964 Tempest Coupe LS3/4L70E/3.42 1964 Le Mans Convertible 421 HO/TH350/2.56 2002 WS6 Convertible LS1/4L60E/3.23 |
#15
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I was impatient and ordered directly from Ridetech, they were $255ea.
If you shop it, you can get 10-25% off from what I've heard. Maybe more. It does not appear they rebuild like QA1 & Viking, but they have a 1 million mile warranty. I bought the QA1s direct as well, and they were $295ea. I suspect QA1/Viking will combine product lines due to the merger, will be interesting to see how that turns out. Also keep in mind these are current, post-'rona-high-inflation prices, and suspect they will return to more reasonable prices at some point. .
__________________
. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
#16
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Quote:
Quote:
Quote:
Call me skeptical, but once companies figure out they can get more money out of us, I doubt they're going back.
__________________
Ken '68 GTO - 464 - Ram Air II heads - 236/242 roller - 9.5” TSP converter - Moser 3.55 Truetrac (build thread | walk around) '95 Comp T/A #6 M6 - bone stock (pics) |
#17
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I thought the Ridetechs were rebuildable, I did a quick sweep on the site before I mentioned it and didn't find anything. And if it's a kit, even better. QA1 & Viking I believe you have to send them in for service.
I figured I could get a deal if I shopped, but there's a whole level of frustration I was working with at the time and honestly just wanted it out of the way. I'm not married, but I've been w my GF for a pretty long stretch, and she's supportive of my addiction. She actually understands too, and at times argues with me not to cut corners or time. I get the ''member what happened last time your did that..." . Once 'things' in general 'settle down' in this world, I believe the general competitive market thing we apply, and we will see some well-deserved, positive changes. .. But in general, I usually am skeptical as well... .
__________________
. 1970 GTO Judge Tribute Pro-Tour Project 535 IA2 http://forums.maxperformanceinc.com/...d.php?t=760624 1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car https://forums.maxperformanceinc.com...ght=procharger Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be |
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