427ci LS2 sleeved, dry sump oil pump, engine build & install, 69 Camaro

[DaleTx]

Originally Posted by PTAddict

Dale,

My '71 was originally set up with Hotchkis front and rear springs, Hotchkis/Bilstein shocks, Hotchkis front sway bar. It worked pretty well, but the rear dipped quite a bit on acceleration, and I didn't get the quite the drive off corners I thought I should. The CAT5 springs were quite a transformation - the rear dip was gone, the car really hooked off corners, and the overall feel was more stable and locked down. On the flip side, the ride was significantly harder on the street, but not enough that it bothered me.

The CAT5 springs use solid spherical bushings at the spring eyes, which eliminate twist along the long axis of the spring and thus in theory reduce leaf-to-leaf rubbing and binding. And they're very stiff in the front half of the spring, so the spring acts more like a control arm, doesn't wind up much at all, and has greater anti-squat effect. It all seemed to work very well for me, at least in that application.

As I said, on the 2nd gen I used the Bilsteins to begin with, and later switched to adjustable AFCOs sourced from Global West. The AFCOs were an improvement, but not huge. On my current '69, I use Detroit Speed double adjustables. I set them initially to the baseline that Kyle and Stacy gave me, and I've never had to move them more than one click from that baseline. That's one of the advantages of buying from a premium vendor like DSE - they've done almost all of the testing and experimentation I'd have to do myself.

Just my opinion, if it was me I'd go back to the Bilsteins for now, sort out what you want to do with the rear suspension, then work with a trusted vendor to see what shock package matches your combination and goals.

Scott... Thanks for all the great info! What you described with the rear end dipping on your 71 under acceleration is exactly what I am experiencing. Thanks for steering me to the Global West CAT-5 leafs. I called them today and placed an order for a set with 2" drop. They said the CAT-5's are a good set up for the track and will support HP levels of 600 to 700. I think this is a good next step for the suspension on my car. Also, I have done enough work on the car in the past year... and just want to enjoy it for a while now. Changing leafs will be a breeze compared to changing to a 4-link set up. Thanks for offering some great insight and solutions

Originally Posted by Sieg

Dale - I have Global West rear leafs, not sure how they compare to the new generation of part numbers. I just emailed them my part number (31-245-1) and asked them to translate my spring rate to their new part #'s. They're relatively stiff, I'd guess they're L2's.

You're more than welcome to drive my car if the springs end up being what you're considering.

Marc at SC&C is a wealth of knowledge, just be prepared to spend 45-60 minutes on the phone and have a notepad handy.

Thanks for the great info Sieg! Appreciate the offer to drive your car. I'm committed now... I'm not to much worried if the ride is a little stiff.

Originally Posted by Flash68

You guys all realize that Fox manufactures the shocks for Ridetech right? You know, the "must have" shocks of many of today's pro touring cars?

I believe that JRI's can be upgraded from single to the multi-adjustable with what you already have... can you do that with the Fox/Ridetech/Hotchkis? Just thinking out loud...

The CAT-5 is also an awesome leaf spring setup and about as good as it gets for leafs. Some killer cars run that.

Thanks Dave! appreciate the feedback on the CAT-5 leafs... can't wait to try them out.

Originally Posted by Sieg

Yes, as an old off-roader I've known Fox for years. But Fox, like with any good shock manufacturer, you're not going to get their best valving with their "entry level" performance line. I've also ran Bilsteins on a car (in the 80's) and there's something magical about the way their valving ramps up as you push the vehicle harder.

The KTM 300 Dale just picked up has exceptional suspension and I'm anticipating he'll expect similar performance from the shocks on his Camaro now that he's taken it to another level with a killer motor and trans combo he's exploited the chassis' weaknesses. IMO - He's ready for serious 3 way valving and another brake upgrade won't be too far off. In no way am I knocking Ridetech/Hotchkis/Fox as their 3-way products appear to perform well as do a few others. It's big money, but I've never regretted an investment in top-notch shocks.

You can make up for a weak motor with good brakes and suspension............with my limited experience it doesn't work the other way around.

Good to know regarding the GW Cat5's - Thanks

Sieg... I totally agree with you on this. Fox does make great stuff, but the shocks I got are "entry level", and designed to work under a wide range of applications and uses... I am very attuned to the handling on my car now after several years of tweaking, and I know they are just not quite what I was looking for... but that doesn't mean they won't be great for other applications. I am probably at that point where I need some adjustibility in a shock like you said.

I went back and read Carl C's post about the Hotchkis tuned Fox shocks and he said they worked great after some fine tuning by the guys from Fox. He made a comment that after the tuning, the shocks were "much more composed" so maybe he was also experiencing some bounce in stock form.

Originally Posted by GregWeld

Mary Pozzi seemed to do just fine with leaf springs...


Just sayin'

That works for me, new leafs on the way! ... I'm sure Mary could do quite well with just about any set up though, Lol

[Sieg]

Originally Posted by DaleTx

Sieg... I totally agree with you on this. Fox does make great stuff, but the shocks I got are "entry level", and designed to work under a wide range of applications and uses... I am very attuned to the handling on my car now after several years of tweaking, and I know they are just not quite what I was looking for... but that doesn't mean they won't be great for other applications. I am probably at that point where I need some adjustability in a shock like you said.

I went back and read Carl C's post about the Hotchkis tuned Fox shocks and he said they worked great after some fine tuning by the guys from Fox. He made a comment that after the tuning, the shocks were "much more composed" so maybe he was also experiencing some bounce in stock form.

No doubt those shock are a big improvement over the average shocks you'll find on most cars. Based on your input Carl probably had them ramp up the compression and rebound valving. You're going to want a shock on your car that has the adjustability of your KTM. With your natural attention to detail you'll end up with a menu of high/low speed compression and rebound settings for your favorite tracks, commuting, and sport driving. The only time you'll need to send shocks away is for routine servicing.

Looking forward to you input on the Cat5 system. Hopefully they improve lateral movement as advertised. Fair warning - the spring change in my car turned it into a drifter with the previous tires, the 200TW NT05's neutralized the over-steer tendency........with my baby motor.

[DaleTx]

Originally Posted by Sieg

Looking forward to you input on the Cat5 system. Hopefully they improve lateral movement as advertised. Fair warning - the spring change in my car turned it into a drifter with the previous tires, the 200TW NT05's neutralized the over-steer tendency........with my baby motor.

Global West said I should get the parts sometime next week... so once I get the springs in I will report back. Looking at the pictures they look very thick, 5 leafs instead of 3... I don't think I'll get any spring wrap with these. Not sure what to expect for the ride... but I like it on the firmer side.

Did you go with the 2" drop with the reverse eye, or the 1-1/4" drop with the standard eye? I went with the 2"... that's about what I have now.

[Flash68]

Originally Posted by Sieg

Yes, as an old off-roader I've known Fox for years. But Fox, like with any good shock manufacturer, you're not going to get their best valving with their "entry level" performance line. I've also ran Bilsteins on a car (in the 80's) and there's something magical about the way their valving ramps up as you push the vehicle harder.

The KTM 300 Dale just picked up has exceptional suspension and I'm anticipating he'll expect similar performance from the shocks on his Camaro now that he's taken it to another level with a killer motor and trans combo he's exploited the chassis' weaknesses. IMO - He's ready for serious 3 way valving and another brake upgrade won't be too far off. In no way am I knocking Ridetech/Hotchkis/Fox as their 3-way products appear to perform well as do a few others. It's big money, but I've never regretted an investment in top-notch shocks.

Good post.

Originally Posted by GregWeld

Mary Pozzi seemed to do just fine with leaf springs...



Just sayin'

Yeah. And then she went in and put in a 3 link..... hmmmm.

Originally Posted by DaleTx

I went back and read Carl C's post about the Hotchkis tuned Fox shocks and he said they worked great after some fine tuning by the guys from Fox. He made a comment that after the tuning, the shocks were "much more composed" so maybe he was also experiencing some bounce in stock form.

Yeah if only all of us couldn't get access to a test and tune day at the track where the Fox techs are there making all of the on-the-fly adjustments and changing out parts. That's some serious support right there.

[PTAddict]

Originally Posted by Flash68

Yeah. And then she went in and put in a 3 link..... hmmmm.

LOL. But the truth is, whatever we want to tell ourselves, 99% of us will never be able to drive close to level of Mary Pozzi. For the rest of us who just aspire to have fun and continually improve, we can go very far without going to the trouble and expense of radical re-engineering.

I was out at ORP a few years back with the Porsche club in my '71, stock subframe with scanc.com front suspension mods, the aforementioned GW leaf springs, AFCO shocks, Michelin PS Cup tires. My instructor, who was both an excellent driver and long time instructor, was stunned at how well my car worked on that very technical track. It was easily the fastest car in the intermediate class, which was populated mainly with late model 911s, Caymans, and Lotuses. Other drivers kept coming up between sessions, examining the car, asking about mods, etc. I'd have them crawl under the back end to see the big ugly solid axle controlled by nothing but a pair of huge old leaf springs, and they'd just shake their heads in wonder.

[DaleTx]

Originally Posted by Sieg

IIRCC - They didn't have the reverse eye when I purchased mine, and advertised 1.5-2" lower. I definitely recall being disappointed with how high the car was in the rear when I put it on the ground so it now has 1" spacers and 4* shims which put it close.



I imagine your ride will be quite a bit firmer if you were running stock springs like I was. With the stock spring the rear spoiler would excessively squat the rear above 100 mph creating a very light front end. That's not an issue with the GW springs.

Thanks Sieg. Now Global West offers the standard eye which is 1-1/4" lower stance, and the reverse eye which is 2" lower stance on the CAT-5 leafs. Looks Like the reverse eye should work good and still leave some room for shims to adjust the axle angle.. Thanks for the pics

Originally Posted by Flash68

Yeah if only all of us couldn't get access to a test and tune day at the track where the Fox techs are there making all of the on-the-fly adjustments and changing out parts. That's some serious support right there.

Carl's probably helping out with product development with his feedback so that cool. Good for Fox for being there.

Originally Posted by PTAddict

LOL. But the truth is, whatever we want to tell ourselves, 99% of us will never be able to drive close to level of Mary Pozzi. For the rest of us who just aspire to have fun and continually improve, we can go very far without going to the trouble and expense of radical re-engineering.

I was out at ORP a few years back with the Porsche club in my '71, stock subframe with scanc.com front suspension mods, the aforementioned GW leaf springs, AFCO shocks, Michelin PS Cup tires. My instructor, who was both an excellent driver and long time instructor, was stunned at how well my car worked on that very technical track. It was easily the fastest car in the intermediate class, which was populated mainly with late model 911s, Caymans, and Lotuses. Other drivers kept coming up between sessions, examining the car, asking about mods, etc. I'd have them crawl under the back end to see the big ugly solid axle controlled by nothing but a pair of huge old leaf springs, and they'd just shake their heads in wonder.

That's a great story... That is part of the fun with this hobby, to take an old classic, fix it up and hang with all the new stuff... good feeling.

Sounds like the CAT-5 leafs are a great set up.. can't wait to get them on the car and try it out.

[DaleTx]

I went to the historic races at PIR today and bumped into Sieg We spent some time talking to the mechanic and driver of this nice 1968 Z28.

This car won it's class by almost a full lap running against mostly Corvettes and Mustangs. This car was way faster than the other cars...the driver was on the edge at all times. The mechanic told me the engine runs up over 9K. It had a 4:56 rear axle and he went 155 mph down the main straight. I do have a video clip of it running wide open that I will post up later.











Dry sump tank in the trunk and a fuel cell...




I thought of Dave (Flash68) when I saw these side pipes... very cool...This car sounded amazing going down the straight!




Jerico 4 speed transmission




302 pumped to the hilt. The driver said it had over 500HP but would not give us the actual number. 5 stage dry sump pump, step headers, titanium valves, Holley carb.






I really liked this picture.

[Sieg]

Originally Posted by DaleTx

Global West said I should get the parts sometime next week... so once I get the springs in I will report back. Looking at the pictures they look very thick, 5 leafs instead of 3... I don't think I'll get any spring wrap with these. Not sure what to expect for the ride... but I like it on the firmer side.

Did you go with the 2" drop with the reverse eye, or the 1-1/4" drop with the standard eye? I went with the 2"... that's about what I have now.

IIRCC - They didn't have the reverse eye when I purchased mine, and advertised 1.5-2" lower. I definitely recall being disappointed with how high the car was in the rear when I put it on the ground so it now has 1" spacers and 4* shims which put it close.



I imagine your ride will be quite a bit firmer if you were running stock springs like I was. With the stock spring the rear spoiler would excessively squat the rear above 100 mph creating a very light front end. That's not an issue with the GW springs.