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Beer Geek
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Discussion Starter #1
Ritalin version:

Went to see 1stGOAT today. I was thinking @$2400 for four dampers and four springs I better get a dinner date with Jessica Simpson out of the deal. Five miles later (average to below average surface streets, even in SoCal), I was thinking, Jeez, I could have a set of these for only $2500. Just wow.

I need to upgrade my brakes before I buy any more suspension pieces. Right now I am going to go buy a lottery ticket, because all I have is a dollar and a dream. I wonder if I could get a set of Drummonds painted Carolina Blue instead of Duke blue.

Mark, I will be calling. It is a 'when' not 'if' thing.
 

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Ignoring the Speed Limit
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Um...



:D
 

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Discussion Starter #3
My lottery numbers for Wednesday night's $37,000,000 drawing are 19-33-35-44-47 with a mega multiplier of 24.

Do you want to run less than one degree of negative front camber for tire life AND run a compliant suspension for high mileage AND shoot apexs for fun?

Have you tried running -2.5° front camber, only to dump a grand on new tires every six months?

Have you tried tightening up your swaybars? Gone looking for roll stiffness so you could still corner on minimal camber? Been there done that? Had so much understeer you felt like Smith on the bridge of the Titanic?

Have you tried tried softening your bars back up and leaving your cambers minimal and tried stiffer springs instead? So now you can corner and your tires last, but you have a standing dental appointment Monday mornings?

Have you looked at Franken-fabricating the front subframe of a late model Camaro onto your Goat so you could run unequal length A-arms and an LS1 between a pair of 275mm front tires?

Still frustrated? Does it seem like all your money goes into tires, the dentist or psychotropic substances stored in double locked cabinets?

Try the Drummonds. Only $2500.
 
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swmn,

i know i'm not the only one with similar goals as you, suspension-wise. we've followed all of your threads, and respect and value the huge amount of research you've done in this area. are we to take the above comments to mean that, in your opinion, the drummond setup is that much better than the myriad of other solutions you ridden, driven, and mused over?

if so, it sounds like 1st goat is going to have an even longer line of people knocking on his door asking for rides, and drummond is going to have quite a few orders coming in soon. . .
 

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Discussion Starter #6
mixedxboy,

Thanks for your kind words. Really the two most important questions are the same two Mike White asked me and asks everyone else.

1. What are your goals?
2. What is your budget?

The Pedder's Street II for instance is a very nice, well integrated system. It is a very nice upgrade at a very reasonable price.

I dunno your goals. I put 19,000 miles on my 2004 just in calendar May and calendar June of 2006. Near stock ride quality is very important to me.

Right now I have every bushing in the Pedder's catalogue. I have fresh OE springs with about 2500 miles on them lifetime. My shocks and struts are near the top of the critical damping scale for the springs I am running. My HKS bars are cranked down as tight as I can take them for long highway trips. I am at 'near stock' ride quality, I have spent several thousand dollars, and I can't believe how good the thing handles.

It becomes incremental, I spend more and more money for smaller and smaller gains. I really expected the Drummonds to be my limit. I expected them to be noticeably better, but $2500? Come on. I was pleasantly suprised in an expensive sort of way, if you know what I mean.

But if you drive a lot of miles (or want to maintain near stock ride quality for some other reason), and you don't want to tear up expensive tires in a big hurry, and you like the twisty two lanes when you have some free time; lets pick it apart.

As much as I love my GTO, she came from the factory with two major flaws.

#1, typical GM rubber bushings. I have read up on bushings a little. Urethane is pretty much urethane. There is some really neat tricks you can do with the stuff. To use it as automotive bushings the durometer of the stuff is going to fall in a relatively narrow range, but it is almost as cheap as dirt, it works good and it lasts pretty good.

You can look at Ultra High Density something something Polymer if you have money to burn, and there is Delrin at the top of the durometer scale. I suppose you could have a set of bushings made out of chrome-moly steel if you wanted...

But bushings do two things. They isloate the driver from NVH and they maintain the spatial relationships between suspension components while the vehicle is in motion. So what do you want? For maximum isolation from NVH stick with the OE rubber. For maximum ultimate cornering ability go with the Delrin or chrome-moly steel. Urethane is an excellent three way compromise between NVH, ultimate handling and price.

So where do you start and where do you stop? On the 04/05/06 GTO you start with front radius rod bushings, rear X-member bush and front strut top bushes. My car is a rolling testament that you can do every bush under the car in urethane and still maintain near stock ride quality.

2. The other 'problem' with the GTO is we get a strut type front suspension. Strut type suspensions are cheap to manufacture, and they don't take up much room. But, it is very difficult to run oversized tires, and camber is fixed.

Even if you install megadollar special golden bushings made by magic elves, you are going into every corner with fixed front cambers. So what happens?

As weight transfers from side to side in a corner the inside side of the car rises a little bit and the outside side of the car drops. Your front cambers are fixed, relative to the floorpan, which means the outside front tire -relative to the road surface- is more positive than it was with the vehicle parked; and the inside front tire camber - relative to the road- is now more negative than it was parked.

Your tire has the best lateral grip when the tire and wheel is vertical - biggest contact patch that way. So you can dial in a bunch of negative camber. That way as the car rolls side to side in corners the outside front, the one with the most weight on it, gets to be about vertical, gives you maximum grip and highest cornering speed. But running alot of negative camber in the straights wears out your tires in a hurry.

So you could mess with roll stiffness instead. Stiffer front springs will reduce the amount the car rolls in corners, but the ride gets firmer in the straights.

You could dial the front sway bar up stiffer. If you do that, you can either A) dial the rear sway bar up stiffer too and kiss your sweet ride goodbye, or B) leave your rear sway bar untouched, introduce bias in softness towards the rear axle and find Understeer the way some people find Jesus.

Or you can do all those things, put everything back to where it works good together and be where I am now. If the speed limit sign says "55 MPH limit" I can plan on setting the cruise at 88 mph and the suspension waking up enough to make some coffee. No sweating, just wandering around in slippers and a bathrobe.

But it is so easy there has to be more. I have the handling potential of the chassis unlocked, but I am no where near maximum.

So I looked at as LS1 F-body by accident on purpose. Just stand in front of your goat, hold your hands shoulder width apart over the middle and say "LS1". Then spread your hands a little more and say "Unequal length A arms", then spread your hands a little more and say "275mm front tires", then spread your hands a little bit more and say "stock GTO sheet metal".

Unequal length A-arms are going to give you camber that changes as the body rolls. If the geometry is good you can run say -0.1° front camber on the straights, and keep your front tires just about vertical in corners as the body rolls. I am working on it. No immediate plans to hack one up, but I will be posting up the math in a week or three.

Drummonds are super cheap compared to that fabrication job. I got some PMs out I am waiting for responses on before I go on.

What are your goals?

What is your budget?
 

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Have Bar, Will Travel
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Some great points Swmn. However I would sum all of that up to, How close to a built race car do you want to get?

The main reason I'm interested in the coil overs is so I can dial them up for a track day, then dial them down to daily drive. I don't think getting 275's up front is the complete answer. I am more concerned with getting 275+ on the rear so we can put the power down. If I could get 315 or more at back I would consider 275 for the front.

But as with all car mods, it comes down to personal preference and monetary tolerance. From what I read I think you and I have some similar goals and ideas.
 

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Ignoring the Speed Limit
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swmn said:
You could dial the front sway bar up stiffer. If you do that, you can either A) dial the rear sway bar up stiffer too and kiss your sweet ride goodbye, or B) leave your rear sway bar untouched, introduce bias in softness towards the rear axle and find Understeer the way some people find Jesus.
Buahahahahahahaha!



Classic.
 

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Discussion Starter #9
Napalm said:
However I would sum all of that up to, How close to a built race car do you want to get?
An excellent, elegant synopsis.

Napalm said:
The main reason I'm interested in the coil overs is so I can dial them up for a track day, then dial them down to daily drive.
It is one way to skin the cat. More power to you and stuff, I am not actually going to disagree with anything you posted.

All the ones I have looked at have linear rate springs, so once the ride height is dialed in with the dummy on board using the spring perches all that is left to do is adjust the compression rate and the rebound rate as desired within the critical damping range of the known spring.

I can see pushing the top of the critical scale on compression and rebound for track days and backing the hydraulics back off for everyday street use, but I am not convinced moving the spring perches around is going to 'do' anything outside of messing up the ride heights that took so long to get dialed in in the first place. A coil over setup with a variable rate spring would be a different story maybe.

Also, I can look to my adjustable sways for roll stiffness on track days that I would not tolerate for use on public roads.


Napalm said:
I don't think getting 275's up front is the complete answer.
I agree, but it is a step in the right direction. As crappy as the OE 04 brakes are, the factory system is strong enough to activate the ABS with OE tires. And somebody (I am tracking an unusual number of threads right now, but somebody) pointed out in the last couple days that the front tires are the limiting factory in cornering adhesion. I agree with 'somebody', whoever you are. Sorry your user ID is buried in my bit-bucket right now. Props.

Napalm said:
I am more concerned with getting 275+ on the rear so we can put the power down. If I could get 315 or more at back I would consider 275 for the front.
Yup. I was thinking 305s at the rear would make me happy for a while.

Napalm said:
But as with all car mods, it comes down to personal preference and monetary tolerance. From what I read I think you and I have some similar goals and ideas.
This is exactly right. I think we do have similar goals and similar ideas, but we are going about it different ways. With history as my guide it will be 20-40 years before the General produces another car I like this much. So I want to get this right.

I am not worried about making power. I am doing the motor last because I have been down this road before. What I am doing is getting the car ready for the next motor before the next motor goes in.

At this point I have a really good idea that I am not going to be able to build the car out past 600fwhp without compromising something major.

At 500fwhp I have a pretty good shot of having an integrated well mannered car, on comfortable suspension, dependable motor and quiet exhaust.

Tires is the remaining problem I think. 245mm rear is not going to cut it, at 500-550fw, 275mm might be OK. Even at "350-375" fwhp, with the suspension I have I am going to start running out of tire soon, front and rear. I think all I really need to run out of tire tomorrow is to grow a pair.

With a Franken-Camaro front cradle I could do 500, even 550 fwhp all motor with an aluminum block and get 275mm tires at all four corners. Even 15 year old boys who know it is a GTO and wish they owned one would not be likely to notice I was running an extra 30mm of contact patch under stock sheet metal at all four corners. I haven't actually run on the street for cash in 25 years, but even the idea of putting something like that over on the unsuspecting is thrilling. I wonder if I could grab a Firebird radiator to make room for WS6 nostrils at the same time? Nobody would be looking at my tires then, they would be looking at my mullet.


Groucho said:
Strike a nerve did we Captain Smith?
 

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Discussion Starter #11
DMS North America said:
swmn, did you head back to 1stgoat's by chance for a third ride with the DMS 40mm ?
-mark
I am letting him tinker with it a little more, but I will. He alluded a couple weeks ago to some kind of sway bar end link something that I haven't heard the end of yet.

And I am not seeing the Drummonds as competition to Pedders. A set of four Pedders springs and GSR dampers is about $930 plus shipping plus installation. The same 8 pieces from Drummond list at $2,899 plus shipping plus install.

For the price Pedder's is great stuff. The Drummond's are just the sort of technological leap that make me check to be sure my glasses have been clean all along.

Looking back on the ride I took with 1stGOAT a couple weeks ago I still can't get over it. The car has not been corner weighted, and he doesn't know his ride heights. Excuse me, he knows it sits taller now than it did on his last set of drop springs, but lower than it did on the first set of drop springs.

No idea of relative height left to right on either axle, not even a wild guess on wedge/dewedge. 1stGOAT is a very smart guy, it is not that he can't figure this stuff out, he just hasn't.

He basically just opened the boxes and bolted the stuff to his car with everything adjusted to the 'middle'. And the car is mind boggling. Just mind boggling. He is making 500+ and 500+ at the rear wheels, and the car just doesn't squat under throttle. But it soaks up little bumps like nobody's business.

I am going to guess the majority of GTO owners are going to be justifiably happy running Pedder's coils and dampers at all four corners. To build a better system is going to take a lot of technical know-how and cost a few (quite a few) bucks, but Drummond did it.

Drummond is offering an incredible amount of roll stiffness with an amazingly compliant ride. It is taut, just like 1stGOAT said, taut. Very taut. But pleasingly taut like a snare drum head, not brutally taut like a gibbet.

Honestly I think it is more reasonable to compare Drummond's to fabbing in unequal length A-arm front suspension, rather than Drummond v- Pedders. A double wishbone front, done right, is going to take 4 horizontal tubes in the engine bay. The lower two can replace the existing engine cradle and locate the lower arms, the new two will be just below the hood line to locate the upper arms, and those four will have to be boxed out at the front.

And that whole snout will have to be attached to the firewall. A cross piece under the floor pan will be easy enough, but the upper tube is just not going to fit in the engine bay, so we are looking at taking the whole dash out to fab a cross tube around the HVAC unit and welding through the firewall. The good news is this is a good time to finish the roll cage, the bad news is a full cage will be optimum to locate the front and rear suspensions to each other in 3-D.

There is a $5000 bill at the welding shop, but the only thing forward of the firewall installed on the car is one layer of black paint and some custom fabbed tubing, and the entire interior of the car is in the spare bedroom. So then we go pick up a donor F-body or C5, and try to fit stuff like the PCM and battery back under the hood...

I am looking forward to taking another ride, but I am going to wait until he is through the current round of tinkering. It is all about keeping the front cambers under control, and besides listing for 'only' $2900, the Drummond's do leave all that room under the GTO hood for juicy bits like FI.
 

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Sold August 10 2007
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More tinkering coming.... cradle align, full realign, install rear raidus rod bush, install inner control arm bush, steering bush, Whiteline front endlinks....... so far we literally slapped the Drummonds on, set them to mid settings as suggested by Mark and let her fly to see where I wanted to go. My experience so far is that I don't want to make any huge changes and love the Drummonds.

The suspension has now settled and need to go back for an alignment and in the interim I have acquired more stuff to add, as is my practice (never leave well enough alone it could be better).

Wed the car will have the new stuff installed, cradle align, full 4 wheel align and the shocks and coilovers adjusted for daily driving. I will keep everyone updated but.... the news is.... if you buy the Drummonds you will be very happy. This is one of those cases where the price is absolutely justified if not a bargain considering the end result.

I am stll offering rides to anyone that wants to come check out the Drummonds.
 

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GTO no more baaah!
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Nice adjustable coilovers & adjustable sways :FTW:

Makes me want a 2nd GTO... oh wait, *twist* there we go!
 

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If anyone is around at SEMA this week, would be happy to chat. Please e-mail me setup a meeting (I will not answer my mobile in a middle of a conversation) [email protected]

Cheers guys, and thanks for the kind words. I will also be at las vegas speedway tomorrow afternoon.

-mark
 

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I am thinking strongly about the drummonds now. I am trying to work out something with autoform to basically either cutout the wheel wells and move the shocks to accomodate fatter tires and add the drummon kit along with bushings, sways, etc. It's time to get serious about suspension and I think the drummond kit is top priority on my list, second to backhalfing the car.
 

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;) looks like we are turning heads?
As I (DMS North America, not the factory) is still gathering our own info on what you guys are doing with these cars, I am happy to see what type of setups we are best suited for. The GTO crowd is not like the evo or honda guys at all, so I really want to make sure that everyone knows what they are getting and why!
Cheers,
-mark
 
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