Gerst Dominator Series 4 Link

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Pro's and con's aside, it looks lIke a throw-down race piece...very nice

you must of moved to a bigger shop too.....now you can move that car in and really get to work.
Car is cut to pieces lol, I figured out that you need about 3 times the room once you take a car apart then you thought you did lol
 
Yes Joe, unfortunately a stock gas tank is pretty much vetoed, there just simply isn't room,on most A bodies, I've tried several designs to get it to fit, the strange thing is, and I have no explanation for, I have a 71 dart, and 71 duster, on the duster, there's almost 3 more inches between the tank and the pumpkin, than on my dart, so while it may squeeze into the duster, it won't on my dart, and I've checked to make sure axle locations are identical, so this was something new to me, and both have 8.75 rear ends, so if anyone knows why that is, I'd love to know! Anyway, as I go on designing, I may make a provision in the crossbar for exhaust, I think it's very feasible to do, unfortunately, with a suspension like this, they just didn't leave much room to work with.


difference in gas tank size perhaps? I'm guessing this is why: From what I found online, theres 3 different gas tanks used from 70 to 76 in a bodies. an 18 gal, a 16 gal and a 16 gal with front vent tube
 
ok miss read that part.. but info is still false. and false info hurts your credibility...

Uses stock locations to bolt in, not compatible with inboard relaction kits meaning wider tires arent possible.

1) yes wider tires are possible. like i stated from personal experience. can get almost a 2" wider tire using the street lynx over leaf springs. both being bolted into the stock location.

2) i know for a fact you can relocate the lower bars by using the spring re-location kit. plus it says it right on the web site..

Get rid of your poor-performing leaf springs with our
Street-Lynx trangulated 4-bar system. By separating the locating
system from the spring, it's possible to drastically improve geometry, traction, and handling
while using a much lighter spring and shock to provide excellent ride quality and wheel control.
Our system requires no cutting to weld in a single crossbar between the factory
frame rails. Coil-overs mounted ahead of the axle eliminate wheel hop normally associated with
4-bar systems, yet allow stock gas tanks to fit, as well as TTI's off-the-shelf tailpipe kits.
Lower links bolt into stock leaf spring location with the included adjustable front mounts, or
links can be used in conjunction with standard inboard relocation kits and mounted under the frame
rails for increased tire clearance.
Includes Viking Double Adjustable shocks, standard. Axle housing not included.
Choose rear axle type you'll be using - 8.75/ford 9 allows TTI tailpipes, Dana 60 will not allow tailpipes.
Shipped with our recommended spring rates and free shock adjusting wrench.
 
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First, I never said mini tub. not sure where you got that from? 2nd, both the QA1 6 link and the streetlynx mount to the front spring perches, which would place the bars outside of the frame rails. You'd only gain the difference between the width of the spring and the bar diameter. Unless you moved the per mounts inboard. At least, that is from what my research shows.

This is also noted on RMS's own website:

"The lower links attach to the axle with u-bolts, in place of the leaf springs. The front of the lower links also have the same dimension as leaf springs, so the system will bolt in at the stock leaf spring location, or, if the MP inboard spring relocation is used, the lower links will bolt in that location as well."

Welcome to Reilly MotorSports, Inc.
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and now ya say you can use the spring re-location kit... see the issue? your first post says you can't use a spring re-location. this post right off the rms site clearly states that you can use a relocation kit.


look i'm not trying to bust your balls here. its a neat looking kit that i hope works well for you. but some of your information is clearly wrong and you are posting it here as fact. makes me question the accuracy of the information on the other kits you posted about. all that does is hurt your credibility and makes you look like a gts commercial. do ya see where i'm coming from here?




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A few people have been asking me about my rear suspension, i should have the thing installed in the coming weeks as i get free time from 2 kids under the age of 3, so pics will be uploaded as I go. In the short term, I thought i'd discuss why I chose the kit I'm going to use. I'll also try to answer any questions you may have. Keep in mind, I dont claim to be nor am I a suspension expert. I have a working and practical knowledge is all.

Now before I get into why I chose or decided against one kit or another, this is just my opinion, what works for me may not suit your needs or vise versa. This post is not design, meant or implied to sell or not sell a kit. I am merely stating my reasons upfront for my choice, I am not putting down any other kit or maker. I am listing the retail prices by each as well. But mainly because cost does play into every decision. What I will do, is attempt to thoroughly explain my choice, I will answer any questions to the best of my knowledge, however what I will not do, I repeat, what I'm not going to do is to debate one maker over the other, as what happened the last time I posted my front kit. If you wanna turn something into a mud slinging contest, go join Hillary's or Donald's campaign team. Also, I promise to have typos, it happens, especially with autocorrect haha. If you are good with that, continue reading, if not, dont bother reading on.

First I listed some requirements:

Had to be adjustable and suitable for road racing, drag racing, street
Had to be easily tunable with multiple tuning features
Be cost efficent, bang for buck
Use at minimum dual adjusting shocks
Allow for the maximum width tires possible without backing halving
Ajustable ride height
Allow for corner balancing the car
Allow me to keep my rear seat

So lets look at my options:
Mopar SS springs, sway bar and Dual adjusting shocks.
RMS Street Lynx
QA1 6 Link
Magnum Force Pro Link
Control Freak 4 Link (parallel with pan hard)
Custom

Option 1: Mopar SS Springs, rear sway kit and dual adjusting shocks(vikings, qa1?)

Pros:
Tried and true long time upgrade for Mopars
Cheapest option
Easiest to install

Cons:
No adjustability other than the shocks
Only 2 spring rate options
Requires a spring relocation kit to fit wider tires
No ride height adjustment
Cannot corner balance

Cost: 920 with shocks, sway and springs( not counting relocation kit)

Decision: No go, must have more adjustment

Option 2: RMS Street Lynx

Pros:
Popular upgrade.
Some tuning features
Dual adjusting Coil Overs

Cons:
Trianugluated 4 Link means limited adjustability.
No Sway Bar
Requires spring relocation kit to get wider tires

Cost: 1995
Decison: No Go, while it has some adjustability, very limited with a triangulated 4 link.

Option 3: QA1 6 link

Pros:
Adjustable Coil overs(3 options)
Bolt in
Adjustable rid height(1 in +/-)
Sway bar

Cons:
Bind central, just dont see how this works to improve handling let alone without binding
Expensive, most expensive of any kits
Heaviest option, the added parts to make this a 6 link add weight.
No need for 2 rear ward links
Keeps the roll center in the high, non adjustable position
Uses stock locations to bolt in, not compatible with inboard relaction kits meaning wider tires arent possible.

Cost: 2995.00(Single adjustable coilovers); 3195 (dual adjusting); 3895 (4 way adjustable)

Decision: No go, too expensive and just offers no real advantages in performance or tuning over a 4 link.

Option 4: Magnum Force Pro-Link

Pros:
Adjustable in alot of areas but roll center and ride height are not
Choice of panhard bar or watts link.
Mounts inboard of frame to allow much wilder tires

Cons:
Location of watts link puts the roll center high above the rear axle, chosing the panhard would help this but panhard isnt adjustable
Roll center is high and non adjustable.
Doesnt come powder coated but they will for an extra 500 bucks
2nd most expensive kit
Magnum force's reputation
No Sway bar option

Cost: 2574 bare with dual adjusting coil over shocks, 3069 powdercoated with same coil overs

Decision: No Go, high roll center would actually work against my front suspension, creating an unpredictable roll in high speed corners


Option 5: Control Freak Rear suspension Parallel 4 Link with Panhard bar

Pros:
Adjustable with pan hard(though limited on the panhard)
Dual Adjustable coil overs standard.
Parallel 4 link allows for road racing, drag racing and street driving.
Adjustable ride height
Sway bar option(329+)
Allows wider tires
Complete, powder coated ready to go kit

Cons:
Very hard to think of any here, so I had to split hairs.
While the panhard bar is adjustable, I'd prefer slots to get a finer tune on the panhard bar but I'm splitting hairs so i wont count this in my decision.
The pan hard bar allows the rear to move slightly along a curve bias, therefore, while wider tires are allowed, still need to run some clearance to ensure they dont rub the frame or quarters.

Cost: 1899 without sway bar, 2228 with sway bar

Decision: Go, adding to the consider list. With only one negative I can find with it, definity fits the bill for what I need.

For option 6, Originally I started out to design and build my own. While I can fab and weld and have the tools to do so, my skills aren't up to the level I trust enough with my life or the lives of those with me. Since I lack fabrication skills to this level, I decided to give Carl Gerst a call, give him my requirements and see if he could come up with something that would work. When I called, I spoke with him for over an hour, came to learn that he had already been working on a rear system for the past several months and that it was almost ready to go public with it after a few more tests. As he rattled off the features he was building into it, I was stunned. I just didnt think it'd be possible to fit all that into an A body.

Option 6: GTS Dominator Series 4 link with Watts link

Pros:

Adjustable links, links feature different height and angle options allowing a user to fine tune the links to the driver and track
Adjustable ride height
High travel, dual adjustable coil over shocks.
Links mount inboard of frame and allows for much wider tires than stock
Watts link is centered in the rear of the axle, just behind it and features 8 inches of adjustable roll center adjustment
Watts links are also tunable.
Very cost effective, cheapest of the adjustable 4 links with sway bars thus far., 3rd overall in price behind Option 1 and 2.
Sway bar included
Watts link allows the rear to move up and down straight, meaning less clearance needed for the tires, allows just that much more tire or to use spacers to help tune track width.

Cons:
Very hard to come up with any here
So much adjustment, I'll probably get myself in trouble lol

Decision: Go, add to consider list. I may be biased after having his front kit, but this rear kit knocked my socks off.

The sheer amount of adjustment is amazing. This kit will allow me to fine tune my car not only to my liking, but to the track.

Final Thoughts:

This was a tough call between the Control Freak And the GTS. Both of these kits met all my requirements and then some.

Both had very few to no cons. Price being about the same, the GTS does have the most adjustability as well but this ultimately boiled down to having a matching setup plus the uniqueness and tunability of the GTS. So I went with the GTS Dominator Series

View attachment 1714948594

View attachment 1714948595

also not being able to run a wider tire without mini tub on the triangular 4 link is wrong. you can go wider then with leaf springs no doubt... i was running a 275/50-17 (damn close to 11" wide) on the rear of my dart with a triangular 4 link. quite a bit wider then a 225/50-17 (close to 9" wide) that is super close to the leaf springs. thats a pretty good difference.. no?

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and now ya say you can use the spring re-location kit... see the issue? your first post says you can't use a spring re-location. this post right off the rms site clearly states that you can use a relocation kit.


look i'm not trying to bust your balls here. its a neat looking kit that i hope works well for you. but some of your information is clearly wrong and you are posting it here as fact. makes me question the accuracy of the information on the other kits you posted about. all that does is hurt your credibility and makes you look like a gts commercial. do ya see where i'm coming from here?




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ok i see ya fixed the original post.. thank you for doing so.. the proper information is critical..

actually, I've said that from the very beginning, I've not edited my original post at all. Try reading next time.

Also, you can verify this by looking in the lower right corner of the post, see this post for example, it'll show the date and time it was edited.

point1.JPG
 
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ok miss read that part.. but info is still false. and false info hurts your credibility...



1) yes wider tires are possible. like i stated from personal experience. can get almost a 2" wider tire using the street lynx over leaf springs. both being bolted into the stock location.

2) i know for a fact you can relocate the lower bars by using the spring re-location kit. plus it says it right on the web site..


again, you need to take a remedial course in reading comprehension.

You're quoting 2 different parts of my post and trying to run them to fit your agenda.

RMS is compatible. I've said that all along. It's the QA1 that is not. I personally called them and asked when I spoke with them. So dont quote my writeup about the QA1 and then try to say I said that about RMS, which I did not. That's your problem
 

Option 2: RMS Street Lynx

Pros:
Popular upgrade.
Some tuning features
Dual adjusting Coil Overs

Cons:
Trianugluated 4 Link means limited adjustability.
No Sway Bar
Requires spring relocation kit to get wider tires

Cost: 1995
Decison: No Go, while it has some adjustability, very limited with a triangulated 4 link.

Option 3: QA1 6 link

Pros:
Adjustable Coil overs(3 options)
Bolt in
Adjustable rid height(1 in +/-)
Sway bar

Cons:
Bind central, just dont see how this works to improve handling let alone without binding
Expensive, most expensive of any kits
Heaviest option, the added parts to make this a 6 link add weight.
No need for 2 rear ward links
Keeps the roll center in the high, non adjustable position
Uses stock locations to bolt in, not compatible with inboard relaction kits meaning wider tires arent possible.

Cost: 2995.00(Single adjustable coilovers); 3195 (dual adjusting); 3895 (4 way adjustable)

Decision: No go, too expensive and just offers no real advantages in performance or tuning over a 4 link.

ok miss read that part.. but info is still false. and false info hurts your credibility...

Here, I bolded it for you. Can you find it now?

As far as my credibility, you making **** up and trying to say I said mini tubs first, then you change to trying to say I was wrong on the RMS, which Im not, then you try to say I changed my OP, which site records say otherwise.... hmmm who has the credibility issues? Seems to be YOU
 
Yes Joe, unfortunately a stock gas tank is pretty much vetoed, there just simply isn't room,on most A bodies, I've tried several designs to get it to fit, the strange thing is, and I have no explanation for, I have a 71 dart, and 71 duster, on the duster, there's almost 3 more inches between the tank and the pumpkin, than on my dart, so while it may squeeze into the duster, it won't on my dart, and I've checked to make sure axle locations are identical, so this was something new to me, and both have 8.75 rear ends, so if anyone knows why that is, I'd love to know! Anyway, as I go on designing, I may make a provision in the crossbar for exhaust, I think it's very feasible to do, unfortunately, with a suspension like this, they just didn't leave much room to work with.

difference in gas tank size perhaps? I'm guessing this is why: From what I found online, theres 3 different gas tanks used from 70 to 76 in a bodies. an 18 gal, a 16 gal and a 16 gal with front vent tube

Dart's have a 111" wheelbase, Dusters have a 108" wheelbase. So as Joe pointed out that's exactly the 3" difference. It's not the tank, it's just the wheelbase of the car.

Not using the stock tank is a pretty big drawback, and I don't even care about not being stock. I'm not a big fan of having the fuel inside the car, regardless of it being in a fuel cell. And the loss of trunk space is a problem. That's actually the biggest issue for me, I use my trunk because I use my car as my daily driver. And since it is a driver I would need a large fuel cell too, anything much less than 16 gallons would be a PITA on long drives.

Still interested in seeing the rest of the installation. I would love to get a measurement from the axle to the back side of the new crossmember though.
 
Dart's have a 111" wheelbase, Dusters have a 108" wheelbase. So as Joe pointed out that's exactly the 3" difference. It's not the tank, it's just the wheelbase of the car.

Not using the stock tank is a pretty big drawback, and I don't even care about not being stock. I'm not a big fan of having the fuel inside the car, regardless of it being in a fuel cell. And the loss of trunk space is a problem. That's actually the biggest issue for me, I use my trunk because I use my car as my daily driver. And since it is a driver I would need a large fuel cell too, anything much less than 16 gallons would be a PITA on long drives.

Still interested in seeing the rest of the installation. I would love to get a measurement from the axle to the back side of the new crossmember though.


I dont like having the fuel inside the car either and the rules of the league I'll be running in say you can't either. So what I'm doing is cutting out the spare tire well and dropping a fuel cell that is 22 gal between the rails. I'll be building a fully enclosed cage with a removable top. The class I'll be in requires this regardless so it'd have to be done. I wasn't gonna keep the spare tire well anyway, so its not something I concerned myself with. I realize that'll be a turn off for others though.

as for the width of the crossmember, i measured 3 and 9/16 inches overall thickness. I checked my buddy's 70 340 duster, all original 340/727 8.75 rear car, i got 4 inches from the tank flange to the axle. So it MAYBE will fit, it'll be tight if it does. I'm junkyarding this weekend at a yard with a bodies so I'll try to remember to measure on some more just to check.
 
I think you could section a stock gas tank for clearance if necessary. I couldn't see losing that much capacity.
 
I think you could section a stock gas tank for clearance if necessary. I couldn't see losing that much capacity.

Sectioning a fuel tank is a colossal pain in the butt. The original tanks are dual layer, so, that's pretty much a non-starter if you really have an original tank. If you have an aftermarket single wall tank it has to be boiled out at a radiator shop to allow welding on it if it's had fuel in it. Yes, you can redneck it and hope it doesn't blow up, but that's your problem because I'm not welding on anything that used to hold fuel unless its been properly treated. Then you have to lay down a perfect, fuel tight weld. Then you should have it pressure tested to make sure you're actually right about that weld before you fill the tank with fuel. Since water has larger molecules than fuel, even pressure testing with water might not reveal all of your possible leaks. And when you're all done, you've screwed up the zinc coating they put on the tanks to keep them from rusting, so, you either have the tank re-treated or sealed so the weld doesn't rust. Most gasolines contain alcohol and are oxygenated, so the alcohol sucks up moisture and the untreated metal will rust in no time flat.

Oh, and and zinc coating has to be stripped back from the area of the weld on both sides prior to welding, you do not want to breathe zinc fumes. Search "metal fume fever" if you don't believe me.

Honestly, it would probably be easier to fabricate your own fuel tank than section an old one.
 
Sectioning a fuel tank is a colossal pain in the butt. The original tanks are dual layer, so, that's pretty much a non-starter if you really have an original tank. If you have an aftermarket single wall tank it has to be boiled out at a radiator shop to allow welding on it if it's had fuel in it. Yes, you can redneck it and hope it doesn't blow up, but that's your problem because I'm not welding on anything that used to hold fuel unless its been properly treated. Then you have to lay down a perfect, fuel tight weld. Then you should have it pressure tested to make sure you're actually right about that weld before you fill the tank with fuel. Since water has larger molecules than fuel, even pressure testing with water might not reveal all of your possible leaks. And when you're all done, you've screwed up the zinc coating they put on the tanks to keep them from rusting, so, you either have the tank re-treated or sealed so the weld doesn't rust. Most gasolines contain alcohol and are oxygenated, so the alcohol sucks up moisture and the untreated metal will rust in no time flat.

Oh, and and zinc coating has to be stripped back from the area of the weld on both sides prior to welding, you do not want to breathe zinc fumes. Search "metal fume fever" if you don't believe me.

Honestly, it would probably be easier to fabricate your own fuel tank than section an old one.

Thank you, I do understand the hazards and issues associated with sectioning a gas tank and even welding around galvanized/zinc coated steel. If I were to do it I would start with a new reproduction tank at the very least. I was merely trying to offer a solution to the issue.
 
Dart's have a 111" wheelbase, Dusters have a 108" wheelbase. So as Joe pointed out that's exactly the 3" difference. It's not the tank, it's just the wheelbase of the car.

I think he said there was 3" more room on the shorter wheelbase Duster, which doesn't make sense. That would be a head scratcher for me.
 
I think he said there was 3" more room on the shorter wheelbase Duster, which doesn't make sense. That would be a head scratcher for me.

It makes perfect sense. The axle is 3" further forward. The tank isn't. :D

Where it starts to get confusing is that they both use the same frame rails, springs, trunk pans etc. So, I'm not sure why they're different at all with regard to the axle to tank distance. I was under the impression that the difference in wheelbase length was in front of the rear frame rails. But if that was true the axle to tank distance would be the same on all of them regardless of body style. I may have to take some measurements, since I have both cars.
 
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It makes perfect sense. The axle is 3" further forward. The tank isn't. :D

Where it starts to get confusing is that they both use the same frame rails, springs, trunk pans etc. So, I'm not sure why they're different at all with regard to the axle to tank distance. I was under the impression that the difference in wheelbase length was in front of the rear frame rails. But if that was true the axle to tank distance would be the same on all of them regardless of body style. I may have to take some measurements, since I have both cars.
thats what i was wondering. which is why i suspect the gas tanks themselves, being the 3 different types
 
It makes perfect sense. The axle is 3" further forward. The tank isn't. :D

Where it starts to get confusing is that they both use the same frame rails, springs, trunk pans etc. So, I'm not sure why they're different at all with regard to the axle to tank distance. I was under the impression that the difference in wheelbase length was in front of the rear frame rails. But if that was true the axle to tank distance would be the same on all of them regardless of body style. I may have to take some measurements, since I have both cars.

You should take some measurements. I agree; I though the difference is in the floorpans between the front and rear subframes, particularly in the rear footwell area. If that's the case, gas tank clearance should be equal across the board with the same tanks.
 


well apparently I'm not the only one who liked this kit.
 
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