Four-Link Altered?

I've never been afraid to expose my ignorance in order to learn something, so here goes. Does anyone run a four-link setup in a blown alcohol 125" altered or are they all hard tails? If the four-link simply doesn't work...why not? Where is the performance limit (in terms of 1/4 mile ET) where a hard tail becomes necessary as opposed to a four-link? Is one more prone to tire shake than the other? This would be a 125" 23T bodied altered with a short stroke/large bore 446" BB Mopar wedge. SSI 1471 std. helix at about 20% over. JW cased glide with 1.80 first gear. Chassis would certify 10.2 (6.00 sec. and slower) regardless of rear setup. Will need to run 7.00 in quarter.

Thanks to any and all who respond! Any info on this subject would be greatly appreciated! Mark.

 

the thing that bothers me about the four link car is setting over a drive shaft that has U-JOINTS i would think if it didnt bottom out on the shocks it might work ok with only a certin amount of horsepower a four link bar sticking in you leg from a broken hyme joint are a U-JOINT in your ass could be little painful i think just my thoughts

 

Four-Link Altered

Jim...thanks for breaking the ice on this. ANYTHING in my ass, much less a u-joint, doesn't sound like much fun. There are, however, altereds running Top Dragster with big-inch nitrous motors that make about as much grunt as a blown alky setup. And the Pro Mod guys deal with u-joints and four links every day. I'm thinking there has got to be something more to this. Anyone else??? I'd REALLY like to hear some more opinions. Thanks for your time, Mark.

 

I've seen and raced with 4-link altereds with blown motors. The Top Dragster altereds are usually 150" wheel base cars and that makes a huge difference. The shorter wheelbase with a lot of horsepower is just very unpredictable. We already know these altereds will go which ever direction they want as a hard tail, and the suspension makes that even worse. The last 4-link car that I saw run with a blown setup spent more time going right or left than it did straight down the track. I think the hard tail is the most consistent with a large amount of power.

 

Four-Link Altered

Now we're getting somewhere! Thanks JT. That's what I was expecting to hear but It's good to have that confirmed. Thanks for your time, Mark.

 

If I were starting from scratch again I would most likely have a rigid hard tail chassis. However, we have successfully ran our altered with a four link susp. at low 6 second et's and over 220 mph in the quarter with no problems. As far as it going straight, well the car went as straight as any altered could go. Also we have a 150" chassis. The advantage I have always seen to being a hard tail is the chassis is lighter but if you know what you are doing with a four link setup then the tuning is unlimited. I think most just find four link confusing and don't want to mess with it, Just my opinion.

 

I think Eric said it best "If you know what you're doing, you can make a 4-link work"...and the consensus seems to be a 140-150" car is the way to go if you run the link setup. I think there are one or two cars in the NPCA 7.0 class that are running 4-links, will try to find out. One I'm thinking of is an older Spitzer car that runs really consistent, but I saw the sister car to this one at Ohio Valley years ago with a blown Hemi that got down the track at least 25% of the time. If you're running a lot of marginal tracks, it might be the best way, but I think with a big HP motor, you might be inviting a lot of headaches. A blown 450" wedge with a glide like you're talking about might actually be a pretty good combination with a 4-link, but I don't think a 540" Hemi would be. And don't forget, when a driveshaft breaks in a door car, there's a fair amount of metal in between, in an altered you're straddling the driveshaft with your sack, not a confidence builder in my book........

 

Perhaps, some insight could be gain by talking with the Pro-Mod guys. I know they are a different aminals then an altered, but maybe they can shed some light on the finer points of hight horse power and 4-link set up's.

 

A 4-link just gives you more parts to worry about, and to fail (usually at the wrong time, or place).

 

Again, as Eric mentioned, most people DO NOT know how to adjust a 4-link! They CAN be made to work, but just because you have a 4-link isn't the answer. It has to be purpose-built, length of bars, dia of bars, size of anti-roll, etc... Invest $$ in GOOD shocks, etc..Could go on and on but Ive said my peice

 

i have thought a lot about the 4 link altereds over the years i have had several door cars with the 4-link and several altereds but to me with the altered chassis it always came down to be cheaper and a lot less adjustments and headachs if you ask me but a short wheel base altered with a ton of power say if i took the body off my car then have to worry about a 4-link something else to adjust along with clutch, timing ,fuel ,valves, pulleys to much to worry about for me and the drive shaft still not a pretty picture in my mind solid shaft are hollow tube and universal joints an inch from my sack the promods are not close to you jewels

 

Think about a front engine dragster! Your legs are over the axle housing and the boys are snuggled up to the back of the center section with a ring gear just the thickness of the housing away.

 

Four-Link Altered

Thanks guys for all the feed-back! My original plan was to go with the hard tail, but all the "why nots" associated with the four-link kept cropping up. So...thought I'd throw the question out to you guys. Thanks to you too, Will, for the great site...and to everyone else for their time. Mark.

 

Do pro mods still run swingarms so long and shocks so stiff that they're practically solid mount while being able to say that they have suspension per rules?

 

It's my understanding is that they must have a minimum rear suspension travel of 1", and it looks like they went back to the more conventional 4 link setup, 1" not alot of travel.

 

You could have 1" of physical travel and have shocks so stiff that it'll never see it?

I don't know why they don't let them just use solid mount and save their suspension money. It's not like the average fan knows or cares that they're that much unlike a factory car underneath.

 

I agree with you on that.

 

Pm

They must remove the shocks to remove the tires! With a solid mount they can't get them off!

Happy Thanksgiving to all!!!

 

We run a 4 link altered that is 129" long, supercharged on methanol. It runs 6.80's and is very annoying to the dragster guys because it rarely does anything other than go straight. We were 6th in Top dragster div2 with one semi final and one runner up. (no wins ). It tunes just like a door car in my experience. It seems to be able to go down almost any track, even when the dragsters can't. I do spend some time on scales, run about 10% heavy on the right rear and have a large anti roll bar with tripod fronts. It 60fts 1.02 to 1.05 depending on track conditions. What I believe is the key, however, is the fact that I'm running a 3.40 gear. (glide with 1.80 lo) I believe the 4 link gives me a degree of tunability as well as an ability to handle bumpy tracks that the hardtails don't have. I have been beaten by them too though.

 

PM vs Alt 4 Link

We ran both 4 link alt and a PM with yes a hard tail. The PM had a 4 link as per the rules but we ran 100 lbs springs on it with 10-90 set up on the shocks and 1 1/2 " of travel. The car woud set down on the stops as soon as you loaded the clutch. We went 6.20 with this set up. You had to stay after the tire press, and roll out. The 4 link alt was built by S&W for fast brakets. We ran a 454 3500 tight converter and a 8/71 It went 7.00 when we got it to go stright. It was to hard for us to ajust from round to round. if you change the motor it would chang the chassis (We never figure it out) Maybe somebody that is beter at chassis could but had our hands full. I joke that I went FC racing because I did not know how to work a 4 link.