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HHP springs intall

5858 Views 61 Replies 8 Participants Last post by  HC5120
7
Installed the HHP springs today. I am not going tp list every step and the torque specs as those are easily found.
HHP said no realignment is necessary. I may do that in the future, but the difference in ride height is the difference of having 1, 2, 3 people in the car, or a full tank of gas versus almost empty, etc., so we'll wait and see. Car drives really good, though.

American Muscle has a good install video on it: video

And on the BMR site they have directions for installing their springs, but it's all the same. Go to this link and then click on "installation" down a little ways on the page. BMR installation instructions

There are a couple of ways to do the rear springs. In the AM video, they remove the inside A-Arm bolt and drop the A arm from there. If you do it this way, you have to drop the exhaust some to get one of the bolts out. That's pretty much how the BMR directions are, but they have you remove the caliper and also remove the bolt for the lower trailing arm.

In all it took about 3.5 hours with two of us (though my assistant helped about 70% of that time), and the total time just depends on how stubborn the suspension parts want to be coming apart and especially going back together. If doing it again, I am sure we could do the whole job in 2 hours if we were both completely focused on it, and after having done it once. Some of the rear suspension bolts were a bear to reinstall. That's typical with suspension stuff.

Here is the difference in ride height with the HHP springs for all four corners compared to the stock springs.

Front left: plus 13/16; Front right: 0
Rear left: minus 1/8; Rear right: minus 7/16

Here is a pic of the stock front springs compared with the HHP spring
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Installed:

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Rear springs side by side:
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Rear springs installed

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We used this Eastwood strut spring compressor. Worked awesome. I researched tool options quite a bit, and this seemed to be the best made. The directions say not to use an impact on it, but reading reviews online, etc., lots of people do. It worked flawlessly. Seemed very safe. $165.00 from Eastwood.
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All and all, it wasn't too bad of an install. The rear springs actually took longer because it was tough to get the bolts back in the arms and the lower shock.

The biggest worry with this install is probably compressing the springs for the front struts. I felt the Eastwood tool was very safe and solidly built and dependable.

The car drives good. I can't tell much of a difference, but I don't drive it that much just cruising around town. We will see what difference it makes at the track.

As I stated in the drag racing 101 thread I made, this isn't a necessity for 10 second cars or even high 9 second cars if they race on an excellent track with excellent prep. But it's one more thing to (hopefully) add consistency for bracket racing for me, and help me on my home track which is challenging (we'll see). I have run a 1.53 and 1.54, but my 1/8 mile 6.80 at 4400 DA in my sig was a 1.58. I think I can do quite a bit better, but we'll see in a couple of weeks. My goal is to hit high 6.60s in the fall when the good air comes back and I have fresh tires. That would be solid for a 2.85 pulley and 93 fuel at 4500 DA. I would like to go back to a 305-17 tire, too, so this might get me closer to being able to do that.

If I have something messed up that you see in the pics, thanks in advance for the heads up.
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I forgot you have 3576 was thinking 3572 so what I said about the volume is was backwards. You have way more volume than I do. I woulda try different pressures while leaving everything else constant.

You used to 60 high 1.5

You really think the springs are better???

Looks like it slowed down : (
Need a 3.70
Yes it was basically from the side. I was like, omg, it literally looked like I hardly even hit the throttle. I did mash it on the run where I rolled through after the other car took off, and it hooked pretty good, but I didn't get a time because I'd already pushed through the beams.

There's really nothing to see from the video, except that it's the laziest launch ever, lol. Pretty funny really once I saw the video. Kind of surprised it was still a 1.62. It's just completely different with these springs. I was running like 15 psi cold sometimes trying to get the car to hook. I wouldn't be surprised if I am able to run 20psi or more now.
Need a 3.70 for sure
Listen to @Unholy707

He has a bunch of 1.4 60’ time slips and tons of logged data from the track

🤣
Listen to @Unholy707

He has a bunch of 1.4 60’ time slips and tons of logged data from the track

🤣
It makes a difference with that tire he could get better than 1.4
Yeah

And his 60’ are the same as mine lol
Did you guys read what I wrote? I didn't even launch the car. The tires hooked so hard that it practically lugged the motor. I never got a proper launch in. I used to have to run 15 psi to hook and so started lower and the usual rpm I launch with didn't work, and I didn't figure that out until looking at the video, the laziest start you've ever seen, like someone was standing behind the car pushing it. I am leaving everything the same but going to work on tire pressure, though I have to raise launch to 1500. Next time out, it will be 1500 launch the whole day and adjust tire pressure.

Take a minute and read what I wrote, jeez

You guys can suck eggs, especially sick2 with his fat old wheels, ha ha
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Did you guys read what I wrote? I didn't even launch the car. The tires hooked so hard that it practically lugged the motor. I never got a proper launch in. I used to have to run 15 psi to hook and so started lower and the usual rpm I launch with didn't work, and I didn't figure that out until looking at the video, the laziest start you've ever seen, like someone was standing behind the car pushing it. I am leaving everything the same but going to work on tire pressure, though I have to raise launch to 1500. Next time out, it will be 1500 launch the whole day and adjust tire pressure.

Take a minute and read what I wrote, jeez

You guys can suck eggs, especially sick2 with his fat old wheels, ha ha
I’m not hating on you at all man! I’ll probably cut a 2.5 60’ first time out, was joking about the rear diff. But I am curious is you have the stock 1 and 3.09
I know, just having some fun. It's like this when you make a change. I was really kicking myself cause the DA was so good, and then I blew my run pushing through the beams trying to get the stall up.

I have 2.62. I would ideally like to switch back to the 305-17 on a wider wheel with no beadlock and come up with a different way to keep the tire from spinning on the wheel. That would be faster IF it hooks. I have a set of 305-18s on some bravados that I can do an AB test with, too, so I will throw those on once I figure a few other things out.

I ended up with a too big of a tire because of trying to get it to hook up more consistently, but I hope the springs will make it possible to go back to the smaller tire.
Oh wow. You just hurt unholy’s feelings hard. Too big a tire lol.

Ha. I read what ya wrote. Throw a converter in it and see what happens. 3600. Maybe 3800. Or get a tune or a pc?

How much cash will you send me w yer 2.62’s if I send you my 3.09’s?
do
I know, just having some fun. It's like this when you make a change. I was really kicking myself cause the DA was so good, and then I blew my run pushing through the beams trying to get the stall up.

I have 2.62. I would ideally like to switch back to the 305-17 on a wider wheel with no beadlock and come up with a different way to keep the tire from spinning on the wheel. That would be faster IF it hooks. I have a set of 305-18s on some bravados that I can do an AB test with, too, so I will throw those on once I figure a few other things out.

I ended up with a too big of a tire because of trying to get it to hook up more consistently, but I hope the springs will make it possible to go back to the smaller tire.
tire is not too big it’s perfect 👌
Oh wow. You just hurt unholy’s feelings hard. Too big a tire lol.

Ha. I read what ya wrote. Throw a converter in it and see what happens. 3600. Maybe 3800. Or get a tune or a pc?

How much cash will you send me w yer 2.62’s if I send you my 3.09’s?
Why are you trying to get rid of the 3.09 so bad
And it’s too big a tire for the 2.62, with the 3.09 it’s great
The right size tire is the one you can get to work. That being said, a smaller tire is lighter and faster IF you can get it to hook.

2.62 x 4.71=12.34; that's like a TH400 with a 5.00 differential. Would a 29.5" tire on a car with a TH400 and 5.00 rear gear be too much tire? With the 3.09 it would be like running a 5.87 rear gear with a TH400.

The 305-17 is also only 28" tall, so that's like effectively lowering the final/effective gear ratio, which might be better for the 1/8 mile, again all dependent on the tire actually dead hooking.

Just my two cents.
Yup

Getting 370’s for na bracket racing

I think 309 will be too low for turbo app even w 29” tire

Not dying to get rid of them. Willing to help out tho. You wanna try em?
I finally got some runs in. These were all about 5000 DA. Ran anywhere from 6.83 to 7.08, depending on traction/60 foot.

For test and tune, no prep at all, I managed a 1.62. They prepped the track some for the bracket qualifying rounds, and I ran a 1.55, 157, 159. In the last two years, I have never run two 1.5x 60' in a weekend (I've only run a few 1.5x's in the last couple years), and I ran these three all in a row, and the track was sketchy. Apparently VHT is hard to get, and so we are trying to make what we have last until the end of the season. So they only prep before qualifying, and that's it for the day. Usually they'd prep again after qualifying.

If you race on a well-prepped track, then the stock springs are probably good, imho. We see a lot of people on this site throwing on a tire and hooking up pretty darn well. Just depends on the track, and how important consistency is to you.

I do have a suspension controller installed, and I will swap that back out for the stock one some time while at the track and do a back to back test, eventually.

I got third place out of about 25 or so cars in the pro class Saturday, and made it several rounds today, Sunday. Two weekends of bracket racing left.

Overall, I am happy with the HHP springs. The car rides just the same as it did before, and it's more consistent at the track, though testing has been tough due to minimal prep.

Ran 15 psi cold all weekend. Still ran 104.67 MPH on a run, so the low tire pressure didn't impact that.
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If you race on a well-prepped track, then the stock springs are probably good, imho. Overall, I am happy with the HHP springs. The car rides just the same as it did before, and it's more consistent at the track, though testing has been tough due to minimal prep.
Congrats on going rounds. Hell yeah : )

I think it’s bigger than a supply problem. Something up with the formula. The glue ain’t what it used to be
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Yup

Getting 370’s for na bracket racing

I think 309 will be too low for turbo app even w 29” tire

Not dying to get rid of them. Willing to help out tho. You wanna try em?
Did you ever install that 3.70?
Yeah. Gonna see what it does Thursday
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