IS F (2008-2014) Discussion topics related to the IS F model

ISF drop question

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Old 08-28-15, 06:52 AM
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eclipsegst
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Default ISF drop question

I have a 08 IsF and wa looking int oteh Tein springs but my car is already lower in the back since I have a custom system in the truck that has some good weight to it. Debating if I should cut the front a bit to match it up or get springs and figure something out so it's leveled. Any reccomendations.
Old 08-28-15, 07:25 AM
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streetx
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Don't cut springs. That's such a ricer move even more so when you're doing to a car that cost 60k new.

A few people have just put in the front lowering springs and left the rears stock
Old 08-28-15, 07:56 AM
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lobuxracer
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Why not? Cutting springs works just fine as long as you know what you are trying to achieve. If it's for appearance, then yeah, don't cut springs. I'd bet a lot of money if you cut 5% off the front springs you'd solve a whole lot of problems with camber curves, ride height, and spring rates. I just haven't measured the chassis to prove this yet.
Old 08-28-15, 12:33 PM
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eclipsegst
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yea ive heard of people just put the front springs on. im not sure how that would ride though
Old 08-28-15, 03:35 PM
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I8ABMR
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cutting springs , like 99.99999% of people do it , is not a good idea. Also dropping just the front of the car is not advisable in my opinion. The car is designed with a balance. Keep it that way unless you are really after just form and not function. Until I came tho this forum I have never ever heard of people lowering half the car.
Old 08-28-15, 04:04 PM
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lolfunxion
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Honestly can't believe someone with an IS-F is asking this. You bought an IS-F and can't afford lowering springs at the very least, if not coils? Cutting springs is wrong on so so so so so many levels, and just honda ricer idiot level crap.

You should definitely go back to an Eclipse. Especially if u type lyke tis.
Old 08-28-15, 04:40 PM
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eclipsegst
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Just trying to have the car even and not lower on one end. And believe me I can afford it.
Old 08-28-15, 04:49 PM
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lolfunxion
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Originally Posted by eclipsegst
Just trying to have the car even and not lower on one end. And believe me I can afford it.
Then use the search thread to find the DOZENS of threads asking this question and don't do something insanely stupid like cut springs, or even entertain it.
Old 08-28-15, 05:24 PM
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lobuxracer
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You guys are comical. There's nothing wrong with cutting springs if you know what you are doing.

The front of the IS F was raised when Lexus decided it needed more clearance for parking stops, but they didn't move the suspension mounts on the chassis, so lowering the front a little will likely fix a whole lot of issues with the camber curves, and put the car where the suspension design intended it to be. Besides, the front springs are too soft (that's why the inside rear wheel lifts when you load up the suspension while cornering) so cutting them is a perfect solution as long as you are not stupid about it.
Old 02-26-21, 04:25 PM
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Jwconeil
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I’m raising this from the dead for a legit tech conversation. I was about to buy Ohlins TTX, but decided to buy a house and build a dream garage, so I’m going to hold off on the TTX at least a season. I’m not a fan of the front wheel gap, but even more so, I want to add a little spring rate up front for tracking. The aftermarket springs aren’t great for the ISF, so I see no value in buying any.

My only options are Penske or Ohlins, not interested in cheaper suspensions. For the time being, I’ve considered trimming the front springs to add spring rate. From my research, I’ve seen that you can increase spring rate by trimming linear springs.

I see value in learning driving skills on stock suspension before going to a racing suspension. There really is no fit spring for a track oriented build, especially with how the shocks aren’t tuned to any springs but OEM.

Any real tech talk thoughts or tips? Please avoid the remarks about cut springs being rice. I’d usually agree, but am honestly curious after some research. So many on this forum just lower the front, and I’ve seen some evidence that minor trimming of the fronts can increase spring rate, level the car, give more track oriented camber, and be a strong option until someone wants to dive into a real set of race coils. I question if it’s a better option than the oem aftermarket springs that everyone ends up taking back off because they suck with our stock shocks, are too soft, and ride rough.
Old 02-26-21, 11:35 PM
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ChpEng
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I agree that it is not as absurd a suggestion as it might initially seem. The OEM front spring wire is machined and tapered flat at the top seat, but is round at the bottom with a "short coil" that fits into the lower perch. It seems one could use a cut-off wheel or band-saw to take off a certain length of the bottom wire and still make a reasonably good fit with the lower perch, although the coil pitch changes in the lowest couple of inches.


OEM front spring taken off MY11. Spring wire has flat seat at top and "short coil" at bottom.

Spring wire is high-grade steel, so it would be wise to stock up on cutting wheels or blades before starting the project.
Old 02-27-21, 06:18 AM
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McPierson
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Originally Posted by Jwconeil
I’m raising this from the dead for a legit tech conversation. I was about to buy Ohlins TTX, but decided to buy a house and build a dream garage, so I’m going to hold off on the TTX at least a season. I’m not a fan of the front wheel gap, but even more so, I want to add a little spring rate up front for tracking. The aftermarket springs aren’t great for the ISF, so I see no value in buying any.

My only options are Penske or Ohlins, not interested in cheaper suspensions. For the time being, I’ve considered trimming the front springs to add spring rate. From my research, I’ve seen that you can increase spring rate by trimming linear springs.

I see value in learning driving skills on stock suspension before going to a racing suspension. There really is no fit spring for a track oriented build, especially with how the shocks aren’t tuned to any springs but OEM.

Any real tech talk thoughts or tips? Please avoid the remarks about cut springs being rice. I’d usually agree, but am honestly curious after some research. So many on this forum just lower the front, and I’ve seen some evidence that minor trimming of the fronts can increase spring rate, level the car, give more track oriented camber, and be a strong option until someone wants to dive into a real set of race coils. I question if it’s a better option than the oem aftermarket springs that everyone ends up taking back off because they suck with our stock shocks, are too soft, and ride rough.
I've got a set of 08 and 12 springs that I used for testing: https://www.clublexus.com/forums/is-...ing-rates.html

I doubt selling would be worth messing with. If you're interested let me know and I'll send em'

With some arm twisting I could be convinced to cut an inch at a time off the lower circle and re-run the tests above.
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Old 02-27-21, 10:31 AM
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Jwconeil
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Originally Posted by McPierson
I've got a set of 08 and 12 springs that I used for testing: https://www.clublexus.com/forums/is-...ing-rates.html

I doubt selling would be worth messing with. If you're interested let me know and I'll send em'

With some arm twisting I could be convinced to cut an inch at a time off the lower circle and re-run the tests above.
I would like to work something out to do the testing. I don’t have a dyno or access to one.

It could have a four fold benefit.

Aesthetics - Our members have always been interested in a way to level the car, but the aftermarket springs generally aren’t a great option for this car.

Geometry - as mentioned above - Lance noted how Lexus increased front ride height after suspension design. This may correct some geometry errors.

Spring rate - does this really increase spring rate? If so, it’s valuable.

Cost - how many threads have we seen about this? Cheapest way to lower front of car.

Im willing to do this to try it, but I can’t collect legit data. I can only provide impressions, and that’s subjective.

Can you start with the 2012 springs since they are much more like my 2013? I think aiming for 5% of total coil length is a good start, but taking smaller portions would provide more data. Cutting in a way to make the spring actually fit the perches is important as well. Will 5% even visually change ride height?

So how can we twist your arm?
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Old 02-27-21, 11:17 AM
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I think lobux said the problem with the aftermarket springs is the current offerings just don't make a good spring. So if someone knew what to ask for and if you could convince them to, a company like hyperco could make a nice set of springs.
Old 02-27-21, 01:13 PM
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Jwconeil
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The oem shocks all changed pretty regularly between model years IIRC, so a spring that marries well to a 2008 May not work well on a 2012.


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