irish44j

iTrader: (38)

Here's the deal:
As of right now I'm a little sketched about the car's handling.
car has about 50K miles.
I have:
Stillen RSB and BlehmCo LTB with stock SE suspension. When I put the LTB on as you recall I noticed that the tail of the car seemed to "lag" during quick lane changes but wasn't that bad. But the other day I put on all new tires (same Falken 512's I had before) and with the freash tread this "lag" is FAR more apparent, almost to the point where it's a bit (scary) to make a quick lane change at high speeds or a zigzag turn....it's like the back end of the car is really "loose" and takes a second or two to recover and follow the front of the car....It's really a bit discomforting to tell the truth. Almost like the stock setup without a RSB but worse.....

So my question(s)
1. obviously the tires are a directional tread - could this have something to do with it (though I didn't notice this problem the last time I bought the same tires new)

2. you guys think it is a spring/strut issue or maybe just the subframe/frame flexing slower than the steering responds?

3. suggestions (reposition RSB, SFC's, ???)

4. Am I just imagining it since I'm used to having a softer front end w/out the LTB and a stiff tail with the RSB?

I really don't want to drop the car if I can avoid it, especially with winter around the corner and snow and all that....I know theres one of the local guys (Dulles area) that has the RSB, LTB, and SFC's all on there - do you have this feeling?

I dunno, just doesn't feel "right" and I know the struts are still fine because the ride over rough roads is actually very good (better than before the LTB install)...

Matt93SE or anyone else - any suggestions?

thanks,
J

vsamoylov

ltb? where did you get one of those from? custom?

irish44j

iTrader: (38)

www.mattblehm.com (Matt93SE makes em)

BlackBIRDVQ

iTrader: (15)

I belive your rear struts or strut mounts are blown. I would highly recomend repleacing em with something like KYB GR2 if you are going to keep the stock suspension, or if U want a little bit of adjustability add some AGXs in the back. I found out that lowering my GXE pretty low in the front and only .5" in the back I get plenty of oversteer. I bumped the car down lower to 1" in the back and the car basically starts to drift in a very fast tug of the steering wheel. I have yet to understeer with my low front end and good Azenis Sport 245s on 17" RPO1s... here is a *** end shot of the car.

spirilis

iTrader: (2)

Irish was thinking of the Illuminas anyway I think (HIGHLY recommend... very nice ride quality)

irish44j- Ever thought about removing the RSB for comparison?
For that matter, does the car feel more likely to understeer or oversteer? ("lag" seems to give me the idea that you're dealing with chassis twist, which SFCs would help with...)

irish44j

iTrader: (38)

yeah I'm really leaning toward SFCs....I don't think the struts are bad since the handling and tail responsiveness was great before the LTB and tires....I mean seriously this just happened with the LTB install. Chassis twist "seems" to me like what it most feels like....but this car has a much bigger "a s s " than other cars of mine inthe past (Integra, accord coupe, triumph), not to mention our non-independent suspension in the rear (why????)

Yeah I'm thinking of Illuminas...but $$ is a little tight right now so I'll probably wait until spring, since I really don't think the struts are bad.

So...experiences on SFCs? which and where to buy? (and how much to install - since I assume you have to have them welded?)

irish44j

iTrader: (38)

experiences by others who have the LTB installed?

spirilis

iTrader: (2)

That's cool (re: the struts)... I was gonna let mine go too until I started noticing the ride quality go downhill fast (minor potholes/bumps felt a lot harder than before). They're worth the wait though, trust me. Especially if you add other suspension mods to the mix (LTB, SFCs, RSB, etc.)

To the best of my knowledge, the only vendor that makes Subframe Connectors is Warpspeed Performance. Here's their site for the 5th gen SFCs:
http://www.warpspeedperformance.com/sfcgen5/sfcgen5.htm

WSP makes 3 stages of SFCs. Stage 1 is two long cold-rolled steel bars that go along the sides, and have 3 pads each that are welded to the underbody. Note that it is IMPERATIVE that the installer perform this installation with the suspension in its normal resting position (i.e. jacked up on a 4-post lift, liftable ramps, etc--can't lift it by the chassis)
Stage 2 is cross-bracing, where a center "plate" is suspended by 2 metal beams from the center pads of the stage 1 SFCs, and all the other corner pads have diagonal metal beams going to the corners of this plate.
Stage 3 is just 2 more crossbeams between the front and rear pads (the center pads are already linked via the stage 2 SFCs). Stage 2 and 3 are bolted up, and according to WSP's install instructions (http://www.warpspeedperformance.com/...pplication.htm), require drilling into the stage 1's welded pads.

I wanna do stage 1 only sometime soon. The reason being is that stage 2 and stage 3 have fitment issues... I believe one member "Dave B" (not DAVEB the parts guy) has a 4th gen with stage 1+2 SFCs, and he said he had to take a sledgehammer to one of the diagonal cross-beams to make it clear the exhaust pipe without banging a lot. WSP's site seems to imply that there are no fitment issues if you use WSP exhaust components, and they have some replacement exhaust pipe piece for fed-spec 2000 Maximas (and some cali-spec; depends on whether you have an S-shaped pipe connecting your cat to the B-pipe) to make it clear for stage 2.
Stage 1 is supposed to make the most difference, followed lesser by stage 2, and even lesser by stage 3. A stage 1+2+3 setup is more for serious autocrossing.

As for ride quality... I'm not sure how a stiffer chassis affects ride quality. It obviously improves handling by making the suspension's operation more predictable, since you don't have chassis flex altering your alignment on-the-fly (same idea as the FSTB/LTB, I think?). When I think of a "stiff" chassis I think of my coworkers' BMW, Audi... etc. I've heard (from Dave B) that a stiff chassis is more or less a main part of the design of european cars' suspensions... with a stiff chassis they can run softer springs, and harder struts to produce good handling with good ride quality too.

Since you installed a stage 2 LTB, I think it's suffice to say you've done just this, but only on the front-end of your car. While having the majority of the chassis stiff but the front and rear soft might still handle/feel okay, having the front and rear stiff but the center chassis not as stiff would produce what I'd imagine to be "unpredictable" results.... after all, the front and rear portions of the suspension were designed with the flimsy chassis in mind, so stiffening them up is breaking the assumptions. SFCs might complete the layout and provide a balanced stiffness (huhhuhhuh, I said stiffness).

Your options going forward seem to be-
1. Lower the car (involves swapping springs, and if you wanna do it RIGHT, you'd wanna buy those Illuminas too... but since $$ is tight you wanna wait on that)
2. Try out SFCs... not sure how much installation's gonna cost, but stage 1 alone is $150 per WSP's site, add less than $37 for shipping (going by their figures on that site), and everyone I've heard who's installed SFCs have been thoroughly pleased with them. Sounds like the safer bet to me.

Just be DAMN sure that the installer knows what he's doing... if they weld SFCs up to the subframe with the suspension resting in a non-normal position (from lifting it by the chassis instead of the tires/steering knuckle/rear beam/whatever), your chassis will be stuck in a permanently abnormal position (results in not being able to open/close doors properly, camber permanently off, etc. Note that if this happens, they can un-weld the SFCs and the chassis should return to normal... but it's best not to deal with that.)

Alright, enough for this post. I wish I could write this quickly and fluently at work

irish44j

iTrader: (38)

wow that was one of the more complete and informative responses I've ever seen on the org! Will definitely take it under consideration....dammit I knew I should have never touched this car with the first mod....the madness never stops!!!!! haha

spirilis

iTrader: (2)

Hahaha yup

I wanna do Stage 1 SFCs first if possible... my only issue is that I gotta go talk to all the local shops and find one that's done SFCs before, 'cause I wanna find somebody who's done these before so I know they'll do it right. That means I need to spend time on the weekends/whatever finding and talking to all these shops

Then FSTB + LTB should round it out. Maybe an RSB if I'm still not satisfied... but with the Illuminas I have some room for adjustment. Extra front-end traction will be welcomed very much though.

irish44j

iTrader: (38)

You don't have a RSB yet?!?!?! Man, get that...it made a huge difference all by itself...

let me know which shop you do it at...you're not that far from me...Also, VMaximus02 is here in NoVa and has ALL of the suspension goods - SFC, RSB, FSTB, etc. (soon to install LTB also) so hopefully one fo thes days I'll get a ride-along in his car!

irish44j

iTrader: (38)

btw spirilis, you going to the Sandy Pt. meet this weekend...not TOO far for you!

Matt93SE

iTrader: (44)

If you're still on the factory struts, that's the first thing you should look at to change.

The stock struts are fine for daily driving and reasonable cornering, but when you start taking the car close to its limits (and you are if you notice problems like these), then the struts aren't up to the job anymore. You need something stiffer. I would also highly suggest some stiffer springs, but you have to lower the car for that (unless you go with coilovers and keep them raised completely up)

I would also HIGHLY suggest Warpspeed's SFCs.. I was the first one to drive my 3rd gen and their 4th gen after installing them.. (they did their 4th gen prototype set on their car first, then tossed me the keys to test drive it while they were doing them on my car)... Anyway, there was a HUGE improvement in handling and road feel. no more of the chassis bouncing and fumbling over potholes.. it was just a "WHAM!" and the hole was gone. much flatter in the corners as well. the back end stays planted and the front end doesn't nosedive into the corners from the body leaning into the corner. I can also jack up my car on opposite ends and rock the car back and forth on jackstands.

If you're serious about auto Xing though, I only suggest going with the stage I. installing the stage 2 or 3 SFCs will throw you into a prepared or modified class in a heartbeat. (as will my stage II lower tie bar. the stage I is considered the same as a FSTB, so they're allowed in the ST classes... but following the rules to the letter, you're only allowed to add braces to two mounting points per brace- one on each side. thus my Stage II bar wouldn't be legal for ST classes). now are they going to say anything? probably not, unless you're in contention for a regional title or are heading to Nationals.

...................... I digress......

things to look at:
1. get new struts. you need 'em. 50k on the stock struts is more than enough to wear them out, especially if you drive hard. plus they're just not up to the job if you do drive hard.
2. check your tire pressures. should be close to even in both front and rear. 30psi is a good round number.. if you have low pressure in the tires, they can do some weird stuff. (I nearly spun at TWS at granny speed because the valve stem seal was messed up in my car and I was down to 15psi in a rear tire)
3. stiffer springs.... get some. you'll thank me later.
4. subframe connectors.. see #3.


Yeah, the mod bug has bitten... all you can do is feed the monster now!

irish44j

iTrader: (38)

thanks matt....all as I expected, unfortunately....I had an outside hope someone would say "crank the back tires up to 35 psi and all will be perfect" but of course that's wishful thinking.

well, I guess Illuminas and "maybe" maxspeeds coming soon (dammit) though losing ground clearance really worries me as much time as I spend driving snowy mountain roads inthe winter......and the LTB already lost some of i!

SFC will be my last effort since I can't install them myself.....

as to auto-x...if I ever do it with the max it'll just be for fun so if I have to go up a class and get whooped so be it...

I have my triumph for the fun auto-x!

Triple8Sol

iTrader: (29)

Matt93SE: Maybe you should develop your own version of a Stage 1 SFC? I wonder if you would be able to possibly make a better design and/or cheaper? Either way, it would save us from having to deal with WSP haha...

Matt93SE

iTrader: (44)

Exactly.... I do Auto X for the fun experience and seat time... I'm nowhere near a nationals contender, so I don't care what class I'm in (I run SM now, so there's really nowhere to go!) I'd rather spend the time at the roadcourse going 100+ around a corner instead of 25... we've got an awesome road course just an hour and a half away... http://www.mattblehm.com/movies/tws_1.wmv

Anyway, you can try jacking with your air pressure some and see what happens, but I don't think you'll have the dramatic effects you were hoping for.

E55AMG2

iTrader: (4)

Irish, you should also check that your rear tires arent overinflated in addition to worn rear struts and the LTB mod. The fact that they are 4-5 pounds too high will introduce too much unwanted bumpsteer into the rear suspension. I had this problem for some time before discovering its cause.

Matt93SE

iTrader: (44)

I kinda can't.. :\

I was the one that prototyped the 3rd gen SFCs on my car, and I signed a non-compete type of agreement with them in exchange for the discounted proto parts on my car.
that's why I haven't touched them, or the exhaust stuff-- since I prototyped and dyno tested their 3rd gen y pipes as well..

Ya win some, ya lose some.. I'd rather not burn my bridges between myself and Dallas, since we have a pretty good relationship going.. (he actually takes and returns my phone calls! )



E55... Since you're obviously watching this thread.... I sent you an email yesterday or so reguarding the LTB.. are you still interested?

E55AMG2

iTrader: (4)

Matt, I got the email. I need to look into combining your LTB with WSP's SFC, which will be my next mod. If you know about the fitments on a 5.5 gen (or can ask dallas for me) I might just have to get one of those.

scopium

irish44j.. here is my theory and suggestion

the reason why we put rsb is stiffen the back of the car and get rid of the imbalance .. since the fron is already "stiff" enough

by putting the rsb we kinda balance things out..

but however.. after you got tha LTB.. you reenforced the front which again caused an imbalance and made back of the car drag a bit..

now this is what i suggest.. if u dont want to lower your car.. but want to stiffen up the suspension a but

stick with your stock springs.. but get Tockico Blues or kyb gr2.. this will stiffen the suspension a bit more and get help rid of the imbalance...

hope i was of some help.. and i make sense

MaxArt

Irish - Just a quick observation, but I think Matt is really on to something with the point about tire pressures. I'm just running a FSTB and RSB on the Max right now which has improved the handling and feel incredibly. But I've never had a car that is so sensitive to tire pressures. My GSR has been modded a little (bigger bars and urethane bushings) and I can move the front and rear pressures up and down relatively and there is little change to the handling dynamics, so I just go for the best ride/handling compromise. But on the Max - too high in the front and there is little on center feel - too low in the back and it understeers and then when the sidewalls finally shift, it jumps. I'm running 34 frt and 32 rear right now and feel like there is a reasonable balance and trade off. I don't think we think about the width of our rims and tires enough either. Wider tires on narrow rims give more of a C to the side wall (more flex and roll), while a wider rim will straighten the sidewall up giving a stiffer ride and less roll. A lot of guys go to a wider/lower tire to get a wider patch on the ground, but end up with a different handling dynamic. Us old dirt and small track guys know that every gain usually comes at a trade off cost. That's why we often ended up with four different tire and wheel sizes.

SoonerFan

iTrader: (5)

i didnt feel like reading all those long @ss responces but im thinking it is bad struts. will discuss more with you in person

kirzan

iTrader: (1)

I'm not sure exactly what you mean by 'the back end lags.' You're talking about a long wheelbase car with a beam axle. It's desiged to provide some passive rear-steer, but I don' think that's what you're referring to. You have a long wheelbase car with shall I say, less than optimal suspension design.

Generally speaking, struts (unless they're seriously blown) don't have a big impact on handling performance. Springs are the main culprit. 5th gens tend to understeer to a point then are susceptible to snap oversteer, courtesy of the multi-link beam rear axle.

I doubt your tires are the problem. You're just noticing it more since you've got more grip all the way around. I was really unhappy with the RSB, since it seemed to make the car even more tail happy. Kinda reminded me of driving my Dad's old Porsche 911.

Sounds like you have some chassis flex, but your mods should be taking care of that. Are you on a stock spring/strut setup? You might wanna consider some stiffer springs and shocks to go with them. I pretty much eliminated the snap-oversteer with Maxspeed/GR-2 combos and an FSTB. I'm considering the subframe connectors in the front, but that might destabilize the rear.

The beam axle rocks for smooth roads, but sux ***** for mid-corner bumps ... as I'm sure you know.

spirilis

iTrader: (2)

The subframe connectors go the length of the vehicle, they're not really "for the front" vs. "for the rear" btw

irish44j

iTrader: (38)

Yeah, but I thought with just the RSB it was very well balanced and really liked the handling - did not feel it was tail-happy at all....I put on the LTB hoping to flatten out the front end and make it steer more solidly (which it did).....

again, the struts felt FINE last week....I noticed a little bit of "tail lag" when I first put on the LTB but not much (I had 225/50/17 Falken 512's with about 20k miles on them at the time). Now that I put on the new 512's (235/45/17) I really notice it alot...so I'm thinking that it has alot to do with the fresh tread and the slightly smaller sidewall/wider tread....

I am running the tires at 34 front 31 rear as I used to...I added about 2-3 lbs to the backs on the way home today which possibly improved it a little-but hard to tell since I didn't get back on the highway....

I guess I'll just drive a little more gingerly until I can get new struts/springs/SFCs on there....

what I really need to do is drive a stock max again, and then my car will probably feel GREAT to me

Matt93SE

iTrader: (44)

Yup.
I drove a stock 3rd gen a few weeks ago and thought I was in a Cadillac!

VMaximus02

iTrader: (1)

Hey Matt,
Thanks for the email! The 5th gen rear mounting points were different than the instruction on your webpage (for 4th gen Maxima). Good news, I finally got the LTB installed. It was a big challenge and very time consuming since I have the automatic transmission. The mechanic had to jacked up the auto-trans to able to get the socket onto the driver side control arm bolt! There was no possible way to tighten the bolt with the car on the ground. However, he did tighten the passenger side bolt with the car off the lift. I just hope that there won't be any issue later with the rubber bushing on the driver side!

As for fitment, it sure was a VERY tight fit. The clearance between the bar and the Cattman's y-pipe was atleast 1" or more. Since my car was lower with the aftermarket springs, I am a little concern. Anyhow, I do suggest that you should consider designing the cups diameter a little bigger for ease of mounting the socket onto the bolts. I also think that you should half cut the cup at the driver side control arm bolt so that you can get a regular wrench to fit into. This revision will definately ease the installation and time for the auto-trans car.

As for performance, the change was noticeable especially with the steering. The car felt lighter and more sensitive to the steering wheel input. I think it was because the car is now more NIMBLE from the LTB's bracing. I did a few emergency manuvers. The transition of the car was much more "hyper" sensitive as if power steering has increased in boost. Though, I never felt lost in control since the car always retained its composure. This could be because I had other bracings and structural stiffenings on my car. Therefore, the sudden change in steering did not upset the chasis much. I will adjust the front tire pressure tomorrow and see if that lessen the steering reaction.

I need a few more days to further evaluate this new suspension mod. My impression so far is very positive! I will update my evaluation later.

vsamoylov

so you guys suggest not getting it ?

E55AMG2

iTrader: (4)

Well here is the thing. I know this now after testing it extensively last nite. The RSB improves the handling (giving it a more neutral character). However:

If your rear tire pressures are too low:

expect the rear to lag severely, then snap over

"" "" to high:

Expect the rear end of the car do step out under braking, and/or hop and skid under severe cornering.

Should you get it just right, then the car should rotate gradually as you brake towards the apex of the corner. When changing lanes, the car should feel planted.

NOW, here comes the tricky part. What is the correct rear pressure??? That, my friends, is totally tire dependent. Some tires will be higher/lower than others. The best thing to do, find a large open space and test different pressures until you are satisfied.

Please dont hesitate to IM or PM me for a better explanation.

PS: if your rear struts are worn, everything that I talked of earlier will be more exaggerated.

irish44j

iTrader: (38)

E55, we're talking about the LTB but it seems like you're talking about RSB....

I had no troubles at all with just the RSB....car felt great except for a little bit of front-end dive into hard corners...

E55AMG2

iTrader: (4)

IIRC i thought you said the car had a nasty snap oversteer from the RSB, thats why u installed the LTB in the first place. Or did I read it wrong? I think that you might have to remove it to regain your neutral handling.

Also, I know you were talking about the LTB, but after a bit more research and testing, I think it may actually reverse what the RSB does. Not at all knocking the prodcut or Matt, but its just not for me i guess.

vsamoylov

i really dont see the point of sfc and ltb. i can see the point of the rsb. that is how far i would go and then add rsb and frsb also. but no ltb and sfc.

spirilis

iTrader: (2)

SFCs and LTB? Raises the limits of the suspension... keeps the alignment from dynamically changing on-the-fly from chassis flex. I guess that's the best way to describe it.
(stable alignment == better traction)

spirilis

iTrader: (2)

BTW, if you think the FSTB is worth anything, then consider the LTB is like the FSTB on massive steroids, and SFCs might not be as obvious... but the SFCs sorta do the same thing that the FSTB does, except long-ways across the whole vehicle.

vsamoylov

ok i get what they are for now but if they are supposed to do that, how come people are having probmles with them? make it seems like they dont do their job and ruin the other suspension mods.

spirilis

iTrader: (2)

What problems?

Fitment issues? That has nothing to do with how they do or do not do their job...

Handling issues? irish44j's the only person I know who has handling issues with the LTB right now, and he doesn't have SFCs.

irish44j

iTrader: (38)

I wouldn't call them handling "issues"...I'm just trying to tweak things out so they're "perfect". I mean, with RSB and LTB and FSTB the car handles great overall, I'm just trying to correct a specific bad feeling I get in certain (rare) maneuvers....

I could easily take the LTB off, but why? I know the LTB is doing what it's supposed to - now I have the front and back of the car stiff, I just need to get the middle of the car stiff (with the SFC's)....

Fitament of the LTB is perfect once you figure out how to install it right. Just like any car suspension/brake/engine mods - some are harder to install than others. This one I had trouble with but eventually got it right. Now that it's no, fitament is dead-on....

VMaximus02

iTrader: (1)

Update:

I have driven the car for several days. Somehow, the variable assisted power steering has adjusted to the new stiffness of the LTB's and now provides much better steering effort. The car's frame is so rigid now that the ride has improved noticeably. I feel like I can change to a stiffer springs/struts without upseting the chasis. However, I won't do that. My next and hopefully last mod will be a lighter/wider track wheels. The only negative affect of upgrading to the bigger wheels is the wide turning radius.

As for my opinion, I definately recommend the LTB to everyone here. I think those who consider getting the LTB should also look at getting the stage one SFC's from Warspeedperformance. The LTB will stiffen the front end of the car. The subframe will strengthen the mid-section of the car. And the RSB will tighten the rear section of the suspension. With the rigid chasis, you can get stiffer springs/shocks to further enhance the handling performance without downgrading the ride characteristic of the car.

Beware: Those who have auto-transmission. The installation will be a challenge with the LTB's.

irish44j

iTrader: (38)

Vmax,
by the way, did you get your SFC's installed around the NoVa area? If so, where? I'm about to order the stage 1 SFC and would be interested in finding a good shop to put it on (and how much $$ to do it?).

josh

E55AMG2

iTrader: (4)

do the stage 2 as well. from what I have read, that is the way to go...