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Factory Boss struts and shocks question.

Rebound only. The 18000C dampers adjust the compression and rebound as do the Koni Sports. But you cannot adjust them independently.
 
Again, thanks. I knew what you were saying the first time.

I'm a member of the K.I.S.S. club. The more adjustable variables I have, the more trouble I get into.

Just one more question, and I know it's all opinion. Out of the two, Koni yellow or 18000-C, which is a better strut/shock?? I lean toward the Koni.
 
I have not used the Koni's but they have an excellent reputation. The 18000 C's are Tokico D-Spec's made to Multimatic's, Ford's contract race and development team, dampening specs. I suspect both have similar dampening characteristics. One advantage of the Koni's is that if one damper fails and it's your fault you can get a single replacement and that will be more challenging with the 18000 C's.
 
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NFSBOSS said:
Rebound only. The 18000C dampers adjust the compression and rebound as do the Koni Sports. But you cannot adjust them independently.

Wait!!! Is there something to the factory Boss struts that I don't know about?
They are just Tokico Illuminas valved to Ford specifications--Illuminas are single adjustable, and each adjustment moves both rebound and compression. See shock dyno:

tokicorear.gif

Now as for a matter of shock quality and performance, I'd actually pick yellows over the 1800c's. The D specs are notorious for poor performance, and if you find a shock dyno, they look pretty suspect. However, I didn't know they were valued to Multimatic's specs--that's a company which I have huge respect for. They're local to me and do tuning for major race teams, and even have a 7 post shock rig in house.
 
boro92 said:
Wait!!! Is there something to the factory Boss struts that I don't know about?
They are just Tokico Illuminas valved to Ford specifications--Illuminas are single adjustable, and each adjustment moves both rebound and compression. See shock dyno:

tokicorear.gif

Now as for a matter of shock quality and performance, I'd actually pick yellows over the 1800c's. The D specs are notorious for poor performance, and if you find a shock dyno, they look pretty suspect. However, I didn't know they were valued to Multimatic's specs--that's a company which I have huge respect for. They're local to me and do tuning for major race teams, and even have a 7 post shock rig in house.

You are correct when the Boss first came out Ford explained how the shock adjustment effected the compression and rebound. The Boss 302 and the LS model use different spring rates and shock tunes.
 
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2012Boss302 said:
Pardon the ignorance, how do you read this chart. I layman's terms what does it mean???

It means Tokico Illuminas suck :D

The top is bump, the bottom is rebound. Your rebound should always be greater than bump, but clearly this isn't the case with the Illuminas for that specific application (integra I believe).

Going from left to right is the speed ie) how quickly the shock responded to the force.
The smaller #s is low speed response, the higher numbers are high speed response. Low speed response is going to be most relevant for track use (as it determines transient response).

Each line is each adjustment...so 1 adjustment should have 2 lines - one for bump and one for rebound.
You can see in the dyno that the bump response becomes digressive, but the rebound does not. Hence why Tokico's ride harsh.

You can also see that only the first 2 adjustments (1 and 2 on the knobs - softer settings) have more proper bump/rebound ratios--where rebound is greater than bump. Anything above the 2nd adjustment greatly increases bump without moving rebound in the same relative manner. Sooo although our 5 way adjustable shocks adjust both bump and rebound, we can consider it to only move bump given this graph (because the differences in rebound are minimal).

I cant help but wonder what the shock dynos look like for the Boss specific Illuminas--because Ford specified the valving on the ones we have. Hopefully it's not as bad :)

EDIT: after seeing this, I'm totally dialing back my shocks down to the stock #2 settings.
If anyone is after more rear end bite mid/exit corner, increase the rear shock setting. Bump stiffens greatly but rebound does not...so it'll keep that rearward weight transfer for longer--prolonging rear grip.
 

Domestic Product

Big fat tires and everything !
boro92 said:
It means Tokico Illuminas suck :D

The top is bump, the bottom is rebound. Your rebound should always be greater than bump, but clearly this isn't the case with the Illuminas for that specific application (integra I believe).

Going from left to right is the speed ie) how quickly the shock responded to the force.
The smaller #s is low speed response, the higher numbers are high speed response. Low speed response is going to be most relevant for track use (as it determines transient response).

Each line is each adjustment...so 1 adjustment should have 2 lines - one for bump and one for rebound.
You can see in the dyno that the bump response becomes digressive, but the rebound does not. Hence why Tokico's ride harsh.

You can also see that only the first 2 adjustments (1 and 2 on the knobs - softer settings) have more proper bump/rebound ratios--where rebound is greater than bump. Anything above the 2nd adjustment greatly increases bump without moving rebound in the same relative manner. Sooo although our 5 way adjustable shocks adjust both bump and rebound, we can consider it to only move bump given this graph (because the differences in rebound are minimal).

I cant help but wonder what the shock dynos look like for the Boss specific Illuminas--because Ford specified the valving on the ones we have. Hopefully it's not as bad :)

EDIT: after seeing this, I'm totally dialing back my shocks down to the stock #2 settings.
If anyone is after more rear end bite mid/exit corner, increase the rear shock setting. Bump stiffens greatly but rebound does not...so it'll keep that rearward weight transfer for longer--prolonging rear grip.

I agree they suck, having had the Boss out at speed at HPDEs in the advanced group in stock form. The car is totally under dampened and sprung IMO. The car needs better dampers and springs as well as some adjustable camber up front. I messed with the stock dampers and did not notice any change in performance, had better results changing tire pressure. So as with any car that you take to the race track some modifications are in order. Ditch the stock dampers and springs and up grade. For the street the car is perfect, other then it could sit lower.
 

unrealford

Mustang owner since 84
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0
Re: Re: Factory Boss struts and shocks question.

Domestic Product said:
I agree they suck, having had the Boss out at speed at HPDEs in the advanced group in stock form. The car is totally under dampened and sprung IMO. The car needs better dampers and springs as well as some adjustable camber up front. I messed with the stock dampers and did not notice any change in performance, had better results changing tire pressure. So as with any car that you take to the race track some modifications are in order. Ditch the stock dampers and springs and up grade. For the street the car is perfect, other then it could sit lower.
Agree, but in stock form, look how the Boss compares with other cars around the TopGear track, not too shabby.
Of course there's room for improvement, but driveability changes, either you find a middle of the road( Stock Boss). Or go for full competition and you have loss the Boss as a Daily Driver quality. And I'd say 70% of Boss purchases will never see track use.
Look at this video and look at the track time compared with cars like the V12 Vantage. You gotta admit even for stock it performs pretty well and even looks more balanced compared with a Roush Stage 3

https://www.youtube.com/watch?feature=player_detailpage&v=b2kD74KKLYM
 

Domestic Product

Big fat tires and everything !
Re: Re: Factory Boss struts and shocks question.

unrealford said:
Agree, but in stock form, look how the Boss compares with other cars around the TopGear track, not too shabby.
Of course there's room for improvement, but driveability changes, either you find a middle of the road( Stock Boss). Or go for full competition and you have loss the Boss as a Daily Driver quality. And I'd say 70% of Boss purchases will never see track use.
Look at this video and look at the track time compared with cars like the V12 Vantage. You gotta admit even for stock it performs pretty well and even looks more balanced compared with a Roush Stage 3

https://www.youtube.com/watch?feature=player_detailpage&v=b2kD74KKLYM

Yes , I agree the Boss is awesome for a off the floor factory American car the GT is as well! That's why I (we ) have them. I do not mean to dis on Ford or the Boss. The car is fun to drive in stock form and held its own and then some on track. I could be happy and just drive the Boss as is. But I always mod my cars.
Every one has different needs and wants for their cars. My goal for my Boss is to not make it into a track car but just make some improvements here and there. Fix some stuff that IMO Ford should of done with the car.
Anyways to answer the first post, I did not notice any difference in playing with the adjustments on the stock Boss shocks. That's just me. For those that want to leave well enough alone they do the job and the ride is great on the street and they will do the track. I think I would leave them at 2 and just drive the car.
Nice video yes the Boss in stock form will humble much more expensive cars!
 
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boro92 said:
It means Tokico Illuminas suck :D

The top is bump, the bottom is rebound. Your rebound should always be greater than bump, but clearly this isn't the case with the Illuminas for that specific application (integra I believe).

Going from left to right is the speed ie) how quickly the shock responded to the force.
The smaller #s is low speed response, the higher numbers are high speed response. Low speed response is going to be most relevant for track use (as it determines transient response).

Each line is each adjustment...so 1 adjustment should have 2 lines - one for bump and one for rebound.
You can see in the dyno that the bump response becomes digressive, but the rebound does not. Hence why Tokico's ride harsh.

You can also see that only the first 2 adjustments (1 and 2 on the knobs - softer settings) have more proper bump/rebound ratios--where rebound is greater than bump. Anything above the 2nd adjustment greatly increases bump without moving rebound in the same relative manner. Sooo although our 5 way adjustable shocks adjust both bump and rebound, we can consider it to only move bump given this graph (because the differences in rebound are minimal).

I cant help but wonder what the shock dynos look like for the Boss specific Illuminas--because Ford specified the valving on the ones we have. Hopefully it's not as bad :)

EDIT: after seeing this, I'm totally dialing back my shocks down to the stock #2 settings.
If anyone is after more rear end bite mid/exit corner, increase the rear shock setting. Bump stiffens greatly but rebound does not...so it'll keep that rearward weight transfer for longer--prolonging rear grip.

Whoa! Correction!
I'm wrong. I looked at the numbers on the Y axis only just now. Rebound is the top of the graph, bump is at the bottom.
Rebound should always be positive numbers. So the Illuminas on our cars adjust mainly rebound--a good thing.
A higher setting = more rebound, with little affect on bump. In the dyno posted (for Integra), this application actually shows that the bump/rebound ratio curves to be unideal anything 2 and below. So according to this, you want to run at least a 3 (where rebound becomes higher than bump)...otherwise the wheel will jack down over a series of bumps (because the shock is not pushing back out quick enough).

You can run a softer rear for more rear grip on corner exit. A stiffer front would do a similar thing -- forcing the shock to extend quicker--therefore transfering weight rearward for increased mechanical grip out back.
 

Grant 302

basic and well known psychic
boro92 said:
Whoa! Correction!
I'm wrong. I looked at the numbers on the Y axis only just now. Rebound is the top of the graph, bump is at the bottom.
Rebound should always be positive numbers. So the Illuminas on our cars adjust mainly rebound--a good thing.
A higher setting = more rebound, with little affect on bump. In the dyno posted (for Integra), this application actually shows that the bump/rebound ratio curves to be unideal anything 2 and below. So according to this, you want to run at least a 3 (where rebound becomes higher than bump)...otherwise the wheel will jack down over a series of bumps (because the shock is not pushing back out quick enough).

You can run a softer rear for more rear grip on corner exit. A stiffer front would do a similar thing -- forcing the shock to extend quicker--therefore transfering weight rearward for increased mechanical grip out back.

Are you *sure* this time? ::) :p
 
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Grant 302 said:
Are you *sure* this time? ::) :p

Hah! Yes Grant, I am.
I'm used to looking at charts with it oriented the other way around...sorry :D
A positive number is the shock extending back -- that is rebound. A negative number is resistance to compression (bump). So the chart shown has rebound up top and bump on the bottom :)
 

Grant 302

basic and well known psychic
boro92 said:
Hah! Yes Grant, I am.
I'm used to looking at charts with it oriented the other way around...sorry :D
A positive number is the shock extending back -- that is rebound. A negative number is resistance to compression (bump). So the chart shown has rebound up top and bump on the bottom :)

:) Just giving you a hard time. I was pretty sure you were reading it backwards...but I didn't see the point in discussing the properties of the Integra graph. Still could be night and day from our cars. I've handled the LS and Street Boss shocks/struts side by side and the compression differences can be felt even by hand.
 
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Grant 302 said:
:) Just giving you a hard time. I was pretty sure you were reading it backwards...but I didn't see the point in discussing the properties of the Integra graph. Still could be night and day from our cars. I've handled the LS and Street Boss shocks/struts side by side and the compression differences can be felt even by hand.

Agreed to the Integra point. I really wish there were shock dyno information on the factory struts as well as the M18000C struts (or D or whatever--I forget the p/n). I'm really not a fan of Tokico struts after running illuminas twice on 2 different applications, but the FRPP items are developed by Multimatic...so it can't be half bad!
 

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