J.

I drove one the 7th gen celica's in stock trim that car was a great car, but it never was in the same class as the type "R", but it was in the class with other Honda's. The front suspention was not the problem but the rear was, because under breaking the car would change rear toe making the car hard to drive on stock shocks. The thing that made that car so good was the torque and how light the car was. It also had a 15x6.5 wheels so you could use the 15" tires that were avalible at that time. Its funny you ask this question because the celica did well in stock trim, but in STS it did not do as well as the '89 civic's and I do think after driving the two cars that the double wishbone makes a difference in that class. The stock Honda springs are too soft as a hole, and the weight of the Honda hurts the car. (The Honda's that were in G-stock at the time did not have a good wheel size.)

There are other classes that have this battle like the MR2 and the Miata's in E-stock. Both cars are very good and one has double wishbone and the other does not, and the Miata weights about 350lbs less. It just shows that its not all about what you have as a suspention but you have to look at engine torque curves, wheel sizes and what tires are avalible. I don't know if this helps or not just my two cents.

Robert

 

Geez... books have been written on the subject...

I supose I meet your mid '90s quailification as I have been autocrossing since the early '80s, have been going to nationals since '89, am a student of suspension design and developement and served on SCCA's Solo Events Board.

First, you must understand that a car's success in autocrossing is more dependant on favorable classing and the efforts of capable drivers than its particular suspesion design. The 6th gen Celica dominated with the efforts of tallented drivers until it was displaced by newer, more competitive cars in its class. ITRs are more favorably classed and have not been displaced by newer, more competitive cars.

As to the merits of each design that is a VERY complex comparison. All things being equal clearly the double a-arm suspension is superior to macphearson struts. A well designed double a-arm has improved geometry which results in reduced bump steer, dynamic roll center movement and a more favorable camber curve than even the best mac-strut suspension.

This doesn't mean that there aren't examples where an excellent mac-strut design isn't superior to a bad double a-arm design. There certainly are. The case of the 6th gen Celica vs the ITR is a good example of all things NOT being equal. The two cars are not similar enough for direct comparison.

What typically makes a good stock class autocross car, without consideration of classing, are fairly simple criteria. Tire size, weight, camber, power, gearing and suspension design. The ITRs double a-arm front suspension means that static camber isn't as much of an issue as it is for the Celica. While the Celica has the benefit of crash bolts that give it considerable static camber, that in itself is a negative as the excessive static camber reduces acceleration and braking grip. But that isn't the only issue separating the two cars. The Celica is heavier and that is its downfall in direct comparison with the ITR.

Realize that the two cars were not designed as autocross competitors. The ITR was a development of the standard Integra as a sport or competition model as is Honda's practice. The Celica GTS never had such a specialized version.

As for the video you posted, that's hardly evidence as to the superior car. The conditions favored the AE86 and it is impossible to know if the two cars were equally prepared.

As a general rule, rear wheel drive is preferred over front wheel drive. Weight distribution is better and having the front tires do braking, turning and power application is far from ideal. Note that you never see a purpose built fwd racecar.

Of course there are examples where the two designs can be compared directly with there respective limitations minimized. D Prepared is probably the best example of direct comparison. The Mk1 MR2, with macphearson sturts all around runs against the Miata with double a-arms all around. The two cars have similar engines of the same displacement, the same minimum weight, use the same size wheels/tires and the prepared rules package allows the car builder the lattitued to minimize each designs limitations.

I have been competing in a DP Mk1 since Nationals of '05. Since '06 the class has been exclusively MR2 vs Miata. To date, my Mk1 is clearly faster than the Miatas. I have extensive experience tuning strut suspensions and worked hard to find and eliminate the Mk1's shortcomings. I have done that successfully but at the expense of other chassis dynamics.

Even in this class, there are other "human" factors involved. Do the Miata competitors have the same level of developement? Are the driver's as capable? All we can do is speculate.

Clearly, I would prefer to use double A-arm suspension. Would my car be faster? Perhaps, but only marginally. The point is that the mac-strut car can compete in most circumstances.

-Steve

 

Ideally, the double wishbone is a better design. Both can be very well designed. BMW and Porsche have both used struts in the past, and they both obviously build very good sports cars. That said... "competitive" in a class only refers to what that car is up against. An H-stock Mazda 3 sedan is more competitive than a regular C5 Corvette. Doesn't mean that the suspension is better... just that it's classed more favorably. The C5 still has more power, more tire, better suspension geometry, better vehicle dynamics, etc.

 

Thanks guys, I really appreciate the insight from those of you who have driven, or have competed against these cars. I think my interest is more in what these cars can do relative to each other when their suspension weaknesses are tuned out. How much of a handicap is having strut suspension. Maybe I should ask it this way: if you were to take your fully prepped DP car and change only from struts to A-arms, what kind of time difference would you expect to see? (I know this generally isn't possible, it's just a hypothetical).

What originally got me thinking about this was just wondering why I didn't see more celicas being tuned and raced on road course or autocross. Keep in mind that in Japan, you could get an SS-III 6th gen celica at the same time the ITR was out which had the 200hp Beams engine and Superstrut suspension up front (same effect as A-arms) and yet we never see these celicas or the Gt-Four for that matter being raced, but we see ITRs everywhere.

I am probably putting too much stock in what I see in Best Motoring videos. I've never seen a Supra on a touge video either, but that certainly doesn't indicate that Supras are unpopular cars. I suppose it may have been a price thing for the most part. Celicas have usually been more expensive than their Honda counterparts and not always better performing.

How do you think a 6th gen celica upgraded to SSIII spec would do in autox? Do you think swapping out the JDM Superstrut suspension would be worth it, or would the money be better spent sorting out a good strut suspension setup? How would swapping to JDM spec (engine and suspension) affect it's classing?

Thanks for your help everyone.

J.

 

Maybe I should ask it this way: if you were to take your fully prepped DP car and change only from struts to A-arms, what kind of time difference would you expect to see? (I know this generally isn't possible, it's just a hypothetical).

Actually, changing the suspension from strut to A-arm is not only POSSIBLE in DP, it allowed by the ruleset. I'll let Steve (XHead) speculate on improved time difference, if any.

What originally got me thinking about this was just wondering why I didn't see more celicas being tuned and raced on road course or autocross. Keep in mind that in Japan, you could get an SS-III 6th gen celica at the same time the ITR was out which had the 200hp Beams engine and Superstrut suspension up front (same effect as A-arms) and yet we never see these celicas or the Gt-Four for that matter being raced, but we see ITRs everywhere.

ITRs everywhere? The seventh generation Celica WAS classed favorably in GS by the SCCA for a number of years. For those of us competing in GS at the time, in other cars, we called them Cicadas, because there were so many of them for awhile. The Mini S fixed that.

I am probably putting too much stock in what I see in Best Motoring videos.

:smile:

I suppose it may have been a price thing for the most part. Celicas have usually been more expensive than their Honda counterparts and not always better performing.

Price has little to do with autocross attendance numbers of a given make/model. Overall performance and favorable classing is the key to being a commonly autocrossed car, again, as mentioned above. Ultimately the Celica was underwhelming for applications in autocrossing, and was only favorably classed for a while

How do you think a 6th gen celica upgraded to SSIII spec would do in autox? Do you think swapping out the JDM Superstrut suspension would be worth it, or would the money be better spent sorting out a good strut suspension setup? How would swapping to JDM spec (engine and suspension) affect it's classing?

IMHO, it would get slaughtered. I might be a little harsh on that one.
Minimally the engine swap would move the car to SM, which is home of some very well developed and prepared BMWs, Honda's and EVOs.

Any change in the suspension geometry, without the engine swap would move the car to EP. With enough money, it could compete there.

If you do both, I believe you move to EM.

 

Maybe I should ask it this way: if you were to take your fully prepped DP car and change only from struts to A-arms, what kind of time difference would you expect to see? (I know this generally isn't possible, it's just a hypothetical).

Well, it certainly is possible. The DP rules permit changing the front suspension "type" to double A-arms. But not the rear. Both front and rear could be done legally in XP.

The ultimate effect could only be determined through testing and developement but we can speculate. The difference in the two architechures really comes down to camber curve and bump steer. With a well designed and executed double a-arm setup the car would require less static camber and would have less dynamic bump steer.

To make the car work well on a strut suspension you have to spring the car very stiff to keep it flat and therefore reduce camber loss from body roll, bump steer and roll center displacement. To maintain adequate camber you have to start with more static camber.

The additional static camber reduces tire contact patch in linear acceleration (acceleration and braking). Next, the improved camber curve of the double a-arm setup means you can spring the car softer thus improving net grip. So the double a-arm car will have more net grip than the strut car in both lateral and linear acceleration. The result would be that the a-arm car would gain a few thousandths of a second braking into each corner, another few thousandth from additional apex speed and a very few thousandths accelerating off the corner.

So assuming all of those tiny amounts of additional performance can be exploited at every opportunity, the a-arm car has a potential net gain of somewhere between a few hundreths to a couple of tenths depending on the course. On a rougher surface the softer sprun a-arm car may have a bigger advantage resulting from the more compliant suspension.

I am probably putting too much stock in what I see in Best Motoring videos.

I think you have identified the problem. They are trying to sell videos. There is an entire culture built around Hondas. Toyota has never had that kind of brand identity.

How do you think a 6th gen celica upgraded to SSIII spec would do in autox? Do you think swapping out the JDM Superstrut suspension would be worth it,

Well, I don't know what SSIII spec is so I can't answer that question.

or would the money be better spent sorting out a good strut suspension setup? How would swapping to JDM spec (engine and suspension) affect it's classing?

Changing the front suspension architechure would only be legal in EP, XP and D/E Mod. You don't have to change the rear since its already a-arm.

Note I have not changed the front of my MR2 over to a-arms. Why? Because the cost and effort would be better spent elsewhere. Besides, I am not unhappy with how the car works now. Other aspects of the suspension design and execution are far more significant.

-Steve

 

There was also a SSII 7th gen Celica that had the Superstruts up front.

I have raced two STS prepped GTS Celica's in the past, granted they were not set up that well and my wife and I were not experienced at all BUT the cars did very well.

But like it was said before the 7th gen is a 2500lb car and has to struggle to keep up with the more nimble Civics....although those Saturns are churning up some good times localy.

My wife still wants me to set her Celica up for STS again, but it's so much nicer to take one car then two to auto-x.

 

So if I just swapped the engine but not the suspension I would be classed in SM?

Do the rules treat JDM options differently that fully custom options? To me, there seems to be a big difference between swapping in a Superstrut suspension and swapping in a complete custom double-a arm suspension that the car never came with.

What class do most of the engine-swapped hondas compete in?

Thanks for the help everyone, I think I'm understanding how things work a bit better. If I decide to autox, I will probably run a celica regardless of whether it is a competitive car or not. I'm more in it for the driving skills than the trophies. :smile:

J.

 

If you swap an engine from the same manufacturer then its SM if not then its XP.

All the swapped honda's run in SM.....or should anyway. CRX's and del-sol's in SM2(Dunno if this class is nationaly recognized though)

 

So if I just swapped the engine but not the suspension I would be classed in SM?

Yep.

Do the rules treat JDM options differently that fully custom options? To me, there seems to be a big difference between swapping in a Superstrut suspension and swapping in a complete custom double-a arm suspension that the car never came with.

Nope. SM would consider the engine as legal but other than that, you would have to go straight to XP or Mod.

If the suspension bolted up to the OE points, then it would be legal in SM. Prepared rules allow a change in type for the front suspension. You can't in STS or SP.

-Steve

 

All you could ever want to know about SSS.
http://www.6gc.net/forums/index.php?showtopic=28093
From the comments in that thread it sounds like a bigger headache than just developing a strut suspension anyway. Interestingly, it sounds like Toyota even scrapped it on their (cheater) WRC Rally cars.

All the swapped honda's run in SM.....or should anyway. CRX's and del-sol's in SM2(Dunno if this class is nationaly recognized though)

SM2 is nationally recognized, and this year maybe "someone" in an MR2 will break up the McKee/Strelnieks party at nats?

 

blah blah blah

:2banana:

good that someone who competed in teh 7th gen chimed in.

the 7th gen celica was a fine stock car till LSDs became stock parts. as pointed out before the Mini crushed it immediately. the celica can still be adequate in sts/x and i suspect EM if someone has lots of brains, balls, and bucks.