[raajks]

As others have stated

- Stiffer setup would make a huge difference to the car's handling
- Go for suspension which can be tuned
- Strut bar, anti-roll bar and stablizer's help to keep the car tout

I would also suggest that you PM Megazoid
http://www.team-bhp.com/forum/members/megazoid.html

He is a real good driver that I know personally.
He has nt done much on his v-tec but he takes high speed corners with

1) Left foot braking
2) Scandanavian flick

You can have fun with your existing setup itself, any additions is always a bonus.
He loves to talk about it and has done a Ph D on reading and learning these techniques.

[Ford Rocam]

@pranavt, Most of the the things are very well explained by doomsday,ananth, docg & Mpower. just decide according to your application & budget.

i don't think even D2 is available for OHC from factory.

I have collected some samples of OEM rubber parts used in suspension /chasis components & getting same thing made of Polyurethane from a dear friend, hope it turns out well. once its made, more PU kits should be available for other OHC owners as well at a fraction of cost.

[doomsday]

Originally Posted by Ford Rocam

I have collected some samples of OEM rubber parts used in suspension /chasis components & getting same thing made of Polyurethane from a dear friend, hope it turns out well. once its made, more PU kits should be available for other OHC owners as well at a fraction of cost.

@ pranavt- There you go, local solutions at a fractional cost. But do this only once your shocks are ready.

@ Ford Rocam- Please give us a review once installed, couple of guys in Blore would be interested as well...

[KSM-Vtec]

Well Well Well ...this is going to be an interesting discussion. Why do i see myself saving less in the months to come

[pranavt]

Great stuff here, thanks to everyone who's been offering suggestions.

I guess it's time to get stiffened shocks then. Should I work with my current worn out shocks or buy new ones and stiffen them? Strut brace at the front, as recommended by most of you. Sticking to stock springs for now, I guess. Don't have a problem with lowering the car a tad bit though, if it helps the handling.

Jitu, when are the polyurethane bushings going to be made? I'd love to try and experiment with them rather than waiting since I want to get this suspension stuff done all-at-once rather than having to open it up multiple times.

Tyres will come a little later I guess, as long as it's the final step in this whole game. Jitu, since you stay quite close by, can you recommend someone who will do the stiffening of shocks as per my needs?

[manveet]

Originally Posted by DocG

If you're overhauling the suspension then go in for stiffer springs, maybe lowering the car slightly. The wide tyres are a start.
Next look at getting a front strut bar to help with body flex at high speed corners. It will also help correct some understeer.

Good points. I've done exactly all of the above on my OHC and it handles fine at 140+. Namely, 205 Yoko's, lowering springs and a front strut brace.

[KSM-Vtec]

In fact i think just good quality 205's will make a lot of difference. I have no issues even at 150. The grip level gives me a lot of confidence.

Not sure if lowering the springs is good idea specially with the OHC+mumbai roads
combination.

From what i have read, a strut brace can make or break the entire setup. If the material used does not have the correct level of stiffness/flexibility it can either be ineffective of even harmful in the long run.

Stiffer shocks??? not sure where it is done in mumbai.

[doomsday]

Originally Posted by KSM-Vtec

In fact i think just good quality 205's will make a lot of difference. I have no issues even at 150. The grip level gives me a lot of confidence.

If you upgrade the rubber and leave the suspension stock- you will very soon run into the limits of the setup even if the rubber's potential isn't maxed out. As a result- one might experience more dive under hard braking- coz the rubber will hold out but the suspension won't have enough to keep the nose in a straight line. Similarly during cornering, the roll will also increase because the tyres would now offer a whole lot more grip- the car won't slide easily but the forces acting on it and the weight transfer will now show through increased tendency for the car to roll. Also, as Ananth mentioned earlier- you won't know where the limit is- it will be a sudden and unpredictable transition from grip to no grip, which may be too late to correct. A good setup should provide grip and more importantly the feedback as to where the grip is running out. The confidence depends where you are driving at 150- in a straight line or a fast kink.

[KSM-Vtec]

Well i am running Yoko S Drive 205/45/16 on my vtec with a stock(but new) suspension setup. Not that i do a lot of track driving, but i do not find any inconsistent/unpredictable gripping.

Confidence also depends on who is driving i must say.

Not sure what kind of rubber upgrade will require a suspension setup upgrade...will it be required for a 195 or a 205 or a 225. Difficult to say i guess.

Originally Posted by doomsday

If you upgrade the rubber and leave the suspension stock- you will very soon run into the limits of the setup even if the rubber's potential isn't maxed out. As a result- one might experience more dive under hard braking- coz the rubber will hold out but the suspension won't have enough to keep the nose in a straight line. Similarly during cornering, the roll will also increase because the tyres would now offer a whole lot more grip- the car won't slide easily but the forces acting on it and the weight transfer will now show through increased tendency for the car to roll. Also, as Ananth mentioned earlier- you won't know where the limit is- it will be a sudden and unpredictable transition from grip to no grip, which may be too late to correct. A good setup should provide grip and more importantly the feedback as to where the grip is running out. The confidence depends where you are driving at 150- in a straight line or a fast kink.

[doomsday]

Ok, I had mentioned pulling a lot of "Gs" on an OHC earlier, it wasn't just a metaphor. We were datalogging an OHC after a suspension job and an I/H/E. This is what we came up with- an almost 720 deg roundabout- widening at the entry, tightening near the apex (lol) and widening again just before the exit. Here's a screenshot of the datalog with me in the driver's seat.



Deciphering it-

There are three elements in this log, the first being the speed/lateral Gs against time graph (in the centre), the second being the map i.e. the line taken (on the right) and third is the comparison chart (at the bottom).

The highlighted part in the G's against time graph is the corner entry to corner exit part, difference in the time, speed, distance and Gs shown in the comparison chart at the bottom.

As one can see, the corner entry speed was 83kph with the exit (calculated at the point where Gs turn almost 0) was 100kph, with the average being around 84kmph. Similarly the Gs, at its max point, the car pulled close to 0.75 Gs- excellent for a street car on a flat surface.

I entered the corner conservatively, the car remained balance on the little throttle liftoff I did when the corner unexpectedly tightened (and dropping speed by some 3kmph as a result), and hug its line (usually stock cars start sliding at the first sign of lift-off) and balance its movements just on the throttle- (very important). I never felt the need to move my foot at all after that first bit- and no big steering movements as well. Even the tyres didn't protest- and yeah they were some 195 Turanzas- definitely not the best things to get the job done.

This is the kind of confidence I look from a car, and yeah I had driven it only 4-5 kilometers before this and mostly in a straight line. I reckon I could've pushed a little more, but it was quite late and we had other stuff to do. But not a bad result IMO. Clearly shows the supension upgrade did its job. I've driven stock OHCs and seriously I wouldn't have pushed half as hard as what I did in this case.

[KSM-Vtec]

wow thats some good study, and backs up the fact that a good suspension setup can go a long way in making one more confident.

But what i am saying is something different, upgrading to better tyres is a simpler/easier and more cost effective way of getting better stability at high speeds. This may not be the best we can reach but will go a long way for sure.

Originally Posted by doomsday

Ok, I had mentioned pulling a lot of "Gs" on an OHC earlier, it wasn't just a metaphor. We were datalogging an OHC after a suspension job and an I/H/E. This is what we came up with- an almost 720 deg roundabout- widening at the entry, tightening near the apex (lol) and widening again just before the exit. Here's a screenshot of the datalog with me in the driver's seat.

Attachment 141108

Deciphering it-

There are three elements in this log, the first being the speed/lateral Gs against time graph (in the centre), the second being the map i.e. the line taken (on the right) and third is the comparison chart (at the bottom).

The highlighted part in the G's against time graph is the corner entry to corner exit part, difference in the time, speed, distance and Gs shown in the comparison chart at the bottom.

As one can see, the corner entry speed was 83kph with the exit (calculated at the point where Gs turn almost 0) was 100kph, with the average being around 84kmph. Similarly the Gs, at its max point, the car pulled close to 0.75 Gs- excellent for a street car on a flat surface.

I entered the corner conservatively, the car remained balance on the little throttle liftoff I did when the corner unexpectedly tightened (and dropping speed by some 3kmph as a result), and hug its line (usually stock cars start sliding at the first sign of lift-off) and balance its movements just on the throttle- (very important). I never felt the need to move my foot at all after that first bit- and no big steering movements as well. Even the tyres didn't protest- and yeah they were some 195 Turanzas- definitely not the best things to get the job done.

This is the kind of confidence I look from a car, and yeah I had driven it only 4-5 kilometers before this and mostly in a straight line. I reckon I could've pushed a little more, but it was quite late and we had other stuff to do. But not a bad result IMO. Clearly shows the supension upgrade did its job. I've driven stock OHCs and seriously I wouldn't have pushed half as hard as what I did in this case.

[doomsday]

Originally Posted by KSM-Vtec

But what i am saying is something different, upgrading to better tyres is a simpler/easier and more cost effective way of getting better stability at high speeds. This may not be the best we can reach but will go a long way for sure.

Yes, definitely. Provided you get the right stuff- in terms of size and grip. Get the combination wrong can it can get all wrong. I drove this car (OHC VTEC) a friend bought from Bbay, it was shod with some 205-section 16" Yokos- some S Drives out front with another set of Yokos (cant remember which one, the guy said its OEM on an A4) . Trust me it was horrible to drive- may be some alignment would have helped, I dunno and not to mention it took ages to cross 160, and was as stable as a Top when once it got there and you wanted to slow down. For christ's sake, a bone-stock 1998 Type 1 OHC with tonnes of blow-by (close to 150 compression across all cylinders) was able to smoke it from launch to 250-260 meters. That left nothing more to say and that dude went and picked up some 195s and a set of 14" OEM rims the next day.

Tyres form a crucial part of the car dynamics equation- after all rubber is the only contact patch between the car and tarmac. The right choice will definitely go a long way in improving the way a car communicates.

[ankitahuja]

I am enjoying every bit of conversation on this thread.

What do you guys feel about a 1998 Type 1 OHC with 195/50/R15 tyres. Running stiffened shocks and stock springs with a strut brace up front.

Are there any specific ways to get your balancing and alignment done in order to enhance the handling in any way?

[Mpower]

Originally Posted by doomsday

The thing is, once you upgrade the struts, without upgrading tyres- they will soon max out- especially during sudden braking at high speeds since OHC brakes are extremely effective and do not fade even under repeated torture. The stiff suspension setup makes the rubber reach its limit very quickly, under braking and to an extent- under cornering.

Tires will max out sooner? Can you elaborate why with a technical explanation?
Actually its the completely opposite.

My first question to him was what tires he was running. I am assuming he is having half decent tires with stock alignment since he's an enthusiast.
My comment on Konis was in general. D2 and Hotbits are nowhere in the same league as Koni, Bilsetein, Sachs and Tokico.

[pranavt]

@Mpower: Goodyear GSD2s with stock alignment. They're categorised as Performance tyres I think, but they're definitely not upto scratch.