Which way to go - SM2 or FP

[heavy85]

So now the year is over for the Z - I officially parked it for the winter today after getting home from the autox. Over the winter I am going to section the struts and get some race rubber for it among other things like fix the tranny...again, install aluminum flywheel , electric fan, etc, etc. So I'm debating on which tires to get. I've been running SM2 on really crappy street tires but I'm not totally 100% legal for SM. I dont have heater, wipers, or wiper/headlight controls on the steering column all which technically puts me in FP. Either way I would not be nationally competitive and I am no where near the limit in car prep so I dont feel bad running SM2. So now the question is do I go with slicks and FP which would also allow me to relocate my front control arm pivot up and get rid of the 4 wheel drive stance (currently running with front arms level which has nearly 8" clearance to the rockers!) or stay in SM2 and get some R compound DOT tires? I think the index is very close between the two classes so I could possibly be more competive in FP with the stickier tires but at the same time there are usually a couple cars in SM2 but rarely one in FP. Any suggestions?

 

Thanks

Cameron

[tube80z]

You basically have two options. Two classes you can run in and keep a semi-steetable car on DOT tires. Those are street prepared (BSP) and street mod (SM2). It sounds like you want to do a number of mods that would move you closer to the SM end. From the little that I have kept up with SM it sounds like bolt-in subframes are now legal and that means you can relocated all the suspension pickup points and make the amrs longer.

 

The other option are the three slick tire classes. Those are FP, EM, and the new AP. With the exception of AP, which is a bit of an unknown, you will not have a very streetable car if you intend to be semi-competitive in these classes. Most creature comforts are thrown at right off the start.

 

It's really up to you at this point. I'd opt for a semi-street legal car if I were to do this all over as it helps to get some mileage on certain parts. And if you can truly replace subframes then SM2 sounds as good as any and you're likely to have a few people to run against.

 

Disregarding what PAX says, I think in an older car like the Z that prepared will be faster than SM. Mostly because of what you can do to reinforce the chassis.

 

Cary

[Guest AlsoRanFPrepared]

If you are not legal for SM then running there will be at the mercy of the local SM folks. If you are not competitive it likely wont be an issue but if you become competitive then expect some protests and a bump into FP or EM. Again, it will depend on the local folks you will run with. Even if you are not modified to the limit of the rules, your deletions may get you protested. The first question to ask is do you want to be competitive locally/divisionally/nationally? If you do, either class will present the opportunity to spend lots of money getting there. I would recommend preparing to the rulebook to avoid protest in either case. If you want the car to be "streetable" then SM is a good way to go. Although, the well prepared SM cars dont get driven on the street and are marginally "streetable" given their preparation.

 

If you dont feel particularly concerned over being competitive, then I would recommend E-Mod (as mentioned the new AP may be appealing too). This will allow you lots of freedom to modify and in the end you can have the car that is modified the way you want (provided red-baron wings arent your style). You can still have a very streetable car in EM although it wont necessarily be competitive. You can run any tire compounds you want and based on your choice may avoid some of the safety items required for slicks. Personally, I moved up from BP to FP to EM with my Z because of the freedom to modify and what I believe is a lower cost to be competitive.

 

As for tires for next year. I recommend running some DOT R compounds regardless of the class you are in. Your suspension (perhaps budget?) is likely not prepared for running slicks just yet and the R compounds will be a good next step up from the crappy street tires. After a season on those, you can decide if you want to make the jump to full slicks. Keep in mind, once you get slicks things will have a tendency to break.

 

Hope this helps some,

 

-Mark

[zguitar71]

I run in FP with a full interior. My suspension is a little soft but (200r 180f, illumina's) it does work. I use 15x7 wheels with 23x9x15 r250 goodyear cantilever slicks. I could go with 16x10 wheels but then I could not fit all the wheels/tires into the back of the Z and I would have to run flares. I decided to run FP baised on the thrill of the ride. The slicks are very fast and stick like glue. The car is much faster with slicks than DOT's. My car weighs 2300 pounds with a 1/3 tank of gas and has probably 200 HP. This year we hosted a NORPAC event, there was a SM2 `70 240 there with a full cage, better suspension, higher power motor and a good driver (heavier at 2400 lbs) but I still ran the course nearly 2 seconds faster than he did. It is all in the tires. I would never be competitive at the nationals but I will never go back to DOT's either. I say get some slicks in the stickiest compound available in the size you want and have a blast. Too my surprise the tires last longer than I thought they would. I used them 2 seasons (20 races) and they still have some life left in them (mabey 2 races) but I am getting new ones for next year.

[JMortensen]

I was running F Prepared but that was only because I figured out how to get slicks cheap. I actually found the deal on the slicks when I was running O/SP, then I figured why not and bought some steel wheels and ran in Prepared. I was usually the only one out there in F/P, but I was racing against my old roommate who had an underprepared E/P 510, and I also liked to see the "run whatcha brung" aspect of the non PAXed final results. He and I duked it out for years, each of us improving on what we had and becoming faster and faster. I moved about 4 years ago and haven't autoxed since, my old arch rival has apparently not stopped, and I know he's been FTD at Shasta and has a pretty good rep among the POC crowd and usually is FTD at their slaloms.

 

Being seriously underprepared my PAX results usually put me down to about 30th or so, but my raw overall standings were damn good. Car had a full interior and weighed 2350 had an 8.5:1 compression L28 with SU's, later got Mikunis. I was running a 250/45/15 Yokohama road racing slick which really wasn't the best for autox. I had similar results to Chris as far as tire wear and I usually ended up chucking my tires because they were getting too hard, not because any cords were showing.

 

Basically if you want to be competitive you better have a big bankroll. If you want to have fun I'd suggest the Prepared or Mod classes because you have more flexibility in how you build the car and you can run the stickier slicks which to me is part of the fun. The faster the car the more fun it is.

[heavy85]

Well I think I'm thoroughly unsure but am leaning towards FP for the sheer speed of it - would be fun to beat that damn SS Z06 who got FTD two races ago. This weekend there was a BM Formula Continental who beat everyone by about 4 seconds (and all but one by about 6 seconds) but other than that there usually isn't any serious Prepared or Mod cars out there so it would be fun to have a shot at raw FTD. Breakage has me a little worried, though, just for the sake that I dont have a tow vehicle but otherwise the more I type the more I'm leaning towards slicks and FP. Since I only plan on racing about a half a dozen times a year (four kids under 10 kind of limits that) I am not going to buy a new set every year (or maybe even every two at that rate) so I would rather get something that I'll keep rather than starting with DOT's then moving to slicks a year later. I raced DOT's years back on my old GTI and slicks on go-karts fewer years back so I have an apples to oranges comparison but in general understand the very high grip slicks offer - bruised ribs anyone? I dont know how much difference there is between the latest DOT and slicks as far as grip goes but I'm guessing a lot.

 

So any recommendations on slicks - size, compound, rim diameter, where to get them either new or used, etc. I'll probably use Diamond wheels to keep costs down unless I can find some decent used wheels.

 

Thanks

Cameron

[zguitar71]

If you can fit them a set of 16x10 (-12 offset I think, you would need to double check that though) wheels with goodyear 23.5x16x10.5 in the r250 compound would be great. You would need coilovers and flares (which you have). You might have a hard time fitting them in the car to go to the races. That is why I use 15x7 (-12 offset) wheels with 23x9x15 r250 goodyears (+ I do not have flares). The difference between the larger wheels and mine really is not all that huge. What ever size you get get the r250 compound. The higher number compounds are not sticky enough and the lower numbers are too soft and over heat on warmer days. I race a guy in a `02 vette in SS, he beat me for the first time at the end of the year (after 2 years of trying). Of course my tires were 2 years old and his were new, I drove like $hit that day too. You should be able beat a SS vette with the slicks and some good driving.

[johnc]

If you don't intend on competing at a National Tour or at the Nationals why don't you build the car exactly the way you want and run it in your local "run whatchya brung" class. A National level (trophy) SM2 or F Prepared 240Z will cost around $25,000 at the low end with the FP car being the cheaper option.

[JMortensen]

I think the same tire in a 15 should be faster than the 16. I know the trend is against me, so I suppose I can only point to Cary as proof of my point. He runs 13s.

[tube80z]

I picked 13 inch wheels for a smaller diameter to ge the car lower without messing up the geometry and have less rotating weight. After a lot of research I picked formula atlantic tires because of availability (cheap on the used market) and they had the latest in constructions. A lot of people have told me this won't work -- I didn't listen.

 

I run Hoosier tires in R25A (when it is coler) and R35 when it is warmer. Just remember that different tires have different spring rates and this all has a major impact on your suspension tuning. Pick something and stick with it or you will be chasing your tail.

 

Cary

[heavy85]

OK so I'm leaning towards 15" but those 13's seem like a good idea (well except for the ugly factor which is not a real concern). Cost and weight should be down 15 vs 16 and the 13's well they kind of scare me as I want something that will work without a huge amount of development due to my limited race schedule so I'm afraid they would take some work but again just speculation. So where can I get these good deals on slicks?

 

Thanks

Cameron

[tube80z]

OK so I'm leaning towards 15" but those 13's seem like a good idea (well except for the ugly factor which is not a real concern). Cost and weight should be down 15 vs 16 and the 13's well they kind of scare me as I want something that will work without a huge amount of development due to my limited race schedule so I'm afraid they would take some work but again just speculation. So where can I get these good deals on slicks?

 

I should point out that 13s do take some work to get good brakes and steering arm clearance.

 

For tires you can check e-bay, local race tracks, http://jbracingtires.net/index.htm, and other sources. I get most of mine from John and he's always treated me very well.

 

Tires are bagged when not in use, mounted with nitrogen, flipped every three events, and treated with Formula V as needed. I start with two sets and after a year I rotate in a new set. I keep a running log of their use and match them by diameter. It's important to do this with bias ply slicks as they grow as they are ran and you can end up with weird handling if you don't adjust for this growth. I try to keep tires matched by diameter on each end. Radials needn't worry about this. And I get the car off hot tires as soon after a run as possible. It all helps to make them last longer.

 

Cary

[gramercyjam]

If you do stick to autox and someday go to the nationals, you might still find several 240Z's in FP. There are none currently in SM2 that I am aware of.

 

We have several cars down in Texas that run in FP. It's nice to have some people in your class to compete with. I disagree with John about $25K to get a nationally competitive car together for FP. If you can do all the work yourself, and you have some fab skills, and luck out scrounging up some used parts, you can build a car that will compete for substantially less. Now that's the easy part. The trick is driving well enough to trophy.