Best chassis for autocross?

[yoitsmatt]

I'm new here and seriously considering making the jump to Fmod (after i sell a motorcycle) , I am a long time Solo competitor in Stock/street, ST classes and Kart mod. I am a dealership tech by day so working on the car isn't a big deal, but id rather drive than fix crap (why i'm no longer in KM). Problem is I don't have any local guys to pick their brain, beg codrives, etc. I know the question whats best is too general,and depends on personal preference,

i guess what i'm looking for its whats worst, wont work ,don't waste you money on. and some general differences??? my primary focus will still be autocross but i would like the option of track and maybe hillclimb as well. Also i'm a little bigger than average, 6ft 200lbs 32 inseam if that matters for some chassis??

Thanks
Matt Feeney

[tombu-mi]

Stay away from anything with a Kawasaki engine - they are way past their time. Also, Legends cars are legal for FMod, they may be fun, but they aren't competitive (yet).

As far as a chassis goes, if you look at the Solo Nationals, pretty much every one is represented. I'm just a little smaller than you and fit fine in my Invader (a newer version of a KBS). Any car that is strictly set up for autocross and has the sides cut down gives you infinite shoulder and elbow room. That said, the best thing to do is go and sit in any car you are interested in to see how it fits your body shape.

If you have an F500 totally set up for autocross, they probably aren't ever going to let you run any track days, or for that matter hillclimbs. To run hillclimbs, you'd have to have a road race legal F500. I have, however, run time trials in my car.

A friend of mine in Indianapolis is selling my old car. It has an updated engine, but not chassis, but you'd fit in it easily. Here's a link to information on it - https://drive.google.com/file/d/0B7n...VodzZuS2M/view

(actually, I don't know if this site accepts links, if the link doesn't work, you can find info on it on the SCCA F550 & Fmod site on Facebook, also if you have any other questions that I can help you with, feel free to PM me)

[yoitsmatt]

Thanks for the info, first mistake avoided, bike guy thinking ; Kawi = good

[Jnovak]

Take a look at what car has won Fmod for the last 3 years in a row.

[tombu-mi]

Last seven Solo National Championships

Year Driver Chassis

2017 Jason Hobbs Novakar
2016 Jason Hobbs Novakar
2015 Jason Hobbs Novakar
2014 Darren Seltzer Raptor
2013 Darren Seltzer Raptor
2012 Jeff Colegrove Red Devil
2011 Jeff Colegrove Red Devil

In 2012, Jeff left solo to (I think) race carts
In 2014, Darren left solo to road race
I would guess that at least Jeff would say that he changed his car so much that in the end it was no longer a Red Devil

[Jnovak]

Last seven Solo National Championships

Year Driver Chassis

2017 Jason Hobbs Novakar
2016 Jason Hobbs Novakar
2015 Jason Hobbs Novakar
2014 Darren Seltzer Raptor
2013 Darren Seltzer Raptor
2012 Jeff Colegrove Red Devil
2011 Jeff Colegrove Red Devil

In 2012, Jeff left solo to (I think) race carts
In 2014, Darren left solo to road race
I would guess that at least Jeff would say that he changed his car so much that in the end it was no longer a Red Devil

I designed the rear axle and suspension on Jeff's car. Just for solo.

[yoitsmatt]

Take a look at what car has won Fmod for the last 3 years in a row.

thanks i planned on watching but run days didnt work out this year....

[ricky bobby]

Personally I don't think there is a dominant chassis in Solo. It comes down to driver and setup.
Jay designs fine cars, and has been successful with his builds. No denying that, as his cars have been successful at both RR and Solo.
Hobbs has been in the class awhile now, and is a really good driver. He constantly improves the car, as most of the class does.
The mix of chassis in the trophy positions should tell you that there isn't a dominant chassis.

Things to look for:
1) If you can get a car already setup for Solo, do it. If you get a RR car, expect to do some work on it to get it to work well at Solo.
2) Rotax engine and CVT are the quick drivetrain package in Solo. Only 1 person has showed up at Nationals with a MC engine/drivetrain and he is off the pace. Most of the grid still has a 493 or 494, but the 593's are creeping in (Hobbs has a 593).
3) Everything shakes... so expect the "care and feeding" to be more than your street cars. We work on these almost as much as KM. You have to keep an eye on everything.
4) FM is a super fun class. We are the CP of Mod.

Any other specific questions... ask away.

-Will

[Jnovak]

Personally I don't think there is a dominant chassis in Solo. It comes down to driver and setup.
Jay designs fine cars, and has been successful with his builds. No denying that, as his cars have been successful at both RR and Solo.
Hobbs has been in the class awhile now, and is a really good driver. He constantly improves the car, as most of the class does.
The mix of chassis in the trophy positions should tell you that there isn't a dominant chassis.

Things to look for:
1) If you can get a car already setup for Solo, do it. If you get a RR car, expect to do some work on it to get it to work well at Solo.
2) Rotax engine and CVT are the quick drivetrain package in Solo. Only 1 person has showed up at Nationals with a MC engine/drivetrain and he is off the pace. Most of the grid still has a 493 or 494, but the 593's are creeping in (Hobbs has a 593).
3) Everything shakes... so expect the "care and feeding" to be more than your street cars. We work on these almost as much as KM. You have to keep an eye on everything.
4) FM is a super fun class. We are the CP of Mod.

Any other specific questions... ask away.

-Will

I agree Will.

[Tom Grossmann]

I've been autocrossing an 87 Novakar locally (Vegas region SCCA) for 2 1/2 years. We have some nationally competive drivers in various classes as well as 2 national champs (KM). Most of the time I finish behind the karts but ahead of the cars. My car was a road race car and I did my first end with the road race set up. With the road race set up the car will understeer fairly heavily but changin over to the autocross set-up was very striaght forward; some alignment changes and running the wider rear slick on the fronts. Everyone here was very helpful. Jay Novak gave me a bunch of information and former national champ Jeff Colgrove also gave me good advice. Years ago I road raced bikes so my body doesn't need the beating I find Karts to be. As for the maintenance; my son autcorssed a junior Kart for several years and the F500 doesn't need anywhere near that kind of maintenance. As long as everything is safety wired or lock nutted it's fine. My car even has one of the old obsolete AMW engines that had a reputation of being unreliable and I've never had a problem with it. The only routine service items are the primary and secondary clutches, now you don't have to derive them at all for many events but you will quickly find that you become less and less competitive if you don't.

[TedV]

Personally I don't think there is a dominant chassis in Solo. It comes down to driver and setup.
Jay designs fine cars, and has been successful with his builds. No denying that, as his cars have been successful at both RR and Solo.

2) Rotax engine and CVT are the quick drivetrain package in Solo. Only 1 person has showed up at Nationals with a MC engine/drivetrain and he is off the pace. Most of the grid still has a 493 or 494, but the 593's are creeping in (Hobbs has a 593).
3) Everything shakes... so expect the "care and feeding" to be more than your street cars. We work on these almost as much as KM. You have to keep an eye on everything.

Driver of the MC car came from KM. He's a larger guy, him and his wife have fun driving the Wildcat chassis. I'd like to see how a Novacar with MC power would do at autocross with a well tuned loose nut behind the wheel. I have a KM and CM (in mothballs) but have tire warmed someone else's CM car the last 2 years at Nats. I personally hate 2 strokes, carbs and CVT clutch tuning. I wish F600 was established when I purchased my CFF. You will have to nut and bolt any Mod car. CM, KM and I suspect FM cars are easier to work on than Street based cars. My KM with ICC maintenance is clean carb if it hasn't run in a few months, clean dry clutches, make sure fresh batteries are in the dash, charge the motorized lift and water pump batteries, check nuts and bolts are not loose, confidence start it before an event. It did take a while to get it this simple as the previous owner had great driver skills, but lacked mechanic skills. I'm the opposite, better mechanic than driver. Hit some national events, talk to the FM drivers. Pretty sure they will let you test fit their cars if you ask nicely. Many of the older Red Devil chassis do not get along with my shins. Look in to what it takes to keep the CVT tuned. Seems like a black art is involved there.


all that to say..... keep up at doing your research, Buy the best set up, working, turn key car you can afford, unless you like to turn wrenches and chase setup

[yoitsmatt]

Personally I don't think there is a dominant chassis in Solo. It comes down to driver and setup.
Jay designs fine cars, and has been successful with his builds. No denying that, as his cars have been successful at both RR and Solo.
Hobbs has been in the class awhile now, and is a really good driver. He constantly improves the car, as most of the class does.
The mix of chassis in the trophy positions should tell you that there isn't a dominant chassis.

Things to look for:
1) If you can get a car already setup for Solo, do it. If you get a RR car, expect to do some work on it to get it to work well at Solo.
2) Rotax engine and CVT are the quick drivetrain package in Solo. Only 1 person has showed up at Nationals with a MC engine/drivetrain and he is off the pace. Most of the grid still has a 493 or 494, but the 593's are creeping in (Hobbs has a 593).
3) Everything shakes... so expect the "care and feeding" to be more than your street cars. We work on these almost as much as KM. You have to keep an eye on everything.
4) FM is a super fun class. We are the CP of Mod.

Any other specific questions... ask away.

-Will

I have always been a fan of blue loctite and safety wire, and honestly KM wasn't so bad, i raced harescrambles for years so nut and bolt before every race was the only way things didn't fall off. when I jumped into KM i didn't do it smart, wrong chassis wrong engine, too heavy driver. and locally we don't have many smooth lots ( so even our 2 time national champion leaves his Kart home so it wont get broken). thanks for the great info!

[yoitsmatt]

When things break, wear out, fall off and get lost, which chassis are easiest to find parts for? or is most of it universal? or is it just call this guy and done? My car has an oddball chassis only built about 18 months and even though the company was still in business they didn't have stuff for it other than the basics.

[clint]

When things break, wear out, fall off and get lost, which chassis are easiest to find parts for? or is most of it universal? or is it just call this guy and done? My car has an oddball chassis only built about 18 months and even though the company was still in business they didn't have stuff for it other than the basics.

Invader/KBS, scorpion,nova car. In that order

[mmi16]

Invader/KBS, scorpion,nova car. In that order

You overlooked Red Devil - Don Hanley still supports his cars, however, you may have to give him the broken part so he can reproduce it as he has changed most every component over the years and I suspect does not have drawings for each and every change so that you can just call up and order something.

Damaged a front spindle assembly on my 86 Red Devil a number of years ago, sent Don the broken one and in a week or so I had a new one.

If one has fabrication abilities, making the parts for F500 cars is not that difficult.

[B17overhead]

You've already received generally good advice on not getting a Kaw powered car- but there are some very good chassis worth doing an engine swap on that still might have a Kaw in them like older NovaKar, older KBS, older Maverick, Sidewinder.

It is time consuming work to do a 493/494/593 Rotax swap to a Kaw car, but depends on your machine shop skills and chassis's room to fit the motor and exhaust. These cars mentioned are almost rear engine rather than mid-engine cars because the engine sits back so far- so you will need angle mount blocks to tilt a 494 forward (494 carbs sit low on the block) to clear the rear axle. A few people have done a 494 swap where the carbs go under the rear axle -but while the result is about the same and maybe a little more elegant looking, its usually harder to do. 493 and 593 are reed valve rather then rotary valve and carbs are higher on the motor, so they automatically like the "above axle" route.

Stay away from older Red Devil than about 1995 unless someone has done a lot of re-engineering. Same for old Zinks, too.
Almost anything you find will need special attention to cooling for solo. Min rad that will work typically is a pair of VW siroccos- but bigger is better. I like bigger rads than Siroccos. The best threads are on F500.us if you want to learn about cooling.
-Chuck

[Jnovak]

I hate to say this but the only good thing about VW radiators is the cost. I tested every commercially available radiators and the VW rads had the worst heat transfer of any radiator ever tested. Period end of post.

[B17overhead]

I've never been impressed either, Jay.

However, in the solo situation, perhaps more like drag racing, radiator heat to air transfer efficiency may not be as critical as one might think.

Total volume of coolant and heat content of the coolant is because the bulk of the actual cooling takes place after each run. Evaporative conduction cooling from spraying water on the rad is also incredibly more effective than running an electric fan. Here in AZ when the surrounding air temp can be 114F or higher at events, water to air cooling really starts to suffer.

[Jnovak]

I've never been impressed either, Jay.

However, in the solo situation, perhaps more like drag racing, radiator heat to air transfer efficiency may not be as critical as one might think.

Total volume of coolant and heat content of the coolant is because the bulk of the actual cooling takes place after each run. Evaporative conduction cooling from spraying water on the rad is also incredibly more effective than running an electric fan.

Thanks.. great point. I was always looking from the perspective of road racing.

[B17overhead]

On the other hand, Jay, I don't know anyone who does more careful testing than you do and truly figures out what works to win at whatever you make up your mind to compete in.

"One test is worth a thousand expert opinions."

For anyone looking for good technical discussions on F500, both road and solo oriented, where many including Jay have contributed, one can do a search there on topics like: cooling, suspension, pucks, or clutching on F500.us

There is a list of current chassis mfg. contacts there, as well.