Looks like this will be the first year for an XP discussion.

I plan to convert my EVO from road racing to Solo competition this year and do not wish to run the restrictor required for FP so the ideal choice seems to be XP.
The primary changes I will be making are scaling back from the GT35R to a BBK with the Buschur poted/coated stock manifold, changing brake pads to something more suited for Solo, sealing up the vents in the front fenders to adhere to the rules, sealing up the openings on the firewall to adhere to the rules, changing my alignment to something more dedicated to Solo, David working his magic with a new tune (Q16 as the fuel choice), and adding a few Buschur light weight parts such as the mustache bar. I am also still on the fence about switching to a stroker motor. I like the thought of being able to rev to 9000+ RPM if needed rather than shifting to third on courses that are more open so the 2.0 may stay.

I currently have a set of 295/30-18 A6's that I will start the year on and will also be ordering a set of 315/30-18 A6's to see which is a better choice for the car. I am thinking the 315's will be the choice in the future. Both of these sets will be mounted on Enkei NT03+M 18x10.5 rims. I will also be buying some rain tires to put on my Gram Light 57F 17x8.5 rims. Those will be Hoosier Wet Radials in a 275/40-17.

The biggest problem I need to deal with in this class will be weight. My car is a bit of a pig at 27xx lbs. I am hoping that the grip of 315's and Buschur power will help overcome that though. There are also alot of things that I would like to do to lighten up and one that I don't know if I want to commit to yet. A half size radiator and lightweight drive shaft are two that I will for sure be doing in the future. I would also like to cut out the rear trunk area and tin that in. One of the other major places that I can save weight right now would be by removing the cage in the car. I am sure there is well over 100lbs to be saved there. If I calculated right, according to the class rules my car could be as low as 1900LBS I have a very long way to go

I am currently signed up for the East Coast Championship in Blytheville and plan to also attend the Central Divisional, Nationals, the Michigan divisional at LAP, and all the regional Milwaukee events I can get to. I look forward to everyone's feedback and sugestions, warmer weather, and soicalizing with other EVO owners at the events this year!

 

Whoa. Sounds like a cool build.

Have you talked to Andy, Jarrod, the the Berry's (from texas)?

What are you doing for suspension?

d

 

I have met and raced with Jarrod a few times. I have met Andy as well. I didn't have the chance to meet the Berry's but did see his car at Nationals this year. I ended up in HS with my Mazda 3.

The car has all the RobiSpec goodies (KW coilovers, bump steer correction, bushings, etc) and will have a RobiSpec alignment.

I am really looking forward to being able to drive an EVO again in Solo competition

 

Looks like I am in XP...

Just got this car from by brother...

https://www.evolutionm.net/forums/ev...hotoshoot.html

Requires to much work to get it back into SM I think...

 

Yeah, I would say you would have a bit of work to do in order to get back to SM. XP would be the natural fit for the mods (interior gutting) thus far.

 

As the week went by, I added a bunch more parts to the build.

To lighten things up, I am getting the Buschur mustache bar, center member, and rear diff mounts. I will be switching from the Koyo to the Buschur mini sized radiator up front. Also going to plan on cutting out the rear monkey bars that aren't doing anything. My understanding is that Vishnu originally did or had someone do the cage and the rear bars were not legal for NASA so other ones had to be welded in. There is one set of bars currently in back and a bunch of bars around the rear top ceiling area that can be removed. That should be a good 75-100 lbs or so of weight gone most of it up high in the car. These mods should take well over 125lbs out of the car.

I also ordered Porterfield R4S pads for the Stoptech ST40 calipers. Ordered Stoptech rotors to replace the back factory ones and Porterfield R4S rear pads.

I decided to stick with the Buschur Stage 3 2.0 for now so I can easily rev to 9000RPM+ when needed.

My plans are to got out and see the Buschur Racing family at the end of March or first week of April. I cannot wait to get the mods done and see how the tune turns out numbers wise!

 

With the 315's and stock VIII gearing you should be capable of 77mph @ 9K RPM. That should be sufficient for any track.

If you have any plans to ever track the car again (even just an open lapping day) then I would advise against the small radiator. This year I'm switching back from a small rad to a full size unit. . .

Consider running E85 rather than Q16. It will save you a ton of $$ and you can make great power with it. You had your old car running E85 didn't you? Instead of $50-$100 for fuel every weekend you'll spend about $20 . . . plus your motor will run cooler. . .

Consider a narrower tire for your rains. . . the wider the tire the more water it will have to evacuate at a given speed. . .

Consider an RS aluminum roof swap. Will lower your CG dramatically. . . (dont' think carbon roof is allowed in XP)

5 gallon fuel cell? The stock tank is pretty heavy. . .

If you have the BR Race IC you can save about 20# off the very front of the car by going back to the stocker or a light weight unit like the ARC. This will reduce your polar moment. . .

Titanium exhaust manifold - saves 10# over a ported stocker. . .

If it's a dedicated AX car now - a small brake kit like AMS's drag kit or rally kit. Can save nearly 50# of rotating and sprung weight. . .

Smaller lighter wheels - 18x9.5 or 18x10 lightweight wheels and run 285's - could save 28# of rotating mass.

Just a couple ideas of some places to save weight. I've thought about trying 315's before. It would be really cool to see a back to back comparison of 285's vs 315's. . . but I'd have to cut the heck out of my fenders to make them fit. . . and probably raise the car a bit. . .

 

Thanks for all the tips Jarrod.

On a few of our local track layouts, I have hit 60+ in my HS Focus or Mazda so I could still possibly bump the rev limiter at 77, but I wouldn't think that true of most other larger events that I will be going to. I appreciate the math on that one. I wasn't sure what kind of MPH I could hit if needed.

I think I am going to switch the radiator but keep my old one in the event I can afford to get back into the road racing stuff or do want to do a track day.

I do really like the E85 and it does give great power but the Q16 has some of the alchohol properties and I think I can get a significant amout of power increase with it to justify the cost right now. I also currently have a full drum of it which makes the decision a little easier. With the short autox courses, heat hopefully won't be to much of an issue. I won't have a co-driver so the car will get more time to cool off then yours probably did.

For the rains, I have planned to get the 275/45-17 Hoosiers and put them on the Gram Light 57F's I had on my old EVO. The taller narrow tire should do exactly what you mentioned.

My car started off as an MR so it does have the aluminum roof. Although the roll cage negates that for sure. I should be able to get rid of at least 50lbs up at the top of the roof by cutting out some of the tubing that is not needed.

The IC is one thing that I definitely want to get something in the works for. I need to dicuss that with David and see if he would be willing to do something custom for me. Based on all he has done for me, I would not feel right about running an IC from someone else.

The exhaust manifold was something else that I had considered. I was concerned about losing low end power though. It seems as though all titanium headers give up noticeable power down low? If I were to do the 2.3 in the future though, it may be a better choice for me.

I do have a fuel cell in the car. It is a 10gallon that is fairly light weight. I will plan to run it half full but want to keep that for when I road race again.

It sure would be nice to replace those 14" StopTech rotors with some lighter weight ones. They are heavy and total overkill for Solo but swapping back and forth would be a pain since I am not the most mechanically inclined.

I definitely have felt the benefit of light weight rims with my old EVO. When switching from the BBS to the Gram Lights it was night and day with how the car felt. I have a large investment in the current rims/tires already though and they would be better on a road course so I definitely do not want to get rid of them. I will probably try to pick up a set of light weight rims and run some 285's at some point in the future to see how much it helps.

I should have some data going from 295's to 315's same day/course and will post the results when it happens. The rims will be the same size/weight though. The other trick will be trying to make sure the tires have the same amount of use on them.

You made some really good points. I will have quite a bit of car development to do, being this is the first year running it. Depending on how competitive it is will dictate how far I will go in the future in transforming it most likely.

 

I patched up all the holes in my firewall today. A HUGE thanks to David Buschur for the tips on what to get/do. I bought some very thin 6x18 sheets of aluminum from Menards and used a tin snips to cut out the pieces after making templates with cardboard. I then used automotive seam sealer to keep them in place. Much easier than I expected!

 

Excellent. Sounds like you have it well thought out. I didn't realize your car was an MR chassis. I thought it was an '03 or '04 model. Bonus!

I was just throwing the IC idea out there. I know David is of the bigger is better ideal when it comes to ICs, and of course I knew you would stick with BR. I would do the same in your shoes. It would be great if you can talk him into building a custom setup for you. I would look into a wide/tall/thin tube and fin core. It will be much lighter than any bar/plate style . . . Once you hit the HP ceiling where more is not necessarily better, losing 10 pounds becomes more of an advantage than gaining 10HP. Your car should easily be at or near that ceiling. . .

With the ASpec titanium mani I lost enough low end that I could actually feel it in the seat of the pants evaluation. . . plus $1600 is alot to spend to lose 10 pounds. . .

If you get a chance to test the 275 rains back to back with 245's give it a shot. The results would be interesting. . .

One idea for the radiator if you may be switching back and forth - have AN fitting welded onto the rad. inlet and outlet, and also the motor inlet and outlet. Use AN hose with dry-break QD fittings. You can swap radiators in 5 minutes and not make a mess with coolant all over the ground. . .
http://www.jiffytite.com/motorsports.cfm?subpage=397

I can't wait to see this beast run. I know of an XP evo in Ohio that is in the 24XX weight range - but I don't think he has a ton of suspension development . . . it should be an epic battle!

 

Yep, the car is an 05 MR with the 5spd swap.

Thanks for the suggestion on the core type. I really do not have much experience there.

In your opinion, is a 245 tire typically better at the level of our cars? It seems like that could be getting pretty narrow with the amount of power our cars put down. I suppose it would/could really depend on how much standing water there is.

I had planned to do the AN fittings but was not aware of the QD fittings. That sounds like a great idea and is also appreciated. I will be looking into those.

It should be very interesting to see what the 250 or so lbs does. Hopefully he is a bigger guy and I can get myself back down to 175lb range as that will help make up some more weight difference Is that Kevin Lewis by chance?

I have also heard of people cutting more holes in the floor pan or other possible areas but have not checked the rules for XP on that yet. I don't know if I want my floor pan looking like Swiss cheese although I could cover up the holes with some really light weight aluminum.

 

In your opinion, is a 245 tire typically better at the level of our cars? It seems like that could be getting pretty narrow with the amount of power our cars put down. I suppose it would/could really depend on how much standing water there is.

I had planned to do the AN fittings but was not aware of the QD fittings. That sounds like a great idea and is also appreciated. I will be looking into those.

It should be very interesting to see what the 250 or so lbs does. Hopefully he is a bigger guy and I can get myself back down to 175lb range as that will help make up some more weight difference Is that Kevin Lewis by chance?

I have also heard of people cutting more holes in the floor pan or other possible areas but have not checked the rules for XP on that yet. I don't know if I want my floor pan looking like Swiss cheese although I could cover up the holes with some really light weight aluminum.[/quote]
I have not tested the 245's vs. a larger rain tire. Here is the way I am approaching the subject:
Andy won ESP in '05 in the rain on the stock Advans, while many of the Mustangs and Subies were running 275 width Hoosier rains. The wider the tire is, the more water is has to evacuate at a given speed, so your max speed before hydroplaning will be lower with a wider tire. The lighter the car, the less force there is to push the tire down through the water, so the narrower tire you want. In standing water 300whp is too much to put down. . . all this leads me to believe that a 245 will be optimal for the EVO in heavy standing water.

Now, in drying conditions where you have patches of dry or damp mixed with patches of standing water - the 275 would probably be the tire of choice. . . just depends on the amount of water on course. . . guess we need 2 different sets of rains!

I've never ran a BIG event in heavy downpour with lots of water, but I have run a local event with between 1" and 3" of standing water on parts of the course. . . I beat the next fastest SM car by 8 seconds. . . on stock tires. . .

Don't take my word as gospel. I've been wrong about way too many things. That's just my mind's interpretation of how things "should" work based on the little bit I understand (or think I do) . . .

Yep, the other XP EVO I was talking about is the black beauty owned by Kevin Lewis. Do you know him? His 330 was the most wicked sounding BMW I've ever heard. . .

I have never heard of cutting up the floorpan. Personally I would never do it. If you do, at least when you **** yourself during an off-track excursion you'll have drain holes!

 

That is very good information. I personally have never run with a large amount of standing water so it is very helpful in trying to make a decision.

No, although I have heard his name before. Google knows everybody

Yeah, am very hesitant to do that as well. On the drain holes...I could have used those in St. Lous when the wall was coming at me head on at 80mph

 

The Berry's from TX were able to get their FP car down to 23xx pounds without cutting the floorpan, so that would be the last thing I would do - and only to a car that was dedicated to AX. It would never be good for anything else and you'd have a hard time ever selling it. . .

Since we have an XP thread now, even though there are only two of us really discussing things, I will post up what I think would make the "ultimate XP EVO" shortly. . .

 

I don't think my jungle gym cage will make your list