LGT and autocross

Right now I have a 03 350z that I need to get rid of because I need a car with more than 2 seats so I figured to go Subaru. Dont want a WRX/STI due to insurance, and other reasons. Legacy seems pretty sweet.

 

The thing is i'm probably going to get the previous generation since I don't buy new cars.

 

I autocross currently with the 350z in BSP (tires, suspension, plenum spacer), with the LGT i'm going to upgrade the suspension pretty much as soon as i get it among other things. I was wondering if transmission is the only concern and the fact I do autocross should I get a Spec B or would the 5MT be better for this? In my 350z in any autocross course i've been on I never have to even go to the 3rd gear aside from one "fast" course. I wonder if Spec B would be the same?

 

I've searched the forums and people only talk about "track" (drag strip)

Search for posts from whitetiger and XenonK, you'll find a lot of AutoX information on the LGT from them.

 

I have a sneaking suspicion that a SpecB would need to use 3rd on "fast" courses. However, I have the same suspicion that the 5MT will, just less frequently.

 

The SpecB 07+ has a better rear diff, which might be worth something, and can use the STI front diff as a drop in, since SP allows you to add one. I'm not sure how it really stacks up with the 5MT. I haven't really seen a "Spec B vs 5MT LGT for AutoX' type comparison, so this could be a handy place to have that discussion if the veterans are willing to chime in.

I'm in second after launch nearly the entire time for all courses I have run thus far. With a tune the rev limiter moves up a bit giving a bit of room for the rare faster courses.

Thanks for the info.

I have the 5 MT and have never gone into 3 rd gear at an event (actually tried it once but lost time on that run). I had the same question for a spec B in my club and asked him if he ever went to third (since he has 6 gears vs 5 mine). Nope, never did either.

5 eat works good too , if you get in very slow speeds in 2nd the torque will let the rpms jump up and allow the car to pull with out having to shift down.

I've never autocrossed the LGT before, but I have autocrossed in other cars, including my old 07 Mazdaspeed3 with a 6MT. I will say that for low speed driving, especially with a turbo car, the 6mt will be better because there is less of a gap between 1st and 2nd. On some slower corners, you will find that you have a big lack of power in 2nd because you will be below the boost threshold. With the 6MT you might have to shift into 3rd if there is a long straight, but that's pretty unlikely based on the autocross tracks I've seen. The improved diffs with the 6MT would be a benefit as well. I get wheel spin on the front on tight corners even at stock power levels. Less body roll will help, but so would a front LSD.

I autocrossed once on the stock suspension. It was laughable and I swapped everything within 6 months. OEM springs, struts, and brakes - even in "specb" form, are not for autocross. Regarding the driveline, I agree with others in that the spec.b would be the way to go. Its also preferable if you decide to go with power mods above stg 2.

Funny, the member with the Spec B in my club does very well in B stock and no suspension upgrades. In fact he refuses to modify it . He does use Kuhmo V 710 tires. His times are really good and i have never seen him lose in B stock class and even beats many others in modified classes (like STX, ESP sometimes too).

 

I used to autocross my 05 WRX which is a 2 l and Non Variable valve timing . Really lacks low end torque. Our LGT's are a pleasure to autocross form the Low end torque perspective. That is of course unless you get a significantly bigger Turbo like an 18G or 20G (which favor high speed track duty rather than autocross). Our biggest nemesis is our portly weight.

I don't know what kind of cars are in b stock class, but they must be the kind that have ridiculous squat, dive, and body roll. The spec.b does decent becuase it has RE050a tires... not because of its suspension.

Don't get me wrong I hate stock as much as you do. But some can drive and manage that soft stock well , or at least they like it that way. Its the indian not the arrow, but it does help have a sharpened arrow. I couldn't stand when it when I drove My stock LGT wagon on autocross but I least I had fun doing it.

The lightest LGTs are the non limiteds, Spec Bs are the heaviest.

 

What class do you have in mind? SP, SM, or Prepared?

 

I've never hit 3rd in an autox. Going to 3rd is frowned upon by the autox gods, so most fast courses you can hit the top of 2nd which can be 65mph with the right mods...on a 5mt anyways.

SpecBs are heavier because of the 6sp and R180 diff, both potentially desirable. Also, if you're going to change the suspension, SpecB stuff is worth something, stock GT not so much.

 

Classing is the same for all LGTs: D stock, E super stock, E street prepared. 5MT or 5EAT, LGT or SpecB, sedan or wagon.

I agree the 6spd is desirable, but not if we're talking strictly autox. You'll never be able to get back that extra 240lbs that the 07+ Spec B carries over the non-ltd LGT.

 

You might make more selling parts off of a Spec B, but you'll pay for that when you initially buy the car. Moot point, especially since the idea is to upgrade right to SP.

 

Personally, I'd get the non-ltd and then pick your tires and wheels based upon what kind of courses you typically see. That will erase any gearing advantage the Spec B might have. Then the only advantage it has are the diffs, but you're still 240lbs lighter.

spec.b is not 240 lbs heavier than nonltd. On paper, subaru may state this, but it is not the case. Mine weighed in at 3335lbs in stock form. I was dead even with a nonltd at the strip. 240lbs is a serious difference, enough to show up on dragtimes, but that isn't the case.

Been talking to a local subaru autoxer before i buy (the guy that got be into autocross) and he said that I should get a WRX instead due to the fact that the VF52 turbo'd motor in the 09+ can be tuned to pretty much STI power and he says WRX insurance is not bad. He suggested I ask you guys about the VF54 from the '10 legacy and if I can make similar power with that, he has no experience with that turbo, in case I ever intend to go to SP. Right now with my 350z I am in BSP so yes I intend to do this since I enjoy SP.

 

I'm curious about this. I wont be getting a 10+ legacy because I hate the way they look but since I autocross this is something I need to think about.

 

In autocross turbo swaps are not allowed unless its in the same model line, you can update/backdate from there. I guess its "allowed" but you would be in modified, which is something that would suck lol.

 

I'll probably end up getting a legacy regardless since I like this car but I figure i'd ask this question since its something i'm going to run into. Weighing my options

In street prepared (where you'd have a tune on the car), the 09 WRX goes into BSP with the STIs, where the Legacy goes into ESP. You can only back/forward date items like the turbo if they are just a direct replacement, that definitely does not apply in the case of the 5th gen to 4th gen Legacy.

 

Swapping to a VF52 will throw you immediately into SM, which is a playground you don't want to be in on a turbo like the VF52. ESP is a very good class for the Legacy (personal opinion, there's no real results to back that up at National levels). Stock is probably about the only other playground you could be competitive in. STU is pretty much out since you're up against STIs, and SM you need to do a lot more work than just a drop in turbo.

In Ontario, Canada, a mildly modified Legacy (mine) is in the same class (ST2) as an 09 WRX 265, also lightly modified (sways, cans, Cobb AP with OTS map, Federal RS595R tires) and he's not only kicking my ass to the tune of 4% better times, he's making headway into the top 10 over all. More power, lighter weight, better tires.

 

If you want better potential with less effort, get the rex. If you want the leggy, it's more work, but there are things you can do.

Are those SCCA rules? If so, the classing is really odd, and the AP is not allowed in ST. Plenty of STI and WRX guys run them illegally, but the rules are quite clear. You go to street prepared when you modify boost controls.

Our rules are based on SCCA rules, but aren't exactly the same. Boost controls can be modified, either physically or electronically. We're trying to accomodate more of the 'run what you brung' crowd that are new to the sport.

 

That is the part of the point of the ST classes, no? You got bring 'em in before you can get 'em hooked.

Been talking to a local subaru autoxer before i buy (the guy that got be into autocross) and he said that I should get a WRX instead due to the fact that the VF52 turbo'd motor in the 09+ can be tuned to pretty much STI power and he says WRX insurance is not bad. He suggested I ask you guys about the VF54 from the '10 legacy and if I can make similar power with that, he has no experience with that turbo, in case I ever intend to go to SP. Right now with my 350z I am in BSP so yes I intend to do this since I enjoy SP.

 

I'm curious about this. I wont be getting a 10+ legacy because I hate the way they look but since I autocross this is something I need to think about.

 

In autocross turbo swaps are not allowed unless its in the same model line, you can update/backdate from there. I guess its "allowed" but you would be in modified, which is something that would suck lol.

 

I'll probably end up getting a legacy regardless since I like this car but I figure i'd ask this question since its something i'm going to run into. Weighing my options

 

The VF 54 is not a direct bolt on to BP/BL GT (4th gen). The necessary updates to your car to bring it up to '10 spec aren't going to happen, but if you went to that style turbo setup you'd be in SM.

 

Also, the VF40/46 is a better autox turbo than the VF52. The 40/46 doesn't have the top end of the 52, but they spool quicker.

 

stage 1 VF40 LGT: http://efilogics.com/dyno/graph.php?gb=0&hp=1&torque=1&rpm=1&sl=1&sln=1&runid1=156&rgb1=000000255

 

tuned VF52 on an otherwise stock LGT: http://efilogics.com/dyno/graph.php?gb=0&hp=1&torque=1&rpm=1&sl=1&sln=1&runid1=1157&rgb1=000000255

^ Throw a new downpipe on and that changes pretty drastically though.

The VF 54 is not a direct bolt on to BP/BL GT (4th gen). The necessary updates to your car to bring it up to '10 spec aren't going to happen, but if you went to that style turbo setup you'd be in SM.

 

Also, the VF40/46 is a better autox turbo than the VF52. The 40/46 doesn't have the top end of the 52, but they spool quicker.

 

stage 1 VF40 LGT: http://efilogics.com/dyno/graph.php?gb=0&hp=1&torque=1&rpm=1&sl=1&sln=1&runid1=156&rgb1=000000255

 

tuned VF52 on an otherwise stock LGT: http://efilogics.com/dyno/graph.php?gb=0&hp=1&torque=1&rpm=1&sl=1&sln=1&runid1=1157&rgb1=000000255

Nice, good to know that the stock turbo is better anyways.

 

In street prepared (where you'd have a tune on the car), the 09 WRX goes into BSP with the STIs, where the Legacy goes into ESP. You can only back/forward date items like the turbo if they are just a direct replacement, that definitely does not apply in the case of the 5th gen to 4th gen Legacy.

K, I was confused about the concept of updating and assumed that since they were in the same line (05-11 is the years mentioned for legacy in the rules) that I could use the newer. If its not an improvement its a mute point anyways was just curious about this.

 

As far as having the tune the car that is the one of many reasons why I want to go from 350z to this type of car I like the idea that I can do a stg1 or stg2 tune with just buying a downpipe and get good performance increases. On the Z in BSP I do well but after plenum spacer you don't get much of a bump from anything unless you spend a comparably obscene amount of money. I do well with this car but like I said I need something with 4 seats now on top of that.

 

Thx for all this info.

SM is the reason I still own and auto-x my Toyota Celica... Not that I'm taking any trophies home anyways, but I feel I can compete better in ST than I could in SM with the LGT.

The 4th gen lgt is a great ESP car. the LGT would be in STU, not STS, against STIs. STU is not a good place for the Lgt since you cant increase boost or upgrade diffs and the lgt has a weight/power/grip disadvantage when compared to a STi. ESP separates the LGT from the sti and allows you to essentially make a sti out of the lgt by allowing boost and diff upgrades. and the PAX is pretty good too. Ive done very well with my LGT, but its pretty well prepared for the class.