New Build

[xcarguy]

Isotope Green Birkin :driving:

[locost7018]

Yep, that's green! Where are you located and how long before she is on the road? What motor are you going to use? Russ

[11Budlite]

I'm guessing by the widetrack front suspension and what looks to be an exhaust cutout on the passenger side that it's a later Birkin set up for a Duratec?? It's looking pretty nice so far!

[xcarguy]

Engine will be a 2.0 Duratec using a 2.3 FRPP head, Crower Stage II cams and Rotrex supercharger. Hopefully on the road by early spring 2011. Located in AR.

[Croc]

Ooooh! Nice! Engine specs sound excellent.

 

Did you spec it with the Birkin IRS?

[xcarguy]

Thanks for the nice comments. Yes, spec'd w/ an IRS. Uising a Subaru Forester LSD diff w/ 4.11 gears.

[WestTexasS2K]

Sounds like it will beca fun car. I don't know if the R160 diff will hold up to the supercharger. We used the same diff on our first supercharged car we were making about 300 rwhp. We had to change the 5 times in one week with broken pinion and ring gears. You may want to consider cryo treating your diff parts to help strengthen th some. Or change to the R180 out of the STI Impreza. You may also find the first few gears will have slot of wheel spin. We changed to 3.90 which works good with the lower end grunt of the Rotrex. You will love Rotrex power is very linear the unit is very quite. Are doing air/air or air/water intercooling? Sounds a great project and a lot of fun. I like the color too it looks good with black wheels.

[locost7018]

Whoa there, xcarguy, Arkansas? You know there is a Midwest Se7ens Gathering in Harrison, Ar this coming June don't you? Do you think she will be ready by then? We sure would like to see it there. Even if she is not done you can still come up and be with the group. Right now we have about 12-15 cars going to be there. Hope to see you there. Russ

[xcarguy]

WestTexasS2K,

Thanks for the heads-up on the R160; I'll definitely keep this in mind. Is the Impreza diff the same ‘dimensionally’ as the Forester (axles were ordered for the Forester diff--still learning here)? Also, what year Impreza? As for power, I won't be making quite the RWHP with this car as you are; w/ air-to-air intercooler and a modest 7 pounds of boost, the engine should net somewhere in the neighborhood of 270-280HP at the flywheel, so the Forester unit may be feasible for my application. In addition to that, my engine has a stock bottom end, so I don’t really think I want to boost beyond 7. Still, the R180 unit may be a good investment for down-the-road mods. I’ve been in the car hobby (mainly building) since my teenage years, but I’ve been a diehard V8 guy . . . that was until I discovered just how much fun the Seven style cars are. My last build was a supercharged Stalker. Still, as I said, I’m learning hear and I’ll take all the input I can get.

BTW, I gather from your forum name you own one of Brian Anderrson's designs. He and my late father-in-law served in the Army together in the 60's.

locost7018,

I did not know that. But I would love to attend!!! What are the dates and details? I have an ex room mate living in Harrison. He pastors the Fellwoship Bible Church.

[jbanker]

Hey Shane,

 

Glad to hear that you are back into the car building business. Keep us posted on your progress.

 

Jack in Indy

[locost7018]

It is June 9-12. Host hotel is The Hub Motel about 7 miles south of Harrison. 4 Days of blats, autoX, and se7ens. You won't be dissapointed. Go to LocostUSA and do a search on Midwest Se7ens Gathering 2011 or email me at trialsman@kc.rr.com and I'll put you on the notification list. The list of attendees is growing each day. Russ

[xcarguy]

Jack,

Thanks. Great to hear from you!!! I’ve had a three year hiatus from car building with my job change, move, etc. I haven’t posted on the Stalker Group forum in a while, but I still poke my head in every now and then. It’s nice to see that Mike is coming along nicely with #85. And it looks like the Stalker guys are picking up the pace a bit with the LS series engines.

Russ,

Thanks for the dates. I’ll research and email. The 122th will be on my birthday . . . my 50th. Man, I’m getting old. :smilielol5:

[xcarguy]

Should of read 'the 12th'

[locost7018]

Xcarguy I here typing mistakes are a sign of getting old. You are a youngster if your only 49 1/2. Russ

[xcarguy]

I'll take that as a much needed compliment. It's just that I'm now the old dog at work and every year the world seems to look a little younger. Typing mistakes and spad belling (HA!) are truly a sign of of getting older. But I still have my sense of humor.

[WestTexasS2K]

Xcarguy the R180 is dimensionally the same. The ring gear section is bigger but they should interchange The axles will be different for sure the STI is heavier. We change the center section, axles and rear uprights.

 

I am the new owner of World Class Motorsports. I bought it from Brian a few months ago.

[JohnK]

Xcarguy the R180 is dimensionally the same. The ring gear section is bigger but they should interchange The axles will be different for sure the STI is heavier. We change the center section, axles and rear uprights.

 

I am the new owner of World Class Motorsports. I bought it from Brian a few months ago.

 

WestTexasS2K,

These are timely comments re the Subaru rear ends - My kit came with a 3.5455, mechanical LSD diff :-( , so I'd like to swap it out with an LSD closer to a 4.11. Any guidelines for getting all the parts / models correct along with identifying the model(s) I should be after? I have inboard brakes so I sure don't want to have to change axles.

[xcarguy]

WestTexasS2K,

 

Thanks again for the diff input. Going to stick with the R160 since I'm already geared up for it (no pun intneded) with my current axles. I knew Brian had sold WCM, but I didn't know to whom; congratulations! BTW, I had a chance to drive Goldie a few years ago, do you happen to know where that car is now? Just curious.

[WestTexasS2K]

JohnK most Subaru's share the same diff if it is an all wheel drive version. Impreza WRX, Forester are the most common. They come with a variety of gear ratios 3:54 3:90, 4:11 and 4:44. For naturally aspirated engines especially the S2000 engine the 4:11 or 4:44 are the best. If you do more track days and less driving on the road the 4:44 certainly gives you alot of grunt out of the turns. It will rev to about 4200 at 70 mph which can become a little annoying on long drives at steady state speed. It doesnt bother the motor but the engine noise at the level can wear you down after 200-300 miles.

Millenium Auto speacilizes in Subaru salvage they are very knowledgeable about the diffs. http://www.y2kimports.com/contact-us .

 

Chuck Spera has a 4:11 diff with Quaife diff in it that he is intrested in selling. He will be in Michigan thru Christmas after that he will be in Florida for a few months so if you are interested let me know fairly soon I dont know how much he wants for it.

 

I have a few diffs here I have one brand new in the box that is an LSD but I dont know the ratio. I have about 10 others but I need to pull the covers all of them and get the ratios.

 

General rule of thumb on Subie diffs if the diff cover bolts are gold cadium plating they are limited slip. If they are plain steel bolts they are open. I also have a chart that I will try to attach. I have it for about 10 years so it is a little dated I think it stopped in 03 but it will give you an idea of ratios and LSD and which car has what.

 

With your inboard brake setup your axles should go into any of the R160 diffs that accept axles. Some diff have a stub axle that comes out of the diff those wont work.

[JohnK]

WestTexasS2K,

Thanks very much for the complete data. I, and I'm sure all the other Ultralite owners out there , am/are happy to have this info.