So I ended up meeting the guy I raced the morning of the night I hit the curb. We talked and BS'd for a while and I told him the story about why I did the swap and how it had been tried by many but completed by none.

Recap on the race. We started from a roll at like 10 mph... With the 6-speed that put me right in the torque of the V8 in 1st. I was stupid and mashed instead of rolled into it and spun 1st and 2nd. He was car lengths in front of me. 3rd I reeled him in and 4th I was pulling on him.

We had a small run up to 70 ish when I saw him a couple days ago. Had I started a little better it would have been me in the lead for the most part but we were pretty even. Obviously 1st off the bat he has me beat every time.

He told me about his STi and said he has 40K invested including the price of the car . He said he is 300+ to the wheels.

Well he wanted to tell the people on his forum about me and the car and this is what was said:
Would you drive this car? - Socal Subaru Forum For SoCal Subaru Enthusiasts: SoCalSubies.com

He didn't quite understand that I was dealing more with firmware and immobilizer BS than tuning, that I was running a stock 5.0L tune, but that's ok. He's a real cool guy.

He also said he would buy my car if I sold it lol, and that he should be the first to know lol. That was also right after I told him I would sell around the $30K mark if I did ever sell it, which I wont .

 

I used to have a glorified Vega with a SBC, four speed, and posi. Turned out in autocrossing it was faster from a dead stop starting in second. I did have to replace the clutch periodically but got very good at it.

CF seems to have a similar issue, a first gear that is too low to be useful and you lose time in the shift. With a rolling start even more so particularly if you have a stock steel flywheel (inertia).

If you have an Android smart phone and Torque, you can measure time to distance which is what you are really concerned about and see for yourself which is faster. Suspect you would be surprised.

 

For drag, in theory with our gearing setup, we are faster in acceleration than we would be with a lower final drive or starting in another gear. Using 1st, technically we should be faster. I hate it, and from rolls for now on I would start in second at low speed but from a stop, it's easier on the clutch and quite a bit quicker.

I'll make a video of launches and the difference between starting in first and second. It's night and day. Even if I pick the revs up and launch in second with a good slip to get going quick, first is still a lot quicker. I think that's why I can sort of keep up so well with this AWD monster on launch. My only problem with first though is traction. Since the V8 is still somewhat new to me, getting the whole 'roll into the throttle' idea down to perfection is difficult, and the 275's aren't helping much lol. When I go with aftermarket rims I'm going with 295's or 305's in the back.

Some new info just hit yesterday with flywheel's so stay tuned. There may be an option to move to a Solid flywheel rather than the Dual Mass which would cut the inertia a lot.

 

Don't need wider, just a better tire... Unless you want that wide backend look...

 

I'm sure better tires would help, the one's I have on now were just a throw on for now kind of thing. As far as look, I'm pretty happy with the 275's.

 

With as little weight as there is over the rear axle, I'd be hesitant to increase the patch too much; the effective friction just won't be there. 305mm may just be that number.

 

Yeah, all I have in the trunk are my subs, I think it ends up being 60-70lbs. Each time I ran with this guy I had a full tank as well.

You're saying 305 might be the number where the effective friction isn't there? Or 305 may be a good size to try out?

 

Any time you have issues with traction in a front engine rear drive vehicle it is a matter of weight transfer.

Also if you had to rely on friction, no 1/4 mile could be faster than 9 seconds. What you need are wide sticky (why there are burnouts) tires to use fractal surfaces to exceed 1 gee. Slicks used very low pressures (wrinkle wall) to maximize the contact patch on launch and were like an extra gear as they grew at speed. What I have found works best is a rim width just about the same as the tread width to keep the tread flat.

This is why back in the day before really good tires (and breakouts which destroys the whole purpose of a race) you jacked the rear end and used 90/10 shocks so that when accelerating the car would be level, and a slider clutch (before the Ramchargers made automagics popular) to transfer the weight back.

A characteristic of a really fast car was that it seemed to raise straight up when what was really going on was that the slappers were pushing up on the body and down on the axle.

However an IRS (like a Corvette or Jag) is different. The diff is bolted to the body so it does not wind. In this case you start with everything lifted so inertial forces are loading the rear end. Lowering is great unless you are in a drag race.

Just some thoughts but physics have not changed, just tires have gotten much better

 

Too bad we can't just crank up the old "Torsion Bars" like they did 50 years ago.

This is what "Grip, Grip's" car should look like when he gets it sorted out next year.

 

Every time I see one of Jim's runs, I am watching the front stretch.....but, last time I saw a video of Anthony's run...he is stretching the front suspension too. I have to try and come out harder next spring...my 1500 rpms starts need to increase to 1800. My problem is running a street tire class.. You can only push them so far...

 

Tough call, really comes down to the compound. If I had to guess, 305 is probably toeing the line. Worse still is if your tire has a stiffer sidewall vs stock.

Given any thought to your next tire?

 

I think in a year or so I'll be setup with a second set of wheels for something like this. Right now I'm looking to be as quick as possible with street tires.

Lmao. Anthony and Jim are crazy! I'm waiting for that post though, 'first wheelie at the track today'. lol

That's the one thing I like about having a clutch. I can soften the launch a bit with slip. The only thing that sucks is getting enough slip to be quick but not sit and roast or come out too slow.

A little but for the next year or so I'll probably be on cheap used sets, I burn through them too quickly to buy new right now. I am giving thought to slowly collecting a drag setup over time, but I haven't thought details yet.

 

The only difference between that AMX and Jim and Anthony's cars is a bigger set of slicks and some 4.88's.
Hang time for the Crossfire's front wheels are getting closer every day.

 

On the street I run 285's (Michelin PS3's - all season) and they're good for at least a 3.8 second 0-60. This isn't theory, as I ran it the other day with a small nitrous shot. They also hold a 4.0 and 3.9 without spray very consistently.

The point is that tire width doesn't mean everything. As for the track, 1.5 sixty footers are pretty common for me with the 265's (MT ET Streets) I'm using.

I also had great success with 255's at the track (Hoosiers) and on the street (Michelin PS2's - all season). WIth the 255 Michelins I'd see 4.2 0-60 with only a machined pulley, tune, and NW single.

I was once very close to widening my wheels in order to fit 315's, but I'm glad I never went through with it.

 

Gee the same 0-60 as a '65 Pontiac 8*).

The point is that how well the tire is balanced to the car/wheel, how sticky the compound, and how well you can hook up is more important than tire width.

BTW was that 3.07 an axle ratio ? If so where did it come from please ?

 

I know, I can feel it! lol

Nice Anthony! Exactly what I was looking for. I think 285's would be a good street setup for the rears. Ill look into those tires too.

3.07 is the diff from the auto's. NA and SRT.

 

That's news to me. I thought 3.07 was SRT6 only, and that 3.27 was the NA Crossfire (both 6 speed and auto).

 

I haven't actually researched it, I just assumed from all the auto talk of 3.07's. lol.

 

So for a TCU change from 3.07 to 3.27 you could just get one from an auto NA xfire? hmm. Interesting lol. Why did I never realize the NA and SRT's had different diff's?lol

 

Got me, but maybe. Definitely worth a try I suppose.