I'm running a 265/35r18, so stock height. I'm going to to have 255/40r17 for autocross though. It's what I ran all last year in the stock trans and turbo with E85. It was fine. The local courses are fairly tight.

I still have my stock final drive, so going back doesn't really cost me anything. I'm running all the other gears are stock Evo 8 ratios. I don't feel the 9 first is that big of a deal for autocross. The guys with 9's here in Vegas still don't use it on course even though it's a bit taller.

I think the 4.30 FD would be perfect for a 94mm stroker with a turbo making full boost at 3800ish and 500whp and 450 or more torque. So basically, my current setup, but a stroker with the bottom of the power band 500rpm to the left. That's an expirement I'll probably do at some point.

I'm really hoping the stock final drive livens the car up enough for autocross because I really like the red everywhere else..

 

I made the mistake of going with a Red as well, have not even had it on long enough for a single oil change.

Some of the stop lights around me are so short that the Red can't get the car moving quick enough with stop and go traffic. Could only imagine trying to pull out of a hairpin with it haha. I too used to autox and will be switching to the Green and get back on course again hopefully soon.

 

Damn I don't think the red is THAT laggy, u kinda make it seem like 6262 lol.



letsgetthisdone -- so your ditching your red setup so fast? booooooo

 

It's not THAT bad. If I didn't autocross, it would be the perfect turbo with the final drive. And it might even be OK for autocross when I go back to the stock final drive, so we'll see.


It's not that laggy, it's just laggy enough with the 4.11 final drive. I'm going to put the stock final drive back in and go from there going to that sometime within the next few weeekends. I may just build a 2.3L after talking to Aaron about it. He said with the twinscroll housing, I'll see peak boost 500-700rpm faster. And it'll still rev out to 8k. Problem with going that route is I'll need another clutch. The act xtss won't hold 500+wtq. And exedy twins aren't cheap.. :/. Where as a built 2.0L and 71hta or bbk full will put me with 20whp of where I am now, with proabably a little more torque. And the current clutch will be fine.

 

I have a video (GoPro) of one my runs last year, Stock FD, FP Red, 2.2L. No noticeable downsides coming from a Stock FD, Evo 9, 2.0L.

 

I have high hopes after seeing this video

 

I may want to do some Autocross with my Red. I think on a 2.3 and higher compression it will be fine. On a 2.0, well, yeah, it might seem a little laggy.

 

If the local stuff is tight then you may need all the gear you can get. Its just a weekend to swap out the FD and press the gears off the shafts. Just check the clearances with the current FD in it and note them. John at TRE is a wizard so he has them set up well. Might not be a bad idea to have some extra shims beforehand.

I'm with you on the 94mm experiment

I'm going to be trying something gear related within a few days. I'll let you know how it turns out.

 

I actually assembled my trans. I sent Jon the shafts and center diff. He sent me shims and solder and walked me through setting it up right. So yea, I know it's easy to change final drive. Not something I would want to be swapping all the time though. Local courses are generally all second gear.

What I would be up for doing is purchasing a 71hta, and swapping turbos for AutoX. That's only a 3 hour job...lol

 

It doesn't hit 300tq until 4300-4400rpm, and 30psi around the same. Without a stroker it is hard to get it moving right away if you are not going to ride the clutch as you take off. I'm talking about the SS housing though.

Do you really want to go to something as small as the 71? The Green in MHI form feels great in comparison to the Red in MHI, opinion of course.

 

The 71 may be a knee jerk reaction lol. I'm going to try the red with stock final drive and go from there. The Green does pick up about 300-400rpm in boost threshold from what I can tell. My car gets 300ftlbs right at about 4k on the charts in the first post. So a little faster than the SS housing.

 

Never downsize your turbo, just upsize your engine. Strokers rock.

 

One aspect I'll toss into this discussion is that IMHO the anti-surge cover does affect transient response negatively. I've had the BBK, BBK-3B, and HTA Green on my Evo all with essentially the same supporting hardware, and hands down the BBKs have better for transient response. The main benefit of the antisurge cover is to make for more predictable response when leveling off the throttle or releasing slightly under part throttle steady or decreasing boost conditions. The Green shined there because it could bleed off pressure effectively on the the charge side.

 

I think the FAP cover effects off boost response, and maybe boost threshold. But transient with this thing is amazing. Response between shifts is about .2-.3 of a second to get back to full boost, and that's with out using nlts. Picking the throttle up on corner exit, boost comes on very quickly if the motor is above boost threshold RPM. If it didn't have the FAP cover, part throttle lift would be a nightmare. It already flutters the BOV a bit if you're rolling out of the throttle, or backing off slightly, mid corner. Not enough to upset the car, but it does do it.

 

Since you're apparently pretty quick with wrench, I think it it would be interesting if you got your hands on a standard (non-surge) cover for the Red and compared for yourself.