All,

Here is my dilema... I own a 06 MR and I am getting my 1/4 messed up because I either have to shift to 5th gear or increase the rev lim to croos the final line.

I ordered some GSC S1's for the car and was looking to get the BR Springs to be able to raise the rev lim.... right now at ~7800. I think that I need only 500 RPMs to cross the final line but certainly do not feel comfortable to raise the rev lim to there w/o upgraded valvetrain.

Any suggestions on what will be a safe number to set the rev lim? Any other suggested mods to been able to accomplish the final goal w/o having to swap gears/Final Drive in the tranny?

 

I am not sure what BR springs are, but if it is valve train such as springs and retainers then you should be fine. I personally would use supertech, but I am sure if Buschur makes a spring and retainer it is probably tested before to make sure it can keep your valves from floating or dropping at high rpm.

 

Oooops! By that I refer to the Buschur Racing Custom Dual Springs and retainers.

The actual product can be found in here: https://secure.buschurracing.com/cat...products_id=38

 

just raise it to 8500 even if you dont go that high its there incase.....you wont hurt anything anyway......especially if you do springs and retainers.

 

The stock springs and retainers are pretty stout, 8500 may be pushing it, but 7800 to 8000 should be fine. I would personally wait to get springs and retainers for piece of mind though lol

 

Actually, I shift gears around 7000 RPMs depending on gear and only would like to cross the final line at 1/4 track w/o having to shift to 5th gear.

I am getting better in shifting to 5th but still I am better off not using it! Thanks for the advise!

 

Only trapping 110.6 I wouldnt bother shifting into 5th. It doesnt seem to become a problem till 113.5+ or so in my experience. Crossing the big end 8K+ is where it kind of can be iffy. In my MR I am seeing over 8000 actually crossing the line which is always a higher speed than the trap plus the fact that no one I know lets off exactly at the 1320 mark.

Once the weather gets better and I feel going to the track will be worthwhile here in the NW, I will post logs with proof of RPM in 4th at a given trap speed. Joe, I am curious how you get consistent shifts into 5th with your 6 speed? Mine seems to like to lock me out to the point where I am never sure if its going to be worth it to try. I hate running 12.11 @ 108.1 cause I couldnt get that last gear and coast the traps.

 

the buschur racing dual springs & retainer are good to 9k + . that info provided to me from a pm from David himself. i have orderd a set myself but have not installed them yet waitin to get the Buschur secret camshaft set. those springs are actually supertech spring/ retainers, i guess Buschur spec cause they came packaged in supertech packaging

 

I know on my stock setup my 5 speed trap 8200rpms at 125 each time and 121 was 8000rpm.
Right now we were testing 9000rpm and the aem said 142mph

 

Thanks for the input Paul. The problem is VIII 5 speeds are different than even IX 5 speeds let alone the MR box. MR's are lower geared than the 5 speed and have a low geared 4th on top of it. I think Lucas is gonna get a visit so I can get a clutch.