Autoscope

I love the C63 and I love that RX7 just a tad bit more! My good buddy has a LS6 RX7 Track car! It is identical to yours, wheels, rear diffuser, RED, seats......It is NO-JOKE! 2800lbs, with a vette motor! I am curious to see a Renntech C63 againist your RX7! Cars look great!!!

Hedge-Hog

Thx. I'm guessing the DOM 4-pt cage adds a bunch of weight. And I added a lot of custom SS bits that can't be light. The 2929lbs was at an SCCA Nat Tour weigh-in so I think it was accurate. I also did it with 3/4+ tank of fuel as I have major fuel starvation on left turns with this setup. I've since ordered a tank baffle but haven't bother with it yet.


Your friend has great taste! Thx to you as well. A C63 (oem or modded) should take the FD on a roll since I'm so laggy. My friend's 996GT3 easily beats me off the line in autox but when I am on boost and can carry speed in turns, I get him back. Mine you, my driving sucks so it's prolly a non-issue.

mthis

i love the c63 but that rx-7 is just insain.

Autoscope

What kind off power does your RX7 have? Have you thought about doing the LSX swap? I will find some pics of my buddies for you! He has over 400/400 at the wheels with 4.11's.....It's crazy fun!

Yellow R1

He mentioned he has 425 rwhp earlier.

You can get over 500 rwhp with a bigger turbo (ie a T-78) which is quite a bit (or get a bigger turbo & put over 600 rwhp). Rotaries put out as much exhaust as V10 Viper allowing significant power gains via the exhaust pushing turbos....you just have to ensure adequate fuel is added or you will pop the motor (12,000 lbs/Sq inch will break just about anything - including the apex seals which you break with 2 fingers). Not adding fuel is the Cardinal Sin for people unfamiliar with rotaries (then they call the engine a POS when they didn't get the car properly tuned - oh well). Although I will say Mazda should have put silicone hoses (not rubber) for the turbo hoses & a bigger radiator (which all rotary guys do) to ensure no boost issues occur nor running to warm when you turn up the boost.

Doing LSx swaps is a little silly IMO (per above - add fuel & boost & the cars run the same or more power depending on boost level). It's a major job & significant effort for no real power gain (I've got 405 rwhp on the little stock twins = zero lag & the car is pretty sprite).

Anyway - I like Hedge's set up. His FD looks great & is well maintained. Glad to see another rotary/Benz guy. Cool!

-Matt

Autoscope

Wow thanks for the info! I believe the LS6 power band is more ideal for Road racing compared to the Turbo set up! My buddy took his 500+ turbo set up out and sold to fund his LS6 build. The LS6 swap is actually not that hard compared to other retro-fit engine swaps. I'll put it do you this way, he is not a Tech and he put the motor in........

Either way, the car is looks great and I'm sure it drives great!

anjay

my 09 c63 gonna come this month
im so excite lol
by the way one of my friend tuned a FD3S that goes to 600 HP
is very nice in the pic too

Yellow R1

Turbo rotaries have broader power bands than a 2V V8 (8k redlines & beyond for 12A & 13B rotaries...higher if properly ported & plenty of fuel). On a track, you ar living from 5-8k where the engine makes most/all of its power (this is why F1 engines have 19k redlines - the power is always on tap & has a huge/wide powerband - same as a sports bike). Cars that develop high HP (and likely less torque - especially down low) are more advantageous on a track...not so good for street applications (ie an S2000 or an RX8 are good examples of cars lacking torque - especially that N/A Renesis in the RX-8 - a serious mistake for a 4 seat car needing torque for street driving).

My SLK has ~ 560 ft/lbs at 2,000 rpm compared to my FD, which ain't too impressive that low (it gets out of its way just fine as it weighs as much as a microwave but the SLK pulls like a freight train down low). However, the SLK gets pulled upstairs as the rotary belches fire at 9,000 rpm on a 70 mph roll. Just different power plants - both are pretty fun.

-Matt

Autoscope

Good info! Wouldn't your power band depend on your Turbo size? I wounder what turbo my buddy was using, I'll have to ask! So you guys like the RX7 as a track toy?

Hedge-Hog

D'oh...been too busy to answer but it seems you guys are having a good conversation yourselves.

My FD is not fully tuned as I managed to set my boost controller trigger wire on fire during the dyno day (I forgot to heat wrap that thing ). So that day, we pulled the control hose and ran w/g spring pressure (~13psi) for boost level. I was hoping for 18psi and around 500rwhp but I may be dreaming. LOL. The GT40R turbo is quite large for a 13B-REW even bridge-ported so on point and shoot tracks, it has a distinct disadvantage. On bigger flowing tracks (like Portland), this car should be fun.

I can't comment on track FDs versus others since mine is so different from a typical FD now. I gotta say the Penske dampers are amazing. I do recall that most mildly modded FDs need to have smoother inputs for corner entry and exits. Their multi-link rear will bite you if you lift too abruptly (it causes mega toe changes). I do love how it feels...very direct and controllable. As fat as my car ended up, it's still lighter than a C6 Z06 and has about the same power...and I run r-compounds to boot. Fun, fun.

Here's my mod list: http://encompass-tech.com/photogallery/FD3S%20Spec.pdf

BTW, I am really digging the C63 as it's very pointed for a daily. There's an initial understeer feel that I need to get used to. It turns but it feels like it needs more ackerman or something.

Cheers,
-H

PS. I think your buddy will definitely have a ton of fun in the LSx. While I love that motor, I feel it defeats the spirit of owning an FD if I were to forsake the Wankel.

Yellow R1

That is an excellent (read, "kick azz") turbo & I'd get one if it weren't for the CA **** SMOG requirements. I see you had Steve tune your car - he did mine too - my brother & I have known him for ~ 10 yrs - great fella & a knowledgeable tuner.

Enjoy your C63!

-Matt