39 FCR & Exhaust?

[Turbo B]

I am new to this site. The information that I have gathered here in the last couple of weeks has been great. I have contacted Scott at Sparks racing about the 39 FCR carb. He says that I should go with the X-6 exhaust with the 39 FCR. I agree, but I just bought a used Big Gun Race series slip on REAL cheap. The quad is totally stock otherwise. My question is, will the stock head pipe be no good with the FCR carb & Big Gun slip-on? Should I just get the exhaust header that goes with the Big Gun and use that set-up with the FCR? By the way great review Maryland 400EX on the FCR, you got me sold. Keihin should have you on payroll!

[jb400exxx]

the stock headers mos people say are good enough. i have the T-4 slip on and i want to get a cam and 11:1 piston and the 39 fcr and i'm still gonna stick with the stock headers.

[Turbo B]

I've heard the same thing in regards to the stock header. I am just leary on bolting up the FCR and being disappointed that the exhaust header is too restrictive. I don't know, maybe the slip-on that I already have will be enough to let the motor breathe with the FCR. Anyone else?

[jb400exxx]

try it like it is and if you don't like it get new headers or the x-6 system.

[Maryland 400EX]

Thanks Turbo B... You know, there may be other pipe and carb combos that work well for the 400 EX, but that is something that I'll never know. As for you installing the carb with the stock header, sure it will work but the headpipes on the stock header are a bit smaller and may be the bottleneck in your quest to make power. You need to get the X-6 so you can utilize the larger diameter head pipes and free flowing muffler for better exhaust flow. The Sparks X-6 Pipe gave me enough midrange power and torque that I was thinking back to the phone conversations with Sparks and Carb Parts Warehouse who both said the FCR 39MM gives an even bigger increase than the pipe. If that was true, I was going to be one very happy guy. I was thinking as I was riding that I was going to order the 39MM FCR as soon as I got home. And that's what I did. Now I've got the Pipe & Carb installed but haven't really ridden that far yet because of X-MAS and all but in the short blasts I've made down the driveway I was truly impressed. The quad is much stronger everywhere and the throttle response is amazing. With that said, I'm now looking into the Sparks 416 piston kit and the Sparks Aggresive Cam. I would just do the cam first, but I don't think it will work as effectively with the stock 9:1 Compression as it would with the 12.5:1 piston. So, that's next on my to do list. I have access to race gas (Close to home) so I'll be using the high compression piston for max power with the smallish 416 piston to keep the heat problems at a minimum. Go for the Sparks X-6 and 39MM FCR, you'll be happy you didn't shortcut.

[HOT-ROD]

i like both mods

[crashinmatt]

ive been told that the fcr is better suited with full-system, but as for now i am usin the stock head pipe and a slip-on with my fcr. no matter what u do, the fcr will make a huge improvement. so, if u want to save a bit of money for the time bein, just get the carb and use the pipe u r usin. but would look into eventually gettin a full system for best power.

[Turbo B]

Thanks for the replies, guys. I appreciate the insight. Anyone else have any ideas about the carb and exhaust combo?

[Dave400ex]

I also agree that it would be best to have a Full Pipe if you get the 39MM FCR. Think about it, the FCR is allowing way more air in then the Stock Carb, so you need that bigger Pipe to make sure all the Air can get back out quick too.
Maryland, Are you going to get the Drop-In Cam? If you do make sure you get Valve Springs and a new Cam Chain too. X-Rider can tell you all about that. Better now then spending to fix a screwed up motor. The Sparks clutch kit wouldn't be a bad idea either.

[MR. HONDA EX'S]

Dude get the FCR!!! It's going to be the best bang for the buck. The stock head pipe will work fine with your big gun. But down the road get a better slip-on and grind the welds in the ead pipe, or just get a full system (yosih is a nice, nice system, wink, wink)!
Get the carb, do it man. Everybody is!!

Later

[440ex kid]

I would get the full Sparks system. The Big Gun full system has a lot of bends in the header unlike the Sparks pipe.