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-   -   Gforce panhard and exhaust (https://www.rx7club.com/race-car-tech-103/gforce-panhard-exhaust-717484/)

Zyrano 01-01-08 04:05 PM

Gforce panhard and exhaust
 
I think I know the answer to this question, but just figure i'd double check. We just installed the gforce panhard (trilink will go in next week). but my RB SP system no longer fits in. any recommendations? I'm either going to have a exhaust shop tweak with the RB rear section, or have them built something with a magnaflow muffler. Any options out there that I'm missing?

jgrewe 01-01-08 04:10 PM

Run the exhaust under the rear end. Does he still mount the chassis end on the pass side? That's how the first ones were and we were able to have plenty of room for a three in. exhaust.

David Dewhurst 01-02-08 08:03 AM

Check out how the chassis parts would mount if you mounted the chassis parts to the drivers side of the car. Check out how the axle parts will mount to the passengers side. I understand you most likely received the parts welded together. It ain't that big a deal to get some new metal & make the chassis parts so they attach to the drivers side.

Just another thought............:icon_tup:

ps: If your racing the car when you analize the tracks you race on that's the deciding factor with which side you mount the parts to.

j9fd3s 01-02-08 10:28 AM

my last gsl-se had the old style panhard, and the RB SP system fit, although it was close

Zyrano 01-02-08 08:20 PM

Thanks for the input. The chassis end is still on the passenger side. the SP is close, but not quite there in terms of fit, we are maybe an inch off. I'll hopefully have the car in the exhaust shop next week and we'll see where to go...

hella24 01-05-08 08:21 PM

I have the g-force panhard and tri-link on my gsl-se race car. I had a racing beat exhaust that used the stock pipe over the axle. I changed the mounting brackets that go between the muffler and body and cut off the exhaust hanger near the wheel well. Now I have an old school mind train complete exhaust system that fits over the axle very well. I had to add ~ 2inches to the muffler connection. Placing the exhaust under the axle could lead to clearance issues depending on how much you lower the car and how you mount it in relation to how the axle will now move. Susko said he ran his exhaust under the axle, but I prefer the over the axle set up.

jgrewe 01-05-08 08:52 PM

As you go lower it increases the the room for exhaust under the axle and obviously decreases the room above. IIRC Improved Touring rules let you go down to 5" ride height. When you get close to that you can end up with an exhaust with a couple bends that are less than 15 degrees each. The straighter the better.

Jim and I put the panhard mount on the pass side to add weight to that rear corner. They didn't allow ballast in IT and these cars always ended up light by about 80-100lbs on the pass rear. I even filled the vertical support member with lead on mine. The other option was to use really thick wall material for the mount to make it as heavy as you could. Thats when you use the old "That's what we had laying around the shop when we made it" defense in the tech shed.

hella24 01-05-08 09:43 PM

Lowering the car does not increase room under the axle. Only smaller diameter wheels/tires would do that. It does decrease the room above the axle as you said. With my exhaust this hasn't been a problem. I agree with the straighter / fewer bends in the exhaust aspect. I guess I am just worried about my " driving in the grass" adventures. :)

jgrewe 01-05-08 09:46 PM

Your right, I was thinking of it being a straighter shot to go under when the car is lowered.

David Dewhurst 01-06-08 11:48 AM

***The straighter the better.***

After you have viewed Dave Lemon's E Production car you will no longer make this statement. Four (4) sharp 90* bends after the rear axle going to a muffler that's in the middle of the car width wise. Three 90* bends before the muffler & one 90* bend after the muffler. You know he uses a Dyno. ; )

hella24 01-06-08 01:26 PM

Having a dyno to test set-ups is the deal. Finding the tuning length/ diameter/ shape of the intake and exhaust systems to make the best power for your engine can take time. Doing things differently may just find you some more power.

jgrewe 01-06-08 01:37 PM

You can't get credit for a win if your car is black flagged for being too loud. I'd bet if he could keep it quiet enough he'd run less exhaust length and fewer bends. In EP the porting allowed makes it tough to keep these cars under sound limits.

David Dewhurst 01-07-08 07:29 PM

***I'd bet if he could keep it quiet enough he'd run less exhaust length and fewer bends.***

He did fab the bends deal because of noise & has gains with the bends per the Dyno.

***In EP the porting allowed makes it tough to keep these cars under sound limits.***

Along with the 10,000 usuable RPM the porting gives the motor.

jgrewe 01-07-08 10:38 PM

We can probably turn this into an exhaust design debate with little problem. lol I don't doubt he has plenty of power. Is his exhaust collected before the bends? I know he runs his fuel cell above the rear diff inside so that would give him room to run a long primary set-up around under the trunk area.
Very interesting.

I've seen really long exhausts work on a friends GT3 tube frame car. It was collected really short, like 11". Then dumped into a 3" that went back to the rear end, made a u turn, back to almost the fire wall, then out the back of the car. I think it totalled about 13' long. The car was quiet, and made tons of power.


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