HPI RS4 Exhaust System

[Booins]

I need to "upgrade" or change the exhaust system in my RS4. The reason being, the body covers the exhaust tube. I have noticed with this being an old RS4, the original exhaust system is not something that is very popular today. What kind of system should I be replacing this with? Does the exhaust system affect engine performance or is it simply just for looks/sound? Any shared knowledge will be appreciated.

Current Exhaust (Don't mind the super glue):

 

[Certified Mike]

I don't have an answer as far as what pipe to put on your buggy. However I can tell you for 100% sure, the pipe Def affects performance. You'll want to put in some research.
This is actually a good opportunity for you to learn about getting some more power out of your motor. If you choose to take that route anyway. I'll bet there are a few older posts in here that explain what pipes do and why if you were to search them out.

 

[Rooky78]

As far as the exhaust hitting the body... a simple fix would be a Dubro exhaust deflector. Only a couple bucks and has a handy little bend in it to point it the way you want.

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXD635&P=ML

 

[Booins]

As far as the exhaust hitting the body... a simple fix would be a Dubro exhaust deflector. Only a couple bucks and has a handy little bend in it to point it the way you want.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXD635&P=ML

Thanks for the link, I just can't believe I didn't find that on my own . This seems like a sure fix for me!

@Certified Mike, I read a good article from OS Engines' site explaining about tuned pipes. This is not something I am looking to get into with this car at least, but I never would have known what pipes are capable of .

 

[Rooky78]

It's one of those things. You know, the "why didn't I think of that" moment. Lol. Traxxas also uses them on their trucks, so, if you're in your local hobby shop, look around, you might find one even cheaper.

 

[Certified Mike]

I'm happy to hear that. This forum has some good info and despite ourselves, some very smart members. Always helpful. Glad you found an easy way out on this one too.

 

[Booins]

I had to make a minor adjustment to the location of the new exhaust tube. Instead of going straight through the hole in shock tower I had to wedge it in between the shock tower and shock. This is all because the new tube still hits the body, but just lower down on the body than the original tube. This is obviously not the intended position of the exhaust tube so I am wondering if this 90 degree bend will cause me any trouble.

 

[Certified Mike]

I guess stupid question, but why can't you notch the body a little bit to accommodate the exhaust? There are tons of cars that are cut that way direct from the manufacturers. It looks like you've got the deflector dumping low enough that it would likely even look like a real (scale) car or truck exhaust. As far as performance, as long as the tube isn't getting pinched during suspension travel and isn't restricting flow where it is run, you shouldn't have any issues with performance. It needs to be pointed down, like it appears to be, so that any fuel that blows thru your exhaust can flow out without collecting in your exhaust pipe. Run the engine with the exhaust in its current configuration, then shut it off and then too the whole car back on its rear to see if there is fuel pooling in your pipe. If it is not collecting (no fuel printout when you too it back) then I can't see any problems to speak of.

 

[Certified Mike]

***run the car and then TIP it back on its rear...***
***(no fuel POURING out when you TIP it back)
I'm sorry for the typos! I hate this new phone! It's got a different word for every 5 I type!!!

 

[Booins]

I definitely thought of how stupid the question was after I posted.. But I had nothing better to do and it was on my mind since I can not yet test the new setup as I'm waiting on more fuel. But thanks for answering.

 

[Certified Mike]

I did not mean that your question was stupid! Sorry to have come across that way... I meant that my question was stupid... The question of why you couldn't notch out the body a little... Sorry bout that!

 

[Booins]

I did not mean that your question was stupid! Sorry to have come across that way... I meant that my question was stupid... The question of why you couldn't notch out the body a little... Sorry bout that!

Well I wouldn't have blamed you if you thought my question was stupid!

 

[Certified Mike]

No stupid questions... Only stupid answers!

 

[Booins]

Adding onto my problem... The exhaust leaks! Right where my NEW gasket is, seems to be the problem area. Should I just slap some sealer on it and call it solved?

 

[IdriveSlideways]

Adding onto my problem... The exhaust leaks! Right where my NEW gasket is, seems to be the problem area. Should I just slap some sealer on it and call it solved?

Remove it and inspect the gasket for cracks. I'm assuming you're talking about the gasket between the engine and exhaust manifold. Make sure the screws holding the manifold on are evenly tightened. Don't tighten one down all at once. If you do, this will cause the screws to bind and create an uneven seal on the gasket. Have you inspected the manifold for any cracks or bends?

 

[Certified Mike]

What he said!

 

[cbaker65]

What they said!....Lol

You can also try using two gaskets ,if that helps!

 

[Booins]

Everything was in good shape so I changed out the Philips to Hexes so I could really torque it down. If it ever stops raining i'll make a test hit and let you guys know how it holds.

 

[Booins]

I ran one tank and not a single drop. But I noticed there was some white smoke coming off the top of the exhaust. Is that anything to be worried about?

 

[cbaker65]

I ran one tank and not a single drop. But I noticed there was some white smoke coming off the top of the exhaust. Is that anything to be worried about?

It may just be residue burning off ,just monitor it!
It is important that the exhaust seals so it doesn't effect the back pressure for the
fuel tank>The fuel tank rely s on the pressure from the muffler for the fuel delivery
to the carb.!