Backfire problem on RX1

[MartyRX1]

Hey everyone, I've got an RX1 w/Bender II turbo. This thing backfires like hell when I get her above 6000RPM. Did some tests and narowed it done to #2 cyl. Checked carbs & spark O.K. Can't find vaccum leak. Could it be internal (rocker,valve, spring). It's got me baffled and could use some advise before I go any further.

Thanx
Marty

 

[Oak Hill]

Hi Marty and welcome to the site. You may be better off posting this question in the Turbo Section. There are some very knowlegable guys, that should be able to help you with your issue.

 

[Tork]

Welcome to TY and I'll move it where you will get the best turbo help.

 

[lakercr]

Hi Marty,

Start withthe obvious stuff. How have you sealed the T's that pressurize your float lines?

 

[Skydog]

Its not TORS is it??

 

[Anonymous]

Are you running rich?

I had same problem and it happened with timing too retarded and being too rich.

 

[Mr Cool]

Are you running rich?

I had same problem and it happened with timing too retarded and being too rich.

Jep... I think its running too rich , but be carefylly.

 

[MartyRX1]

Backfire problem

I don't think the problem is turbo related. It's coming from cyl #2. If timing was off, our running too rich wouldn't it affect all cyls??? I've checked all the obvious and not sure were to go next.

 

[Skydog]

Swap coils? Swap plugs?

 

[rxrider]

If you are absolute sure cylinder #2 is causing the problem, do a compression or/and leakdown test. You may have a leaking valve putting unburnt charge into the exhaust. Just a thought.

 

[MartyRX1]

Backfire problem

Changed the plugs,Swaped coils,checked compression.It's all been done.

 

[Thomas800]

Are you sure on the tee's. I had ours sealed up ready well. Ran a half a year, but then one split on the bottom seam between the carbs where you couldn't see it. We chased a bad miss on what we thought was #2 cylinder only to find the tee. This is after completely tearing the top end off looking(valves out too). We had also changed the complete ignition looking. Try some really soapy water and compressed air on the pitot line.

 

[MartyRX1]

Backfire problem

I'll give that a look and see.

 

[MartyRX1]

Backfire Problem

When you guys talk about the tee's I'm assuming you're talking about the small ones at the front of the carbs. Blew air through them and no apparent leaks. How many PSI's should these take and whats the best way to seal them. Mine are held in by tie wraps. Is there a simple test I can do to find out if that's the problem?

 

[Travis Moore]

Re: Backfire Problem

When you guys talk about the tee's I'm assuming you're talking about the small ones at the front of the carbs. Blew air through them and no apparent leaks. How many PSI's should these take and whats the best way to seal them. Mine are held in by tie wraps. Is there a simple test I can do to find out if that's the problem?

Sounds like you found them. The best way to seal them is simply order the billet ones from MPI. One of the most important parts of a forced induction install on a RX1.