Have a cat, sounds like you need one.

 

Haaaa!

What cat were you guys running? I have a vague memory of you guys running a long tube header mated to the GWR exhaust with the cat in the midpipe? That's my setup as well. Will be good to know if I should expect to fry the supplied cat once the turbo goes in lol

 

I don't think it's anything wrong with the cat. The tune wasn't great and we believe that's the reason for the dead cat.

 

Hooker header, GWR proto catted, resonated midpipe, RB twin tip muffler. Not the midpipes fault. Bad tune like Ed said.

 

So, experimental tune, trying to ascertain the limits of the engine?

Sounds like curiosity killed the cat.

 

Not necessarily experimental. BBR, the company that builds the rotrex kit, has a lot of time into their proprietary tune to get good driveability. It is valuable IP. We pulled the restrictor, added Flex Fuel and needed to run bigger injectors. So we needed to retune but they would not unlock their base map for us to work with. So we had to build our base map from scratch and it is, well, imperfect. Ran great when on the way back from the dyno so we thought we were going to be okay. But it got progressively worse as we drove it. Perhaps long-term fuel trim, maybe fried O2 sensor. We have not diagnosed it yet.

 

Ooo, I think that's me in the passenger seat on more smush Thanks for the ride, a very potent experience even if power was down. Sorry about the cat, I guess if you put me and Sonny in the same vehicle something is bound to fail.

 

Yeah, this is one case where I can understand a locked tune. It sucks for you, but given the purpose of this tune and the productization, it makes sense.

I started to noodle on what could be causing this, but then I realized that would be like a preschooler giving tips to a neurosurgeon.

I wanted to come up to the Reunion to say hi, but I figured you'd all be crazy busy with your hordes of adoring fans. Far easier to harass y'all on here and make my bad jokes electronically. I'm a bit jealous that @sonofthehill got to ride with you! My back is preventing me from doing things like that right now, here's hoping I can get that sorted before next season.

 

Did compression test albeit with throttle closed. ~170psi on cold engine. A bit low but all were the same. We'll reload the original map from the dyno tuning session. If that doesn't work, we'll put the restrictor and 550 injectors from the kit back in with the BBR tune. Hopefully
that and some datalogging will reveal something. It ran so bitchin after the dyno, we want it back!

 

 

You forgot my pear picture



Also, Carlos @sonofthehill

 

All hail Carlos. Saved our ***. Welder to the rescue!

 

Looks like we got most of it with the hammer/chisel Ed! So close.

 

There was an impressive chunk stuck in the muffler. It made enough back pressure to blow the midpipe apart at the slip joint.

This was my first experience with trying to knock out a metal core cat. I hope it is the last. This was not what I was hoping for when we decided to bring it to the track with the cat in it.

Thanks for all the help, Carlos and curly.

 

Sorry brother. I should have taken your advice to put the catless mid pipe in for the track. Lesson learned.

 

Just glad I could help some.
I had fun hanging out with you guys all weekend.

 

Any updates on this monster?

 

Motor getting repaired. Diamond washer slipped under Rotrex blower loads. Guessing 15-20hp to drive it at peak rpm. Bent every valve and dinged pistons. So getting +2.5 and +2.0 oversize valves and a bit of port cleanup. Cams and crank getting keyed. We'll try again. We only stopped on the dyno because a coolant hose under the IM sliced open. So we were doing runs with bent valves I think. Guessing we'll finally hit some good numbers with the extra head flow, valves that seal and timing locked down. We'll see.

 

Damn, thanks for the update. Those non keyed cam/cranks always freaked me out, though I never considered this. Wonder if backpressure on that clogged cat contributed some how.

 

Damn, bummer to hear about the engine but glad you guys are still at it. I always wondered if the non-keyed crank/cams had a power limit. The turbo guys don't seem to have issues with them but I never considered how the belt load from the SC might affect the equation.

The lack of ability to access anything under the stock IM without removing it sucks lol.