I talked to some tuning friends of mine and they thought the dyno chart looked like valve float. I’m going to re-measure for pushrods. I wonder if my pushrods are too long and hanging the valves open under power.

That would makes sense as to why the power falls off so early. I’m not sure if that explains why it makes torque so far out though.

 

In my experience valve float has more to do with springs not keeping things in check and/or pushrods flexing than pushrod length.

 

I was able to get in the garage for an hour tonight and I measured the pushrods. They are the proper length. With a pushrod length checker, I get around .035" of lifter preload. I checked both valves on a couple cylinders.

The hotside is air tight. I just fabbed up the hotside and checked it on install, but you might be on the right track. Next on my list of things to check is to see if my flex pipes have blown out in the inside. Maybe the exhaust is so restricted the engine just can't breathe. I also checked to make sure the cam is installed dot to dot, it is. I did not degree the cam when I installed it though, just dot to dot.

I'm going to be in the garage working on it tomorrow evening. Look forward to more updates.

 

I’d say we found what the engine was fighting. The hotside is 2.25” pipe so with the flexpipes blown out like this, this makes them what, 1.5” pipe? I’m going to get these cut out and fix it with something better. Hopefully that’s the entire issue.

 

Bingo found the issue. Cant wait to see more power!

 

Back pressure must be massive lol.

 

Ugh o. She gonna wake up now. I no longer use flex joints. Too many failures.

 

Well on the bright side, I proved you can make 800hp to the tire through a 1” hotside!

 

Chokasaurus!!!

 

Looks like some ******* put two ******** in your pipe

 

Great find! Interesting, the dyno curves look like a PD blower and nothing like the boost curve.

 

You mean a centrifugal.

 

Just use the proper parts, vibrant makes multiple flex’s intended for turbo applications, they have solid liners vs the inner braided crap like most others.

 

Been there! Wont ever use that braided style again.

 

Way off topic, but I always chuckle at your name, because:

SLOW SEDAN
8 second club

cracks me up

 

I’ve never had issues with the braided flexpipes on my other hot sides I’ve made. However, those were pump gas T4 turbo setups that don’t make a bunch of power. Lesson learned.

I’m going to a no prep race at an airstrip this weekend so hopefully I can borrow someone’s draggy and get some data.

I just fixed the hotside last night and the car would barely idle in open loop because the fueling changed so much. I can’t wait to drive it.

 

One of the many reasons I don't ever use flexpipes unless the turbo is mounted to the chassis itself and not the engine.

 

Just to follow up. I went to the track last weekend and all I can say is wow. It definitely woke the car up. When the exhaust was plugged, I could run 28lbs of boost without running out of fuel pump. Now, it’s out of fuel pump at 21-22 lbs of boost. So it’s safe to say it’s making a lot more power on a lot lower boost levels. I don’t think I’m going to take it back to the dyno anytime soon, but I’m really happy I figured out the issue! Thanks guys!