morrisg wrote:How about another shot in the dark? The EGR is exposed to the boost? Ok, it's supposed to flow exhaust gas back into the intake, but what if it's leaking boost inlet air into the exhaust? Can you block it off or use a clamp to close off the hose to test this? You should be able to feel 15% more power so you might not need a dyno for this test.
Hi, morris:
I hope that, when the engine is warm, the EGR valve will be closed and prevent my "leakdown test" pressure from bleeding off into the exhaust. The only part of the EGR I know of which is exposed on the 2L motor is a stainless tube which runs from the extreme rear of the block to the extreme rear of the blower case. There's no way to block it without removing the blower. And that's what I intend to save for the very last step.
Moto Mike the calibrator on this project said I shouldn't go back for another $75 dyno session until I started having traction problems. At this stage, traction problems from 200-plus Hp would be sweet.
If you pressurize the intake on a static motor what you will find is a big leak, as one set of intakes will be open. Sounds like you still have the stock pipe from the header to the muffler I would make sure that is not your problem especially if it a flow problem. I would also open the air filter air box and make sure nothing is blocked before the air filter
elloco54 wrote:If you pressurize the intake on a static motor what you will find is a big leak, as one set of intakes will be open. Sounds like you still have the stock pipe from the header to the muffler I would make sure that is not your problem especially if it a flow problem. I would also open the air filter air box and make sure nothing is blocked before the air filter
Hey:
You're right about the valves. I've been concentrating so much on the SC, I just dropped the internals out of the equation. Duh!
Intake path is clear -- first thing checked. Exhaust pipe comes off tomorrow. Not holding my breath, though.
I've been tinkering around in the background for a while with the help of Brian, my calibrator Moto Mike. Eventually even Magnuson, which built the blower kit, even got on board. Cosworth dropped off the scope because they really didn't know anything about the innards or functioning of the blower. They just marketed the thing. They ducked and dodged and blamed my calibrator for a couple of weeks without ever admitting they were out of their depth. When it all came down to my very specific questions about exactly how to inspect/test the bypass, they just quit answering my emails. Enough said.
Brian and Moto Mike up at MotoEast have continued, very patiently and without fail, to help me work through this. My premise has been that I did a really careful install and didn't want to tear it all down (and risk screwing up the REinstall) until I checked everything I could from the outside -- and it turns out, there was a lot to check. You folks have a lot of imagination. Now, all that has been done and I don't mind pulling down my work.
Brian has talked to Magnuson and they have agreed to bench test the blower for me. Didn't sound like they really liked the idea, but they may realize this could be a learning experience for them as well. They said the blower was designed to make only seven lbs and couldn't believe I was keeping my NC together at 8.5. Shows everyone can learn a little something if they keep their ears and eyes open.
Over the next week or two, I will pull the blower off and ship it to them for testing. I'm also planning to send in the idlers, since I've got a squeak at startup that sounds way too bad to ever get well. I have not been able to pin down the squeak to the idlers or the front end of the blower, even by using a stethoscope.
I will post again when there is any news. In the meantime, here's what I think is one of the most valuable lessons I have learned: DO NOT make a big change in a motor without spending the bucks to do a dyno pull BEFORE the change. If I had confirmed I had a sound motor BEFORE I installed the blower, it would have saved me a lot of time and trouble over the past couple of months running down stuff I could have/should have checked before the blower went on.
Thanks to all of you for all your time and interest,
Fred
Just to keep everyone posted -- the blower's on the floor in the garage. It came off a lot easier than it went on: four hours instead of eighty. Starting tomorrow, I'll be waiting for an RMA from Magnuson so I can return it (at my expense, of course) for testing.
When I pulled the blower off, I found all the manifold bolts still tight. All hoses and connections were exactly as they should be. The metal manifold gasket was completely and uniformly flattened. I could see the outline of the gasket on the mating surfaces of both intake and head, completely around every port without a break. At the time of the install, the inside of the intake ports of the head were already stained by air/fuel mixture. Today, the inside of the intake runners of the blower were stained by the air fuel mixture from running since the install. But there was no staining on the mating surfaces of either the manifold or head indicating where the air fuel mixture leaked. Long and short of it -- It wasn't the install.
What sort of guage are you using? Can you set up an air pressure test, using a air source, with a regulator setup, like one used with a paint gun. I was told I had a vacuum leak, but it seemed odd I had 18" of vacuum (measured with a digital boost/pressure guage), so I decided to plug the exhaust with 2 tennis ball, plugged off the lines to the EGR, brake booster, purge valve, and intoduced air pressure, keeping it around 3 psi. Found the leak, the so called liquid gasket that was supposed to seal the joint between the intake ell and sc body, didn't seal, solution, a gasket. Hope you fix it, having a "lame" SC is no fun at all.
