<VV> ; No turbo boost

djtcz at comcast.net djtcz at comcast.net
Fri Jun 12 10:48:54 EDT 2015

> Date: Wed, 10 Jun 2015 12:06:04 -0700 
> From: Geoff Haeger < thehaegers at gmail.com > 
> Subject: <VV> No turbo boost 
> > Hi guys, I?ve got a problem and am stumpted.............Here?s the problem: the turbo puts out little or no boost. I put one of Clarks good boost gauges on it and it reads 1-2 # boost under hard load in 3rd and 4th gears. The stock gauge pretty much shows the same thing. The engine runs fine. It has one of Grant Youngs carbs on it, and the distributor was set correctly. It has 120-130# comp 
> ssion. It runs exactly as a 145 CU engine with a 1 barrel carb should run. I put it on a chassis dyno and it?s getting 60-70 HP at the rear wheels, The torque is 110. The AF ratio is spot on at 12.5. I thought it had a bad turbo, so I bought a rebuilt one from Starr Cooke in El Cajon. His reads exactly as the original turbo did and performs the same. So It?s not the turbo. I have triple checked the exhaust system and there are no leaks! And all the piping and muffler is new. So, the only thing left is that the engine is not putting out enough exhaust pressure to run the turbo correctly and spin it up. So I am left with the thought that the wrong cam was installed when the engine was built, or the cam lobes were flatted by not using any zinc during the break-in. And I don?t know any way to check this without tearing down the engine. Do any of you agree with me? Or have any ideas I haven?t thought of? Any help would be greatly appreciated! Thanks, Geoff Haeger 


As others said, check for full throttle opening. 

My long ago experience was the exhaust system needs to be TIGHT between engine and Turbo. Not just quiet. 
Like so tight the engine will stall after a minute or 2 with a wad of shop rags held tightly over the exhaust outlet. 

Dan T 

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