This problem is driving me crazy because I know I should be getting boost by at least 4k in second. By third, when there is a more load, I can get into boost but it is still slow to build and only around 8 to 10 lbs. by 6k. I have a 62-1 with a 1.15 hot side, street ported, through a 3" turbo back exhaust, controlled by a Haltech. 550's and 1600's. 45 psi fuel pressure. It feels like a rev limiter and it misses slightly while trying to get into boost above 4k. The car runs fine up to the vacuum/boost transition. I have one of Hitmans maps so I know the timing is a little conservative but not enough to make this happen. Fuel should be on the rich side but not overly so. There is nothing odd about my timing split, all injectors are almost new. It idles fine, starts fine and the engine might have 5k on it. Plugs are new BUR9EQP's. I can't figuire out why it can boost in 3rd but not 1st or second. HELP!

 

did you ever figure this out?

 

Well, I have checked just about everything. One factor may still be a wastegate sticking slightly open. More importantly, I think that I have a very mismatched manifold and turbine (divided housing, undivided manifold) AND the turbine housing size (1.15). I have ordered a .81 undivided because I have found that it is mostly a street car, I want much quicker response and I may start auto crossing again. There are people making 350 to 400 to the wheels on my set up and that is good enough for me. We will see in a week or so.

 

interesting problem.....any further improvements??

 

As a matter of fact, with the .81 housing, I now make a little boost in 1st, 8 to 10 in second, and as far as I can tell, as much as I need in third on up. Its still not instant as some experience on this forum but much better than before. In third, as I pass 10 lbs. I am loosing traction on old cold tires so I am taking it easy for now. I have a rather convoluted route of pipes (old style Greddy FMIC) that I believe is causing the bulk of the lag. A ram air V8 Trans-Am could not shake me this AM so the power is now more available and quicker to respond.