[enkeivette]

So... I found the cause of the low boost, lower hp than I expected and the excessive crankcase pressure. A leaking intake manifold gasket.

For those of you who remember, on dyno day I was only seeing 5lbs of boost while I should have been closer to 10. Also, they had to stop the second run early because I was blowing oil out of the valve covers. What was happening: my intake manifold was leaking into my lifter valley. This was causing a loss of boost. Where was the boost going you ask? My crankcase! The positive pressure was leaking out into the crankcase through the lifter valley.

So now, I'm seeing closer to 9lbs of boost. (it's hard to watch anything but the road when I put my foot in it). Like it wasn't fast enough already. On top of that, I've upped my jet size from 78s to 80s in the primary and 88s to 94s in the secondary. Still feels like the belt might be slipping up in the higher rpms, need to crank it down some more.

I wonder if the leak was affecting my AF ratio. With a vacuum leak I know it would but with a boost leak I'm not sure it's as critical, as it's blowing out air and gas rather than just sucking in extra air. And the car still has a rough acceleration in the lower rpms, I checked to make sure all of the lifters were moving, so it's not a stuck lifter. I did notice that my dist contacts were all burned up, do you guys think that could be the problem?

[enkeivette]

I thought this was an automotive forum! C'mon guys, step out of the BS lounge for a sec and tell me how great I am.

[Vettezuki]

Originally Posted by enkeivette

I thought this was an automotive forum! C'mon guys, step out of the BS lounge for a sec and tell me how great I am.

I'll tell you how great you are when you take that thing to a track and help me beat up on Fords and Imports.

Now what's your plan for traction? Your vette sounded pretty damn strong on the dyno, I wonder what it's putting down now . . . ? By certain esoteric calculations, I say 500 WHP.

[enkeivette]

Originally Posted by Vettezuki

I'll tell you how great you are when you take that thing to a track and help me beat up on Fords and Imports.

Now what's your plan for traction? Your vette sounded pretty damn strong on the dyno, I wonder what it's putting down now . . . ? By certain esoteric calculations, I say 500 WHP.

I wouldn't say 500 wheel hp. I dont see how 4 lbs of boost could account for 60-70hp. And I calculated jet size based on the boost and AF ratio that I had before. I wonder if I'm lean again, probably. I need that bloody LM1.

[Vettezuki]

Originally Posted by enkeivette

I wouldn't say 500 wheel hp. I dont see how 4 lbs of boost could account for 60-70hp. And I calculated jet size based on the boost and AF ratio that I had before. I wonder if I'm lean again, probably. I need that bloody LM1.

4 lbs is just additional pressure, depends on what your NA specific output is (and a lot of other factors), but 4lbs could easily be that much, especially combined with your port matching, etc.