Lets me start off by saying I hate working on cars... i really really do. They are a total buzz kill Other then that I love them to death

So my problem now is I have no vacuum... I've tried the carb cleaner spay on everything and no change to the engine idle at all. The VAFC is reading positive both when at idle and at 3-4k (yeah I have a Power FC ecu, but the vafc is soldered in and zeroed out... plus the big read out on the vafc makes it easy to see the map pressure).

My question is, since the head is shaved 25 thou and I have spec b's with the cam gears at zero, could I be getting blow by that is causing positive manifold pressure?

Craig - Who really does love working on cars... except when the brakes don't work due to no vacuum to the booster

 

Also I can breath in both direction through the PCV valve so I'll be replacing that. However, I did take it out of the loop for a little while trying to see if that was the main cause for the lack of vacuum, but it wasn't.

 

May I ask just where you've got a MAP sensor on that setup?

I'd say give "D" a call.

 

I called D and he said it is possible...

As for the map sensor, it is hooked up to the vacuum log via a block of aluminum channels machined into it. I check the map/block/hose combination with a vacuum pump and it hold vacuum, so thats not the problem.

The fuel pressure reg holds vacuum also

 

Yeah, I hate working on cars too!

Good luck.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zygspeed &raquo;</TD></TR><TR><TD CLASS="quote">Good luck. </TD></TR></TABLE>

Thanks...

You making to expo this year?

Craig - Who might be tracking the m if the r isn't fixed

 

Nice way of telling us you're boosted now.

 

hahaha... i wish that was the cause

 

have you checked the brake booster check valve?

 

iirc, a shaved head effectively causes retard to both cams. there's a formula floating around somewhere, or people like cheetah and donf have it in their brains... so you can ask them.

i wish i could help, but i've only seen pressure during wot and only during a brief portion of the powerband when I was NA.

 

Check your valve lash...

 

I also bought leak down tester so I'll be checking that out also.

 

positive pressure FTW .... except in this case

Buttchange.... see you at VIR bro

 

Well after advancing both cams 5 degrees I gained some vacuum at idle, but once I start going, its goes back to positive pressure. And any time I hit the brakes it goes to positive pressure.

I'm going to check the valve lash again and see if maybe that is off.

Craig - whos is trying to narrow this pos down

 

I don't know, looks like you have an invisible forced induction setup, I would be happy with that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hypeR speed &raquo;</TD></TR><TR><TD CLASS="quote">have you checked the brake booster check valve?</TD></TR></TABLE>

Or is the valve turned the correct way? Thats what it sounds like.

 

I haven't checked the valve, but yes, its in the correct direction. The arrow points to the vacuum mani.

 

Check the valve. I shaved my block by 0.026" and I have vacuum.

 

fwiw my na setup also generates positive pressure at certain rpms, around .1 to .2 kpa

 

I checked the valve and it is correct and working. I also checked the vacuum reading on the Power FC compared to the VAFC and the VAFC was showing pressure while the Power FC was showing vacuum.

So after talking to Brad @ RLZ and Jack, we think it has to do with vacuum nipples in the itb runners not being big enough and the eagle vacuum manifold not having enough volume. So Brad is going to make me a big vacuum log today and I'm going to put bigger nipples on the runners. Hopefully that will clear it up and this pos will start running better.

Craig - Who hopes to get it tuned this weekend if all goes well.

 

Bigger Nipples FTW!!!!

See ya this weekend Fawker!

Let's do Chetahs again.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dave_B &raquo;</TD></TR><TR><TD CLASS="quote">Bigger Nipples FTW!!!!</TD></TR></TABLE>

Beat me to it you bitch

Buttcoin, you coming to Exblo?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Splat &raquo;</TD></TR><TR><TD CLASS="quote">Buttcoin, you coming to Exblo?</TD></TR></TABLE>

Hell yeah... However, I am not sure what I'll be driving

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AssPenny &raquo;</TD></TR><TR><TD CLASS="quote">

Hell yeah... However, I am not sure what I'll be driving </TD></TR></TABLE>

Track the loaner Xterra

 

haha.... that thing blew donkey *****...

It'll either be the arrrrr or the lead sled