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Top Swap Info and Faqs, Also lots of 3800 Info



Ok... when I took my UIM of my 2000 for the topend swap there was a LARGE dia hose coming out of it. I think it is called Evac. According to some GTP Diagrams this goes to the 3rd (closest to the firewall) vacume tree. Is there an adaptor or part I need to connect the to? Or can some one who has pics of the top swap post them.

And one tree goes to the bypass and the other to nothing or "atmosphere" correct?

Thanks

-KT
 
The large diameter hose is for your brake booster. You can get a brake booster hose from an L67, or I think you can just make it work.

The middle of the tree is for the vac line for the HVAC system, it's the smaller hose that's connected right next to that big one mentioned earlier.
 
How rough should the motor be when you first start it before it adapts and gets use to boost?
 
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pontiackid said:
How rough should the motor be when you first start it before it adapts and gets use to boost?
Click to expand...

You need a new tune. End of story. It can't "adapt" enough if you try to use the same PCM. The best way to do it is start with a L67 file and change it to work with your trans. Then tune fueling and spark as needed to keep it from blowing up.

Mine chattered a little bit as the lifters got pumped up, but even the first start on mine and ever since was perfectly smooth. Runs as good as it did when it rolled off the assembly line if not better.
 
I know I need a tune. I guess my problem is in the MAF... (idles when not pluged in and will die when pluged in) I'm not showing any boost (even when reved up) on the DIC and I am showing 15ish VAC on my mechanical gauge. Couldn't find any Vac. leaks either...
 
Yes, I am using a GTP file and a 67 MAP.

My digital DIC is showing no boost periord. Though my mechanical Autometer gauge is holding at 15psi VAC and after I reved up, I am hitting 20-22 VAC.

We hooked it up to an HPtuner and my MAF is still giving me a reading but, is way off. When it is connected/plugged back in it will kill the car.

About the MAF it is my old 2000 one, just put it on a 67 TB.
 
You probably need a new MAF. If you're getting no boost I'd look to make sure the BBV is operating properly and not stuck open.
 




So I've been reading up on this, and I'm very interested in doing it, but has anything thrown out an approx/avg cost involved in doing this? I have an 04 grand prix gt that I'd love to do a top swap on, just looking for a little better idea of the money involved before commiting to something... as all mods are based on budgets. haha
 
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