Hey guys new here, I recently built my first tpi engine and am having a problem. The engines runs very rough and has no power. The only thing I have found that I think might be a problem is the vacuunm of the engine. It only has 6 hg at idle and has 45lbs of fuel pressure. Isn't that way to low of vacuum and to high of fuel pressure? I'm thinking the low vacuum is causing the high fuel pressure. And if so what could it be, because all vacuum lines are good and in the correct places. Intake crack? Or what if the cam is off a few degrees would that kill the vacuum?

mild comp cam 264H

Thanks

 

The 45lbs is fine, but the 6" of vacuum is not. Yes if the cam is installed wrong it will cause that. Did you degree the cam when you installed it?

 

No. And the whole cam install has got me confused now. I don't know why some people say put the gears dot to dot and some say both at 12 o'clock when your at TDC on the compression stroke. I always thought it was dot to dot, even the comp cams intructions say put it like that and have a picture of it like that. I installed the cam and crank gear with both dots at 12 o'clock. I now have the engine back apart and am ready to do it right because this has to be the problem. I just can't believe it's running that far off. I will appreciate anyones guidance on this cam set up. Thanks.

 

Setting the cam Dot to Dot places the #1 cylinder at TDC on the exhaust stroke. Cranking the engine over one turn puts the crank dot back at 12 O'clock and the cam dot at 12 O'clock as well ( cam turns at half speed of the crank) This is now TDC on the compression stroke. You can install it either way, but going Dot to Dot is usually more accurate.

 

Thanks a lot buddy. That's what I needed to hear.

 

Thanks guys, that's what it was I had the cam 90 degrees off. I started it just for a minute with the timing chain cover off and seems like it runs great now. Thanks again.