Power lagging

[350runner]

Good deal...

Sent from the dust in front of you!

 

[firebane]

Also on a side note.. I have found that the idle mixture passages don't provide enough adjustment when you put in a bigger cam on the quadrajets. Right now my idle mixture screws on my quadrajet make LITTLE difference in vacuum readings when I screw them in or out.

 

[Joe383]

^Had the same problem with an old Rochester once. Could not lean it out for the life of me.

 

[MadOgre]

Also on a side note.. I have found that the idle mixture passages don't provide enough adjustment when you put in a bigger cam on the quadrajets. Right now my idle mixture screws on my quadrajet make LITTLE difference in vacuum readings when I screw them in or out.

That's because Q-jets need to be professionally modified to run big cams with them. That's probably one of the main reasons guys go with an after market carb.

 

[MadOgre]

good deal...

Sent from the dust in front of you!

xx2

 

[MadOgre]

I would start at the distributor and adjust your base timing with your car idling around 750 RPM and the vacuum to the distributor disconnected and plugged at the carburetor. Adjust your timing to get the highest vacuum reading. Next adjust your idle mixture screws tell you get the highest reading and go back and check timing again. My car back fired a few times when I first got it together and it was not enough timing. I am running lean too so have to replace my jets also. If you cant get a better vacuum reading then do a compression check of all cylinders and make sure you did not flatten a cam lobe. I do my valve adjustments with the motor running on hydraulic flat tappets. I back them off tell hey start to clatter than turn them 1/2 past were they get quiet. Don't ever do that to a roller motor though. Your cam card should give a ball park of were your vacuum should be and I would expect at least 15" After you get the motor running at the highest vacuum you can drive the truck for a few days and check plugs to see if your running lean or not.

A flat lobe will not cause compression issues. it will cause combustion issues though.

You should never, ever, adjust valve lash like that! NEVER! EVER!

The motor needs to be shut off. and each valve being adjusted needs to be in a fully closed position(You will need to rotate the crank shaft to be able to adjust all 16 valves) Then you back off the rocker arm. Then you tighten the rocker and at the same time spinning the push rod in your fingers. When you tighten the rocker to the point that the push rod stops spinning freely, then, you tighten down the rocker nut an additional 3/4 turn.

This is the only way to properly adjust valve lash!

Sorry if I sound rude, but I must clarify that the old wives tail of adjusting valve lash while the engine is running came from a drunk guy who lived in a trailer park named Bubbles.

But seriously no ill will intended.

 

[350runner]

^^^[emoji23] [emoji23] [emoji23] [emoji23] this is spot on...
Damn that bubbles LMAO![emoji23] [emoji23] [emoji23]

Sent from the dust in front of you!

 

[Brandon777]

I will try a compression check and I'll check all the plugs, I just don't get how driving feels normal with no problems but my vacuum level was low

 

[350runner]

Compression could be a factor. I've got different vacuum readings from two different carbs.... That might be it right there. The carb. If it runs good give that carb time to break in. This requires some drive time. It'll let them gaskets swell and seal.

Sent from the dust in front of you!

 

[Brandon777]

Okay, yea it could just be the carb I'll give it some time. But I'll check compression still

 

[350runner]

Good deal.

Sent from the dust in front of you!

 

[Joe383]

I have not broke a motor yet. Raced for 3 years, have had a lot of hot rods. Some of the things I do are back yard mechanic but it works just fine. Don't bother with the clips they make for the rockers though if you have a lot of lift. Try to adjust valves with motor running and clips fling off. Cut top off a tall valve cover to keep oil from splashing every were. You try to adjust a motor with roller lifters this way and you explode the lifters. Doing it with a hydraulic flat tappet is just fine.

 

[chengny]

Sorry if I sound rude, but I must clarify that the old wives tail of adjusting valve lash while the engine is running came from a drunk guy who lived in a trailer park named Bubbles.

F*** Bubbles - that was my idea!

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[350runner]

Lmao!

Sent from the dust in front of you!

 

[MadOgre]

Sorry if I sound rude, but I must clarify that the old wives tail of adjusting valve lash while the engine is running came from a drunk guy who lived in a trailer park named Bubbles.

F*** Bubbles - that was my idea!

You must be registered for see images attach

Freak man! You really crack me up sometimes LMAO !!!