I just put a new 351W in my 86 and I had an edelbrock carb on it before then i moved up to a holley 700 i know the rough idle is because i havent got the carb dialed in but is that whats causing my oil pressure to flicker? it idles real low and the pressure gauge reads 25psi then it drops down when the truck almost dies. There is also a whistle and it feels real heavy to get it rolling. None of this happened with the edelbrock and im curious to know if the holley is to blame till it gets tuned? any ideas guys?

 

A Holley 700 sounds like it is going to over carburate it. It also sounds like you have a heck of a vacuum leak. Are you reading the oil pressure off of the factory oil pressure gauge?

 

i have a sunpro mechanical and other than the idle it runs fine it feels heavy off the line but runnin down the road driving normal its great... when i get on it it it hesitates but eventually picks up. ive check for vacum leaks but havent found any on the intake and carb area i even pulled the breather off and sprayed carb cleaner in there to see if i had a leak in the valley and it passed that test. i have no idea whether the whistle is air or mechanical. thanks for the help

 

Does it take a while for it to idle down? I am wondering if it is loading up.

 

when im drivin it no... when i put it in park after its warm it holds the idle up but not incredibly high its probably 1500 maybe even a little less... i dont have a tach but its definately below 2k. when its cold and i put it in park it sounds normal. i know its suppose to drop down when its in gear and all and vice versa. but it sounds off. either too high when its hot or too low when its cold

 

Just curious, why did you replace the carb? Was it having issues like this before?

 

Mine idles at about 900 to 1000 when in park and warm.

 

i changed out the edelbrock because it was spitting and popping when i would open it up just to get it rolling and it would die after a while just randomly so someone suggested i change the accelerator pump and i did want a bigger carb it was a 500cfm and i found a deal on the holley so i took that one. and on the top end it doesnt pop or spit like the edelbrock does it just has issues really at the low end and the top end is real close

 

Is it a used Holley? It might need a rebuild.

 

yea... i checked it and rejetted it but it had a rebuild so thats all good. my biggest concern is the oil pressure thing... if its just flickerin because the rpms are so low ill be a whole lot more comfortable with it. its still a new motor and tranny and i did all the work so im nervous and i check everything 20 times a day to make sure i dont blow it up again

 

did you plastigauge the bearings when you built it?