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Boring out cross over tubes

1.1K views 10 replies 6 participants last post by  99grinder  
#1 ·
I know it's been said that the .085 stock cross over tubes are plenty but my brother is boring them out to .097 on a lathe and I was wondering whatthe procedure is or if anybody has done this before?
 
#2 ·
Curious why so large? Why not get .093 tubes? Haven't seen anyone do it before but I'd imagine just get the tubes to run as true as possible and get a carbide tip or full carbide drill bit and bore them out use some cutting oil as you go. I suggested carbide drill because not sure how hard the tubes are and you don't want to snap off a bit in the tube or it might be ruined. I've heard the bigger .093 lines will make your engine run Alil rough wonder how his will be let us know how it turns out for him curious myself if it effects anything.
 
#3 ·
damn well a few things here...unless he's running a big VP44 like a monster pump or dragon flow there isn't much need for bigger tubes. also i've heard that guys actually lose HP with the .093 tubes do to a drop in injection pressure.(unless running large pumps) .093 typically make your truck have a lope and can sometimes even have a slight bucking lower in the throttle.
 
#4 ·
What's your brother have for mods? If its stock, it's gonna run like crap. No gain whatsoever with even a moderately modded truck. And like stated before, will probably lose HP.


Sent from my iPhone using AutoGuide.com Free App and fat fingers... So expect a bunch of misrakes.
 
#5 ·
It's my truck lol sorry for the confusion I'm moving to dragon pump and 6x.018 injectors. And I'm having them bored to .097 because it's either .097 or .125 and .125 is massive
 
#6 ·
just drill them out. use a slightly larger drill to remove the edge filter first. might wanna do some research on the dragon flow pump. they are not know for their reliability and II is know for denying warranty.
 
#8 ·
Well my tubes say 085 on then I assumed it was stock size I've heard in the past they were .085
 
#9 ·
I called my brother today and asked him not to bore them. Just remOve the filters. I took into consideration what Kraft said and I'd rather just leave them stock size. I'll see how it runs with the 6x.018's once I get my head back from o-ringing. I'll post pics of the tubes when I get them back
 
#10 ·
Good man!! i think the dragon asks for .093 and i wouldn't go any bigger than those. Try yours first with the filter drilled out and see what you think. easier to go bigger later than it is to go smaller later lol.
 
#11 ·
Yeah that's what I figured so I'll see how she runs when I put the motor back together