Please help!! Missing over 50rwhp after G5X3/LSX intake install! Dyno graph inside.
03-07-2004, 12:00 AM
#41
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Originally Posted by 66ImpalaLT1
I dont think its simply the YT's, the problem started at almost 4000rpm. Its worth trying the stock rockers because its an easy swap.
03-07-2004, 12:01 AM
#42
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I definitely don't think the YTs will fix his overall problem with the graph. I was specfically talking about how hard/quickly his power falls off past 6400 rpms.
03-07-2004, 02:45 AM
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verbs, are running stock location wires? If I remember correctly, I ohmed my stock wires and they were all between 85-98, your seem much higher so I thought maybe your using relocated, longer wires. Curious.
03-07-2004, 03:44 AM
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Originally Posted by Jason99T/A
Trust me Matt, put the stock rockers back on. 
03-07-2004, 08:22 AM
#45
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Originally Posted by CAT3
verbs, are running stock location wires? If I remember correctly, I ohmed my stock wires and they were all between 85-98, your seem much higher so I thought maybe your using relocated, longer wires. Curious.
03-07-2004, 08:53 AM
#46
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Originally Posted by verbs
I can't hear any clicking sounds. I don't see how .004 preload can be too little since that is what Comp specifies as proper preload (.002-.004 preload is preferred).
I think GM says that the preload should be in the .030 range +/- .010. I think you might be off by a decimal place. (.020 to .040 might be what comp said). I put together a motor that was underloaded and it did exactly what your was doing. lucky for me ramchargers could get me custom pushrods in 24 hours at the local store. See if you can put a feeler gauge between the top of the vale and the rocker - you can use that to see how much more length you need.
Good Luck!
-Geoff
03-07-2004, 11:15 AM
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Originally Posted by INTMD8
Looks like knock to me. (possibly getting knock and the knock sensors aren't detecting it).
96SS- Single turbo 6 speed
-774rwhp 774rwtq-
-774rwhp 774rwtq-
are those actual dyno numbers???
03-07-2004, 11:19 AM
#50
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Originally Posted by SSOnYourSix
ive been telling him that for 5 weeks now... But no one listens to me till its too late
03-07-2004, 11:27 AM
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Originally Posted by 2000Blackout
Why should we listen to you,what do you know!
03-07-2004, 04:13 PM
#53
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for some reason I thought comp said .010 preload for Comp Rs. I could be mistaken...
Also Swap on a set of stock wires as well. Have heard of lots of problems with the wires you are running.
Also Swap on a set of stock wires as well. Have heard of lots of problems with the wires you are running.
03-07-2004, 04:26 PM
#55
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I did a H/C swap on a 5.0 mustang about a year ago and the dyno look almost exactly the same. I worked on the car and trouble shot if for a LONG time before finally pulling the heads back off the car. I checked the heads and found out that they had been milled .050. The guy that supplied the heads said they were stock deck height, so I used stock length pushrods and non adjustable pushrods on the combo. After reinstalling the heads, using shorter pushrods and shimming the rockers slightly, the power was there and they dyno graph looked perfect. The heads being milled so much on his car made the preload too much when the lifters were pumped up and it was holding the valves open. After compensating for too much preload, the car ran perfectly.
btw.. I'm still running YT's on my car. I don't think they are any better than the stockers, but after spending that much money on them.. I can't make myself take them off.
btw.. I'm still running YT's on my car. I don't think they are any better than the stockers, but after spending that much money on them.. I can't make myself take them off.
Last edited by gomer; 03-07-2004 at 04:44 PM.
03-07-2004, 06:02 PM
#57
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I'd swap the MAF, see what happens, if that does not help you need to make a more comprehensive checklist of things to check.
The anti-Y/T rocker comments are pretty offbase. They are just rockers. They really great actually, I have a set.
I also have R lifters and mine are about .010 preload. Comp reccomends very little preload for these lifters. I think you can run more preload than that with these and it won't make a difference I think you might want to check to see if you are getting knock like Intmd8 said or your MAF is dirty.
The anti-Y/T rocker comments are pretty offbase. They are just rockers. They really great actually, I have a set.
I also have R lifters and mine are about .010 preload. Comp reccomends very little preload for these lifters. I think you can run more preload than that with these and it won't make a difference I think you might want to check to see if you are getting knock like Intmd8 said or your MAF is dirty.
03-08-2004, 03:15 AM
#60
First off, junk those YT's. I just put a set of those on my buddy's heads/cam a couple of weeks ago and the new dyno graph looked like ****......kinda like yours actually They are a WASTE of money IMO....Stock rockers work just fine and don't fatigue springs...
Was a new valvejob cut on the heads after replacing the valves?
They are a WASTE of money IMO....Stock rockers work just fine and don't fatigue springs...Was a new valvejob cut on the heads after replacing the valves?