hello there I need some help on this mystery that has been killing me for couple of months.

here is the vehicle mods.

95 ford f150 xlt
302 v8 (maf)
4r70w(1,5xx miles since rebuilt)explorer oe high stall, sonnax sure cure kit and sonnax pressure boost valve.
e7te heads (valve job and machined for comp cams 987-16 or 986-16 don't remember which part number.
comp cams 35-349-8 cam.
mustang shorty headers,no cats,2in 2out muffler side exit in front of wheel.
3:73 posi from an explorer 235/75/15
3" drop beams upfront
flip kit and drop hanger 7" rear drop.

sorry if it's confusing typing from phone.

so here is my story. took off heads and dropped em off at the machine shop. got them back 2 days later by then I had everything prepped. so I installed heads torqued to proper specs and sequence and torque angles (new head bolts). got the top end back together and proceeded to initial start up. everything was fine adjusted the timing and tightened down the dizzy. I then let it idle waiting for the lifters to charge up. to my disbelief I had rocker/lifter noise. I took off valve covers to recheck rocker arm bolts and everything was nice and tight. I ran it like that for a couple of days then checked rocker again. cyl 6exhaust and 7intake push rods too short. how can this be ??? when the rest of the 14 valves have preload and everything while on 6 and 7 I can wiggle the pushrod up and down with rocker arm fully torqued. I swapped rocker arms,channel,push rod from other bank and the play stays on cylinder 6 and 7. no preload on base circle at all. so did the machinist cut the valve stem too short?


I am by far an engine guru but i have and old timer passing down some knowledge and took me under his wing. this just has me growing grey hair.

so I have the intake off while I am contemplating on 1.7 crane roller rockers or proform pedestal mount rockers. I believe in U get what u pay for but I have no prior experience with finding correct pushrod length.

can anyone point me in the right direction with the play on those 2 valves?? also are the proform even worth considering?


I went with that come as a recommendation from conanski.

boy I can feel it pull all across the rpm range good torque 2,500-3500 is the sweet spot on my truck


if I am not making sense please let me know so that I may elaborate. thank you

also since I'm running stock rockers I am assuming im @.512 stock rockers
rockers by what comp cams says. and I know they list that cam as needing 1.7 ratio rockers to be at .544 lift?

 

Check the lifters on those cylinders and make sure they are pumping up. If not you have an oiling issue. Or bad lifters. The machine shop would have really had to grind a lot off to make them stay loose.

 

I swapped lifters too maybe I should make a video

 

I'd suspect a couple valves on one of your cylinder heads has been mis cut, and the easiest solution now would be a couple custom pushrods.

 

so to achieve that Paul I am in need of a PR length checker; which would you recommend?

I was told the CC works just fine. if I decide to go with the 1.7 crane pedestal rockers the other 14 PRs should theoretically work, I would only have to check the two valves that I am having issues with? or should I check for proper length on all regardless.
i shouldn't bother doing a witess mark check since I can see the play.

 

You paid good money to have those heads reworked I would take them back to the shop to have them gone over again. If they "missed" checking the valve installed height on two cylinders what else did they screw up?

If you want to give them a bye then you need to check every length IMHO just to make sure there are no other easter eggs in your basket. Skipping the witness mark check is another recipe for disaster.

 

I was referring to the witness mark on the two valves in question. I will do the witness mark check when I install the 1.7 roller rockers. Well I am going to go by the machinist and see what he has to say later on today.

 

well I spoke to him he said to check it with a straight edge and they are "true" .... I dint know what to do anymore

 

You need a pushrod length checker. A good tool to have in the arsenal....and will likely shed light on your problem, that way you don't have to rely on others (i.e. machine shop). Once you find the problem yourself, the machine shop has no choice but to fix it.

 

Have you checked the cam to see if you may have a couple cam lobes that went south after you started the "fresh" engine? What oil did you use? Did you do a proper cam "break-in procedure"?

 

engine was not "fresh" just heads. as far as break in procedure I was under the impression roller cams didn't need break in. I stuck an oil primer in the dizzy hole and spun it counter clockwise with drill.

zr1 10-30. coated every lobe with Lucas assembly lube I can see the lobes thru valley. engine runs good other than the slack in 2 valves. I highly doubt the cam is bad but I can't rule it out at the moment and I am not trying.g to pull out cam

 

Guess I thought this was a fresh build with a flat tappet cam… I guess I'd look at the lifters at this point.

 

update: ordered crane energized 1.7 ratio roller rockers.


Idk why comp cam shows both of these cams as 264hr.

I have this cam 35-349-8 while looking up specs I confused it with 35-320-8. well I know the 35-320-8 is meant to be used with 1.7 rocker ratio.

I should be able to use the crane rockers with the 35-349-8 without issues. what is the formula to figure the new lift with the 1.7 roller rockers?

they arrive Wednesday or Thursday the latest.



should I run the 1.7s or $240 better spent.t somewhere else??

 

Here is my cam specifics.
Comp Cam Data Sheet
Part Number: 35-349-8 Grind Number: XE264HR
Lifter Type: Hydraulic Roller Lifter Engine Type: FORD 5.0 (1982-2001)
RPM Range: 1500 to 5500 Valve Timing : 0.006
Lobe-Center Angle 114 Intake Center Line: 110

Intake Exhaust
Valve Lash: Hyd. Hyd.
Duration: 264 270
Duration @ .006" Lift: 212 218
Valve Lift: 0.512 0.512
Lobe Lift: 0.321 0.321

Valve Timing @ 0.05" Lift: Open Close
Intake: 22 BTDC 62 ABDC
Exhaust: 73 BBDC 17 ATDC

 

I should be able to use the crane rockers with the 35-349-8 without issues. what is the formula to figure the new lift with the 1.7 roller rockers?

Lobe lift x 1.7 , in this case .321 x 1.7 = .5457 = valve lift , the question might be did the machinist install springs and setup that would allow this amount of lift safely ?