Ok, I have been building 1973-79 Ford trucks for 15 years. But i am new to engine work. Engines have always been cheap and available around here so whenever I had a problem I just threw in a different engine. But recently I threw together and engine for fun with various parts I had laying around. Not really sure what to expect.

Lower end and block, cam, etc was a mid eighties carbed 460 (ran good but had 100k on it). Heads are Dove C heads that were on a built 460 that I bought from a pawn shop. This motor was amazing until at about 500 miles it blew a head gasket and bent 2 rods (motor was newly complete when I got it and the head gasket had been installed wrong) I scrapped the lower end years ago but hung onto these heads. I assembled the above block with with the above heads and threw on a wieland stealth intake and L&L fenderwell exit headers I had laying around. Also a MSD ignition box. Kind of just threw it all together to see what happens. Also threw on a edelbrock 750cfm carb i had.

Well I got it running and it runs GREAT! No smoke, no knocks, seems to have plenty of power! Starts great! BUT................ i have noise on the drivers side head. Not sure what it is. Like I said I am not an engine guy! Sounds like the rocker arms are rattling to me but i do not have a trained ear. After hearing this noise I suddenly remembered these heads are the pair of heads from the motor that blew and bent 2 rods so i began to worry this head was the one that may have been on the bent rod side and the head might have damage. I also have other good heads laying around so today I decided to put a different set of heads on. In addition, now that I know the lower end is good I decided to put in a comp cams 4x4 extreme cam that i bought earlier but since i didnt know how good this motor was going to be i was afraid to install it for the first fire up. I bought the comp cams kit with lifters, cam, timing chain, valve springs and keepers.

So today was the day to tear the heads off. But before I did that I was curious to see the difference before and after the head change so I did a compression check. The quiet side compression was 155, 155, 152, and 155. Very good I thought. Then I did the "noisey" side and got 175, 175, 168, 172. WOW i thought! I didnt expect to see numbers that high. I have never seen numbers like that on a 4-stoke before. I had see 170's on 2 stroke dirtbikes before but now on anything like this.

Is this possible? that seems like a lot of compression. Also when I removed the valve covers on both sides it seems like the quiet side pushrods all but like 2 were tight. But on the noisey side i think 2 were tight and all the rest of the pushrods were loose and slightly movable. Again I have no engine experience so pardon my theory if it sounds rediculous......... First off, what causes such high compresion? Is it possible...... that this head was "shaved" a little? I assume this causes higher compression but i really dont know. If so would i maybe need a different length pushrod set for this side?

This got me thinking maybe i need different pushrods for this side. Maybe thats why they seemed loose? But if it is "shaved" i would assume shorter pushrods would be needed. But my application with most being loose makes me think that i need longer ones. I put a wrench on the nuts on this side hoping to tighten them and make the noise go away but they seemed very tight, i know i just tightened them to spec when i assembled them. Is there maybe something else i am missing? Is it ok to run an engine with 175psi on one side and 155 on the other? This motor really ran great this morning. I assume if there was head damage it would have shown up on the comp test.

So here is my debate:
Change the heads? Or leave these on since it runs so strong and doesnt smoke or anything and just put the new cam, lifters, springs in and hope the noise goes away?

What do i do about the pushrods? Is it common to have to change the legth of the pushrods? These rods should have been the ones that came with the block, not the heads. I removed the heads years ago so I have no idea where they are to compare them?

Is there anything i can do differently when assembling? All i did originally was tighten the rocker arm nut to whatever the torgue spec was in my repair manual. I seem to remember they felt like they bottomed out but most on the noisey side still felt loose. Is that normal? I'm not sure how many should be tight and how many should be loose or if they should all be tight all the time????

The truck is tore down at work in the shop for the three day weekend. Heads are still on but intake is off and the stock cam is out. I have to have this truck out of the shop before we open tuesday. I dont know how to proceed. Any advice would be appreciated! I will be working on it tomorrow and monday but wont have access to a computer during the day when i am at the shop. My gut says just swap the heads to be safe but the motor runs so great I hate to do that if its not necessary. Also the heads I will swap with are just used heads and nothing special and I dont even know for sure they are good. But will check in before i leave and when i get home each day. Hopefully someone might have some ideas.....

 

If anyone feels like giving me some friendly advise feel free to call me if you dont want to type so much. I hope its ok if i post my cell number here. Tyler 414-248-9668