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Sorry for the confusion...current heads are re-worked truck heads...Engine is a 78 Vette L-82 which originally came with screw-in studs and guide plates. Current heads are reworked truck heads...no guide plates. new heads are Summit cast iron heads... Summit Racing SUM-152123 Summit Racing® Cast Iron Cylinder Heads for Small Chevy | Summit Racing
Have you already purchased these new heads from Summit? Small heads, lower compression probably won't give you the performance the old worked truck heads will at 72cc chambers and 165cc intake runners... You may actually lose performance on this motor. And depending on the head gasket you choose, you may lower your compression even more. Not sure without knowing more about the truck heads you had on here before... You have the head #s on those by chance? There are plenty of good cheap budget heads out there if #$ is tight and unless you already purchased these, you could probably find a better head for close to the same price...
 

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In the middle of changing out my heads, I discovered that 9 of my pushrods are damaged... Below are pictures of a few of the pushrods and one of the rocker arms. (The one at right rear is normal-undamaged)

View attachment 426226

View attachment 426227

Has anyone ever seen this or have an idea why this would happen?
Normally, I'm more of a lurker, but the rocker arm cup looks like it has had electrical arcing occurring. The poor pushrod looks like a hammer was on it. I once had a steel braided power steering hose fry do to a poor ground cable, Just saying, I think your on the right track.
 

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Discussion Starter · #23 ·
Have you already purchased these new heads from Summit? Small heads, lower compression probably won't give you the performance the old worked truck heads will at 72cc chambers and 165cc intake runners... You may actually lose performance on this motor. And depending on the head gasket you choose, you may lower your compression even more. Not sure without knowing more about the truck heads you had on here before... You have the head #s on those by chance? There are plenty of good cheap budget heads out there if #$ is tight and unless you already purchased these, you could probably find a better head for close to the same price...
Old heads were #454's opened up from 1.50/1.72 to 1.60/2.02 & pocket ported w/161cc intake runners and 76cc chambers... New heads (already purchased) are Summit (made by Dart) with 1.60/2.02 w/165cc runners and 72cc chambers. I also plan to run a thinner head gasket... So, compression should be a little more than I've had.
 

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Old heads were #454's opened up from 1.50/1.72 to 1.60/2.02 & pocket ported w/161cc intake runners and 76cc chambers... New heads (already purchased) are Summit (made by Dart) with 1.60/2.02 w/165cc runners and 72cc chambers. I also plan to run a thinner head gasket... So, compression should be a little more than I've had.
Yeah, definitely a better head for sure!! The old 454 were pretty smoggy.
 

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Discussion Starter · #25 ·
Normally, I'm more of a lurker, but the rocker arm cup looks like it has had electrical arcing occurring. The poor pushrod looks like a hammer was on it. I once had a steel braided power steering hose fry do to a poor ground cable, Just saying, I think your on the right track.
I never heard of that happening!
 

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Add guideplates then you’ll just break rockers, typical bbc failure when lift, spring pressure, etc not compatible with large lift/ duration cam…IMHO
good luck
 

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Discussion Starter · #29 ·
QUESTION: Getting ready to re-assemble rod's & rockers. Also then need to adjust the valves. The car has been sitting for 2-3 weeks. Should I squirt oil on the lifter cups lifter cups? To possibly help them be more pumped up for when I adjust?
 

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QUESTION: Getting ready to re-assemble rod's & rockers. Also then need to adjust the valves. The car has been sitting for 2-3 weeks. Should I squirt oil on the lifter cups lifter cups? To possibly help them be more pumped up for when I adjust?
You don't want them pumped up when you adjust them at all. The pre-load is set without any pump so if you pump them, it has a tendency to partially open the valve or provide more pre-load than necessary. It's actually best to adjust them without any oil in them at all except assy lube at the cup, face and in the lifter bore.
 

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Put assembly lube on top and bottom of pushrods and the valve tips. Don’t worry about the lifters they should already be purged of air.
 

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Discussion Starter · #33 ·
Put assembly lube on top and bottom of pushrods and the valve tips. Don’t worry about the lifters they should already be purged of air.
ok thanks--Just ran into a problem...Head doesn't seem to want to set down flat on dowels... Goes in back side and starts on front but not down snug. Suggestions?
 

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ok thanks--Just ran into a problem...Head doesn't seem to want to set down flat on dowels... Goes in back side and starts on front but not down snug. Suggestions?
well, first things first, check the dowel alignment holes in the heads for obstructions, then see if the dowels themselves have any rust or debris on them... How is the gasket seated on the dowels? Any raised areas?
 

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Or is the head cocked front to back? If you try and slide the head onto the dowels and the head is not perfectly parallel to the block, it can bind up... Just something to watch for. Especially if you're installing aluminum heads since they're so malleable.. they tend to stick more...
 

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Discussion Starter · #36 ·
Gasket seems to be seated well. Holes in heads are clean... dowels seemed very clean...will check again
 

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Discussion Starter · #37 ·
Or is the head cocked front to back? If you try and slide the head onto the dowels and the head is not perfectly parallel to the block, it can bind up... Just something to watch for. Especially if you're installing aluminum heads since they're so malleable.. they tend to stick more...
That may be it... Will try again...
 

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Okay--- I cleaned dowels better and got it pretty much on but needed to tap w/ rubber mallet to snug it down...
Awesome! that'll happen. Gotta make sure they're really super clean so there's nothing impeding the seat of the head to deck and gasket. The smallest of specs of garbage in there can wreak havoc on leaks and the gasket, maybe not right now but in a couple years when it fails from the leak and rust/corrosion. Good to hear it was an easy fix!! Lube those dowels up!!
 
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