procomp big block chevy cylinder heads after 10 years on drag car see whats wrong!!
procomp big block chevy cylinder heads after 10 years on drag car see whats wrong!!
this is a look at a pair of pro comp / speedmaster 320 cc rectangle port bbc heads that were ran on a drag car for 10 years. they were used and abused by the owner. see what i found thats wrong with them.
video of car they were on
video was taken by youtube user cadpwr
subscribe link
https://www.youtube.com/channel/UCs8A-8Jq5FQDR39CUJo7pfw?sub_confirmation=1
help to translate link
http://www.youtube.com/timedtext_cs_panel?c=UCs8A-8Jq5FQDR39CUJo7pfw&tab=2
canfield brodix afr procomp jegs summit patriot speedmaster flo-tek renegade revolution edelbrock holley dart world products blueprint rhs trick flow promaxx rect oval cylinder head review camaro
lot of low lift flow be had by chopping down those UGLY MASSIVE MACHINIST RIDGES
Looks more like a pushrod length issue to me..but I’m not the one working on it..
I can only run my 69 big block 375 chevelle on VP fuel. ..
dont believe them..its all chinese junk
Look at it this way .if they were that bad they would not been used ten years . i know flotek , brodix and dart use a dedicated steel mold.
Sure, it might not makes sense to spend the money for new valves, seats, and guides for an as-cast Chinese head. However, if the porting was extensive, it might make sense to do all that stuff. I have seen videos of people going to extreme lengths to save damaged heads that were fully ported.
A counter argument is that if you installed high quality guides, seats, and valves, you would get significantly more than 10 years out of those heads, making the who job worthwhile.
10 years of drag use, I’d say I hardly see anything “wrong”
per se.
I’ve often heard about Pro Comp/Speedmaster heads being perfectly fine as long as they’re inspected by a reputable shop before being installed. The consensus being “Don’t buy them assembled, buy just the bare heads, have the shop double check the machining, then put the RIGHT valves, springs, etc in them.”
I found this video doing research for my big block Ford restoration project. Not gonna be a race engine, so will probably go with something like this. Thanks.
10 years of abuse at the racetrack. They don’t look too bad. Lash caps would fix the cracking problems on the edge of the Valve stem. The early PC heads had problems with seats loosening, so your lucky. Considering they were cheap to start with, putting any time and money into an old set of Chinesium heads like this is a waste of money.
Quality materials and machining cost money, this is where the Chinese cut corners to make a cheaper product. However, they are getting better as more and more American companies abandon making stuff in America in exchange for making a buck or two.
chinese junk..stay away…
Looks reusable. Change out the guides and machine in new seats and it should be good as new.
Heads word good I have a set off 302 227 runners valves and guide were junk , I change everything to ferrea and comp cam components haven’t had a proem since
I’m amazed they lasted that long…
Ive have a set of speedmaster 220cc on an sbc and immediately had guide issues on center exhaust ports, stuck an exhaust valve after 15 minutes run time. Heat stuck the exhaust valves on #4 & #6. Pulled them, replaced the guides and clearanced and haven’t had an issue since. I bought them bare and added my own choice of components. After 2 years they are still doing good in a street car..
I bought these, ran sets with comp springs and manley valves. and they all still run great. I would rather spend 600$ for a bare set of these and add my own parts ! than buy 4,000$ heads that last the same or less.
Was he running a mechanical roller cam? looks like they were out of lash….
Engine reconditioner myself that’s pretty good for 10 years found with pro comp valve geometry is crap and guides are poor quality
I calculating more or less around 1200 total miles with around 250 wide open throttle miles on these heads, hard to say if good buy or not but it seems heads were near catastrophic failure.