Hi,
i h ave this thread on the tech/misc forum, although i tihnk all motor guys know more about this stuff. All motor always has ported heads.
So i bought this head, JG Pro Series Gen 2 head from a buddy of mine through a shop. The car was wrecked therefore it was being parted out. The shop pulled the head off the car, inspected it and told me it was in perfect condition. They said the car ran fine. The head has about 3,000 miles on it, it was boosted on also. They said its not stamped because it was done as a side job. I trust the shop along with the guy who sold it to me.

I have a fully built bottom end that cost me about 3500 dollars that im putting this head onto. So to make a long story short, im afraid this head will fail on me and drop a valve or do something horrific like that. Therefore I'm taking this head to Endyn, a very good local machine shop. They will:

- Flow the head to ensure ports are even, that way it will run right.
-Test Spring Rate
-Check for cracks
-Check valve guides, seats, valves,
-Mill the head
-Re assemble it

What other tests should they preform to ensure a good head, that wont fail and damage anything when ran?

They said if it is uneven flow, they can go and work the ports to get them even, IF the ports are small enough.

So i have attached pics of the head, with pics from EACH intake port, along with pics of the retainers, springs, and valves.

Please let me know if the ports are big enough in which they cannot be worked anymore.















Now most of my buddys are telling me that im paranoid like ****, and should calm down and just take the shops word by just putting the head on the new block and running it.

The shop is well know, i trust them along with many others that trust them. I understand if the ports are different, it wont run right. But i want the main things such as dropping a valve etc...

Head mechanic of the known shop inspected it thoroughly, cleaned it up. It actually belonged to his brother.

Im afraid of that. If my 3500 dollar bottom end ***** up, i wll be fucked in the *** for life. Probably wont be able to finish my build for another year. That would suck

So engine builders, machine shops, tuners, even regular HT members give me input on the tests i should get done and the work of the head.

Thanks Alot

Cliff Notes-
- What tests should i do in order to ensure the head wont fail on my brand new 3500 dollar block
-Are the ports big enough in which they can no longer be worked anymore?
-What do you think of the whole head?

Thanks

 

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i think endyn is a h-t member, pm him with your questions, he will be a lot more informative than most of us are, and he will be able to answer all of your questions

 

The port work looks clean to me.

 

take it to a place that has a flow bench and see if flows good.. also check to see how much was taken of the head when resurfaced.maybe the head was resurfaced like 40 or 50 thousands off..(just a guess)..stuff like that ..thats just my opinion.. i dont know ****

 

Ports look fine, and does not seemed to surfaced that much. If you are worried about dropping a valve, pay the shop you bought it from for new valves, springs, retainers. That is your only shure proof way.

 

yah the ports look alright. they also left the guides so that is reassuring from a longevity standpoint. you can have endyn test the seat pressure of the springs and visually inspect the retainers. you may also find a flow benefit from a different valve. props to you for being patient and making sure everything is in working order. better safe than sorry

 

Yeah alot better to be safe than sorry.

I must admit doing this fully built motor + turbo to aim for 500whp is costing me a little over $10,000. Due to fact i had to replace EVERTHING on the car. It would be sad to ruin the 3500 dollar bottom end over some ******* valve dropping, or spring failing.

So the more input the better.
Thanks Alot guys

 

anyone else w/ more input?

Thanks

 

bump

 

Those look like JG aluminum retainers on those valves. I would replace those as they are weak and break easly. I learned the hard way when after less than 1500 miles I dropped a valve and needed to do a full rebuild.

 

what were the RPMs that the head made? How hiigh were the RPMs to cause the retainer to break?

Thanks

 

I never spun more than 7.5k on the head, it's an F22 so it's not a high revving motor. I was driving down the GSP at like 3000 rpm when the retainer let go. It wasn't pretty. Here's the aftermath.

 

ouch...

Thats a JG Head?

Was it only the piston damaged or the wall etc?

 

To me that doesn't like look like a JG pro series 2 head and on top of that, it doesn't have a stamp..Hmmmm They lied to u dude. I personally have distributed many JG heads and the pro series 2 port+valve work are more extreme than in the pics. Go to <U></U>www.jgenginedynamics.com to look it at yourself and notice what it says on the site which says watch out for Fake Junk JG wannabe heads.

 

the shop i bought it from said it was a side job.

Oh well do the ports look even for each cylinder? Valves, springs and retainers looking good?

Thanks

 

ur gay and super paranoid

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM00SI &raquo;</TD></TR><TR><TD CLASS="quote">ouch...

Thats a JG Head?

Was it only the piston damaged or the wall etc?</TD></TR></TABLE>

Yup JG head with &lt; 1500 miles. JG assembled and all.
Two other retainers also had chips broken off, and within the next few hundred miles I'm sure would have dropped their valves too. Oh and JG couldn't care to make good on this at all. They wouldn't even inspect the head. All they kept saying was "We'll send a call tag, and UPS will be there to pick it up tomorrow." For months, then I decided to go to a reputable builder and had M2 in NJ build my new head.


I wish it was, needed to overbore from 85.5mm to 87mm to take out all the damage and get shelf stock pistons that would work.

 

ouch.