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emergency engine surgery!

1

1DOWN6TOGO

Guest
HELP!
had major power loss this weekend. checked all of my cylinder pressures. significant pressure loss on 6 of the cylinders made me guess it may have been a blown head gasket.
took off the heads. i was right. blew the driver's side head gasket.
the gasket membrane between the middle two cylinders was shot. and i had a large piece of piston chipped off of one. looks like she had a heart attack. so now my baby is going into open heart surgery, this weekend.
i'm pulling out the engine and replacing the one piston and heads and head gaskets.
i could really use some advice on heads. the ones i had on were 882, i believe that was stock. i think i definitely shouldn't be running on stock heads with all of the compression my stroker puts out and i'm assuming it would run more efficient with my xe268h comp cam if i had a different set of heads.
i really need recommendations for heads. there is a swap meet in town this weekend and i'd like to check around for a good set, but i don't know what to look for.
HELP ME! PLEASE!!!

thanks
sam
 
1

1DOWN6TOGO

Guest
worst gets worse

my sis let me borrow her 95, 5.slow mustang until i fixed my engine. well i haven't even started fixing it yet and i got in a wreck with it. how's that for luck.:hb
well i've got a ton of pressure to get her fixed ASAP.
any help would be appreciated.
thanks
 
1

1DOWN6TOGO

Guest
just replying to get attention
kinda hopin' to catch C3 guys you haven't seen this yet
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
I'm really confused

"Significant pressure loss on 6 of the cylinders"
Ok I get this.. what were the readings?

"blew the driver's side head gasket.
the gasket membrane between the middle two cylinders was shot."

How did this affect the other cylinders? you just should have had 2 holes down in compression...?

"I had a large piece of piston chipped off of one."

From what..valve hitting..piston hitting head.. how big of a chunk..is the cylinder wall scored?

So what budget do you have to work with??

( assuming none from your following post )

What is wrong with the heads now?

the 882's were a good med preformance head..what valves did you have in them..?

Still need more info....

But DO NOT get swapmeet heads...

I just sunk a WHOLE bunch of $$$ into my Double humps.. when I could of bought NEW EDLEBROCKS FOR LESS $$$$$$


But I wanted STOCK Chevy...silly me!


Vig!
 
S

sscam69

Guest
If you have the money the AFR 195 heads will complement that cam that you have really well!

Otherwise look into sportsman II iron heads, the are the next best thing in bang for buck.

Good luck
 
1

1DOWN6TOGO

Guest
Vig

well my dad took the readings becuase i had never done it before and didn't know what pressures to look for.
the results were like this. on the passenger side- 3 cylinders had over 120 psi. one read 60. on the driver side- 3 cylinders read 50 psi. cylinder 1 read 120. makes sense, because the 3 cylinders on the driver side had breaks in the gasket. large breaks almost and inch and a quarter wide.
the broken piston looked like this- it was missing a piece about an inch and three eights wide and three eights off the diameter of the piston. located directly in line with the missing gasket section. not horribly deep, but made the rings visible. haven't found any piece yet, so i think as of right now, that the piece made it's way out the sidepipes. the local chevy hot rod mechanic speculated that the piston was broken by the added pressure from it's neighboring piston. Luckily there was no scoring, no scratches. very clean, smooth cylinder walls

here's the deal with the heads. (stock valves) when i was putting together the engine initially. i had the heads machined by a local shop which has a good reputation. at the shop they found that the driver-side head was cracked. they had a set of heads on hand and i bought one and had them machine it as well to replace the cracked one. hmmm.... looks like i screwed up there :duh

so the way i see it, if the heads were machined poorly, they need replacement. if i can reduce pressure or gain performance in any way, then they are worth replacing. otherwise i'd have to get them remachined.
so replacing them just sounds the best option. my problem is $$$ and time. mostly time. i am a college student working full-time for an engineering department. i have almost NO freetime. i think i can afford about $300-$400 for the entire job. the machine shop which i bought the gaskets from, is going to replace them for free. they were a good set of gaskets. i know that i will easily spend over $50 replacing all of her fluids. so i'm looking at spending under $300 if possible on heads. then again, i don't know how much $ i'm looking at with new heads. we'll see.

thanks for helping

and Thanks SSCAM69
for the recommendations
 
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1DOWN6TOGO

Guest
i'm searching through summit's online catalog and i can't find AFR 195.... what brand is AFR?
 

AKRAY4PLAY

Well-known member
Joined
Oct 14, 2001
Messages
584
Location
Wasilla, Alaska, U.S.A.
Corvette
'77 L-82, black on black. Full mod 406 small block
AFR stands for air flow research. they are awsome heads, i have a set on my motor. problem is they know how good the heads are and charge accordingly. a set of 195 afr's is in the range of $1100 to $1300. as for your time and wallet crunch, go to the local chevy dealer and get some vortec iron heads. they flow very well for out of the box kit style heads. they are about $400 to $500 a set. you can view them on the jim pace performance website. as for your piston cracking, a blown head gasket will dump water into the cylinder. water does not compress very well. check your rods when you go to replace that piston. it is a good idea to pull a good piston and weight it against its replacement, you do not want to throw the motor out of balance!! your stock 882 are pretty much junk when it comes to building a motor. they are imfamous for providing the kind of experiences you are unfortunately experiencing. best of luck, brian
 
S

sscam69

Guest
your not going to find AFR in the summit catalog, they are an independent company and keep to themselves. The sell some of the best bolt on aluminum heads and outflow all the others. Considering that they are aluminum and flow good the price for the heads are right on IMO. The run about $1250, sorry didn't know what kind of budget you had to work with.

my problem is $$$ and time. mostly time. i am a college student working full-time for an engineering department. i have almost NO freetime. i think i can afford about $300-$400 for the entire job

Gee why does that sound familiar. I just graduated with a BS in mechanical engineering and I am currently working on my masters. Now I have free time but I don't have a garage to work in and we are hitting 100 degrees on a regular basis. Now I have time but don't have $$$$. Isn't that funny. I will be a Teachers Assistant (TA) this semester in my eng. department. I am going to book it for a job, thats what I really need to do now. Ramble off!!

The reason I suggested the sportsman II is because they were the next best thing to the AFR heads in terms of bang for buck and they can be had for about $700-$800 ready to bolt on. Yeah i was looking for some budget heads to:cool But if your budget is that low, or you can't get a loan from your pops (remember I stress LOAN) to help you out for those sportsman II's then your best bet is just to reuse the stock heads if they were not damaged. Oh those sportsman II's should compliment that cam to

Frank

AFR is the acronym for Air Flow Research. I am definitely going to put those on for a future build.
 
S

sscam69

Guest
Carefull with those VORTECH's they have hidden costs and they are going to cost you in the end at least $600 or more. The sportsman II's have a lot more potential for the future and your going to pay the same thing in the end.

Yeah I did some research on those to! If you want the details on those vortechs just let me know, I can save you some time because I know you need all of it!! LOL
 

Jack

Well-known member
Joined
Dec 27, 2000
Messages
1,825
Location
Florence, SC (Timmonsville SC)
Corvette
71 War Bonnet Yellow VERT 71 BH Blue CPE (SOLD)
Sam:
What type of pistons--- cast, forged, hypo--- flat, dished, popup? What is deck clearance ... how far down in hole is piston at TDC?

All heads can/will crack ... for no solid reason ... or a variety of reasons ... the 882 is certainly no exception ... they can be a bit thin! Unless it's already clear the heads are trashed, have a competent auto machine shop pressure test & magnaflux both heads. Here's where I'm going--- we recently blew an sbc motor in a circle track super truck ... a thirty over zero-deck flat top 350 with shaved 882 heads. I actually heard it in pit when it broke at WOT on track. Came in hoternhell ... radiator cool to touch ... ARGH ... no water. Back at shop we pulled it down & found blown head gasket. But here's what caused the failure(s)---VERY small cracks in head's chamber radiating from valve seat. This let water in cylinder ... TOO much water. Cylinder then hydrauliced (or hydo-locked) ... as AKRAY said water doesn't compress much at all. This extreme cylinder pressure blew the gasket ... AND ... cracked the liner both longitudinally & radially. We could tell from closely inspecting liner cracks, rings piston that liner cracks were result of water & not cause of it. Liner cracked longitudinally from 1/4" below deck about 3/4" futher down ... AND cracked radially at that same spot about 3/8" wide ... kinda forming a very faint TEE. Because of the location of that radial liner crack, machine shop recommended NOT to sleeve ... block is junk. BTW, we run this same block-head-piston combo in a flock of race cars-trucks ... run all nite at 6400 rpm ... w/ rare cracking problems ... but it does happen.

Lemme suggest what may've happened to your's --- heads may've cracked letting water in, cylinder hydro-locked, blowing gaskets & and cracking piston. I dunno ... but it's possible some of this water may've migrated UP intake runners and into plenum ... then down into other bank & blowing gasket.

If you find cracks in head / had enough cylinder pressure to break a piston, you should also have liners checked for cracks & check for bent rod(s). I'd take a look in the pan for a piece of piston. Just my .02. G'luck.
JACK:gap
 
1

1DOWN6TOGO

Guest
thanks everyone for the suggestions.

jack, as far as i can tell, the gaskets around the water journals were still sealed. the breaks in the gasket were directly between pistons and allowed for pressure sharing from one cylinder to another. i will check rods as soon as i drop the pan tomorrow, as well as check the pan for a chunk of piston. btw, i am using flat hypo pistons and i am not certain the clearance.

here's what i have come up with as a solution. i can replace the piston easily enough and check weight for balance.
when i order the piston from Summit, i can order a set of Sportsman II heads. they have an assembled set of 200cc intake runner, 72cc combustion chamber, 2.02/1.60 valve, straight plug cast heads for $399.50.
so this weekend i'll open her up and check for any other problems, and hopefully the next weekend i can put her back together with the new piston and heads. sux to have no car for a week.

y'all think that's a good plan?
thanks for the help!
 
S

sscam69

Guest
for $399.50.
I don't know where you got that figure. I am looking at my summit catalog and I see

$553.00 /pair (pt# WRL-012250) unassembled
$799.00 /pair (pt# WRL-012250-1) assembled

Good luck

Frank
 
1

1DOWN6TOGO

Guest
maybe i found a single head price and did not notice that detail.
799 is 2x 399.50
i'll look and see. thanks for pointing that out.
 
1

1DOWN6TOGO

Guest
so far my car is in the hospital an undertermined amount of time.
life sucks for me.
i can't find any decent heads for less than those $400 a piece. i took a walk through that swap meet to look around. i took Vig's advice and steered my pocket clear of any purchases. i couldn't find anything but a pair of '70 441 heads that were well machined recently going for $400 for the pair. that sux. i talked to a guy who says the problem with my '77 882 heads is that they have some fuel heating system. remember i don't know enough about heads. well he explained that heating the fuel was good for smog regulations back in the day. but now with a modified engine putting out lots of compression, and timing off badly enough. the heated fuel pinged like crazy. sounded horrible, like rattling almost, everytime i stepped on the gas. i'm putting 2 and 2 together and figuring out that the combo of horrible pinging and compression and heat and a crappy head were the likely culprits of my head gasket and piston problem.
the solution is killing me though. i can't find heads. a friend of mine said he can get new vortec heads pretty cheap. and figured a new intake manifold wouldn't be too expensive, so the combo of heads and intake would be relatively inexpensive and the results would be excellent. but i've heard that vortec heads only come with 64cc combustion chamber. that would take away 12 cc and raise my compression. is that too much combustion? would that cause more harm than good? do vortec heads come with a larger combustion chamber? help me!!!
i seriously can not afford $800 for heads. i would pull from my savings for a month. i just got my hours cut at work due to school. i just wrecked my sister's car she loaned me. we don't have rental insurance. i have no car to drive until i fix this problem.
i'm desperate for advice.
pleeeeeease.....
 
S

sscam69

Guest
So I take it your heads are not rebuildable right? or you just want to get rid of them to avoid future mishaps. Are you going to rebuild the bottom end? Your mom/pops can't loan you some cash and pay it off in installments?

I told you about them Vortecs, they are going to cost you the same or more. Watch out for those hidden costs.

Damn I wish I could help, If I had an extra pair of heads I would sell them to you cheap. I know how it feels.
 
1

1DOWN6TOGO

Guest
i definitely appreciate the consideration.
i would kill for free heads right now. but i'm stuck searching.
my parents can't afford to help me right now. the best they can do is help pay some of my bills at the end of the month. unfortuantely i'm falling behind on paying my bills from last month.
so i hafta pay those off first. now i'm stuck carless and life sucks without a car. i'm just drifting along now, until i can get heads.
:cry
do you think the added compression from a smaller combustion chamber will be a negative effect on my already hot and highly compressed engine?
 
S

sscam69

Guest
I don't know for sure

Assuming that you have a zero deck clearance, also depends on the compression thickness of the gasket, you can calculate what the theoretical compression would be. A possible quick fix for your engine with those heads is using an extra thick gasket to drop the compression. Its going to have to be 9.5 or less to not have to worry about knock and your going to have to use high octane with that to. Thats with the assumption you are going tu use iron heads.

Maybe you can get away using lower octane but thats going to be determined from the cam you are using, mostly as a result of the overlap.

Start calling up machine shops and ask. Tell them your situation and how much you have to work with. I am sure they'll have something you can use temporarily, though thier not going to be great heads.

All these suggestions are just to get you on the road, not for performance. I don't think you have that luxury right now. Hope this helps. I look for something tonight, maybe I'll turn up something for you.

Frank
 

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