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Big Problem, Need Advice

  • Thread starter Thread starter ProCharger GT
  • Start date Start date May 23, 2005

ProCharger GT

Member
Jun 3, 2004
153
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Cleveland
May 23, 2005
#1
  • May 23, 2005
  • #1
Ok well...about 2 weeks ago I was driving home, going about 20-25 MPH down the street. So I'm cruising, not beating on it or anything, and all of a sudden I hear this odd pinging noise. Well I'm about 15 minutes away from home, it's about 11:30 PM and it's driving ok, so I drove it home and park it in the driveway. Next day I check to make sure everything looks ok under the hood; no visible problems; everything looks ok. So my friend comes over, takes it for a little test drive and he's going about 25-30 MPH, hits the gas a little bit and the car pops; he immediately turns it off. Car will not start.

Fast forward to this weekend at the mechanic shop; I walk in as they pull the head off and to my horror, the valve spring broke, sending the valve into the piston, pushing it back up into the head and bending the valve into the head. Totally ruined the one piston; I dont know about the connecting rod as I nearly threw up after seeing this.. and to make matters worse, the inside cylinder wall is slightly scratched from the valve bouncing around in there. :damnit: So, total damage is: 1 new cylinder head, all new valve springs, one new piston, head gasket (Cometic gaskets are expensive ****) and either a new block or have the block machined to take out the scratches.

Other problem is I don't have the money for all this right now; especially money to get a new block if necessary. What are the odds of being able to bore this block .030 over and get bigger pistons? Or would it be more cost effective to get a new block , and transfer the whole rotating assembly over? Also, what should I do about the crower valve springs that I used? I'm kinda skeptical about using them again, but they are the only ones that I know of that can handle the lift I am running (.612/.612). Being that I wasn't even romping on the engine, and these springs are made for race application, I don't feel they should have broke at 20 MPH. Think there is anything they can do for me, or am I pretty much SOL?

Here are the specs on the engine:
SHM block, SHM bearings, Manley rods/pistons, Forged Cobra Crank, bored .020 over

Heads:
Patriot Performance stage 2, Crower stage 3 blower cams (.612/.612), Crower high pressure springs + titanium retainers, Patriot valves (forget specs)
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
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223
Sea of Tranquility
May 23, 2005
#2
  • May 23, 2005
  • #2
Damn...I'd be leary too if that would have happened to me. First thing I'd do is call Crower and see what they say. They may want to know if there is a problem with their product. I'd just be a little ticked when I talked to them but not enough to be confrontational. Let them know that you will be going with the competition if they can't stand behind there product. I know that they may be the only one for you application but they don't know that.

Whatever happens it's going to cost whether you go with another block (used if you can find a good one) or bore out yours. Either way I think it will cost about the same unless you can recoup some of your money from the old pistons.
 
0

01SN8K

New Member
Jun 9, 2004
135
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May 23, 2005
#3
  • May 23, 2005
  • #3
.612 lift? have never seen a 4.6 with that high of lift before. haerd it required too much work to accomplish. but your only cure is to either bore the block you have if the scratches arent too deep, or find another one. .30 over may not fix the scratch seeing that your block is .20 over already.
 

ProCharger GT

Member
Jun 3, 2004
153
0
16
Cleveland
May 23, 2005
#4
  • May 23, 2005
  • #4
01SN8K said:
.612 lift? have never seen a 4.6 with that high of lift before. haerd it required too much work to accomplish. but your only cure is to either bore the block you have if the scratches arent too deep, or find another one. .30 over may not fix the scratch seeing that your block is .20 over already.
Click to expand...
It really wasn't too much work; due to the pistons being dished there wasn't a clearance issue at all; except for the first time when they gave me a cam that wasn't ground properly. Well I just got a call from the mechanics so I'll have to check my VM in a bit..hear the rest of the wonderful news.
 
T

Torinalth

Founding Member
Jul 16, 2002
952
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16
Clayton NC
May 23, 2005
#5
  • May 23, 2005
  • #5
was just browsing SHMs used area, lots of REALLY cheap stuff on there in great condition... might want to look there.

Torinalth
 

ProCharger GT

Member
Jun 3, 2004
153
0
16
Cleveland
May 23, 2005
#6
  • May 23, 2005
  • #6
Torinalth said:
was just browsing SHMs used area, lots of REALLY cheap stuff on there in great condition... might want to look there.

Torinalth
Click to expand...

Thanks, I will definitely check that out.

Anybody else know of a spring that can handle the lift I have though? I'm really really skeptical about going back with Crower; I have to call them later on today
 

ProCharger GT

Member
Jun 3, 2004
153
0
16
Cleveland
May 25, 2005
#7
  • May 25, 2005
  • #7
Ok, final damage report:

1 piston, 1 head, 1 valve, all new springs and head gaskets

Anyone have spring reccomendations? I've yet to call Crower as I've been sick; but I don't want to go with them again.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
May 25, 2005
#8
  • May 25, 2005
  • #8
ProCharger GT said:
Fast forward to this weekend at the mechanic shop; I walk in as they pull the head off and to my horror, the valve spring broke, sending the valve into the piston, pushing it back up into the head and bending the valve into the head. Totally ruined the one piston; I dont know about the connecting rod as I nearly threw up after seeing this.. and to make matters worse, the inside cylinder wall is slightly scratched from the valve bouncing around in there. So, total damage is: 1 new cylinder head, all new valve springs, one new piston, head gasket (Cometic gaskets are expensive ****) and either a new block or have the block machined to take out the scratches.
Click to expand...

that valve made contact before the head was off. this was probally what happend when it would not restart after your friend drove it.

if it broke when taking the head off there would have been no damage since the valve sring has no way near enough seat pressure to cause damage. the valve would just bounce off a piston. it would be the same as throwing the valve at the piston.

i would look further into this problem too see what the root cause of the PTV contact is.
 

ProCharger GT

Member
Jun 3, 2004
153
0
16
Cleveland
May 25, 2005
#9
  • May 25, 2005
  • #9
MikeZ28 said:
that valve made contact before the head was off. this was probally what happend when it would not restart after your friend drove it.

if it broke when taking the head off there would have been no damage since the valve sring has no way near enough seat pressure to cause damage. the valve would just bounce off a piston. it would be the same as throwing the valve at the piston.

i would look further into this problem too see what the root cause of the PTV contact is.
Click to expand...
The valve spring broke, thats what had caused the PTV contact. I really dont want to go with Crower again; and I was looking at Comp springs; but is there anyone else that can do a .612 lift?

I've had the cams in the car for about 8 months; had no problem with PTV contact prior to this; so I know the cams will fit the engine.
 

hognutz

New Member
Nov 12, 2002
1,940
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0
albany, oregon
May 25, 2005
#10
  • May 25, 2005
  • #10
I would call some companies. Not sure if I would want to take the word of someone on a message board.

I would call comp, MPH, VT engines, fox lake. any of these companies should point you in the right direction.

I would call Crower first though. It is there part that failed. Causing all this. If they sold you the cam and springs to match I would be in there grill. this is there products fault.
 

ProCharger GT

Member
Jun 3, 2004
153
0
16
Cleveland
May 25, 2005
#11
  • May 25, 2005
  • #11
I will be calling Crower when I get out of work tonight..I'll post as soon as I get new info. Thanks for the help everyone.
 
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