topspeed1

iTrader: (2)

I put the car back on the dyno and immediately noticed a rattle sound coming from the top of the motor. I brought the car back in the shop and compression tested it, driver side rear cylinder was at around 160psi. I pulled the head of and the piston was chewed up. After removing the valves from the heads i notices a large chunk of the valve guide is broken off. What the hell?

They are brand new trick flow 255's only and few dyno pulls on them. What now? What could have caused this? Defective? Cracked when the heads were put together?

Input please.

topspeed1

iTrader: (2)

Darth_V8r

iTrader: (4)

That really sucks.

As to how it happened, that looks like a powdered metal guide, and it likely had a non metallic inclusion for it to fail like that. Without seeing it in person or looking under a microscope, that is.

Edit - are you missing some aluminum near the base of the valve guide also?

topspeed1

iTrader: (2)

No the aluminum is just really thin around the guide but none is missing

handyandy496

iTrader: (9)

How is Tricky Flows warrantee?

topspeed1

iTrader: (2)

According to their website it should be covered. I contacted them today but i havnt heard back.

handyandy496

iTrader: (9)

What's the valve look like? Rocker? Your lucky you caught it right away.
The piston looks ok and you might get a free head. Might be a bad batch of guides or a one off with a fracture. I wonder if they x ray the guides before installation?

topspeed1

iTrader: (2)

Valve and rocker are fine. My problem is that it's got me gunshy about the rest of the guides. Im nervous if i put it back together and it happens again it could be far worse.

Darth_V8r

iTrader: (4)

I would want to replace them personally. Defects are usually in batches

spanks13

iTrader: (5)

Excessive guide clearance?

Looks most likely to be a defect in the guide.

topspeed1

iTrader: (2)

What are your thoughts on powdered metal guides in general?

pantera_efi

iTrader: (1)

Hi TS, I fit a steel guide when possible, our Induction Hardened German Steel Guide.

I can supply our Steel Guide ?

MY GUESS is another FOUND CASE of a cost reduction COSTING END USER BIG MONEY (-.50 cents savings each guide)

Lance

MuhThugga

They are used in millions of OE applications. They don't wear like bronze guides do.

Darth_V8r

iTrader: (4)

In general, I like powdered metal. It's is usually quite consistent from part to part, which is one of the big advantages. The only real downside, it won't be as "solid" as a, err.., solid cast piece. There is always some measure of porosity. And when things go wrong, they tend to go wrong in batches, so with one failing, i'd replace them all. But I would not expect the replacements to also have defects. Where powder is ill-suited is in applications where it's going to be very thin, threaded, knurled, etc. It's still not as tough as cast and machined steel.

Yeah, the difference is that bronze wears BEFORE the valve stems, but that itself can cause other issues. Especially with a very hard valve like titanium - hence the LS7 valve breaks you hear about from time to time. For stainless, which is actually quite soft, bronze guides are great. But GM did their homework on everything, and it's not like there are broken down GM's from bad powdered guides on the end of every driveway right? So, powdered is not bad. OP just got unlucky and got a defective one.

I have to say, I'm very tempted to run these with the titanium valves in mine. When I upgrade the heads, Ill be in touch.

1FastBrick

iTrader: (16)

What is your cam size?

What rockers are you running?

How high have you spun the motor?

topspeed1

iTrader: (2)

It is a comp 297lrr .624 lift 247i 265e duration at .050

Stock rockers with trunion upgrade

7800 rpms is the most i have turned so far.

MuhThugga

Agreed. Every part has a defect from time to time. It is unfortunate for the person it happens to, but it certainly doesn't mean that the entire design is terrible.

Bronze also has certain inherent lubricating qualities. The downside is that it is soft, so any sort of sideloading is going to exacerbate guide wear. This is why a roller tip rocker is heavily suggested for any head with bronze guides.

topspeed1

iTrader: (2)

I still dont have an answer from Trick Flow. I have sent them several emails today and a voicemail. with no response. I understand that racing is racing and stuff happens, but i feel like this i a cut a dry manufacturer defect.
Here is a copy of their warranty

Trick Flow Specialties guarantees original, unmodified cylinder head castings against manufacturing defects. Trick Flow Specialties’ liability is limited to replacing the casting.

The valves, valve guides, valve seats, valve job, valve springs, valve spring retainers, valve locks, rocker arm studs, guide plates, and valve stem seals included on assembled Trick Flow Specialties cylinder heads are warranted to the original purchaser to be free from defects in materials and workmanship for a period of two years from the date of purchase.

This warranty does not cover:
• Failure due to improper installation or maintenance, abuse, misuse, unauthorized repairs, modifications, or alterations determined at the sole discretion of Trick Flow Specialties. If your machine shop, engine builder, or installer performs any unauthorized repairs, the warranty is voided and Trick Flow Specialties will not reimburse any cost you incurred.
• Removal or replacement costs.
• Costs incurred due to down time of the vehicle.
• Damage to related components.
• Marine salt water corrosion.
• Corrosion from not using and/or refreshing antifreeze.
• Fitness for purpose or merchantability.

All other Trick Flow Specialties products are warranted to be free from defects in materials and workmanship for a period of 90 days. There are no mileage limitations.

I bought them on January 15, 2018 which was 60 days ago

Jimbo1367

I'd pester them until I got the words "under warranty" from them.

topspeed1

iTrader: (2)

Well i guess trick flow obviously isnt gonna help me out, so im gonna have to pay out of pocket to have them repaired. Also Im gonna install bronze valve guides and say the hell with the powdered metal ones. Going to get a new valve job too.