GT350 Engine Refresh Time!

[honeybadger]

Editing this post so everyone keeps the pitch forks at bay. JPC/RGR are taking care of everything.

Got the heads back from RGR last night. Some surprises.

Heads were decked and polished. The valves look mighty purrdy.

Nice and clean exhaust ports and mating surface.

New PAC Racing valve springs and Ti retainers are in

Peak at the bronze guides

New FP valves I mentioned earlier in the thread

Now to the surprises. First, combustion chamber wasn't smoothed/machined. It was polished, but still retains the factory CNC ridges.

Inconsistency in the ports between heads (specifically on the bottom).

When I spoke to JPC/RGR they said it's because the CNC program is set to "port" to specific tolerance and these areas exceeded the tolerance (read: shitty OEM tolerances were too off). That's all fine, but I would have expected clean up by hand after. Exhaust ports on the same head are similar.

Lastly (and most concerning), I was also surprised to see that the heads weren't thoroughly de-burred. The little metal ridge below is similar across all 16 head bolt seat areas. This is how they come from the factory...but I would have expected these to be de-burred. Not super into the idea of putting this on a recently re-built short block.

Sigh...not entirely sure on the path forward. My gut tells me I should de-burr those and leave the rest alone until Tim at MPR gets my entire long block for a refresh in the future. Thoughts? If agreed on de-burring, recommendations on tools/methods?

I expected a bit more for ~$4,500. No blueprinting documentation/flow numbers were included either. Ugh.

Thanks, ya'll!

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[Schwerin]

It sounds like the shop 85% assed it. For that much i'd have expected better quality work and I'm not even a super picky person. Did you ask why it wasn't de-burred and the numbers were not provided as you expected both?

 

[honeybadger]

It sounds like the shop 85% assed it. For that much i'd have expected better quality work and I'm not even a super picky person. Did you ask why it wasn't de-burred and the numbers were not provided as you expected both?

I made the mistake of assuming both would be done based on reputation (seems all reputable shops would do it, no?). RGR has a great rep and quite a few folks I have personally talked to have used them and been very happy, so I didn't have much concern. I confirmed with RGR that nothing was missed, they just don't deburr the top side of the heads or provide flow numbers for every single head they work. Guess our expectations were different.

Fortunately, Tim at MPR Racing (who did my short block) is more inline with my expectations and will be getting my work in the future.

 

[Schwerin]

I made the mistake of assuming both would be done based on reputation (seems all reputable shops would do it, no?). RGR has a great rep and quite a few folks have used them and very happy, so I didn't have much concern. I confirmed with RGR that nothing was missed, they just don't deburr the top of the heads or provide flow numbers for every single head they work. Guess our expectations were different.

Fortunately, Tim at MPR Racing (who did my short block) is more inline with my expectations and will be getting my work in the future.

Sounds like they expected you to know ask for it if you wanted it, but I'm surprised they didn't ask about that then and offer it as an up sell.

 

[nastang87xx]

The deburring is concerning. The rest of the stuff I can sorta understand because we're talking within some hundredths to thousandths of an inch. I guess I don't know really. $4500 is quite a bit though I agree.

 

[JAJ]

... I was also surprised to see that the heads weren't thoroughly de-burred. The little metal ridge below is similar across all 16 head bolt seat areas... gut tells me I should de-burr those and leave the rest alone ...

I'd leave well enough alone, because if those ridges haven't shed any metal yet, they won't shed any metal when you put them into service. If you start mucking with them to clean them up, you might just create some debris that can cause a whole new set of problems.

I'd just leave them as is until the next refresh.

 

[honeybadger]

I'd leave well enough alone, because if those ridges haven't shed any metal yet, they won't shed any metal when you put them into service. If you start mucking with them to clean them up, you might just create some debris that can cause a whole new set of problems.

Not entirely sure that they haven't caused a problem, tho. My OPG clearly had something go through it and it had to be fine enough to get through the mesh at the bottom of the oil pickup. Plus, I was able to break some pieces off by hand with my fingernail. Coule be fine, could cause problems.

If I deburr, I would remove the valves/springs and do it properly.

 

[Tank]

Plus, I was able to break some pieces off by hand with my fingernail.

Sad news for us all...

I am no expert but I’d remove the valves and at least hit those areas you can flake off with your fingernail. Maybe the more prominent ridges too.

Thanks for taking us along!!

 

[Offboost]

So sad to see this! I have seen better quality from local production machine shops.

It honestly looks to me like they mainly did the guides and valves seat work and basically went over the ports and chambers with a sanding disc and called it ported and reassembled it using the upgraded parts.

So sorry that people can do business like that and get away with it!

 

[Ltsrock]

Seems like the right thing is for them to get them sent back to them and correct their work.
I realize that's not a real option for you because of the timeline that you have setup, but this should be on them, not you.
I imagine it's not what you want to hear but time invested now could equal time and $$dollars$$ saved this track season

If you disassemble them, then you have relieved them of responsibility that they may have had (I know that there's no real warranty on this type of work, but......). It's been a long time since I've done any head work but if I recall, you'll need to lap the valves back in etc.......

Not a good place to be stuck in IMHO.

Sorry to hear about this

 

[honeybadger]

Sad news for us all...

I am no expert but I’d remove the valves and at least hit those areas you can flake off with your fingernail. Maybe the more prominent ridges too.

Thanks for taking us along!!

Agreed on all accounts. Hopefully the mesh filter in the oil pan catches it for everyone. Just another good reason to change oil after track events

So sad to see this! I have seen better quality from local production machine shops.

It honestly looks to me like they mainly did the guides and valves seat work and basically went over the ports and chambers with a sanding disc and called it ported and reassembled it using the upgraded parts.

So sorry that people can do business like that and get away with it!

I know for a fact they CNC'd the porting. They just don't clean up missed spots by hand after.

Seems like the right thing is for them to get them sent back to them and correct their work.
I realize that's not a real option for you because of the timeline that you have setup, but this should be on them, not you.
I imagine it's not what you want to hear but time invested now could equal time and $$dollars$$ saved this track season

If you disassemble them, then you have relieved them of responsibility that they may have had (I know that there's no real warranty on this type of work, but......). It's been a long time since I've done any head work but if I recall, you'll need to lap the valves back in etc.......

Not a good place to be stuck in IMHO.

Sorry to hear about this

First route I tried with them. This isn't "bad job" according them. It meets their quality control...unfortunately. At this point, I am confident enough in my own abilities. Besides, if something went wrong and I hadn't touched them, they still aren't going to warranty the work. Unfortunately that's the risk you take with aftermarket.

 

[Ltsrock]

First route I tried with them. This isn't "bad job" according them. It meets their quality control...unfortunately. At this point, I am confident enough in my own abilities. Besides, if something went wrong and I hadn't touched them, they still aren't going to warranty the work. Unfortunately that's the risk you take with aftermarket.

Ohh ok. I didn't know that piece of information.
Seems to me like they're not doing themselves any favors. The forums are where lot's of past and future customers go to find out who are the best of the best (reputable shops). IMHO, this is a huge mistake for them. For me, customer service is at the top of my list, second only to quality of work.

I'll stop there, I believe that this isn't intended to start flaming RGR, and is not your style.

Best of luck and I'll certainly be following your build and escapades. My available track time and budget only allows for to live vicariously though others, thanks for your info and build/track stories.

 

[Hack]

I agree on the deburring. I wouldn't want those little flakes floating around in the engine.

I wouldn't worry about the ports. The issue is that the casting is really, really good. So good that a preferred machining program ends up barely touching the ports at all. I understand if you want to polish the exhaust ports, but I wouldn't remove any material from them.

 

[Strokerswild]

Deburr.

At the caliber of this build, not to mention the RPMs involved, EVERYTHING should be deburred.

When I built engines on the side I was pretty anal about deburring, even on pretty basic street stuff (probably why I never seemed to make much doing it, LOL). In addition to little metal flakes that can become oil-borne, burrs can lead to cracks.

 

[stanglife]

When I built my Boss motor, starting from a bare block... I was surprised at how much machining was lift "dirty" and I did get a small file to knock everything off prior to assembly.

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