Ford gt engine troubles

Motor had bad hiccup at top of third this past weekend. Shut it down right away and coasted to parking lot. Runs very rough. Oil pressure good, no fluid leaks. When u crank it u can tell it's obviously down on compression in at least 1 hole. Towed it to house and found passenger bank of motor is down on compression. Haven't pulled the valve cover yet.... let's hear some guesses!

FYI built motor with 2800 street miles on it making appx 1000hp tire on ms109.

The whole passenger bank? All 4?

Correct. Well you guys took too long. Pulled the v c and found secondary chain broken. Now onto the why....

The pistons might have kissed the valves in that circumstance. If that happened you probably have some valves that bent and possibly holes in pistons.

DieselDr said:

Correct. Well you guys took too long. Pulled the v c and found secondary chain broken. Now onto the why....

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Took too long?! It was only an hour, lol.

That was going to be my guess! Broken chain or sprocket.

Yes if it is down on all 4 cylinders on one bank you've broken a timing chain or sprocket. You'll either have 8 bent exhaust valves or if it is the primary, all the valves will be bent. Don't ask me how I know this

I was only kidding about taking too long. The secondary chain broke therefore most intake valves should be bent.

I know, I get jokes

Yup, bent valves sounds about right. Sorry dude.

Sucks to hear but you can reconcile the pain with looking at the Ford GT you own
We commonly upgrade the stock secondary chain, unfortunately it appears you found out the hard way. I'll gladly trade you a wonderfully running 800 mile Hellcat Charger for that broke POS.
Seriously though, good luck on the rebuild/upgrade. Any pics?
-J

The chain broke? I'd look at the secondary tensioner as a likely source, but don't rule out a broken secondary sprocket. If a bolt backed off, it might have broken the alignment tooth and when the cam came out of alignment, the chain broke when a valve contacted a piston. I'd go back with a billet set and stouter chains when you fix it. Probably a good time to upgrade some of the internals.

all components are cloyes (supposed to be an upgrade over stock, not sure i believe they are superior). secondary tensioner looked fine and is upgraded to tension proper side of chain. cam rotates freely with followers out. at this point appears to be simply broken chain. there are several instances scattered across the internet of broken cloyes secondary chains. motor will come out this weekend and be headed back to mpr for repairs/ tweaks. will update the this thread with new info.

DieselDr said:

all components are cloyes (supposed to be an upgrade over stock, not sure i believe they are superior). secondary tensioner looked fine and is upgraded to tension proper side of chain. cam rotates freely with followers out. at this point appears to be simply broken chain. there are several instances scattered across the internet of broken cloyes secondary chains. motor will come out this weekend and be headed back to mpr for repairs/ tweaks. will update the this thread with new info.

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Both the secondary and primary chains of the Cloyes kit are stock chains. Nobody makes a Heavy Duty primary chain for this engine. The stock primary is of sufficient strength to handle load, but the stock secondary chains are not. Accufab Racing sells a HD secondary chain to replace the stock gauge chain in the Cloyes kit that works with the billet sprockets of this kit.

https://accufabracing.com/timing-chains/4.6l-5.4l-secondary-timing-chain-set

You can also increase the strength of both chains and reduce friction significantly by sending the parts to MicroBlue Racing to have them work their magic

Kurt,
From the OP's profile, this is a 2006 Ford GT Supercar and not a GT500.

Hey Snoopy

I realized that the gentleman was working with a Ford GT engine with the larger valve covers.

There is no upgrade primary chain for the Ford GT. You're stuck using the stock primary chains regardless of which timing chain system you decide to use, as nobody markets a performance chain upgrade for the Ford GT engines.

The Ford GT primary chain is an upgrade for the GT500 primary chain, but this requires the valve covers to be changed to accommodate the larger primary sprockets at the exhaust camshafts.

If you talk to the engineers at Cloyes about the kit they produce, it is for the Ford GT engine. It will require a valve cover change on a GT500 engine. Cloyes will also tell you that the kit they produce uses both the Ford GT stock primary chains and the stock secondary gauge size chains when comparing gauge size. In fact the engineer I spoke with at Cloyes stated that Cloyes buys the primary chains for this kit from the same manufacturer that Ford purchases them from. They do have available as an upgrade a Z-Racing chain that can be bought separately from the kit to upgrade the secondary chains. From my understanding this was going to be something in the future that would become a standard part of the kit. Unfortunately the secondary Z-Racing chain was NOT increased in gauge size, so the increase in structural strength of these over the stock secondary chains would steer me towards the secondary chains sold by Accufab for a substantial increase in strength when you see the difference in the gauge size The larger gauge secondary chains are required with aftermarket camshafts with higher valve lift, along with the corresponding increase in valve spring seat pressure. Otherwise the stock gauge secondary chain becomes a weak link in the system at high RPM

I noticed that he is working with M2K, I was surprised at the fact the engine wasn't an Accufab build to start with. M2K just set a new Texas Mile record with a Accufab engine at 293.6mph in a Ford GT with twin turbos and a MoTec fuel system. It won't be long and 300mph will be surpassed. I think John has an idea from Shawn Fischer about building a unique Lenco that might help, especially since John bought out Lenco on Jan 1.

Kurt,
I knew the sprockets on the cam drive where different, I just didn't know that it was a larger primary drive sprocket, I was thinking it may have been the secondary drive sprockets.
Thanks for the info.

It is a ford gt.... i posted the thread here because the gt section has basically no traffic.

good to know bad company. I noticed how similar in size the cloyes secondary chain was to the original but i did not realize it was identical. I have been eyeballing the accufab chains. that is most likely what I wlll go with. Also it is worth noting that on my car the cloyes adjustable primary sprockets through a cam sensor performance fault. M2k replaced the adjustment bolts with stainless (non magnetic) but it didn't not fix the issue. I had to shim the cam sensor out away from the sprocket to correct the problem. car ran fine before and after this issue, was just a matter of check engine light everytime you i started the car. I will be going with stock sprockets this time degreed the old fashion way.

As far as an accufab built motor all i will say on an open forum is that John and I didn't see eye to eye. No denying he builds world record motors tho.

M2k picked up the car today. Motor will be out soon. Couldn't possibly say enough good things about them.

Snoopy49 said:

Kurt,
I knew the sprockets on the cam drive where different, I just didn't know that it was a larger primary drive sprocket, I was thinking it may have been the secondary drive sprockets.
Thanks for the info.

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Snoopy, you're welcome. It will be easy to remember that all of the 4.6L 4V, 5.4L 4V and 5.8L 4V engines use the exact same secondary timing chain components. The primary side is where all the differences are.

The only reason Ford changed the primary chain and sprockets for the GT500 was because of the valve covers. With the bigger primary sprockets of the earlier Ford GT engines and the corresponding taller/wider valve covers, the completely assembled engine is too wide to raise the engine between the frame rails of the S197 Mustang. The SVT crew shrunk the primary timing system to install the smaller valve covers, so the engine could be installed without slowing the production line down. Everybody that converts to the Ford GT timing system must raise the engine above the frame rails without the valve covers, than install the valve covers before raising the engine and K-member into its final location in the chassis.

DieselDr said:

It is a ford gt.... i posted the thread here because the gt section has basically no traffic.

good to know bad company. I noticed how similar in size the cloyes secondary chain was to the original but i did not realize it was identical. I have been eyeballing the accufab chains. that is most likely what I wlll go with. Also it is worth noting that on my car the cloyes adjustable primary sprockets through a cam sensor performance fault. M2k replaced the adjustment bolts with stainless (non magnetic) but it didn't not fix the issue. I had to shim the cam sensor out away from the sprocket to correct the problem. car ran fine before and after this issue, was just a matter of check engine light everytime you i started the car. I will be going with stock sprockets this time degreed the old fashion way.

As far as an accufab built motor all i will say on an open forum is that John and I didn't see eye to eye. No denying he builds world record motors tho.

M2k picked up the car today. Motor will be out soon. Couldn't possibly say enough good things about them.

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You're the first person I've heard of having a problem with the Cloyes kit. But you're also the first person I've heard of using it in a Ford GT. You have a different front cover if I'm not mistaken. Evidently there is a slight difference and this caused an issue with the timing sensor air gap between it and the sprocket from what I'm reading in your post.

John can be a lil rough around the edges at first. Once you get to know him a lil he is actually easy going

Also, Google up Iwis chains, made in Germany. People at yellowbullet forums say they're supposed to be the best. It looks like they can custom make chains/ sprockets as well.

Then send off for cryo treating if they can't in house.

I think I'll really look into this if I ever open the front of my engine again.