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S550 Honey Badger GT350 Build Build Thread Profile - S550 Mustangs

1,101
1,071
In the V6L
Two others were a teeny bit loose (maybe a few ft lbs). But none of concern. I'll probably just pulling this engine every offseason and doing an investigative check. Ugh
Two thoughts on this - first, most race engines get a teardown every season, and that's what you have so that's probably what you need to do. Second, having said the first thing, if you're getting it torn down, ask whoever is doing it to tell you whether it actually needed the tear-down at 45 hours, or could it have gone say, 90 or 100. Are the valves ok, are the pistons and rings ok, etc. If the problem with the voodoo in this service is that the main and con rod bolts get loose, then just drop the oil pan every 20 or 30 hours and re-torque them. If that's all that's shaking loose, you're good to continue until everything else is ready for a refresh.

It occurs to me that the fixed valve timing may be a factor in this too - not that it makes the vibration worse, so much as it makes the vibration more consistent. I'm guessing here based on my limited experience chasing piston slap, but with varying cam timing, engine vibrations may fade in and out or change harmonic content, but with the cam timing locked, it'll be what it is all the time.
 
434
454
Exp. Type
W2W Racing
Exp. Level
20+ Years
Snowy North
Which balancer are you using? How much time on it, especially if it's the original Ford piece?

Kinda wondering where your cap bearing clearances/gaps might be now...
 
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Two thoughts on this - first, most race engines get a teardown every season, and that's what you have so that's probably what you need to do. Second, having said the first thing, if you're getting it torn down, ask whoever is doing it to tell you whether it actually needed the tear-down at 45 hours, or could it have gone say, 90 or 100. Are the valves ok, are the pistons and rings ok, etc. If the problem with the voodoo in this service is that the main and con rod bolts get loose, then just drop the oil pan every 20 or 30 hours and re-torque them. If that's all that's shaking loose, you're good to continue until everything else is ready for a refresh.

It occurs to me that the fixed valve timing may be a factor in this too - not that it makes the vibration worse, so much as it makes the vibration more consistent. I'm guessing here based on my limited experience chasing piston slap, but with varying cam timing, engine vibrations may fade in and out or change harmonic content, but with the cam timing locked, it'll be what it is all the time.

I had a similar thought this morning re: the lockouts. As I think you're alluding to, didn't Ford's tune update change the cam timing to minimize cold piston slap?

So first "real" refresh of the built motor was kind of a dud since I had those head issues from a different builder and we had made a couple pistons melty. However, Tim said the rest of the short block was still good and could have kept going if it hadn't been for the oil/tune issues. In the end, it was all refreshed because of the pistons--otherwise it would have just been a head job.

I'm going to put the engine on a stand this weekend and measure everything to see what my clearances are. From what I can tell, it doesn't need a refresh. The cylinder walls (from underneath) look great, the couple caps I popped look great, etc.

But I need to get it on a stand and measure things out regardless.

Which balancer are you using? How much time on it, especially if it's the original Ford piece?

Kinda wondering where your cap bearing clearances/gaps might be now...

ATI balancer, new this refresh.

I still need to measure the bearing clearances, but build sheet says they should 0.0023-0.0026 on the rods and 0.0014-0.0022 on the mains
 
Two thoughts on this - first, most race engines get a teardown every season, and that's what you have so that's probably what you need to do. Second, having said the first thing, if you're getting it torn down, ask whoever is doing it to tell you whether it actually needed the tear-down at 45 hours, or could it have gone say, 90 or 100. Are the valves ok, are the pistons and rings ok, etc. If the problem with the voodoo in this service is that the main and con rod bolts get loose, then just drop the oil pan every 20 or 30 hours and re-torque them. If that's all that's shaking loose, you're good to continue until everything else is ready for a refresh.

It occurs to me that the fixed valve timing may be a factor in this too - not that it makes the vibration worse, so much as it makes the vibration more consistent. I'm guessing here based on my limited experience chasing piston slap, but with varying cam timing, engine vibrations may fade in and out or change harmonic content, but with the cam timing locked, it'll be what it is all the time.
I would say it's RPM related. It's the secondary vibrations due to the difference in inertia of the pistons reaching TDC and BDC. The increase in inertia is a multiple of the increase in RPM.

Edit to add: I don't think the balancer does much if anything to mitigate the secondary vibrations.
 
Just got a note back from Tim, he's wondering if it was possible there was a small balance issue with the clutch. That makes sense given that it was cap #5
 
434
454
Exp. Type
W2W Racing
Exp. Level
20+ Years
Snowy North
New FW is a lot lighter especially where it matters @ max radius...should move the harmonics a bit farther out (rpm) - good!

At the same time, the new clutch/FW assembly is lighter globally...this emphasizes the importance of achieving a tight balance on bottom end+new clutch/FW assembly.

Spec makes great stuff...your new bits are gonna be brilliant.
 
On the note of spending too much money, the snowballing has officially begun. Going to use this as a sign to step back and do some bigger work at the same time.

As mentioned in my other thread, I'm currently exploring a dry sump system. As part of that, I am going to need to do some fab work. That leads me to roll cage and fuel cell.

Roll cage:
For the cage, I have a couple of weld-in kit options that pops and I can do ourselves:
  1. Watson - https://shop.watsonracing.com/S550-MUSTANG-ROAD-RACE-ROLL-CAGE-2015-CURRENT-p/wr-15-roadracecage.htm
  2. Trackspec - https://trackspecmotorsports.com/s550-mustang-gt-gt350-roll-cage-kit
If understand correctly, the Trackspec cage is what the GT4 cars use? Or they're very similar at the minimum. It looks superior to me with all the extra reinforcement, but open to feedback.

The other option is a custom cage from a fabricator. This would enable me to remove a lot of extra material from the car's structure that we don't need and get the bars further away from the driver, but assumed with much added expense that will takeaway from other upgrades. Also not sure I want such a heavily modified interior structure now since I give rides more than 50% of the time I'm out on track.

Open to thoughts and feedback!

Fuel cell:
To make way for the dry sump, it looks like I'll need to move the fuel tank. So i'm thinking the typical 22gal fuel cell in the trunk. Since I run E85, i'm thinking a surge tank is a good idea. Any recommendations here? @Fabman, do you have a recommendation since I know you're running E85 too?

Future stuff:
Not finalized on timeline, but future updates will include a sequential trans and likely some electronics upgrades (ECU, PDM, Dash, etc.) and a more race-focused ABS unit. No idea on timeline, yet. This will really depend on how badly it snowballs. But goal would be to simplify the system, add in more customizability (such as killing engine if oil pressure dies, etc.), improve durability, and of course, improve performance. While I don't think I'm ready to go down this very expensive path just yet, I want to keep it in mind as I make decisions now so it can help reduce churn going forward if possible.
 
The GT4s were/are built at Multimatic. Doubt they would have used someone else's cage when that's their business.

Didn’t mean to imply that trackspec designed it. Have no clue. just Meant they might be a supplier or copy. Either way, it looks superior to the Watson to me. A lot more gussets and reinforcements.
 
5,308
6,040
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
On the note of spending too much money, the snowballing has officially begun. Going to use this as a sign to step back and do some bigger work at the same time.

As mentioned in my other thread, I'm currently exploring a dry sump system. As part of that, I am going to need to do some fab work. That leads me to roll cage and fuel cell.

Roll cage:
For the cage, I have a couple of weld-in kit options that pops and I can do ourselves:
  1. Watson - https://shop.watsonracing.com/S550-MUSTANG-ROAD-RACE-ROLL-CAGE-2015-CURRENT-p/wr-15-roadracecage.htm
  2. Trackspec - https://trackspecmotorsports.com/s550-mustang-gt-gt350-roll-cage-kit
If understand correctly, the Trackspec cage is what the GT4 cars use? Or they're very similar at the minimum. It looks superior to me with all the extra reinforcement, but open to feedback.

The other option is a custom cage from a fabricator. This would enable me to remove a lot of extra material from the car's structure that we don't need and get the bars further away from the driver, but assumed with much added expense that will takeaway from other upgrades. Also not sure I want such a heavily modified interior structure now since I give rides more than 50% of the time I'm out on track.

Open to thoughts and feedback!

Fuel cell:
To make way for the dry sump, it looks like I'll need to move the fuel tank. So i'm thinking the typical 22gal fuel cell in the trunk. Since I run E85, i'm thinking a surge tank is a good idea. Any recommendations here? @Fabman, do you have a recommendation since I know you're running E85 too?

Future stuff:
Not finalized on timeline, but future updates will include a sequential trans and likely some electronics upgrades (ECU, PDM, Dash, etc.) and a more race-focused ABS unit. No idea on timeline, yet. This will really depend on how badly it snowballs. But goal would be to simplify the system, add in more customizability (such as killing engine if oil pressure dies, etc.), improve durability, and of course, improve performance. While I don't think I'm ready to go down this very expensive path just yet, I want to keep it in mind as I make decisions now so it can help reduce churn going forward if possible.
ATL cell with e85 foam and an internal surge tank and an external pump.
 
ATL cell with e85 foam and an internal surge tank and an external pump.
Do you happen to recall what series you're running? If I'm reading the brochure correctly, it looks like the Sportsman 100 and Fuorcell 600 both support E85?
 
5,308
6,040
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Do you happen to recall what series you're running? If I'm reading the brochure correctly, it looks like the Sportsman 100 and Fuorcell 600 both support E85?
Sportsman if I remember correctly….I’ll see if I can dig up some information.
 
Have you defined what series you might race? Sounds like NASA TTU or SCCA U1 if doing time trials. Maybe Grid life?
Spot on. Will be aligning to the unlimited classes (TTU, STU, SLB Limited/Unlimited). Car might be able to be TT1/ST1 competitive with a detune.

Ultimate goal with the car is not to necessarily to be competitively immediately, but have a very rowdy and reliable car to take all over the place bucket list trips and give wild rides to students while instructing. I'd love to be able to pivot to NASA W2W if I get the hankering at some point. I do expect to be doing TT immediately with it, but fine with it being a bit of an underdog against the big players.
 
5,308
6,040
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Do you happen to recall what series you're running? If I'm reading the brochure correctly, it looks like the Sportsman 100 and Fuorcell 600 both support E85?
SP 122B
I'm pretty sure this is my cell or pretty dang close to it.
I had some options added, an internal surge tank, fuel level dipstick and -10 outlet and -8 return fittings. I will see if I can verify tomorrow when I'm at the shop. I got this extra deep one so it would fit between the mufflers I had at the time so its probably deeper than you want. Just pick a similar one with the dimensions that fit your car. ATL was very helpful to me on the phone and put together just the right cell for my setup.


SP122B.jpgST528.jpg
 
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