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Nick, are you able to retain the function of the intake manifold runner actuators with the steel oil lines on the back of the heads? Is there a PN for the lines or are they custom? Thanks.
Duane, Yes. The crossovers just balance oil flow/pressure between cylinder heads...
No P/N. They're copied from the FP350S.
 
Sorry to hear this and hopefully it's not too bad. Whey is it always #8? Also that cart must be stronger than it looks.
 
741
1,075
TX
If you can, please get detailed pics of the retainers, Pistons/rings and bearing wear! I'm in the middle of refreshing my motor that has 42.5 hours and all but the valve seals looked really good. Only doing new seals and timing-related components this round. Curious to see how yours have worn for more data.

My cylinder #8 also seems to have run a bit hot. Doing the cooling mod to see how that goes.
 
741
1,075
TX
I ran that cooling mod for a number of years, I don't believe it does anything really meaningful. #8 plugs and cylinders always looked more hot.

Yeah...most evidence seems to be inconclusive. I'd had engineers tell me its a good idea and other tell me meh. I'd figure I'd give it a try this time and see what happens.
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
4,008
1,924
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Exp. Level
10-20 Years
Cookeville TN
I do think that reading temperatures away for the back of the heads will be inconclusive in this case. Coolant flows first down the heads at the exhaust valve side, then loops back past the spark plugs, intake valves and down the block passages and out to the radiator. The thought is #8 sees the water flow last and therefore it is the most heat saturated of the initial coolant flow. Checking temps at the bypass and at the lower left block core plug would tell a alot about what is happening. I am adding the MMR loop because in the end I don't think it can do harm and may help quell the #8 hot spots/detonation. Some tuners richen #8 a scosche to cool it down with fuel a bit.
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
It certainly won’t harm anything, I just never added it back to future engines. I had wanted to dig further on the analysis side of that and try to get more accurate temperature recordings but just was never able to justify the effort to quantify that. Maybe some of the younger tech crowd can pick up and run with that :)

I had shifted my strategy to lowering the temperatures as a whole system


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@the5 Turns out it is the GT4 piece, made by Sachs.

I sourced mine through Capaldi. They did the prove out for GT350/FP350S although FP never ended up adopting it. Call Leo or Craig.

You’ll need to install a stop for the clutch pedal to avoid over throwing the clutch.
 
Black Boss, I’m wondering if you can provide a bit of clarity on 18” wheel figment.

I recently switched to the AP “endurance” front brake kit on my 350R, and want to go to an 18” rotatable wheel setup. If I’m reading correctly, are you suggesting that the proper secs are the GT4 wheels and not the FP350S wheels?

Thanks!
-Spencer
 
Black Boss, I’m wondering if you can provide a bit of clarity on 18” wheel figment.

I recently switched to the AP “endurance” front brake kit on my 350R, and want to go to an 18” rotatable wheel setup. If I’m reading correctly, are you suggesting that the proper secs are the GT4 wheels and not the FP350S wheels?
Thanks!
-Spencer
Hi Spencer,
I’m running the GT4 spec offsets on my my race wheels. For Wets and non race events I’m running APEX square with 31mm spacers up front. I believe the FP350S offsets will work.

You may already know, but one other note. 18” wheels will not fit the rear OE brakes. You’ll need to go with AP rears also.
 
741
1,075
TX
Update on the engine: One of the Intake Valve springs was broken on #2 and there was evidence of #8 running hot and to a lesser degree #4. Low Compression on #8 was Blow by.

Fortunately other than knocking the Roller Finger Follower out of place, there was no spring failure related damage.

Interesting about the valve! Very fortunate you caught it early enough! Any plans for the #8 cooling?
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
4,008
1,924
Exp. Type
W2W Racing
Exp. Level
10-20 Years
Cookeville TN
I'm going to look the engine over. Apparently there are signs of erosion from pre-ignition on #8.

I'm contemplating the MMR cooling loop and maybe modifying the tune to richen up #8 a little.
Good to hear damage was not too severe Nick. Re ring, new PAC springs and new bearings the plan? Richening up #8 is a great idea, you should also look at a 93 octane tune since you run restrictor anyway. You could still mix 100 in there and save a few bucks each event. Hope to see you soon. Steve
 
Good to hear damage was not too severe Nick. Re ring, new PAC springs and new bearings the plan? Richening up #8 is a great idea, you should also look at a 93 octane tune since you run restrictor anyway. You could still mix 100 in there and save a few bucks each event. Hope to see you soon. Steve
I'm doing Pistons, Rings, Bearings, Valves, Valve seals & retainers. Block will get touch honed and the crank polished. Plus while it's apart the timing chains (they were off the FPC and have done 90 hours) and upgrading the secondary chain guides to: M-6207-M52.
Look forward to seeing you at the Track soon, Steve!
 

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