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My motor blew up......now what?

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Make double sure you don't have a bent valve when you re use the old heads
I bought a valve spring compressor for the Coyote head so I will definitely be confirming this shortly. Steve (2012-Boss) hooked me up with a great resource for Coyote cylinder heads (Slawko Racing Heads) that is only 15 min from my home. Never even knew they existed. I will have them clean up the heads and replace any valves if needed. If funds permit I'll do some work on them as well. I'm learning on the fly here!
 
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I bought a valve spring compressor for the Coyote head so I will definitely be confirming this shortly. Steve (2012-Boss) hooked me up with a great resource for Coyote cylinder heads (Slawko Racing Heads) that is only 15 min from my home. Never even knew they existed. I will have them clean up the heads and replace any valves if needed. If funds permit I'll do some work on them as well. I'm learning on the fly here!
I'm sure they will tell you this, but a slight back cut on the stem side of the valve will increase flow quite a bit. Back in the day it was called a 3 angle valve job, a 60 on the bottom of the valve, a 45 on the face of the valve and a 30 on the top (or in reverse, depending on how you look at it). Same with the head side.
 
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I bought a valve spring compressor for the Coyote head so I will definitely be confirming this shortly. Steve (2012-Boss) hooked me up with a great resource for Coyote cylinder heads (Slawko Racing Heads) that is only 15 min from my home. Never even knew they existed. I will have them clean up the heads and replace any valves if needed. If funds permit I'll do some work on them as well. I'm learning on the fly here!
Doc,

If you decide to have larger valves or any additional port work done to your Boss heads, make sure they know that this is a road race engine. You don't want any loss of mid-range torque (i.e. no torque loss at 3500 RPM). You need the mid-range torque at corner exit. If they get to aggressive with the port work to maximize high rpm power gain you can loose a lot of mid-range torque. This works fine for drag racing, but not for road racing.
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Doc,

If you decide to have larger valves or any additional port work done to your Boss heads, make sure they know that this is a road race engine. You don't want any loss of mid-range torque (i.e. no torque loss at 3500 RPM). You need the mid-range torque at corner exit. If they get to aggressive with the port work to maximize high rpm power gain you can loose a lot of mid-range torque. This works fine for drag racing, but not for road racing.
Exactly.
 
@Fabman........how has your experience with E85 been? I'm planning to switch to VP Racing E85 so no issues with purity. My major concern is hygroscopicity. My car will sit for 5-6 months in an unheated garage. I'm guessing I can drain the stock tank each season but should I be concerned about corrosion in the engine?
Anything else I should know? My tuner is very familiar with E85 and is very positive on the idea. Bigger injectors will be needed. What about fuel pump??
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
@Fabman........how has your experience with E85 been? I'm planning to switch to VP Racing E85 so no issues with purity. My major concern is hygroscopicity. My car will sit for 5-6 months in an unheated garage. I'm guessing I can drain the stock tank each season but should I be concerned about corrosion in the engine?
Anything else I should know? My tuner is very familiar with E85 and is very positive on the idea. Bigger injectors will be needed. What about fuel pump??
I have been on e85 for years and years, no issues at all. Just be mindful.
Remember, its not the fuel that corrodes, its the water that's attracted to the fuel that corrodes.
Don't store fuel in plastic containers (except for transport to the track) or leave them open or unsealed and you will be fine. I store mine in 55 gal drums and keep them sealed tight. I started this last season on a drum I had stored for 3 years and it was fine. A stock gas tank should be sealed up for smog purposes so you should be good as long as there are no air leaks. For long term storage you can fill the tank with gasoline if you like and that will help wash out any moisture that may get in there when racing season starts back up.
I just use pump e85. Its cheap and effective. I have an electric e85 meter in the return line so I can monitor fuel in real time. Remember, when the fuel dips below 85% the mixture gets RICHER not Leaner...so you are not likely to burn things up providing you have some safety margin in your tune...and you should.
I have run fuel all the way down to 70% and have been okay though I try to stay as close to 85% as possible. I ran around to every station within 100 mile radius and sampled fuel from each. Now I buy from one source that always has a stable mix from 80 to 85% and its a little over 3 bucks a gallon....your mileage may vary.
 
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Don't store fuel in plastic containers (except for transport to the track) or leave them open or unsealed and you will be fine. I store mine in 55 gal drums and keep them sealed tight.
That's exactly how I do it now with the Sunoco 100. I actually put the drum in my trailer and would fill it at the track. I'll likely just keep the E85 drum in the trailer and fill a single fuel jug to get it in the car. Wish a local track had a race E85 pump so I could just fill the drum as needed. The VP depot isn't really that far away so it's not a big deal to grab a new drum.....other than the cost.
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
That's exactly how I do it now with the Sunoco 100. I actually put the drum in my trailer and would fill it at the track. I'll likely just keep the E85 drum in the trailer and fill a single fuel jug to get it in the car. Wish a local track had a race E85 pump so I could just fill the drum as needed. The VP depot isn't really that far away so it's not a big deal to grab a new drum.....other than the cost.
I go to the station with a bunch of jugs the day before a race and fill them up. I take those to the track and whatever fuel I don't use goes back into the drum. That way I don't have to drag a drum around.
 

Fabman

Dances with Racecars
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20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
FWIW back in the day a lot of kart racers ran alcohol, at the end of the day they would empty the tanks and run gasoline through the lines and engine (they actually used a 2 cycle oil/gas mix) to wash everything out.
Yeah, Alcohol (Methanol) is even more bothersome than Ethanol. Plus it burns your eyes and lungs.
Even when we were allowed to run it in Stock cars I never did because I couldn't stand the fumes.
e85 smells kinna good.
 
Have you been able to poke around through the pile of parts and get any idea of what caused the failure?
The #6 cylinder. The connecting rods are weak to begin with. Add in the oiling and cooling deficiencies in the Gen 1 block plus running to 7500 rpm consistently and it was probably a matter of time before mine detonated. The #6 rod broke.....rest of the cylinders were fine.
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
The #6 cylinder. The connecting rods are weak to begin with. Add in the oiling and cooling deficiencies in the Gen 1 block plus running to 7500 rpm consistently and it was probably a matter of time before mine detonated. The #6 rod broke.....rest of the cylinders were fine.
Pick up a gen 3 short block.
 
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The #6 cylinder. The connecting rods are weak to begin with. Add in the oiling and cooling deficiencies in the Gen 1 block plus running to 7500 rpm consistently and it was probably a matter of time before mine detonated. The #6 rod broke.....rest of the cylinders were fine.
on mine I think rod failure also. No heat marks under piston and didn’t look like detonation. The rest looked good.

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171
Exp. Type
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3-5 Years
Columbia, TN
Backorders suck.

I have a document from Ford showing the oiling and cooling passages of the Gen 1, and then another doc describing the evolution from 1 to 2 to 3, but nothing talks about Oiling and Cooling improvements. LMR has a great write-up, but I don't recall them elaborating on this either. I can see the Gen 3 head gasket has modest changes (which are usually all thats needed). Can you guys point me to where this info can be found?

Also, Gen 1/2 heads will bolt onto a Gen 3 short block... I thought the oil passage feeding the cams was different?
 
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Pick up a gen 3 short block.
The factory Gen 3 short block is a good piece. But, it uses the 2012 - 2013 Boss 302 sintered / powder metal forged connecting rods. If the OP is concerned about the strength of the OEM rods, he needs to use a set of Manley's or other aftermarket forged rod.
 
898
544
Backorders suck.

I have a document from Ford showing the oiling and cooling passages of the Gen 1, and then another doc describing the evolution from 1 to 2 to 3, but nothing talks about Oiling and Cooling improvements. LMR has a great write-up, but I don't recall them elaborating on this either. I can see the Gen 3 head gasket has modest changes (which are usually all thats needed). Can you guys point me to where this info can be found?

Also, Gen 1/2 heads will bolt onto a Gen 3 short block... I thought the oil passage feeding the cams was different?
You can put Gen 1 or 2 heads on a Gen 3 short block, but you need to use the corresponding head gasket. Gen 1 gaskets for Gen 1 heads, Gen 2 gaskets for Gen 2 heads and so on.
 

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