My engine build thread (NEW PICTURES)

[turtle5353]

t is a forged scat crank provided by MME racing after it was modified to a zero imbalance crank. I'm not sure how out of spec it is, but will know more tonight or tomorrow. While the machinist I am using said he can't correct it, it is possible that it is correctable-I have a couple of options I have to follow up on.

The machinist I am using is used to building race engines and says it would probably be fine since I am not building a 8000+ RPM engine-still I want to fully flesh out my options before I move forward.

Yeah i would definately talk to MME and scat. They should be able to care of you. I got my crank for my 408 build from scat and was very happey with it. Although i did not go with the 0 imbalance. Scat sent me a flex plate and damper that they balanced my rotating assembly with. Good luck!!! Keep us posted.

 

[Jeff73Mach1]

It is all worked out. The thrust bearing surface has runout that while within spec was not perfect. When assembled with the ARP main studs, the improved cap alignment made the .0015 of runout insignificant. I might need to slightly sand the face of my thrust bearings to get ideal endplay, but it does not appear to be an issue and is likely present in most Scat cranks.

Block and crank are home, Block is mounted on the engine stand and needs another thorough soap and water cleaning and blowing out to make sure it is totally **** and span before I bring it in to begin the next round of dry fitting. I think it is going to sit until the weekend-this week is friggin killing me!

 

[wwhite72]

Did you have the grinding work done on the main saddles where cracking sometimes ocurs? I saw pics of the technique. Never had it done on mine, but im not spinning to 6k.

 

[Jeff73Mach1]

Shhhhh! there are some secrets we should keep!

I had the mains line bored and inspected for cracks. The reason I went to an internally balanced crank was partially for the ability to spin to 7000 rpms when I was in a mood, and more because of the greatly improved harmonics of not having an imbalance at each end of the crank flexing it (which is what I understand cracks the saddles)

 

[Jeff73Mach1]

I managed to fit the crank, this time with all clearances checking out on the mains and the rods-installed the cam, clearances all around looked good-piston to valve clearance was .075 without a head gasket and with zero valve lash, so I am very pleased. No need to clearance anything-tons of room. All the holes are chased and main studs in place and half the head studs, but I ran out of steam for the day. Tomorrow I may start filing piston rings and move forward with more assembly.

On the downside-my Rocker arm geometry is way off and I need studs that are at least 7/16th of an inch longer and with the stud girdle I'm probably going to need different valve covers too.

 

[Jeff73Mach1]

Crap!

MME Racing sent me the wrong oil control rings!

I am back at a standstill after file fitting one top ring and one second ring

 

[Jeff73Mach1]

New oil rings are en route- Mark was very quick to take care of it. top and second rings were right so they are all now file fit. this was my first time file fitting rings and of the 16 I hit 14 dead nuts on and 2 top rings are at .018 rather than my target of .016 My bores were all too close in size to measure any difference, so I set one of the slightly looser rings on #2 and the other on #7. I believe I could open all up to .018 without ill effect and am currently considering doing just that. All the second rings are cut to .020 to prevent gasses from making it past the top rig and not being able to get out and causing ring flutter.

Good news or bad, I'm on hold until those oil rings arrive.

New ARP rocker arm studs came in and they look like they are going to work perfectly as does the Jomar Stud girdle. Looking forward to seeing if any of my valve covers will fit. If not I'll have two nice sets for sale.

 

[Jeff73Mach1]

Okay, next update

ARP rocker arm studs are installed and look good.

Oil control rings arrived and are installed.

All the pistons have been hung on the rods. This was my first time using circlips to retain pistons-very cool, but a bit finicky to install.

Next I will begin to install the pistons and rods over the next few days and go ahead and degree the cam and recheck valve clearances if I run it anything other than straight up.

My sons are on the same soccer team and are playing tonight for the division championship after a 2-1 win last night in the semi finals. I think they won the season outright as well. Obviously that is more important than an engine build, so it will be a few days before I get time to wrench.

I might have a few new pictures this weekend as I start assembling and making more of my final checks.

 

[droptop73]

Nice work Jeff

 

[Jeff73Mach1]

We can only hope! Thanks

My boys team won the tournament with a stout defensive showing winning Monday in a 2-1 defensive battle and Tuesday in a 1-0 shutout. Both play defense, though the younger (Josh) also played a 1/2 game of offense.

They did awesome and made the clutch plays all year. If anyone is a high powered booster to a college with a need for soccer players, I'll say it now, I am open to bribes, payoff etc to deliver these two to your program.

 

[73vertproject]

Finally got a chance to catch up on your thread, Jeff. Good stuff all around. Should be a good weekend for wrenching.

 

[Jeff73Mach1]

Well tonight was about 85% successful. I managed to get all but one piston installed cleanly, but #7 was a failure and I mangled the oil control rings. Piston and block are fine, but I'll be hard pressed to find a replacement tomorrow. I have a couple of places to check, but otherwise it went well. It takes very little effort to turn the crank. With my torque wrench set as low as it will go, it still turned it without clicking. Clearances all look perfect, so a oil control ring isn't too upsetting.

If I can get the last piston in tomorrow, I'll share some pictures. If not, I might anyway.

 

[Jeff73Mach1]

I took a few pictures today after I installed the timing gear and chain and while I was verifying cam timing.

I used the intake lobe centerline method with a proform degree wheel and a dial indicator. To do it properly it would have been better to have a different attaching method, but since I didn't I just wrapped the ARP Balancer bolt with electrical tape and secured the degree wheel like a sandwich. I used a locating dowel as my pointer and found peak opening of the intake and .050 before and after. I came up with 105 and the centerline is supposed to be 106, so I'm installed 5 degrees advanced rather than the 6 degrees ground into the cam. I have an offset key that would correct it, but I suspect my measurements accuracy is no greater than 1 degree so I'm going to call it good.

On the downside-I'm coming up with a compression ration calculation of 11.5:1 which is a full half point more than I had hoped for.

My quench height is .47 which should be perfect. I will get my replacement rings for #7 around Wen or Thursday so I'm back on hold-but I think it is an afternoon's work from here if I don't have any other (mostly self created) issues

so here are the pictures

 

[TommyK]

I took a few pictures today after I installed the timing gear and chain and while I was verifying cam timing.

I used the intake lobe centerline method with a proform degree wheel and a dial indicator. To do it properly it would have been better to have a different attaching method, but since I didn't I just wrapped the ARP Balancer bolt with electrical tape and secured the degree wheel like a sandwich. I used a locating dowel as my pointer and found peak opening of the intake and .050 before and after. I came up with 105 and the centerline is supposed to be 106, so I'm installed 5 degrees advanced rather than the 6 degrees ground into the cam. I have an offset key that would correct it, but I suspect my measurements accuracy is no greater than 1 degree so I'm going to call it good.

On the downside-I'm coming up with a compression ration calculation of 11.5:1 which is a full half point more than I had hoped for.

My quench height is .47 which should be perfect. I will get my replacement rings for #7 around Wen or Thursday so I'm back on hold-but I think it is an afternoon's work from here if I don't have any other (mostly self created) issues

so here are the pictures

Did you cc a chamber or are you using nominal values to calculate compression?

Maybe consider doing a little valve unshrouding which will help performance and increase chamber volume.

 

[Jeff73Mach1]

I cc'ed a chamber.

11.5 to 1 isn't unmanageable as I have access to race gas to tune up my street gas. I also have a set of OC 4V heads that I could build with my existing parts that would drop compression 3/4 of a point or so. I'm going to move forward as is, if I have problems, it isn't like I can't change heads.

a mild tune will help too, as my horsepower levels are going to seriously overtax my traction, anyway.

 

[JamesS]

What about copper head gasket? They can be used to pull back compression

 

[Jeff73Mach1]

Yes I considered that, but the copper head gaskets require the heads or the block to be o-ringed. The bigger problem is quench distance right now I have a nearly perfect quench distance of .047 with the standard .041 head gasket. Anything over .060 starts to be less efficient at preventing pinging. I'd rather try my luck with a perfect quench distance rather than screw that up in the name of reducing compression a quarter point.

 

[Tubo]

Jeff, when I realized my 331 intended for "street" duty & gas, was going to have a CR close to 11.0:1. The best alternative came in using a cam grind to help bleed off some of the dynamic CR. Lunati suggessted a VooDoo grind with 9d more exhaust than intake. So the moderate 221-229, I use lets me run 89 octane with 10:7 CR. The Coyote 5.0 VVT program changes the Mustang 11.1CR to 10.5 in the truck.

Long winded way of reccommending you get with your favorite cam grinder to "relieve" your CR issues.

Tubo

 

[Jeff73Mach1]

I don't have any issues at this time. Static compression ratios don't scare me, they are just numbers. If I have to dial back ignition timing a bit or add some extra 110 to the tank I will. The bigger problem with needing super duper premium comes when you travel and right now that isn't an issue.

I have joked with a few folks that I was going to build this engine at 14:1 and run it on E-85.

 

[caspianwendell]

Getting closer to a start date :banana: