5.2A block GEN2 (GT500) comparison for 5.2XSv2.0 build

[OCPONY]

Here is a comparison of the Gen 1 and Gen 2 5.2 blocks. I have both on hand at the moment. I will be shipping the Gen 1 back by end of week so if anybody wants any specific differences that I don't cover then just post up.

So now it is time for "whats different in these pics"

I am hoping this link to my smugmug account works! It has all the pics I have taken so far.

https://aceone.smugmug.com/52XSv20/n-cV59vC/

Gen 2 is one to 1.5 pounds heavier.
The valley area is lower and flat compared to the gen 1 valley that is slightly humped. Makes the cross rib supports stand out more but really the "floor" is lower.

The lower drilled cooling ports between the cylinders are modified with a corresponding modification in the heads for "improved" cooling ? There are small triangles between cylinder bores where they drill a cooling port between the bores.

The air port into the rear bearing cover is more restricted?? smaller oval and not opened on the bottom side of the hole toward the top of the bearing cap.

The head bolts holes are 128 mm deep as opposed to the 71mm deep threads for the headbolts. This will affect cylinder bore diameter/taper with/without deckplates. I am checking bores now for custom pistons.

 

[VoodooBoss]

Great photos and thanks for posting.

 

[JAJ]

Here is a comparison of the Gen 1 and Gen 2 5.2 blocks. I have both on hand at the moment. I will be shipping the Gen 1 back by end of week so if anybody wants any specific differences that I don't cover then just post up.

So now it is time for "whats different in these pics"

I am hoping this link to my smugmug account works! It has all the pics I have taken so far.

Gen 2 is one to 1.5 pounds heavier.
The valley area is lower and flat compared to the gen 1 valley that is slightly humped. Makes the cross rib supports stand out more but really the "floor" is lower.

The lower drilled cooling ports between the cylinders are modified with a corresponding modification in the heads for "improved" cooling ? There are small triangles between cylinder bores where they drill a cooling port between the bores.

The air port into the rear bearing cover is more restricted?? smaller oval and not opened on the bottom side of the hole toward the top of the bearing cap.

The head bolts holes are 128 mm deep as opposed to the 71mm deep threads for the headbolts. This will affect cylinder bore diameter/taper with/without deckplates. I am checking bores now for custom pistons.

Very interesting! It looks too like the Gen 2 block has fittings for 4 knock sensors as well as the usual 2.

 

[bauern]

The lower drilled cooling ports between the cylinders are modified with a corresponding modification in the heads for "improved" cooling ? There are small triangles between cylinder bores where they drill a cooling port between the bores.

Curious to see if there is a change in the head gasket. If there is an open "V" that spans the vent hole and the water passage, then the "old" heads (not sure if there is a change in the heads) would work with the new block.

Have you ordered new heads/head gaskets?

 

[OCPONY]

Curious to see if there is a change in the head gasket. If there is an open "V" that spans the vent hole and the water passage, then the "old" heads (not sure if there is a change in the heads) would work with the new block.

Have you ordered new heads/head gaskets?

The engineer said it will require new gaskets. I don't have them yet, only the longer head bolts. They weren't available when I orders stuff earlier but may be now. I am just using the Gen 1 gaskets for now for pre-assembly measurements. The heads are changed also. I have the new heads they have a deeper triangle there. I believe you can just tweak the older heads by opening up the triangle some with a dremel if you go to the newer block.

 

[OCPONY]

Very interesting! It looks too like the Gen 2 block has fittings for 4 knock sensors as well as the usual 2.

Nice catch! I totally missed that. That looks like where some of the extra weight came in since it has six posts instead of just the two.

 

[OCPONY]

I will say the casting flash in the oil passages is much better than it was on my first block. i spent lots of time cleaning them out but then look decent. I will still smooth these up some and there is one that has a mounting boss located under it that I grind off too to help the flow into the side ports of the windage tray.

 

[OCPONY]

Great photos and thanks for posting.

Sure thing. I will have lots more as I build this one. The first one was built a month before SEMA 2016 as the first available 5.2 heads got to me finally around Oct 8th iirc. I couldn't even get the proper 5.2 assembly instructions at that time from any of my local guys with access and hard to reach out to folks at midnight and weekends!

 

[OCPONY]

I added some more details about the cooling ports and close up pics. As I add image they are available at the original smugmug link in post 1.

 

[captdistraction]

ugh, if I wasn't so far into my build I'd have really considered this. The only fear is the non-serviceable liner and if it can take a torque plate hone (because made/machined in detroit with love and derp). Very curious to see how this beast measures out!

 

[bauern]

ugh, if I wasn't so far into my build I'd have really considered this. The only fear is the non-serviceable liner and if it can take a torque plate hone (because made/machined in detroit with love and derp). Very curious to see how this beast measures out!

The Voodoo block is supposedly torque plate honed by the factory.

 

[captdistraction]

The Voodoo block is supposedly torque plate honed by the factory.

Goes without saying to check that. I was told the same for the production “finish machined” blocks but found that to not be the case.


Sent from my iPhone using Tapatalk

 

[OCPONY]

Goes without saying to check that. I was told the same for the production “finish machined” blocks but found that to not be the case.


Sent from my iPhone using Tapatalk

So far it is pretty good. max taper/out of round has been .0008 with most at .0006. I can't precisely check for bore center to center like on a digital measuring CNC machine. But for my needs I just concerned out individual cylinder specs.

Caveats:
I have a 2 in aluminum torque plate and used the OEM long bolts torqued to 90 ft lbs. I didn't do the final 90* to put the bolts in yield though. I used spacers on the torque plates to make sure the bolts are within one thread width of being in installed depth.

I did just purchase a new Fowler standard stand. First time I have used it. Set it with temperature at 72 ambient temperature and block also measured at 72* ambient.
I did get repeatable results on the Bore gauge too so I'm pretty confident in these dimensions. I typically triple check for repeatable measurements before proceeding to take lots of measurements. I also go back and check previously recorded measurements at various times as I'm doing different measurements.

Results:

I detected more out of round variation in the top half of cylinders than I did on the bottom which should be due to the threads (at bottom) holding the cylinders in the same shape as when factory honed. The thrust axis was also .0003 larger on average than the non thrust axis. I'm not sure of that reason though. Not on all cylinders and also on the top half of cylinders. By the way the bolts are threaded well over half the length the bolts. Many more threads then on an ARP bolt. I will give exact measurements later as I didn't take notes of the bolt dimensions.


Bottom of cylinders were average of 3.6992 +/- .0001.
Top of cylinders average of 8 cylinders of 3.6993875 +/- .0002. On non-thrust axis, and 3.6996625 +/- .0002 on the thrust axis: Four were 3.6997 with two at 3.6998 and one 3.6995 and one 3.6994.

Took middle measurements also. So six per cylinder and looked for max variations which occurred in the top third of the cylinders.

 

[OCPONY]

ugh, if I wasn't so far into my build I'd have really considered this. The only fear is the non-serviceable liner and if it can take a torque plate hone (because made/machined in detroit with love and derp). Very curious to see how this beast measures out!

According to the Ford engineer you can hone it but not to exceed 3.70136" So you can probably get one light honing out of the block. So far these blocks I have used are fine and new are still cheaper than having a block sleaved. Sleaves are what $1000 to 1200 plus the machining that is around $ 2 thousand??. New 5.2 Gen 1 block was $2100 and Gen 2 was $2400 ish. Don't have my bill handy.