Contemplating 5.0L rebuild for mild performance boost

[Mesozoic]

BTW, I did encounter a small snag. This is typical with aftermarket high performance stuff. The flexplate in use is not the OEM unit anymore, but this PRW unit that's SFI rated and quite a bit thicker than stock. The torque converter is also not OEM anymore, but a custom built unit (as all of them are) from Precision of New Hampton. The new converter does not have studs for connection to the flexplate, but comes with some 3/8" fine thread cap screws (and no washers).

The flexplate's holes do not align precisely with the converter's bolt hole pattern. This required slotting the holes in the flexplate so that they would accomodate the fine threaded bolts provided in the converter kit. I used a pneumatic die grinder with a 3/8" carbide bit with flat top, so if contact was made with the torque converter it was relatively inconsequential. Once that was done and cleaned up (3 of the holes required minor slotting), everything went together nicely. Something to keep in mind that it may be a distinct possibility when upgrading parts.

 

[CDW6212R]

Good fine detail work, that is a common thing with non OEM converters etc. I hope the play between the engine and torque converter was adequate, it needs that to keep pressure off of the thrust bearing.

 

[410Fortune]

Interesting! Would have been awesome to
Mate the converter to flexplate outside if the truck eh?

 

[C420sailor]

Is it easier to stab that way? I did it the way OP did…wasn’t toooooo much of a PITA

 

[410Fortune]

I mean it would be nice to know the holes don’t line up and needed machining before it was all in the truck
Now I know if I ever use aftermarket converter and flexplate to check things out outside the truck

 

[Turdle]

BTW, I did encounter a small snag. This is typical with aftermarket high performance stuff. The flexplate in use is not the OEM unit anymore, but this PRW unit that's SFI rated and quite a bit thicker than stock. The torque converter is also not OEM anymore, but a custom built unit (as all of them are) from Precision of New Hampton. The new converter does not have studs for connection to the flexplate, but comes with some 3/8" fine thread cap screws (and no washers).

The flexplate's holes do not align precisely with the converter's bolt hole pattern. This required slotting the holes in the flexplate so that they would accomodate the fine threaded bolts provided in the converter kit. I used a pneumatic die grinder with a 3/8" carbide bit with flat top, so if contact was made with the torque converter it was relatively inconsequential. Once that was done and cleaned up (3 of the holes required minor slotting), everything went together nicely. Something to keep in mind that it may be a distinct possibility when upgrading parts.

View attachment 449175

3 of 4 holes slotted worries me. Something will not spin true.

I see an sfi certification. You cannot alter and retain that

Need to find which is wrong. The holes should line up. Never, ever have I heard of such a thing as altering flex plate holes to accept a converter

 

[410Fortune]

I was thinking that too. Could it be lined up to the wrong holes? Factory
Flex plates have lots of holes in them
I would check the converter to flexplate fit outside of the truck

 

[Mesozoic]

The fuel tank has been upgraded. I had a Holley 190 lph pump for Fox Mustang sitting on the shelf, but it was connectorized differently than the stock pump. I ordered a new connector and sockets from Ballenger Motorsports (as I often have before for these types of projects) and sorted that out. The rubber damper bit that is keyed to the OEM pump had to be modified - I cut the bottom out of it to fit the Holley pump, taking note of the enforced orientation of the fuel sock. It's all back together and looking good! The pump itself is actually just a rebadged Walbro GSL unit.

My friend who rebuilt the transmission reminded me yesterday that he noticed something unusual about the aftermarket transmission temperature sending unit that was installed in it (the previous owner of my vehicle had done this). The port that the sending unit was plugged into (driver side front) interfered with one of the internal accumulator seals and had sliced it. For this reason, I removed the sending unit and plugged it with an aluminum 1/8" NPT plug, drilled a new hole in the side of the TCI pan, tapped it and installed the sensor there instead. He also mentioned that the original location the sensor was installed in wasn't ideal for temperature measurement because being the top of an accumulator, there is little to no circulation of fluid unless it was actuated; the pan being the far more ideal location for average temperature measurement based on the constant fluid flow.

 

[Mesozoic]

Regarding the flexplate, I've had to perform minor adjustments to aftermarket plates and converters many times. I had a fairly wild combination in a '71 Mustang at one point and the modifications were extensive enough that I had to machine something on it. Honestly, my biggest concern with modifying the plate in this instance was the fact that the rotating assembly was balanced using it in its factory state, not with my slotting adjustments.

The plate itself is quite a bit thicker than stock and the misalignment of the holes in the plate only required clearancing about 1/16" from 3 holes to accommodate the bolts, so I'm not too concerned about it. The alignment of the torque converter to the crank is important and that is maintained by the crank itself. The extra thickness of the plate is what I believe caused the problem. Even so, I used hardened washers behind the cap screws for fastening the plate to the converter and things look pretty good now. You're right about the SFI rating out the door - not that I need it!

 

[CDW6212R]

Well done, the details make the final combination either great or mediocre. I haven't yet hunted for an SFI balancer to build my final engine yet. That will require some modifications to mount a trigger wheel, the SFI is about testing the part for reliability at very high rpm's. When I get to cutting off the one ear of my engine block, to accommodate the 6R80 trans, then I'll be discussing the strength left with just five bolts holding the block to trans. It's the "fun stuff" we do to make the final result work really well.

Keep going.

 

[Mesozoic]

Not sure if this would help since it’s not SFI rated, but I’m running this damper from Powerbond which is a direct replacement for the OEM unit.

PowerBond PB1463ST PowerBond Street Performance Harmonic Balancers | Summit Racing

Free Shipping - PowerBond Street Performance Harmonic Balancers with qualifying orders of $109. Shop Harmonic Balancers at Summit Racing.

www.summitracing.com

 

[CDW6212R]

That might be the one I put on my black 98 truck, a very nice part.

Powerbond is about the best replacement brand, both stock and some upgrades. They do have some SFI, but for a stroker nobody makes a SBF unit with a trigger wheel, and 28oz(or zero). For the 337 I'm planning I want it to be zero balanced, and shift at 6k most likely. If I build the Cleveland I want, with the Explorer front dress etc, it'll shift close to 7k. Balancers are another odd puzzle piece to deal with on a highly modified combination.

 

[Blown]

A little hairy but I get it. The flexplate indexed with the crank utilizing the center hole, not the bolts.

 

[Mesozoic]

If anyone has close up pictures of the exhaust mounting bracket nearest the transmission passenger side, I could use a little help!

 

[410Fortune]

The exhaust hanger that mounts to the transmission mount bolt? I’m sure I have some pics of that

 

[donalds]

Found on Google

 

[Mesozoic]

Thanks folks, you're all life savers!

 

[410Fortune]

that is not the v8 mount

 

[410Fortune]

trying to find a better pic of the dual exhaust hanger mount assembly

 

[Mesozoic]

That is true, but I think the concept is clear. The V8 mounts adds another triangular rubber isolator bit stacked on top of the other, but I'm a fool for not taking a photo of that prior to dismantling it.

The renderings in the service manual aren't very easy for me to interpret sometimes, not sure if it's because they lack color or detail or that I'm just tired at the end of the day...