Engine rebuild probably coming this winter

[Strikeking10]

I recently got a new Gen2 TVS installed and made 568whp and 535 wtq at 19.5psi and 15* timing but I felt that I was down on some power so I had our Ford dealership here do a compression check and found that cylinders 5 and 6 were down to 135 and 145, so this winter im going to tear it all apart and more than likely upgrade the internals unless its such a simple fix that I dont really need too.

I was looking for opinions on what the best parts to use would be(rods pistons ect), I was looking at buying MMR's 900 or 1000 rotating assemblies and having my local performance shop build it, but I would like other options as well, or if my rods and crank are good to keep those and just get pistons and rings? Anything else I would need to upgrade in the heads at the same time, I will eventually be running E85 and maybe add nitrous next year also shooting for around 750/750 would be the goal

 

[s351]

Has your local shop built mod motors before?

 

[Derek@Lethal]

First, what were the other cylinders at compression wise?

Second, unless something really bad happened, like severe over heating and such, the stock crank and rods should still be good. If they are, I would reuse those and use Clevite performance coated bearings, ARP 2000 rod bolts and Manley pistons and rings. Throw in some main and head studs to seal it up and I think that would be a good base for your build. We have all of these parts available on our site and use them in some of our builds as well.

Let us know if you need help with anything else.

Thanks.

 

[Strikeking10]

Has your local shop built mod motors before?

First, what were the other cylinders at compression wise?

Second, unless something really bad happened, like severe over heating and such, the stock crank and rods should still be good. If they are, I would reuse those and use Clevite performance coated bearings, ARP 2000 rod bolts and Manley pistons and rings. Throw in some main and head studs to seal it up and I think that would be a good base for your build. We have all of these parts available on our site and use them in some of our builds as well.

Let us know if you need help with anything else.

Thanks.

I didnt ask them that in particular, I have a great friendship with them though and they've worked on everything from Honda's to gt500's with a couple Terminators also including mine, they installed my Tvs also.

Compression was
Dry ..........with Oil squirted in
#1 190....... 215
#2 170....... 215
#3 180....... 215
#4 185....... 210
#5 135....... 185
#6 145....... 195
#7 185....... 220
#8 180....... 220

 

[s351]

K, I was just checking that they have built some mod motors and you are not the guinea pig. As stated above if your rods and crank are good just reuse them, and upgrade the rod bolts.

 

[jrgoffin]

Here are the nicest mod motor pistons you can currently get right now - billet and completely custom for an incredible price:

http://www.modularfords.com/threads/231649-Off-The-Shelf-(OTS)-Custom-ModMotor-Pistons

Keep the stock rods and crank, upgrade to a lot of ARP fasteners, and get ready to spend a bunch of $$$$! Here's a build thread that will give you some information (aluminum block, but you'll get the idea):

http://www.modularfords.com/threads/236857-Aluminator-Gibtec-build

 

[Derek@Lethal]

I didnt ask them that in particular, I have a great friendship with them though and they've worked on everything from Honda's to gt500's with a couple Terminators also including mine, they installed my Tvs also.

Compression was
Dry ..........with Oil squirted in
#1 190....... 215
#2 170....... 215
#3 180....... 215
#4 185....... 210
#5 135....... 185
#6 145....... 195
#7 185....... 220
#8 180....... 220

Yeah, 15%+ difference is enough for me to want to look into fixing it up. Let us know if you need help with anything.

 

[Strikeking10]

Im kinda wanting to bump the compression up a little to something like 9.3:1 or something similar, What else in the heads should I upgrade while they are off the car?