A military rebuilt 6.5

[n8in8or]

Nice work Nate. Personally, I like using the carbide cutters like your using there I think. Then I have a set of all different sizes, lengths, and grits of drum sanding rolls. They work amazing for smoothing, and polishing. I guess I never thought about spending much time porting on a 6.5, but maybe I should, especially if I want to try keeping your Tahoe!
That exaust valve seat you have pictured must have been in the open postion while that engine was sitting, as it looks a bit ruff, but I'm sure nothing a good valve lap wouldn't take care of. Loving the updates.

Matt

Ok, I just ordered an assortment of rolls and mandrels from Summit. Thanks for the suggestion Matt, that looks like just what I needed to get these where I want them Usually I receive it the next day from them since their warehouse is close. I'm really hoping to get the heads all finished this weekend so I can take them to the machine shop to have them cleaned really well - gotta get the last of that coolant nastiness out of there. Hopefully they'll be done honing the block soon so I can start file-fitting rings.

 

[SS FORCE]

Thanks SS, I am having fun. Yeah it sounds like there are a few of you in that part of the country that would be fun to hang with....I may have to drive the fat girl down that direction sometime

You are welcome to come crash at the residence any time. Always fun to talk truck or lend a hand, or have a hand lent to you. It's nice having fellow 6.5'ers in the area. We gotta stick together. Keep the updates coming it's looking great.

Bring your fat girl down and we'll make her look like a lightweight next to ol BigRedd.

 

[n8in8or]

Ok the heads are all ported and the valves are lapped. I did end up getting a sanding roll assortment from Summit and it worked nice. Now I didn't work the ports as well as a pro would, but they're a ton better than they were and they're not bad for the time invested in them. It wasn't my goal to make them flow every single cfm they're capable of anyway, it just seemed like a good thing to do whike they were apart. It surprised me how much of a step was present under the valve seat before. Tomorrow they go to the machine shop for a good cleaning.

 

[Will L.]

Have you ever tried unshrouding the heads on a 6.5? I know unshrouding in any gasser yields way more results than porting.

 

[n8in8or]

Have you ever tried unshrouding the heads on a 6.5? I know unshrouding in any gasser yields way more results than porting.

I initially thought about doing that, but when I researched it, I wasn't too sure it was a good idea. It sounds like it would affect my compression ratio a lot. As I looked at it closer, I noticed that the angle of the relief around the valve was the same angle as the seat - so while it might help a little laying that angle back, I was worried that it would affect my compression too much. Plus, it was also tempting fate a bunch more in that I could easily see myself knicking a seat trying to lay those back. My dad has given me a valve grinder, so I had thought that I could use that to lay those back, but it isn't at my house yet and I've never operated one before, so I didn't really want to do a bunch of experimenting on these Optimizer heads. I'll leave that to my random SBC heads I have lying around

Maybe someday I'll get ambitious and try a set relieved and not relieved to see how it affects things.

 

[FellowTraveler]

Nice work/ how soon you think it will be together?

 

[Will L.]

The trick for the valve seat is to drop in a couple old valves to protect it from the oopsy-daisies. As for the loss in compression on a deck head(like the 6.5), way less difference than when everyone is adding the +.010 head gaskets. I would take out the material and use standard thickness gaskets. My 2 pennies...

 

[n8in8or]

Nice work/ how soon you think it will be together?

Thanks. I should have the block back next week so then I can file fit the rings and assemble the short block. I sent my precups to a guy to be machined to diamond specs and he may not have that done for a couple weeks, so that's a driver of my time. And then I'm going to have the transmission rebuilt while the engine is out so I need tax money for that....so long story short (too late) hopefully things will really be happening in 2 to 3 weeks.

 

[n8in8or]

The trick for the valve seat is to drop in a couple old valves to protect it from the oopsy-daisies. As for the loss in compression on a deck head(like the 6.5), way less difference than when everyone is adding the +.010 head gaskets. I would take out the material and use standard thickness gaskets. My 2 pennies...

I haven't done the math, but it sounds reasonable. At this point I've done all I want with these heads. I would love playing even more with one of these someday.

 

[Jorge6.5]

Thanks. I should have the block back next week so then I can file fit the rings and assemble the short block. I sent my precups to a guy to be machined to diamond specs and he may not have that done for a couple weeks, so that's a driver of my time. And then I'm going to have the transmission rebuilt while the engine is out so I need tax money for that....so long story short (too late) hopefully things will really be happening in 2 to 3 weeks.

Get your self a bilett piston torque converter from transgo.

 

[bowtiebutler956]

Very nice work your doing there Nate! I'll probably be doing a little porting myself here soon, as the pics of the China heads I just ordered look worse than the OE heads down in the pockets. Thats going to be one sweet 6.5, and I'm looking forward to the next update.

Matt

 

[n8in8or]

I can't wait to see what you come up with for yours. It will be cool too because you can do a real before and after comparison.

 

[n8in8or]

Get your self a bilett piston torque converter from transgo.

I think I'm going to go with a heavy duty billet Precision torque converter.

 

[bowtiebutler956]

I can't wait to see what you come up with for yours. It will be cool too because you can do a real before and after comparison.

Nate it's obvious you put some real time into your heads, and they should flow very well. I probably won't go quite as far as you did. I have several times in the past on my hotrods, but I don't believe I would see as much gain as I did on those NA engines. Although I'm sure there will be worthwhile gains. Who know, once I start, I may have to go all the way.

Matt

 

[n8in8or]

Nate it's obvious you put some real time into your heads, and they should flow very well. I probably won't go quite as far as you did. I have several times in the past on my hotrods, but I don't believe I would see as much gain as I did on those NA engines. Although I'm sure there will be worthwhile gains. Who know, once I start, I may have to go all the way.

Matt

I have about 8 hours into them at this point, which seemed reasonable for what I'm doing. I could spend a lot more time with sanding rolls and trying unshrouding the valves like Will suggested but I feel good with what I've done here. I also didn't want to take too much material off and make them think about cracking.

 

[FellowTraveler]

Triple disk billet converter is nice just remember if they can trim the torque multiplication the more the better as stall goes I'd stay low for a daily driver diesel. I see you are going with a transmission rebuild are they doing all the sonnex updates too, or? I've had great results with AMSOIL full synthetic trans fluid "best ever."

 

[FellowTraveler]

Very nice work your doing there Nate! I'll probably be doing a little porting myself here soon, as the pics of the China heads I just ordered look worse than the OE heads down in the pockets. Thats going to be one sweet 6.5, and I'm looking forward to the next update.

Matt

Thats a good idea the porting!

 

[n8in8or]

Triple disk billet converter is nice just remember if they can trim the torque multiplication the more the better as stall goes I'd stay low for a daily driver diesel. I see you are going with a transmission rebuild are they doing all the sonnex updates too, or? I've had great results with AMSOIL full synthetic trans fluid "best ever."

I'm not sure about the torque multiplication of it. They do offer a lower than stock stall speed, but when I talked to Delta about their cam grind that I'm getting they recommended sticking with stock stall speed.

As far as the Sonnax updates, I put in a rebuilt valve body last year that supposedly has all the uodates, but my rebuilder said he would verify they're in there when he has it apart and if they're not there he'd put them in. There's also an update for the pump so he's going to do that too for me.

 

[bowtiebutler956]

I'm not sure about the torque multiplication of it. They do offer a lower than stock stall speed, but when I talked to Delta about their cam grind that I'm getting they recommended sticking with stock stall speed.

As far as the Sonnax updates, I put in a rebuilt valve body last year that supposedly has all the uodates, but my rebuilder said he would verify they're in there when he has it apart and if they're not there he'd put them in. There's also an update for the pump so he's going to do that too for me.

Wow, your using a Delta cam as well. Which grind? They offer 2 different ones, don't they?

Matt

 

[n8in8or]

Wow, your using a Delta cam as well. Which grind? They offer 2 different ones, don't they?

Matt

They just received my core Friday so I need to call them today to confirm the details. When I talked to them last week they told me they only had one grind, so I asked about the 202 and the 206 and they said they only offer the 202 now because there were valve to piston clearance issues with the 206. They can still make the 206 but they don't consider it a bolt in so they don't really advertise it. They said you have to cut valve reliefs in the pistons to use it. So sounds like I'll be going with the 202.