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Long, slow build of my truck

Figured it out, just as the OBD code told me, I had a bad connection on the coolant temp sensor in the crossover pipe. All better now. Gauges are next. Heath tune should arrive tomorrow.
 
Just did a 3mi loop with the Heath ECM and holy sh!t the thing is fast! Like a completely different truck. I told them to write it hot and they sure did! Nice thick cloud of smoke and then its 20psi in the blink of an eye. I have a set of gauges on order, including a 0-35psi boost gauge, this 0-20psi Sunpro from Advance isnt gonna cut it. Im gonna slap on an HX40 with a 16cm housing and see how it likes that. I think the 35 might be a hair on the small side.
 
Looks like same as mine. Electric or mechanical? If you need an adapter for mech fuel gauge let me know. I have a cool swivel flare to 1/8" npt fitting. Makes it easy to hook to standard hose kits.
 
Leroy, the boost is mechanical, EGT and fuel pressure are electric.

Had the truck on the highway tonight for the first time since I put the chip in... I am a little disappointed. I was not sure what to expect, but it does not feel like the same truck that rips around the back roads. Seat of the pants dyno reads noticeably lower. I am wondering if the HX35 is a little small. It spools fast, like GM turbo fast, and makes good boost. However, with TCC locked up, and rolling into it, I still do not see higher than 17-18psi. I would expect slightly higher. I know Heath preaches "healthy injection system", and I may or may not have that. The IP is reman from Pensacola Fuel Injection, which I have heard mixed reviews on. I have no idea of the mileage on the injectors, but at most it is 185k, so they are probably due. The feeling on the highway is similar to GM turbo with stock programming - chokes at a certain speed. I could get up to 80 pretty easily, but from there wasn't fun.

I am going to try the HX40 and see what's what.
 
pacificdrumma said:
Leroy, the boost is mechanical, EGT and fuel pressure are electric.

Had the truck on the highway tonight for the first time since I put the chip in... I am a little disappointed. I was not sure what to expect, but it does not feel like the same truck that rips around the back roads. Seat of the pants dyno reads noticeably lower. I am wondering if the HX35 is a little small. It spools fast, like GM turbo fast, and makes good boost. However, with TCC locked up, and rolling into it, I still do not see higher than 17-18psi. I would expect slightly higher. I know Heath preaches "healthy injection system", and I may or may not have that. The IP is reman from Pensacola Fuel Injection, which I have heard mixed reviews on. I have no idea of the mileage on the injectors, but at most it is 185k, so they are probably due. The feeling on the highway is similar to GM turbo with stock programming - chokes at a certain speed. I could get up to 80 pretty easily, but from there wasn't fun.

I am going to try the HX40 and see what's what.
Click to expand...

Remember with the HX40 your pumping lots more cfm at lower boost levels meaning you'll need more fuel period or the limit wall will show itself early on a hybrid HX35-40 would be about the same but with more back/drive pressure. A Bull Boose DB would be the way to go for more power but suspect anything older than a May 99 'enhanced' block may not be up to the task. Commonly rebuilders only rebuild the May 99 and newer 6.5's as the older ones just don't make $$$$ sense to do this is not to say there aren't some good old seasoned blocks out there for lower powered builds.
 
Do you know of any difference of the May 1999 506 engines compared to the earlier 506 engines?

I have heard that before, but I was under the impression that's because that is when new optimizer 6500 engine started being produced - it was getting put in all of the Hmmwvs before the year 2000. they started in May 1999, but the GM produced 506 continued beyond that for standard production. I think that timestamp was what most people considered the change over to the new good engine, not knowing there is a difference between the GM engine and the international engine.

Hopefully I am mistaken. If anyone knows the difference in the early to late 99 engines that makes it better, let me know please. I have 1999 506 in my garage, might have to go check out the month...
 
Will L. said:
Do you know of any difference of the May 1999 506 engines compared to the earlier 506 engines?

I have heard that before, but I was under the impression that's because that is when new optimizer 6500 engine started being produced - it was getting put in all of the Hmmwvs before the year 2000. they started in May 1999, but the GM produced 506 continued beyond that for standard production. I think that timestamp was what most people considered the change over to the new good engine, not knowing there is a difference between the GM engine and the international engine.

Hopefully I am mistaken. If anyone knows the difference in the early to late 99 engines that makes it better, let me know please. I have 1999 506 in my garage, might have to go check out the month...
Click to expand...

Will, the casting on the May 1999 blocks in GMT400 and newer are not GM manufactured and have lots more material around motor mount and accessory mounting pads, stepped mains, smaller cooling jets and identical in appearance to the optimizer 6500 AMG released however to the best of my knowledge date codes differ between the two. I should have some images archived that show the difference between the older crack prone 6.5td and the enhanced like I have in my 1999 Burb when I find them I'll post them up or just do new ones of my enhanced 6.5td.

Here is a good read on the topic: http://www.enginebuildermag.com/2007/06/the-optimizer-6500/
 
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When GM ceased production of the 6.5td in 1999 AM General supplied the enhanced 6.5 N/A & 6.5td td for GMT400 and van series for consumer and municipal/government contract/fleet vehicles up to 2002 if I remember correctly.
 
Cool thanks. I had to go look in my shop...

image.jpg image.jpg image.jpg

Incase these valley pics help anyone else. Out of a 99 gmc savanna van. I used the manifolds,turbo,injectors, camshaft from this. Definitely not optimizer parts anywhere on it.

That guy has some good info, but some incorrect. Double check his stuff if crucial.
 
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Will, what about the mains on that block any shots, is the block damaged or? There are stories that the center mount turbo blocks do suffer from some cooling issues but I have no idea about the actual facts on that.

All indications have GM stopping production of the 6.5 in March 1999 after creating the enhanced 6.5td which didn't get into the GMT400 line until May 1999 according to various stories, from here GM was focused on two things the new DuraMax and the Hummer Brand and all the GM tooling for the 6.5 was part of the trade w/AMG.

The May 1999 date maybe accurate as I've seen pre May 1999 GMT400 equipped with older version of the 6.5.

AM General apparently used older per enhanced 6.5 in later H1's and ate the big one on having to replace them.

The enhanced 6.5 blocks GM developed just before they abandoned the 6.5 were what went on to became the optimizer 6500 cast by NAVISTAR w/endless highway logo. Years ago I tried to get reliable info as to how many enhanced 6.5 blocks failed and found very few that were trashed because of lack of P/M and the rest didn't have the failures that the pre enhanced 6.5 were prone too.

Hopefully today I'll post images of my enhanced block.
 
Tied up for a bit on projects, it'll be a bit before I can open that up the rest of the way. It has about 70,000 miles on it, the van was frame damage that ended its life in Az. About the center mount turbo engines failing, there is more heat around the back 2 cylinders from the up pipes wrapping the back to the turbo, and to make it even better, the turbo exhaust goes down the #8 side. As soon as I finish my exhaust mods I am going to wrap in the pyrogel xtf secured with stainless screen to avoid that problem, or the "header wrap rust" issue. How much it really affects the engine idk.
 
Will L. said:
Tied up for a bit on projects, it'll be a bit before I can open that up the rest of the way. It has about 70,000 miles on it, the van was frame damage that ended its life in Az. About the center mount turbo engines failing, there is more heat around the back 2 cylinders from the up pipes wrapping the back to the turbo, and to make it even better, the turbo exhaust goes down the #8 side. As soon as I finish my exhaust mods I am going to wrap in the pyrogel xtf secured with stainless screen to avoid that problem, or the "header wrap rust" issue. How much it really affects the engine idk.
Click to expand...

Good job on that wrap, I suspect GM got it right w/enhanced 6.5's but dropped the line for what they thought were greener pastures we all seen the result of that.
 
Gauges are in, so far only boost and backlights are hooked up. Hope to have fuel pressure and egt done this week. Best way to get access to manifold is pull inner fender? I want to get to the flat spot under the turbo flange.

Also, looking to do some maintenance/upgrades to the cooling system. I know Heath's kit is basically a 97+ water pump. I have read that there are differences from 97-00 (00 is "balanced" and press on, 97 is 4 studs) what is consensus on which is best? Also, new t-stat, 195* AC Delco for that, and a radiator flush.

On a side note, I put the original 2-bar MAP sensor back in just for haha's... truck is definitely faster and more fuel (as evidenced by smoke) with the 3-bar MAP. Truck goes good, still not pleased with highway speed driving... but I will be happy if I can get it run cooler.
 
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