dont let the oil cooler lines bite you

[Patrick m.]

If you are changing your engine, dont forget GM changed the oil cooler line size some time in the 96-98 year model range.
Not only will you need new oil cooler lines, you will need new oil cooler line adapters that screw into the block.
I had read this before but brain block kept me from realizing this is what i was headed for.
Anyway, my engine is re-assembled, with the 98 model block, 18-1 pistons, splayed mains, pistons ceramic coated tops, teflon coated sides, each cylinder bored to a specific piston, each rod honed to a specific pin, and crank journal. each set of rings sized to a specific cylinder. The crank has been straightened, polished, balanced and chamfered.
The block was align honed.
deck surfaced, cam bore was measured before align hone.
chain length set
rod small hole installed loose ( helps with high rpm motion)
Cyl head had coolant passage tubes installed, deck surface milled, all valves replaced, pre-cups enlarged.
All valve springs measured at full rest and fullopen, valve tip height adjusted accordingly.
port matched intake manifold, cyl head, and exhaust manifold
Painted the block semi gloss black, the heads aluminum, the valve covers semi gloss black, water pump semi gloss black, front cover aluminum, will post pics as soon as time permits

[john8662]

On your '98 block, which size outside main bolt holes did it have, large (like the 599 had) or smaller like the later 506's?

My '97 has the BIG outside bolt holes, just comparing...

Sounds great on the build!

Ran into the same thing on the cooler line size, mine was 1/2" NPT, so I just got screw in 1/2" NPT to 3/8" NPT adapters, works perfectly and doesn't stick out of the block more than 3/8" more than factory, putting this where a 6.2 was...

P.S. the lil T04B made the 6.2 run better!

J

[Patrick m.]

glad to hear it about the T04B!

I discovered today the oil cooler is different as well, should have known.
thats ok, at some point everything will be as a 98 model.

So far im disappointed with the power it has, but it has improved a little since first start-up. I let it run about an hour, got all the fluids full and hot and topped-off, shut it down, let it cool off for an hour, tightened all of the hoses intercooler included. Cranked it back up and drove it right away i feel a difference in throttle responce (also replaced I.P. this must be why). Smoke is terrible! Black smoke at low rpm, white smoke at high rpm!
Boost is fine at 15 psi so check timming again everything is ok.
so here i am, oil psi is good, temp is good idles good, responce is good, no leaks, no stinks, will hammer down in the morning see how everything improves.
(to be as clear as possible, power is the SAME as before engine failure at this point)

[jspringator]

I don't know that you will get any more power with the same boost on an 18 to one engine, but it should last a whole lot longer. You should be able to pump the boost up after break in shouldn't you? Emissions is probably the main reason GM went with the high compression engines in the first place.

[Bnave95]

Hammer down,get the rings seated. 18:1 will smoke more at first. once it has been ran in good,should be fine.Your Eng. makes for a great toe truck:)
Power will be a little less then 22:1 at lower RPM. Great build:cool:

[Patrick m.]

On your '98 block, which size outside main bolt holes did it have, large (like the 599 had) or smaller like the later 506's?

My '97 has the BIG outside bolt holes, just comparing...

Sounds great on the build!

Ran into the same thing on the cooler line size, mine was 1/2" NPT, so I just got screw in 1/2" NPT to 3/8" NPT adapters, works perfectly and doesn't stick out of the block more than 3/8" more than factory, putting this where a 6.2 was...

P.S. the lil T04B made the 6.2 run better!

J

just remembered..... outside main bolts WERE small. ( been very scattered the last few days please forgive)

[Patrick m.]

75 miles on the engine and smoke seems to be gone, except for the black smoke if i put it on the floor from a stand still.

This eng would be awesome if coupled with a standard trans, it makes great power from 2500 rpm up. It was like this before due to the larger turbo, but more so now.

Going to check on different turbine wheel, started to do this some time ago and got sidetracked by the GM-8, then again by massive engine failure.

My old I.P. must have been worn out, starts better, throttle is very touchy - very responsive. hitting bumps at slow speeds can cause throttle foot to bounce causing a big lurch forward, will have to get used to that and learn to avoid it.

The entire oil cooling system is now new, the 98 model system is much bigger for i would assume more flow. it appears to be more efficient than the one i took off which is a plus (this how i am justifying the extra cost of converting the whole thing).

more to come.

[Patrick m.]

Now i am playing with TDC offset.............................. I know this has been talked to death, but, from -1.85 to -.70 the only difference i can tell is noise!

In fact at -.70 the rattle is so much less, i hear more of the turbo than the engine.....keep in mind, i have a rather large Garrett, so at slow speeds and lite throttle my turbo is much quieter than the stockers.

I have yet to pull anything, and still just short full throttle bursts @ 130 miles on new engine!
I could admit i might have lost a tiny bit of low end, but i have already formed the opinion that this engine wont make power down low. Anyone who says it does is accepting lower standards.

When i say power down low, i mean blistering the tires at any rpm below 1800, rolling along at 5 mph etc. etc.etc.
Mine will roast the right tire turning right from a stand still,.... this doesn't count.
I had a 383 Chevy in an Impala (64) that would destroy tires at any rpm no matter how low, in first or second (350 turbo). now that's torque!

This engine will make very good power, from 2000 rpm and up. with out a GM series turbo.

I will play some more with TDC off set, but after more break-in time. I may have a haul to Chattanooga in the am, if so will prolly use my truck, gen-set is about 5500lbs, trailer is about 2100lbs.....should give good numbers over Mount Eagle mountain.

[john8662]

I could admit i might have lost a tiny bit of low end, but i have already formed the opinion that this engine wont make power down low. Anyone who says it does is accepting lower standards.

Ok, ok, been waiting to jump on you for this type of thinking on the 6.5L.

I do think that the 6.5 will make power down low, the problem with your 6.5 is the injection system, it's DS4. The DB2's produce fuel rapidly early on which helps the low end power thing.

The DS4's on the other hand are controlled to gradually increase the fuel output, depending on boost. I'm not sure about aftermarket chips, but I do feel that even they still have some of this timing setup. The main idea here is to reduce smoke on acceleration before the turbo can spool up and you have enough air to burn the fuel given.

My DB2 6.2 is always a little smokey out of take off, under a normal acceleration, not grandpa acceleration. I have often complained about this, the solution has always been to install an aneroid (sp?), to limit fuel at the beginning, until a given RPM.

The main idea to this tale is, I think it's your pump man!

Tire spin? My 6.2 with the Banks will light 'er up no problem, pointing straight no turn. If I powerstall, I get the tire (wish it was tires) breaking loose immediatly, then I start my burnout when I start seeing the good ol white smoke, it won't quit till I let off of it, i could burn a whole block if I wanted to...

J

[Patrick m.]

maybe i just expect too much. I am happy the over all power. This set-up actually provides power when it is needed, on the interstate at interstate speeds, the GM- series turbos will choke the engine at these speeds, at least this is my experience with them, both the GM-4 and 8 the 8 was better though.
So if the best power gains are going to be made from 2000rpm and up, this is how it will stay.