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LT1 crate

3K views 16 replies 4 participants last post by  Karl Nancy Koenig 
#1 ·
So the used '94 Roadmaster engine I swapped into the El Camino ten years ago started to make expensive noises just before Christmas, and my present to the car was a BluePrint crate replacement from Summit. (actually just got it yesterday) Blueprint calls it a 94-95 Corvette engine, I can see that the aluminum heads will save weight over the original iron heads. Now in the process of stripping accessories off the old engine to install onto the new.
This forum has been helpful as I lurk. Anything unusual about building up this engine I should know?
Already noted how the previous assembly used sealant on the intake manifold bolts to keep the oil inside, and center punch dimples on the mating surfaces of intake manifold and block to hold sealant there.
I assume I can pull the damper and flexplate off the old engine and install onto the new one.

Will let you know how things go, and I's sure there will be questions as I get into the project.
 
#3 ·
, and center punch dimples on the mating surfaces of intake manifold and block to hold sealant there.
.
while some have done this to the front & rear of block & manifold....rarely needed. I have always had perfect results using Permatex Black "ultra" RTV

I prefer the felPro "printle" manifold gaskets

Get a ARP solid metal oil pump drive shaft

be VERY careful on TQ of the smal bolt that holds on the oil pump drive gear. Use loc tite and just hand "snug" on it. The plastic top is old and can easily crack so be careful on TQ
 
#4 ·
Thanks for the advice. The oil pump drive shaft is common to SBC, right? There was a new oil pump in the crate with the engine, but not a shaft.
I expected to re-use the water pump drive shaft, is that OK?
And the first lesson learned is that the BluePrint crate engine comes with a gasket set. Did not expect that, so I'll return the gaskets I bought separately from Summit. Except for the exhaust gaskets -- got a pair the Summit tech recommended for use with headers.
 
#12 ·
Next question is on torque, since my old engine had iron heads, and all my torque specs are for iron heads. New engine has aluminum heads.
Torque for spark plugs 11 lb-ft -- seems awfully low. Is that also the correct torque for aluminum heads?
Do head bolts need re-torque after the first heat cycle? Is the torque different from Iron heads?
Same questions for intake and exhaust manifolds...

Thanks again for the help
 
#13 · (Edited)
Because aluminum has a different expansion & contraction rate than cast iron, aluminum heads need to have bolts retorqued more often than iron heads on an iron block.

But not after the 1st heat cycle. My torque schedule on iron block with aluminum head engines is after the first 500 miles. Then after it reaches 1000 miles. After that, torque heads every 12,000 miles. This may seem excessive to most people. But I kept Italian cars, known for blowing head gaskets frequently, on the road and trouble free in that area.

Don't have the spark plug torque for aluminum heads handy. But if iron heads get 11 ft lbs, then aluminum heads will be less torque.

Service manual will have all the specs. We have 93, 94, 95 & 96 at www.mediafire.com/?40mfgeoe4ctti

I also forget if 96 or 97 lt1 engines use torque to yeald bolts. These bolts are not supposed to be torqued more than once. If you have these type of bolts you would need to replace head bolts every time you torque. Factory service manual will say if you have these type of head bolts.
 
#14 ·
Thanks all for the advice. Engine itself is together -- manifold to oil pan. Got the accessory brackets on, then spent half a day messing with spark plug wires to keep them out of trouble. They're going over the top of the headers instead of underneath this time. One old wire was burnt despite header wrap and boots on the plug leads.
Yes the old timing cover fit the new block, no problem. Took a couple tries to get the opti lined up and seated properly.
Now to lay in the wiring harness and support it to keep it out of trouble.
 
#15 ·
Wiring is in place, but the latest adventure is flex plate bolts. Factory must have used super locktite--plus 20 yr corrosion--could only break one of the flex plate bolts loose. Others just rounded off. Fortunately my favorite vendor of pre-tested parts had a flex plate on hand so we'll get the show on the road. Mate it to the trans and it will start to look serious. :)
 
#17 ·
And it's running, but...
- 3 injectors aren't firing. Had injectors cleaned and flow checked during the swap, so we're checking the wiring.
- Oil leak at the front. Trying to see if it's the intake manifold or timing cover.
- Coolant leak where an elbow screws into the water pump. screwed those elbows in as tight as I dared the first time, with a little RTV for good measure. But it looks like I might have been a little too gentle (not my usual problem)

And of course the headers need to be retorqued.

Feels like 3rd down and goal to go on the 2 yard line. :)
 
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