"White Knight"

Let's say I want to put in a cam like the LE3 cam. What should be done to run this up to 6500 rpm. I would guess you'd have to replace all the bearings, but what ese would you need to do? I assume trying 6500rpm with the worn bearings would result in a spun bearing correct? I am not sure you'd need a Hydra-Rev kit at 6500, but then again i don't know. Or i guess just run stiffer spring rate. SO what all do you need to spin her safely to 6500-6600rpm?

"White Knight"

I ment LE2 cam

turbo_Z

If you are going cheap then yes, replace all the bearings and add a high pressure oil pump. Otherwise just rebuild the motor. Around here I can get a rebuilt LT1 shortblock for $800 + core charge.

FRMUL8D

I'd sure like to know where 'here' is. That's not a bad price. Is that all stock components just freshened up with new bearings, etc.?

Spinner

Summit's lt1 rebuild kit is ~$580 with .030 forged pistons, new rings, bearings, etc. Figure on that + ~$300 in block work, plus labor if you dont have the tools to set up the bearings, and your good to go

Loading

With the pistons .030 bored over, are you going to see any increase in power?

5.0THIS

If it's not making power up there, there's no need to spin it that high. If your car has stock heads your power may be lower than 6500

turbo_Z

Yep that basically all you get.

Heatmaker

Honestly... by building a bottom end that's ready to go there......

93turbo5oh

i dont understand why everybody is having trouble with spinning bearings on motors that have higher mileage but are taken care of. we've spun stock LT1 shortblocks 7000 without problems. the looser bearing clearences should make it harder to spin a bearing unless its low on oil/oil pres, or during the heads/cam swap coolant got in the oil and the oiling system wasnt flushed before startup. i think another possible problem is everyone trying to spin them over 6000rpm with these thin 0w-5w oils.

"White Knight"

What oil weight do you recomend?


by the way it is with the matching heads......because like you said spinning it that high on stock heads....get's you nowhere.



I am thinking maybe i'll take the gamble and just do it when summer gets here. If she spins a bearing which i pray it doesn't......i'll just sit that season out and try to get another motor together.

"White Knight"

I wonder if I went with the summit forged kit if i should go ahead and get 4 bolt mains and new rods. How much extra is maching for 4 bolt mains on these LT1's?? Cause then i'd feel safer spraying a small 100shot on top of the head and cam.

93turbo5oh

they were heads/cam combos but to the shortblock it doesnt matter, its just rpm and load. and as far as oil. id run a 10w30 when i was gonna run it hard, at minumum. the bearing clearences grow as the mileage piles on. i run a 10w30 in the winter (texas) and a 20w50 in the summer. if you live up north i can see running a 5 or 0 weight in the winter, but dont rev it when youve got those oils in it. we use 20w-50 castrol gtx in our 1300cc race bike engines. the whole thing about the lower weights flowing better when cold is offset by the fact that the thicker oils stay on the bearings. i havent even changed my LT1 over to 10-30 for the winter yet. i may not since its not my driver and i dont have to start it cold. i dont rev mine over 6000rpm unless i have 20w50 in it.

ejfagala

The bottom end has little or nothing to do with it. Higher RPMs usaly cause problems because of valve train not spinning bearings You build a valve traing that can handle the RPMs to answer your question. Better springs lifters Roller Rockers, well you get the idea. BTW why, unless your cam is still making power you are spinning the motor just to spin it

Heatmaker

That's new.... guess I'll save myselft 4g's on this engine build up...

on another note...

Could of sworn high RPM's and stock internals don't mix....

Build a bottom end that can handle the load... and a top end that can take you there.