Well... I am building my ls vtec. But first, i need to check all the clearances... right?

Ok... according to BAMBAMs post "How to build a reliable ls-vtec/b20-vtec" the main bearing caps, must be torqued to 56 ft/lbs. And as i have ARP rod bolts... i must apply 26 ft/lbs according to the instructions that came with the bolts.

Now... i used a plasticgage to measure the clearances. The crankshaft diameter is .20=.50. My issue this time is that the plasticgage expands too much at only 56 ft/lbs of torque. But the rod bearing clearance looks perfect to me.

Well, here are the pics, so you can evaluate this measures and give me an advise.

This is the rod clearance.


Now... these are the main bearings clearance... i applied the same torque to 3 different main caps.




The crankshaft was micropolished, the bearings are ACL brand new. So, please tell me what you think.

Thx in advance.

 

Honestly they look fine to me except the last main bearing measurement. It looks like the crank was spun just slightly while taking the measurement. You should probably clean off the plastigauge and recheck.

Other than that, the mains look to be approximately 0.0018" clearance. What clearanc es are you shooting for?

The stock LS clearances are: 0.0009"-0.0017" for journals 1,2,4 and 5. 0.0012"-0.0019" for journal 3.

The rod bearing clearances look to be closer to GSR spec than LS spec, but that isn't necessarily a bad thing.

 

I agree for the most part with "snm95ls" but if you wanna be 100% sure and wanna make it perfect take it to a reputable machine shop and have them "line bore it to what ever spec clearance you want and throw some ACL's in that bia... Good Luck

 

i agree, rods look fine.

if you wanna tighten up your mains, you could always grab honda bearings for those. might be cheaper than having more machine work done.

what did they measure out to in inches? (you have the scale in mm in the pic)

 

Hi... thx for your comments so far. I will re-check all the clearances this night when i buy more batteries for the camera. MMMM.... and for killerpenguin21... the last picture shows the mm instead of inches.

Thx.

 

yeha i know i dont have plastigauge laying around right now so i was curious what that journal measured in inches, since thats what i always go by.

 

My uncle, who is a mechanix... said, that my clearances must be within the .002 range (the third square... the green one) because this is the tolerance for a crankshaft at .20=.50

I want to be close to:
.002 IN.
.051 MM.

And yes, i think i spun the crankshaft while i was removing the 3rd main cap, because its hard to remove them after they were torqued down.

As i stated before, i will re-check all the clearances this night. But for the rod bearings, i think 26 ft/lbs is perfect. I used to apply 35 ft/lbs to the stock rod bolts to the ls rods before, i dont know what i was thinking. But now i have a camera, i created a post... so you can guide me in the process of building this thing.

I will start building this engine next friday because i am waiting for a new gsr/type r oil pump. I want everything to be close to perfect while doing it myself.

Another question i have is... what oil do i need for the break in process?
In bambams post... he said we could use the cheapest we could find. I went to autozone yesterday, and i saw 1 qt x 1.50 dlls the brand is AUTOZONE obviously.
U think it is fine for the break in process??

i forgot to say that the oil is available in any spec. 10w-30... 20w-50 and on.

 

Use any standard 10W30, NOT synthetic, oil. You will be changing it often in the first few thousand miles, so there is not real advantage to spending a bunch of money on oil.

Just my $0.02 on th subject.

 

Find out the exact torque spec on the rods to measure the clearances with. Also, if using a torque wrench on the rods, use the shortest extension possible (or none if you can) -- a long extension will actually twist (like a torsion bar) giving you an inaccurate reading.

The torque spec they give for the rod bolts is usually way under the yield point of the bolt/stud. So its not going to hurt to torque a little higher--figuring most torque wrenches are pretty inaccurate anyway. Say 5-10 ft-lbs to be safe.

When torquing the mains and rods, make sure you use the lubricant that they tell you to use. I believe HOnda calls for plain engine oil for the mains and rods, and ARP tells you to use their own lubricant (if using ARP main studs and rod bolts). Using a different lubricant will require different torque specs.