1. So I purchased the 400 kit from t meyer with his special pistons from I believe KB? They suggest a larger top ring gap and a second of .004 per inch of bore.......I assume a standard 351m block bore is 4.000? mine was bored .040 and KB suggests using a top gap factor for street applications of .0065 so if I go by the above, that put me at .026 on the top and .016 on the bottom, what are you guys doing for the gaps?

2. I also ordered a new balancer from tmeyer and had my rotating assembly balanced with it.....however I found this on the web:

The 351M uses a different harmonic balancer than the 400 -- It is best to buy a new 400 harmonic balancer to go along with a 400 crankshaft. You can use a 351M balancer, however, you will have to rebalance the 400 crankshaft by adjusting the counter weights to bring the assembly into balance. Also, the timing marks on the 351M balancer will be nearly useless on a 400 crank -- I know because the engine shop used the 351M balancer on my engine. I had to set my timing at 20+ degrees to get the engine properly timed.

from what I read they are all balanced the same which disproved the above statement, I will be locating tdc on my motor....Any thoughts on the above statement??

3. Also, is it okay to reuse my main cap bolts?, they look okay

 

1. Go with the manufacturer's advice...The bores are slightly tapered and a little oblong - out of round. What do they say about the oil rings?...they're on the bottom.....Don't forget to install in the correct orientation (dots for each ring) and smooth out your filing marks with some #180 grit sandpaper. Yes, the 351M/400 bore (stock) is 4.000", with a 4.00" stroke on the 400 and a 3.50" stroke on the 351M.

2. Yes, actually there are three kinds of harmonic dampener --the 400 manual trans is thicker/heavier than the 351M manual trans, and the timing degrees are different - !0 or so degrees if I remember. Then, the 400 auto balancer is a different turkey than the other two....falling somewhere in the middle - thicker than the 351M but thinner than the 400 manual.

Mind you, these are all from a 4 wheel drive vehicle, if it makes any difference. The numbers on these guys will make you scratch your head, 'cause they're the same. Why? Ask the ferd dudes.

I did have pictures of the three balancers stacked one on top of each other, to show the differences, but ya think I can find them now? Haha. I could scrounge around and try and find the numbers/weights, etc of the three if you want...they're here in my desk somewhere. ANd, they are all the same diameter...6.50" I believe.

3. Surely, re-use the cap bolts unless it's obvious the some are longer than the others. They can only take so much tensile torque before they're history - how many times have they been used/re-used?

 

this is the first time they have been reused = first rebuild ever

 

Ok....your cap, rod and head bolts should be good.

Good luck

 

Bottom to top:
400 stick shift 4wd
400 auto trans 4wd
351M stick shift, 4wd

Found some pictures....harmonic dampener

 

i BOUGHT A REPLACEMNT FROM T-MEYER.......so think I'll be fine?

 

Tim knows his way around these engines.....I'd trust him to give you the right stuff.

You could always ask him.....express your concerns.......nice guy, and won't jump on yer **** for asking....show him the pictures...

 

yeah, I'll call him most likely...........hey, how far down in the bore do you stuff the rings to measure for gap? I have a tool I made to square them up and it sets them down about 3/4 to 1 inch

 

You have a 4.0" stroke....set one of the pistons squarely in the cylinder and check the depth of travel.....I think you should be ok with the manufacturer's instructions... they should have taken all that in consideration when giving you the numbers...along with the ring heat expansion and offset. When you call Tim, ask him to verify those numbers also. You should be good with the given numbers.

 

I might have had a brain fart when answering your question about where to measure the ring end gap....Use the piston or your tool and check the end gap about 1.50" (maybe less) from the bottom of the bore. You do have some good feeler gauges, no?

Sorrry...I'm a grumpy old fart and get confused/sidetracked easily...Hehehe

 

yes I have all the necessary tools......plenty of feeler gauges

 

Cool beans, man. Sometimes I get too much blood in my alcohol system........

 

lol...............

 

okay I have done quite some reading online regarding this and from experience on my last rebuild ten years ago running an overbore of .040 the ring gaps were about .040 on the top actually just a tad over that and the second ring ring was also a .040 thou gap.

after ten years and very low mileage like a couple thousand miles on it with a very rich running edelbrock produced a fair even amount of carbon build up and seems like at that gap it was allowing the right gap to have enough gas and pressure excape down the top ring gap which was good for a rich running hi po motor 9.5CR

This last last rebuild I did went a smaller gap in those ranges you are talking about .022 top and .018 second is what I went with in hopes that going back to stock fuel system that I recalibrated and tunned out really lean before the tear down so I could use it to break in the new valve train.

It really livens up the top end leaning it out but It does feel on the ragged edge where if I hang on it to long at WOT I get nervous but I went smaller on this one due to different oil that I will be using with more detergents to combat the carbon build up in the chamber so instead of using a lager gap like i did last time for the purpose of allowin fuel vapor to escape through the big top and bottom ring so that the vapor doesnt build up in the carbon and detonate. that worked flawless for me the last ten years on the engine.

this time I will rely on the better oil detergents to break the vapor down to stop detonation along with standard good tuning and ignition maintenance and upgrades over factory. so just more of a pure performance builders stand point this time I wanted as much pressure as I could get since that will = more efficiency in the combustion process.