Engine Assembly

[SLED]

I was going to respond to Abe & Dale's query in the Wasteland section but figured it was worthy of its own thread.

SorryI couldn't elaborate further last night (my 20th anniversary) but there are critical things that get overlooked by many assemblers once they get their bits back from engine reconditioners.

Quotes from the Wasteland thread:

Machining is almost finished. The R.E.V Rods only had standard ARP boltsinstalled, but had ARP2000 bolts loose in the box. So they installed theARP2000 bolts and checked the bigend's, due to the extra clamp loading therewas some variation and distortion, so they had to be honed again. This may havebeen avoided if I had gone with Eagle rods, as they come manufactured withARP2000 bolts.

Isn't that idea behind torque plate honing or line boring after using upgradedstuds, as the increased torque to get the correct stud stretch distorts thebolting surfaces. They are saying that the increased torque between the baseARP and the ARP2000 rod bolts (which is around 10ft/lbs from memory) distortedthe big end, which i would think it would.

torque plate boring should be performed even if using the standard head studsDale

Barrelling effect from boring is different cause you're removing metal from abore then clamping it down whereas rods are pre-torqued before they are linebored from factory

Maybe the extra 10 or so lbs does have an effect (not sure) but you then haveto consider brg crush and tang depths as well once you start removing metalfrom big ends

Would've been better to get an aftermarket rod rather than stuff around withstandard rods and trying to make them do what they're not designed to do methinks

I've always been a little concerned about the mixing and matching of conrods and bolts....fine if it's purely for strength but I get nervous once the torque specs get altered (usually increased).

Dale you're probably already aware of the critical nature of brg crush so this is for the rest of you.

Brg halves when placed together, do not make a perfect circle, they're slightly elliptical so they can conform to a perfect circle when manufacturers torque specs are applied.

Try this....get a brg shell and position it evenly in a conrod cap then place a straight edge across the cap and hold it up to light.......brg protrudes past the conrod mating surfaces (well it should!!)

When I hear that a conrod sizing was fine until new bolts were applied and now locks up because of increased torque settings, it's usually a case of excessive brg crush.....we used to call it "side pinching" which is a common term in engine reconditioning.

In effect, the brg (whilst torqued) is no longer round due to increased torque but instead has had its sides, where the 2 halves mate, bulge inwards. This can cause lock up due to metal on metal contact. Brgs should always be cushioned from the crank pin by a film of oil....never touching.

Tangs are designed for brg location during installation and Crush is designed to stop the brg from turning inside the rod......I bet most people thought that the Tang is the only thing that stops the brg from turning......wrong.

Now all due respect to other engine reconditioners out there cause alot of them have been in the game for as long as I have (or longer) but honing of new conrods and main tunnels worries me. We would either machine a rod or main tunnel with a tool on a line borer to manufacturer's spec or not touch it at all. Honing removes only a slight amount of material but it does it indiscriminately and by honing alone, all you're doing is minimizing brg crush to aleviate a different problem which can in turn open a new can of worms.

If I'm missing something here, I'm def open for correction by the gurus out there.

Getting back to Abe's build.....thru much trial and error at A.I.R. years ago, I always found that the best bolt for any given rod is the rod it was designed for.....hence why I hate monster bolts in standard or average aftermarket rods.

[mid life crisis]

i went into sprints the other day looking for some plasti gauge the guy looked at me like i was from mars even after i explained what it was and what it was used for he still was confused .....just shook my head and walked out ended up getting some from ebay lol

[SLED]

Haha, yeah no surprises there Deano

Repco & SouthCotts is where our customers used to buy the stuff back in the day..........we eventually started selling the stuff in a few different thicknesses as well cause most customers couldn't afford a range of different inside and outside mics

[mid life crisis]

i have a few different sets now i was bought up using plastigauge and old habits die hard i have a nice alloy headed 347 windsor with alloy rods and forged pistons comming in for a freshen up as soon as i get the all clear from the doc "recovering from hernia op atm" still a few of us old school builders out there lol.

[Bl4cK32]

i went into sprints the other day looking for some plasti gauge the guy looked at me like i was from mars even after i explained what it was and what it was used for he still was confused .....just shook my head and walked out ended up getting some from ebay lol

auto part shop monkeys are a joke. They hire sales people, not spare parts experts. I tried to get a rocker cover gasket for a magna, and ended up leaving after trying to explain to the guy the difference between a rocker cover gasket and a head gasket...

[D_Stirls]

Here's some more reading for Y'all;

bearing tech info.pdf

[SLED]

Good article Dale....even shows the use of Deano's plasti-gage in there.......Clevite and one other company (can't remember their name) actually supplied the stuff in their brg packets.

They touched briefly on bi-metal brgs but didn't go into detail about tolerances between such a brg (ie. copper/leads) vs something like an alu-tin.........climate and thickness of oil can also predetermine the final clearance as well, but we're only talking .00025" - .0005" (1/4 to 1/2 thou) at best

[mid life crisis]

Good article Dale....even shows the use of Deano's plasti-gage in there.......Clevite and one other company (can't remember their name) actually supplied the stuff in their brg packets.

They touched briefly on bi-metal brgs but didn't go into detail about tolerances between such a brg (ie. copper/leads) vs something like an alu-tin.........climate and thickness of oil can also predetermine the final clearance as well, but we're only talking .00025" - .0005" (1/4 to 1/2 thou) at best

here are a couple of pics of a 308 im doing at the moment for my dirt circuit car

this valley area has taking me days on the die grinder and flapper wheels

308+40 tho flat tops. balanced crank rods and pistons. block decked arp rod bolts and head studs hv oil pump brock baffled sump and lots of little tricks that i keep to myself lol

[D_Stirls]

and some more;

http://www.precisionenginetech.com/tech-explained/2009/06/01/race-bearing-tech-part-1/