It's really hard to tell from the pic but if you feel it is worn replace it it will never get any better and it's far easier to do now than later.
I have never used a gear drive and I hate the noisy ones.But why is it bad to use a good quality gear drive? Sorry to go off subject but maybe this will help him also.[email protected] said:But then watches don't have harmonic imbalance/iibration problems nor do they operate at 3500+ rpm.
A gear drive is the worst thing you can do to a small block chevy!!
The cam's distributor drive gear appears to show a deep amount of wear with a lip present about 2/3s the way down the tooth. If this really exists, the cam is shot. This could be the result of running incompatible materials between the distributor gear and that of the cam. In a competition engine the OEM type steel gear really wears heavily on the cam's cast gear. Although meant for roller cams, a bronze distributor gear transfers that wear onto the more easily replaced distributor gear.Biscuit6447 said:After many many months of adjusting and tuning, and lots of engine oil, i decided to tear my engine apart. The motor is a 327 large journal, 3970010 block, rebuilt in 2007, sat for 2 years, than given to me. It is basically a full race motor, but i didn't know that, so initial tuning was very difficult.
Turns out, 6 of the 8 piston rings' gaps were not 180* off. also, the first initial start up must have sent significant foreign material through the oil system because all the bearings have issues. They aren't spun or extremely worn, but definitely worse than what a 5000 mile motor should be like.
Also, i had horrible blow-by, so i used oil like crazy, fouled plugs a lot, and leaked a lot of oil.
So i am having the shop replace all that stuff, but my question is can i still use my cam after seeing what it looks like?
The distributor drive gear on the cam seams to have significant wear, but all the cam lobes a perfect and smooth.
The cam is a crane cams "saturday night special" cam. #111411 oval track mechanical flat tappet cam. 4200-7200 power band, 292/300 adv. dur, 256/264 @ .050, .545/.563 lift, 105 lsa. according to a chevelle forum i found this cam produces the best ET results in a 1/4 at the expense of idle quality and manifold vacuum.
I have all the lifters organized to go back in the same spots, but i want to know if the gear wear will cause timing issuse, and eventually fail.
As i was tearing the engine down, i noticed that there was excessive slack in the coyles double roller timing chain. (hope the video works)
So do i need a new cam, new lifters and a new timing set???
Why do they wear out quickly? If all the part are right, then shouldn't they last? I have had plenty of people say it will last 100k miles if it is taken care of.Engines such as you have just don't have long life spans, they're like rock stars, they shine brightly, but burn out quickly. Bogie
The operative word is take care of it. Wear is proportional to dynamic loads on the components. These type loads are proportional to RPM by the square so they get really big really fast as the revs go up. Excersions above 5500-6000 RPM start eating at engine life span very quckly. An engine built to race specs in terms of components and balance can last a very long time as long as you don't exercise the top end too often.Biscuit6447 said:Good info, thanks.
I guess i also should have said that when it was rebuilt, it was broken in and then used for a few 1/4 miles passes and 100 miles of street time. THEN it sat for 2 years. So it was already broken in, but i did prime the oil system before i ran it for the first time.
Why do they wear out quickly? If all the part are right, then shouldn't they last? I have had plenty of people say it will last 100k miles if it is taken care of.
I had a mild built 350 once with a gear drive, and i hated it. Also, that motor had 6 spun rod bearing when i tore it apart.
As for my plan with this motor: I plan to use it as a Seasonal driver from may to september (live in Colorado) And during that time, use it as a "weekend warrior" and have it as my fun car. I have no problem putting a lot of time into the engine and maintenance.
Just about everything attached to the motor is aftermarket. The distributor is a procomp, i put in a much better fuel system, all the luxuries have been removed, and i don't ever let the motor go above 190*.
Can anyone suggest a good thrust button? I have need seen or used one, so i don't know which one are the good quality ones.
There you are with piles of stuff and a long holiday with no plans. Next thing you know the Alfa has a small block Ford in it, the Monza ends up with a small block Ford bolted to its Saginaw 4 speed, the GMC S15 parts truck ends up with a Franken Mouse Chevy, the Beechcraft gets an Oldsmobile, the Ford Courier gets a 289 and a top loader, the V-Max gets converted to chain drive, the old Ford pick up with a 292 gets Lincoln 430, the 49 Chrysler woody wagon gets a 440, the Toyota Hilux pick up gets a Olds Toronado dumped in the bed, the old lady's Jag gets a 350, etc. Just can't sit still and piles of odd stuff get my attention, pretty soon the thought, "I wonder if I can do that" gets in my head. Sooo, I crank up the coffee pot turn on KZOK (the kick-*** station) and get to messing around. I love KZOK, back somewhere in the early 1990s Boeing had landed there billionth airplane order in a week. I was out in the shop with the rain pounding on the roof, like that's news around here. Now some genius in city hall back in the 1970s decided that Seattle needed a nick name, so in keeping with everything covered in moss and blackberry vines they decided on the "Emerald City". How original! So the DJ breaks in on the Stones for the news and announces the Big B has more orders than there is aluminum to build 'em, everybody will have to turn in their empties at the recycle center. He concludes this news piece with "Emerald City my ***,,, This is Jet City". For sure dude!DoubleVision said:Bogie, you gotta be kiddin. You mean you took the time to reweld a set of LT4 heads? If the gain was a 100 horses I might consider it but not for less.
Gear teeth should be smooth. Just replace the pump.Biscuit6447 said:Is it possible to find a cam with spring requirements very close to what i already have?? I have found a few cams i like, but i need to know if i need to buy just the cam, or the kit that includes the cam, lifters, springs, and retainers. The cams i am looking at are all isky cams.
I just remembered.... since i had something go through my oil system, i decided to look inside my oil pump. Are the gears supposed to be smooth? Because they seamed to be all scuffed up, and one of the gears has a significant size dent or chip in one of the teeth. It is a high volume pump with taller gears.
can you but replacement gears for the oil pump?? or do you need to replace the whole pump?
Would my 327 be suitable for 7500 rpm? It is a large journal 327 forged crank, arp main studs, forged i-beam rods, arp rod suds (press in with a nut) and forged pistons.
The pump combined w/heavy oil could account for some of the chain stretch and dist. gear wear you are seeing.Biscuit6447 said:It is a high volume pump