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Discussion Starter · #1 ·
So i recently inherited this 350 tuned right and running properly. its a 3970010 block, 2 bolt. When i pulled the heads to have them beefed up, all the cylinders had a nice crosshatch pattern. My question is: How long do rebuilt 350's last??? This is my daily driver 1988 camaro and here are the specs;

.030 over block
462 heads, pocket ported, 2.02/1.60 stainless steel valves.
Crane cams 111411 solid flat tappet cam 292/300 adv. dur, .545"/.563" lift
1.5 billet roller rockers, dual valve springs, push rod guides
dome top pistons, ARP studs, double roller timing chain,
Weiand 7546 X-celerator single plane intake, edelbrock 750
Crank and alternator underdrive pulley's
4.10 posi rear, stock tranny and driveshaft.

some random forum said that rebuilt motors need bored out again after 10,000 miles or less. is this TRUE????

ALSO, I really need to switch from my stock t-5. I would really prefer the TKO-500. What else do i need to change to the TKO??? I would like to drag race at least once, what kind of bellhousing and other drivetrain hardware do i need to be safe at 7200 rpm??? Any ideas of what a 1/4 mile ET might be???
 

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boatbob2
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chev 350 life span.....

Hi,if you change oil to synthetic,dont overheat it,and dont beat it to death,this engine will go at least 200,000 miles.i have one in my firebird with 262,000 on it. never been apart. :) :)
 

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tuning is VERY VERY VERY important for longevity, so is using good gas and oil. I would only use Mobil 1 or Valvoline oil, with a ZDDP additive added at EVERY oil change and AC Delco or Wix oil filters. That along with a good tune and your engine will last well over 100,000 miles, thoguh tthe valvesprings may fatigue before that. Good oil, good tune- VERY IMPORTANT.
 

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Use a high efficiency filter if you are using synthetic oil. Two of the top rated high efficiency synthetic media filters are Mobil 1 and Purolator Pure 1. The Pure 1 filter is just as good as the Mobil 1 filter and is half the price. I used to use nothing but Mobil 1 filters on my vehicles until Mobil raised the price on them, then I switched to Pure 1 once I did a little research.

Vince
 

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Biscuit6447 said:
Ive heard that mechanical flat tappet valvetrain wear out a lot faster.
A mechanical flat tappet cam and lifter arrangement will have approximately the same life as a hydraulic flat cam and lifter arrangement if all the supporting elements are matched to the cam according to the cam grinder's recommendations and instructions and the two motors are operated in roughly the same rpm range.

A builder would normally spec a solid cam where the rpm's would be extended, so maybe that's where this heresay came from. Yes, if the solid cam is operated at higher rpm's, over what you would do with a hydraulic arrangement, then everything is going to take a worse beating and wear out faster.

Hydraulic lifters will pump up and float the valves, limiting rpm's, whereas a solid lifter cam will rev to whatever the limit of the remainder of the valvetrain (spring pressure, valve weight, etc.) and reciprocating assembly is (weight of the crank, rods, pistons and the material they're made from).
 

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A big factor for a solid flat tappet cam life is valve lash- you want to keep it on the tight side of the spec for an iron block/iron head sbc. Tuning is SO very critical to engine life and I cannot stress that enough. As far as the filter goes Mobil 1 may make a decent filter- I've never used them and I probably never will, Wix is the filter IMO but they are sometimes hard to find.

FWIW Rotella T is no longer the oil it once was. If you're going for an off the shelf oil Mobil 1 and Valvoline synthetic are the best but Valvoline conventional is a decently close second IMO.

For the ZDDP additive you can order it from competition products and if you get 3 or more bottles you get a discount. The way I drive and the number of cars I own I go through about 6 bottles a year. So it saves me a few bucks to buy in bulk and its handy to have it on the shelf- I also buy oil in bulk when there's a sale and the same for filters.

If you're REALLY particular you can also save and catalog your used filters and spark plugs to monitor the tune, which I did for a while, but its really not needed as long as you analyze them closely when you change them.

Again- TUNE, OIL, and GAS are CRITICAL to engine life.
 

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ap72 said:
A big factor for a solid flat tappet cam life is valve lash- you want to keep it on the tight side of the spec for an iron block/iron head sbc.
Any solid cam you buy will come with the manufacturer's recommended valve lash figures. They know the characteristics of the grind better than anyone and while you may rock the lash around those points a few thousandths either way to alter the characteristics of the power band, going very far either way would be to invite failure of components.
 

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techinspector1 said:
Any solid cam you buy will come with the manufacturer's recommended valve lash figures. They know the characteristics of the grind better than anyone and while you may rock the lash around those points a few thousandths either way to alter the characteristics of the power band, going very far either way would be to invite failure of components.

yes but too loose of a lash wears out valves and lifters faster, too tight can lead to a burnt valve. I'm not trying to be contradictory just giving the reasons that you need to watch that for longevity.
 

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I was a Chevy mechanic in 1973 and I remember explicitly a blue 69 Z/28 Camaro that came in every so often for a valve adjustment. Myself and my buddy were the only two the owner let work on his Camaro and he watched us the whole time. Back then Chevy had a 5yr/50K mile warranty and if I remember right that valve adjustment was under factory warranty.

Vince
 

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Discussion Starter · #12 ·
Thanks for the input. I do have another question; is it natural for a little smoke to come out of the exhaust at high rpm's??? I have no cats, and a decently high compression (dome to pistons). But not like blue oil smoke or way way to rich type smoke but enough to see at night in someone's headlights.

I was just browsing through some forums, and running pump gas on high compression motor is limited, but i have not detonation or pinging. As you get to those high rpm's, the pressure increases and causes the pump gas to not burn right????
 

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Discussion Starter · #13 ·
better than a new thread

I've already been over my attempt at pump gas on this motor, but based on my valve overlap i have low vacuum at idle and all the way up to 2000rpm. Does this mean that i am just getting away with pump gas at low rpm, and the high rpm causes smoke for some other weird reason???

This just came to mind, an i would really like to know so that i don't kill my engine in the next week. :spank:

thank, josh :welcome:
 

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Discussion Starter · #14 ·
Thanks F-BIRD'88, i know you have posted many replies to many of my posts, but i want this to run right. Other than the high CR, everything isn't stock. procomp distributor re-curved to limit mechanical and vacuum advance, mallory 140 series fuel pump w/ 1/2 aluminum hardline and all stainless braided -an fittings. exhaust, intake, gears, etc.

I have been checking my plugs all the time, and no signs of detonation. I have had my heads off twice and the cylinder walls still have a nice crosshatch pattern. the pistons really aren't that black. As for blowby; when i remove the pcv valve as the engine is running, what is a lot vs a little blowby??? Is normal blowby easily seen???

Where could i find picture that illustrates a quickly worn out cylinder wall due to the problem i MIGHT have???

Just this week i solved my pcv oil sucking problem by changing the valve covers. The baffles on the old ones just were not working right even though they were there.

Now i have another question: Since there WAS oil on the plugs and now that no more oil is entering the combustion chamber, is a light ash deposit normal??? NOT once have i had a missfire or a case of hard starting, the plugs seam to fire every time no matter the rpm or temp.

Thanks for the input.. again! :welcome:

I will post some pics of my plugs right after this
 
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