help - i screwed up on my v8 - advice needed |
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help - i screwed up on my v8 - advice needed |
Scott S |
Feb 11 2016, 01:56 PM
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#41
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Small Member Group: Members Posts: 1,697 Joined: 30-April 03 From: Colorado Member No.: 633 |
I did this exact same thing 25 years ago (too long of a bolt on the intake) with exactly the same end result. It was on a fresh rebuild and the push rod broke within 10 minutes. I replaced all of the pushrods, got the right bolt, and the motor went 180k without any issues before the van it was in was sold - and we beat the crap out of it. I don't think we even changed the oil after the initial damage happened.
Obviously you need to look for any additional damage, but based on my situation, that motor is far from toast unless you see other damage. Good Luck! (IMG:style_emoticons/default/beerchug.gif) |
69telecaster |
Feb 11 2016, 02:26 PM
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#42
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Member Group: Members Posts: 101 Joined: 4-April 10 From: White Cloud, MI Member No.: 11,558 Region Association: None |
I have a fresh '76 400 with increased compression and a Voodoo cam, but that's kind of a truck motor. I'm working on a '66 327, and there's a '65 283 waiting.
Just in case. |
jimkelly |
Feb 11 2016, 03:07 PM
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#43
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
what i'd really like is a low power/high rev sbc to better match a stock 914 trans that does not have a flipped H 5th gear. at 70mph my engine is spinning at about 3,000rpm. 75mph is about 3200-3300, which I do not mind. but I think a typical sbc needs to be shifted at 4000 to be some what gentle on it, 5000 is pushing it and 6000 is asking for trouble I think. maybe I just need a rev limiter set at 4500. oh, and ideally, it would sip gas too (IMG:style_emoticons/default/smile.gif)
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veekry9 |
Feb 12 2016, 10:32 AM
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#44
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OldMember Group: Retired Members Posts: 3,068 Joined: 17-June 13 From: TO Member No.: 16,025 Region Association: Canada |
https://www.youtube.com/watch?v=OsGqmOQus6Y How to. (WYIT) A dab of axle grease will stick the keepers to the valve on reassembly. Use a magnet to pull them out. Do TDC for each cylinder,because it's easy and keeps murphy outasite. / |
Andyrew |
Feb 12 2016, 10:51 AM
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#45
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Spooling.... Please wait Group: Members Posts: 13,376 Joined: 20-January 03 From: Riverbank, Ca Member No.: 172 Region Association: Northern California |
what i'd really like is a low power/high rev sbc to better match a stock 914 trans that does not have a flipped H 5th gear. at 70mph my engine is spinning at about 3,000rpm. 75mph is about 3200-3300, which I do not mind. but I think a typical sbc needs to be shifted at 4000 to be some what gentle on it, 5000 is pushing it and 6000 is asking for trouble I think. maybe I just need a rev limiter set at 4500. oh, and ideally, it would sip gas too (IMG:style_emoticons/default/smile.gif) LS1 with an Audi trans is a pretty darn nice swap.... Many members have done this. |
whitetwinturbo |
Feb 12 2016, 11:33 AM
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#46
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Honey, does this wing make my ass look fat? Group: Members Posts: 1,391 Joined: 22-October 11 From: Newport Beach/Kalefornya/USA Member No.: 13,704 Region Association: Southern California |
283 Chevy will rev (IMG:style_emoticons/default/beer.gif)
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zipedadoo |
Feb 12 2016, 11:54 AM
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#47
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Member Group: Members Posts: 135 Joined: 23-January 14 From: Arizona Member No.: 16,921 Region Association: None |
What about a 4.3 V6? Everything bolts up just like the 350. Same engine, just 2 cylinders missing.
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mgp4591 |
Feb 12 2016, 01:14 PM
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#48
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914 Guru Group: Members Posts: 5,363 Joined: 1-August 12 From: Salt Lake City Ut Member No.: 14,748 Region Association: Intermountain Region |
What about a 4.3 V6? Everything bolts up just like the 350. Same engine, just 2 cylinders missing. More of a torque motor but still a good one. For the good power and high revs, go with the 327 block and the 283 crank... viola, the 302! (IMG:style_emoticons/default/aktion035.gif) |
Justinp71 |
Feb 12 2016, 02:40 PM
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#49
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Senior Member Group: Members Posts: 1,582 Joined: 11-October 04 From: Sacramento, CA Member No.: 2,922 Region Association: None |
I used to have a built 350, revved to 6500 all the time, no problems. Its all about the valve terrain. Need good valve springs so the valves don't float. A stock motor should be good for atleast 5500, I'd recommend looking up your particular engine if you can. With a 914 I'd mostly be concerned with going around corners and not getting oil, its not a dry sump like a six is. The oil has to be scavenged on the bottom of the motor. Probably only a real concern with a track car, that will see higher g forces. But make sure your oil is always full. |
jimkelly |
Feb 12 2016, 05:27 PM
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#50
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
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jimkelly |
Feb 12 2016, 05:28 PM
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#51
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
when people say a sbc can be reved to 6500 or some other number, do they mean it can be run for 15-30 mins at that rpm or do they mean that it can be screamed to that number and then promptly shifted??
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mgp4591 |
Feb 12 2016, 05:54 PM
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#52
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914 Guru Group: Members Posts: 5,363 Joined: 1-August 12 From: Salt Lake City Ut Member No.: 14,748 Region Association: Intermountain Region |
when people say a sbc can be reved to 6500 or some other number, do they mean it can be run for 15-30 mins at that rpm or do they mean that it can be screamed to that number and then promptly shifted?? Depends on how you build it. Get a Traco engine and it'll run all day at 7grand. Another friend had a 25k Rehrer-Morrison smallblock that'd rev to 14g but not for too long. Big bucks go a long way in building a revvy Chev engine but you probably don't need that. I've seen some impressive numbers and rev ability from the 4.3 v-6 too - look some of them up and see if it's what you want. They even sound kinda cool! (IMG:style_emoticons/default/shades.gif) |
veekry9 |
Feb 12 2016, 06:26 PM
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#53
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OldMember Group: Retired Members Posts: 3,068 Joined: 17-June 13 From: TO Member No.: 16,025 Region Association: Canada |
https://www.youtube.com/watch?v=gGT_qP14Hig https://www.youtube.com/watch?v=RkJ3fd9_k5g (IMG:style_emoticons/default/happy11.gif) http://www.bobistheoilguy.com/whatisoilanalysis.htm https://en.wikipedia.org/wiki/Chevrolet_small-block_engine http://www.permatex.com/products/product-categories http://www.chevydiy.com/chevy-small-block-...nd-valvetrains/ Large stationary gensets and power transmission lube systems are analyzed regularly on a schedule as a preventive measure. The oil,when warmed,will flow through a fine filter cloth which will capture various large metallic particles. The microscopic ones will pass through,mostly.The large chunks are in the bottom of the pan. Mustn't leave those there,to be picked up and pumped by the fresh oil. While the pan is dropped for cleaning,have a look at the bottoms of each bore for signs of scoring. Peek into the cylinder at BDC with your borescope so a picture of all 8 bores are a known condition. Inspect the cam's lobes,from the valley top,keeping the order of the lifters and pushrods maintained(wear pattern matching). A dissasembly and cleaning of the pushrods and lifters is a detail sometimes left out. While the tallblock is half naked,a thorough solvent wash to clean the sludge off will allow the fresh oil to be fresh. A big question at this point is the condition of the cam chain,have a look up and search for slack. Roll the crank slightly to observe,and if it's acceptable you won't have to drop the drivetrain. Detail oriented motivation would have several main and rod plastigage clearances checked at this point,along with the oil pump's. The results of the top end leakdown tests will tell the wear condition of the valves and rings. Marginal upstairs means the same below,it is now the time to decide if a new set of bottom bearings should be installed in situ. If so,plastigage each one,being very careful not to shave any of the shells,nick any journals,working in a spotless method,super cleanly. Use brake cleaner spray to wash the parts,assembly lube on the shells.Measure(mike with correct anvils) every one that came out and compare to what you put in. These modern bearings sure beat the hell out of poured babbit,so convenient. One at a time,do not mix up the nuts and bolts,all the caps go on the same way,mark them first. Have a look at the crank seals for signs of leakage,the front important because the replacement means an engine drop. After you button it up,make a plan to heat the new oil and prime the system while rolling the crank 720*. Make #1 TDC on compression,plant the distributor and set initial,crank without spark,looking for oil pressure,add spark and start. Because you have ensured the carb is in top shape,it should fire inside 7 secs. Listen intently for strange noises like bearings squealing or pistons hammering. Set the idle screw,set the timing on the light,allow to come to temp,set idle again,watching the oil pressure. Take it to 2K and back to idle,stepping up in 500 rpm steps,repeat to 500 below redline. Allow to cool,restart and step up again,and if all is well,go for a drive,oil pressure noting. Tune for winter and summer,noting the new oil consumption,sniff the tailpipe at the dyno shop. Running a high performance engine,a constant r+r of the wear surfaces makes for cheap fun power. / From what I can see,those rollercam 350s in Newcastle should slip right in,the intake bolt pattern might be different though. Two bolts on each side in the center.Have a look at yours and those with pix.Note the numbers of all the blocks and heads. Run that past Renegade,they have solutions.I'm not sure about your waterpump mounts. / |
Justinp71 |
Feb 12 2016, 11:22 PM
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#54
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Senior Member Group: Members Posts: 1,582 Joined: 11-October 04 From: Sacramento, CA Member No.: 2,922 Region Association: None |
when people say a sbc can be reved to 6500 or some other number, do they mean it can be run for 15-30 mins at that rpm or do they mean that it can be screamed to that number and then promptly shifted?? If you upgrade the oil system. Probably need a deep sump, I believe there are dry sump conversions too. My dad used to have a southwest tour race car with a chevy 350 he built it. 350's are used for racing all over. If you spend any money, buy an LS1! Save weight and gain power. If you really want to you can put a carburetor on them to, to keep the simplicity. |
mr914 |
Feb 13 2016, 04:25 AM
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#55
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914 Hillbilly Group: Members Posts: 576 Joined: 11-January 03 From: Lincoln NE Member No.: 131 Region Association: None |
Got just the motor to replace yours.
May require some metal fab. Nothing like doubling up (IMG:style_emoticons/default/biggrin.gif) Attached thumbnail(s) |
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