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#1
04-28-2005, 01:52 PM
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Ok, we got the new 465 put in the car and we tried to crank the engine over and we had no compression. We found out that the valves were staying open. The heads were resurfaced and it seems that the stock length pushrods are keeping the valves open since the heads sit that much lower. So IF that is the case, which is seems to be, I need to know what I'd need to make it an adjustable valvetrain so we can get this engine started
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#2
04-28-2005, 01:52 PM
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Ok, we got the new 465 put in the car and we tried to crank the engine over and we had no compression. We found out that the valves were staying open. The heads were resurfaced and it seems that the stock length pushrods are keeping the valves open since the heads sit that much lower. So IF that is the case, which is seems to be, I need to know what I'd need to make it an adjustable valvetrain so we can get this engine started
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#3
04-28-2005, 02:15 PM
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You need new pushrods.
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 frittering and wasting the hours in an off hand way.... 1969 GTO, 455ci, 230/236 Pontiac Dude's "Butcher Special" Comp hyd roller cam with Crower HIPPO solid roller lifters, Q-jet, Edelbrock P4B-QJ, Doug's headers, ported 6X-8 (97cc) heads, TKO600, 3.73 geared Eaton Tru-Trac 8.5", hydroboost, rear disc brakes......and my greatest mechanical feat....a new heater core. 
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#4
04-28-2005, 02:16 PM
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But I don't know how much the heads were shaved so I don't know how short to get?
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#5
04-28-2005, 02:37 PM
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Get a set of polylocks, or Summit Kool nuts.
This will allow you to properly adjust the rockers with out bottoming the rockers on the studs.
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Its ok to giggle and snicker, Dont laugh and point |
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#6
04-28-2005, 03:18 PM
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If the pushrods are in fact too long it might not be a good idea to fire the engine off, because you will have some pistons hitrting some valves, and this is never a good thing.
Go to the local engine shop and see if they have an adjustable push rod checker you can use, if not order one from Summitt and use it. Dont get in a hurry and see your investment go down the tubes. Mike |
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#7
04-28-2005, 04:16 PM
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<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Ollie:
Get a set of polylocks, or Summit Kool nuts. This will allow you to properly adjust the rockers with out bottoming the rockers on the studs. </div></BLOCKQUOTE> So do I just need the differnt nuts or do I need new rockers too?
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#8
04-28-2005, 07:16 PM
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Do as LouisianaGuy suggested. Check your pushrod length.
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frittering and wasting the hours in an off hand way.... 1969 GTO, 455ci, 230/236 Pontiac Dude's "Butcher Special" Comp hyd roller cam with Crower HIPPO solid roller lifters, Q-jet, Edelbrock P4B-QJ, Doug's headers, ported 6X-8 (97cc) heads, TKO600, 3.73 geared Eaton Tru-Trac 8.5", hydroboost, rear disc brakes......and my greatest mechanical feat....a new heater core.
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#9
04-28-2005, 07:19 PM
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shouldnt this not be an issue if its a hydraulic set-up...? something else doesnt sound right
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'74 formula 400, w/shaker (3 scoops) black deluxe interior, '70 406 balanced assembly, .30 trw slugs, moly rings, 4x heads 2.11/1.77 stainless valves, ra 4 cam, e-rpm intake, holley 750 vac. sec, msd hei, hooker headers w/ dual 3'' flowmaster 50 series ending at axle, t400 w/ GM6 convertor, transgo shift kit, b&m starshifter, 3.08 gears, centerlines, 265/50-15 bfg's rear and 235/60-15 front...yes im over cammed but it is still very fun... |
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#10
04-28-2005, 07:27 PM
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You need to have the correct pushrod length no matter what type of lifters you're running. Otherwise the valvetrain geometry will be off, causing rapid valveguide wear and other problems.
Check this out: Pushrod length and valvetrain geometry.
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1964 Tempest Coupe LS3/4L70E/3.42 1964 Le Mans Convertible 421 HO/TH350/2.56 2002 WS6 Convertible LS1/4L60E/3.23 |
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#11
05-02-2005, 07:08 AM
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I bought the Comp 9.136" pushrods. Is that not the correct length? How do I know what size to get?
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#12
05-02-2005, 07:47 AM
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The easiest thing to do is to get a kit from Nunzi's in NY that have the screw in rocker studs with nuts. The kit is about $30 and then you can adjust everything. This is of course assuming you have screw in rocker studs if you do not you then need to get custom size push rods. There is a way to determine the push rod size but the method eludes me now I will look for a link for you. Nunzi in NY could answer this in seconds and he usually will talk to people.
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#13
05-02-2005, 08:30 AM
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Crane Kool Nuts are about 30 dollars and will make your vavletrain adjustable. They are stepped on the inside to fit over the stock bottleneck studs. They have the hex positive locks on top as well. Replacing with 7/16 studs would be a heavy duty and costlier fix.
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#14
05-02-2005, 09:03 AM
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Use the Poli locs/cool nuts and then reset . Turn engine over by hand and make sure that the stock pushrods make the rockers stay centered on the valve stems. They will go off center a tiny bit but this is normal. Also check for side clearance with the pushrod and inner part of pushrod hole.
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#15
05-02-2005, 09:24 AM
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Hi,
You didn't mention what ratio rockers you are using. If 1.6:1 or greater your heads need the pushrod passages ground out on the stud side to prevent the pushrods from rubbing. This might be the reason your valves are staying open. Mike
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1968 Pontiac GTO 462CID, 4-Speed Manual, 3.55 rear. Aleutian Blue exterior, 219 Teal Blue interior. Chrome bumper, AM & 8-Track and Rally II Wheels |
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#16
05-02-2005, 09:44 AM
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in addition to getting an "adjustable" valvetrain, you will most likely need to get a different length pushrod. a pushrod length checker is the best tool for this job..
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************************************* 1968 Lemans. 37,000 original miles. GTO clone. 462ci/KRE 290 heads. UltraDyne 280/288 Solid/850 Qjet by Cliff/Performer RPM/TSP 9.5" in TH400/8.5" 3.42 gears/3950# Race weight/12.58@106 at Bandimere speedway high altitude |
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#17
05-02-2005, 06:21 PM
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1973firebird, nobody has come right out and said it but if you don't know how to check you have the right valve train geometry before firing your new motor, you maybe should get some professional help. You can do some serious damage to the top end and maybe the valves and pistons. Hope you don't take this advice badly.
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