95 LT1 rebuild
07-07-2009, 02:10 PM
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95 LT1 rebuild Well its time to rebuild my 1995 formula with the lt1, i ordered all the cam parts to swap in a cc503 with 1.6 NSA rockers now its time for the rebuiold kit, i have not torn down the block but im looking at one of these kits:
http://www.summitracing.com/search/P...s/?Ns=Rank|Asc
Question is main bearings and rod bearings, im doing a basically stock rebuild with a .30 over bore, and maybe a little head/intake porting. What are the undersizing all about and what would i need to go with, or is it best to wait until i tear it down and send it to th machine shop and wait for them to tell me? Any other guidance to the build would be very helpful. I got: Cam, headers, rockers, 7.16 studs, guideplates, hardened pushrods, new lt1 style lifters, springs, locks, retainers. I need a timing chain and the rebuild kit comes with the rings and gaskets etc etc. Anything else i will need before its said and done? fuel sys upgrade? etc?
http://www.summitracing.com/search/P...s/?Ns=Rank|Asc
Question is main bearings and rod bearings, im doing a basically stock rebuild with a .30 over bore, and maybe a little head/intake porting. What are the undersizing all about and what would i need to go with, or is it best to wait until i tear it down and send it to th machine shop and wait for them to tell me? Any other guidance to the build would be very helpful. I got: Cam, headers, rockers, 7.16 studs, guideplates, hardened pushrods, new lt1 style lifters, springs, locks, retainers. I need a timing chain and the rebuild kit comes with the rings and gaskets etc etc. Anything else i will need before its said and done? fuel sys upgrade? etc?
07-07-2009, 02:34 PM
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Undersize refers to the main and rod bearing journals on the crank. If these diameters are out of spec, the crank has to be machined. Once this is done, the journals are then undersized, so you need undersized bearings.
Don't order the kit until you have it torn down and have measured things, or you might have the wrong parts on hand.
Don't order the kit until you have it torn down and have measured things, or you might have the wrong parts on hand.
07-07-2009, 03:02 PM
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thanks guys, thats what i figured on is holding off until machining is done. what else will i need to finish the build? going to a 355 with a cc503 cam, my stock fuel sys should be fine right? And summit says i should get a 2500 stall with this cam, i feel this is a lil big for a street car, would sticking with my stocker for awhile (plan to get a 2000 int he near future) hurt the car in anyway? also on the timing chain whats the best to use, the stock chain is like 300 bucks from summit, but the summit billet cain is like 60 bucks. will it fit?
07-07-2009, 04:40 PM
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thanks guys, thats what i figured on is holding off until machining is done. what else will i need to finish the build? going to a 355 with a cc503 cam, my stock fuel sys should be fine right? And summit says i should get a 2500 stall with this cam, i feel this is a lil big for a street car, would sticking with my stocker for awhile (plan to get a 2000 int he near future) hurt the car in anyway? also on the timing chain whats the best to use, the stock chain is like 300 bucks from summit, but the summit billet cain is like 60 bucks. will it fit?
btw im using the same engine kit you are looking at
07-07-2009, 05:02 PM
#6
thanks guys, thats what i figured on is holding off until machining is done. what else will i need to finish the build? going to a 355 with a cc503 cam, my stock fuel sys should be fine right? And summit says i should get a 2500 stall with this cam, i feel this is a lil big for a street car, would sticking with my stocker for awhile (plan to get a 2000 int he near future) hurt the car in anyway? also on the timing chain whats the best to use, the stock chain is like 300 bucks from summit, but the summit billet cain is like 60 bucks. will it fit?
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07-07-2009, 07:32 PM
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its knocking, pretty sure its just lifters but sense im in the motor its got 140k miles and i want a fresh build, plus i want to do a cam and porting and i dont feel the 140k mile motor can handle a new cam, so its worth it to freshen it up.
07-07-2009, 08:13 PM
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Bore & hone .030" over, align hone, cut/polish the crank if you can (get a good stock one if you can't), recondition the rods, ARP rod bolts, Mahle 4.030" hypereutectic pistons (or forged aluminum if you have the $$$), magnaflux and heat tank the block. Have them install quality bearings and rings, you should have a stout 355 after that.
07-07-2009, 09:54 PM
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this isnt goig to be a race motor, its my DD, it see occisional stress but overall i baby it. i think thatd be over my budget honestly. tho i would love to do all that heh
07-08-2009, 12:19 AM
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Don't buy your rebuild kit from Summit. Find a reputable machine shop in your area and have them rebuild it to stock specs...
Bore & hone .030" over, align hone, cut/polish the crank if you can (get a good stock one if you can't), recondition the rods, ARP rod bolts, Mahle 4.030" hypereutectic pistons (or forged aluminum if you have the $$$), magnaflux and heat tank the block. Have them install quality bearings and rings, you should have a stout 355 after that.
Bore & hone .030" over, align hone, cut/polish the crank if you can (get a good stock one if you can't), recondition the rods, ARP rod bolts, Mahle 4.030" hypereutectic pistons (or forged aluminum if you have the $$$), magnaflux and heat tank the block. Have them install quality bearings and rings, you should have a stout 355 after that.
Nothing is wrong with that rebuild kit, its even priced really good. It addresses the weakness in the LT1 (non forged pistons) and lets you reuse the good parts (rods and crank) that are already tough enough for most mild builds. The only thing I don't like is that it only comes with a HV oil pump, but thats only an extra $40 at most to swap out.
To the OP, check the cylinders for wear and out of roundness (well have machine shop do it) because sometimes boring is not needed the factory rings wear very little on the cylinder walls. After that have pretty much everything else ss.slp says to the block and have it balanced for the heavier pistons.
For the stall, 2,500 would be the LEAST I'd run with that cam. As long as you get a stall with lockup it won't really hurt mpg's much.
07-08-2009, 08:00 AM
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alright, 2500 just seemed high i dont know alot about stalls but wouldnt that mean i have to rev 2500 rpms to get moving? or does the lock up mean it act like stock when im driving normally?
and the HV oil pump wont bolt up? i figured upon using my stocker if it was ok bc ive heard from everyone its already a type of HV.
and i already planned to do the .30 regardless of roundness.
Otherwise i think im better off buying the rebuild kit, w the forged pistons, bc unless i go to tampa or orlando to get this built and spend high dollars i dont really trust the guys here to know what to get for it. Got one of the best machineist in FL in my town..but id feel better knowing the parts i got are wrong instead of him.
and the HV oil pump wont bolt up? i figured upon using my stocker if it was ok bc ive heard from everyone its already a type of HV.
and i already planned to do the .30 regardless of roundness.
Otherwise i think im better off buying the rebuild kit, w the forged pistons, bc unless i go to tampa or orlando to get this built and spend high dollars i dont really trust the guys here to know what to get for it. Got one of the best machineist in FL in my town..but id feel better knowing the parts i got are wrong instead of him.
07-08-2009, 09:02 AM
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Good luck with that. Not everyone has a nice machine shop nearby or a sponsor from here that knows what they are doing, especially with LT's. Half the time you'll end up getting screwed over and would be better off to listen to a few of the guru's on here.
Nothing is wrong with that rebuild kit, its even priced really good. It addresses the weakness in the LT1 (non forged pistons) and lets you reuse the good parts (rods and crank) that are already tough enough for most mild builds. The only thing I don't like is that it only comes with a HV oil pump, but thats only an extra $40 at most to swap out.
To the OP, check the cylinders for wear and out of roundness (well have machine shop do it) because sometimes boring is not needed the factory rings wear very little on the cylinder walls. After that have pretty much everything else ss.slp says to the block and have it balanced for the heavier pistons.
For the stall, 2,500 would be the LEAST I'd run with that cam. As long as you get a stall with lockup it won't really hurt mpg's much.
Nothing is wrong with that rebuild kit, its even priced really good. It addresses the weakness in the LT1 (non forged pistons) and lets you reuse the good parts (rods and crank) that are already tough enough for most mild builds. The only thing I don't like is that it only comes with a HV oil pump, but thats only an extra $40 at most to swap out.
To the OP, check the cylinders for wear and out of roundness (well have machine shop do it) because sometimes boring is not needed the factory rings wear very little on the cylinder walls. After that have pretty much everything else ss.slp says to the block and have it balanced for the heavier pistons.
For the stall, 2,500 would be the LEAST I'd run with that cam. As long as you get a stall with lockup it won't really hurt mpg's much.
07-08-2009, 11:59 AM
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For the stall, it won't take all of 2,500 rpm's b/f you start moving, it will start moving at far less rpm than that it just won't stop "slipping (incorrect term)" until you hit 2,500 rpm.
Some people have had problems with the HV oil pumps sucking the pans dry under high rpm resulting in engine failure. They are really only intended for larger bearing clearances and or running an aux oil cooler where you'll lose a little pressure pushing it through the lines. That given, I'm running one with a 60 psi spring and have had it up to 6,500 w/o a single problem on the stock pan. I am running larger bearing clearances though so its kind of at your own risk.
07-08-2009, 12:52 PM
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I'm not in favor of the LT1's tight rod bearing clearances. If I ever re-do my 96 LT1 or my son's, I'll specify the rod bearing clearance be opened to .0025 and ARP rod bolts.
Trying to avoid the spun rod bearing syndrome I've been reading about so often on the forums.
Jake
West Point RCOKS!
Trying to avoid the spun rod bearing syndrome I've been reading about so often on the forums.
Jake
West Point RCOKS!
07-08-2009, 12:56 PM
#19
I'm not in favor of the LT1's tight rod bearing clearances. If I ever re-do my 96 LT1 or my son's, I'll specify the rod bearing clearance be opened to .0025 and ARP rod bolts.
Trying to avoid the spun rod bearing syndrome I've been reading about so often on the forums.
Jake
West Point RCOKS!
Trying to avoid the spun rod bearing syndrome I've been reading about so often on the forums.
Jake
West Point RCOKS!
I've hit the rev limiter of 6800 rpm a few times also.
07-08-2009, 02:07 PM
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I'm not in favor of the LT1's tight rod bearing clearances. If I ever re-do my 96 LT1 or my son's, I'll specify the rod bearing clearance be opened to .0025 and ARP rod bolts.
Trying to avoid the spun rod bearing syndrome I've been reading about so often on the forums.
Jake
West Point RCOKS!
Trying to avoid the spun rod bearing syndrome I've been reading about so often on the forums.
Jake
West Point RCOKS!
1. Weak rod bolts
2. Aluminum bearings
3. Poor oil pressure/not enough
4. Tight bearing clearances
All things that will increase the chances of spinning a bearing. I'd never run rod bearing clearances under .002" for anything that goes over 5k rpm. .0022"-.0025" are just about perfect for rods.