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My last race of the year my dragster lost .3 and I finally got around to pulling it apart. Motor still ran before I tore it apart and I hope no bottom end damage was done because there is a lot of metal in the top end.
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Hope your pickup screen and filter caught the particles before they got circulated. The 355 Chevy I got in the Camaro had one lobe gone like that and the lifter was destroyed, but the bearings look good, so no pieces got that far. You might have the same luck.
Don
yep i seen that looks like your running comp lifters . i would go thru the engine when you lose a roller lifter lots of junk ends up on the piston skrits and piston walls. look like a small base cam how much lift are you running . some lifters have a short life with big cam s need to keep a eye on spring pressure .if a big cam you may want to think about a 903 or 931 lifter
They are Isky lifters. Going to completely tear it down to replace all bearings and check pistons and skirts like you said. I do not know the lift of the cam so I am going to have it measured a new custom grind done with new springs.
I bought this motor used so my fault for not going through it and freshening it up before racing it.
Pat what is a 903 or 931 lifter?
thats the size of the lifter body . crowers hippo lifters or PBM /Ersons have pin oiling or the isky red zoneQuote:
Originally Posted by burnout1969
look like a older set of T&D rockers . i hope you did not force that lifter thru the bore that hard on the lifter bore and if bronze bush then you can screw the bore up your better to cut the tie bar or button off lifter and push it down when cam is out .you will need to look at that lifter bore good
Finally getting around to pulling the pan and the heads off. Found some scratches only on the odd side and all were at the six o'clock position of the bore. My fingernail does not get hung on any of the scratches so they are not too deep. Did find some damage on a couple of pistons and rods from the lifter roller. Pulled one connecting rod cap to check bearing. Currently getting a new custom grind done by Erson and they will be supplying me with all my new valve train components (springs, lifters and valves). Off to the machine shop next.
them walls do not look good . thats from junk under the skirts from cam and lifter going a way . that is the load side so thats were bores get cut up .what helps stop some of this is preping the bottom of piston bores breaking the sharp edge at the bottom of bore . making sure the rings when filed that the rings have no burrs . back side of housing bore on rod looks like it should but as allways should be check if still round in the housing bore
I would agree with you, I was not happy to see them. The even side looks perfect just the odd side has these vertical scratches. You think a rebore is in order to clean them up?
Looks like a pretty rough hone job before---you will have to hone it to see where it cleans up before you order pistons for it---
some look like ring end gap cutting in the bore i did add to my last post about ring and bore prep hard to say if it can be clean up would be to do with some things like what the bore are like round tapper weres the piston to wall is at now after clean up its not hard to add .002 to the bore size after clean up .i cleaned up bores that were like this and more .so it gets down to how loose you can run piston to bore . alot of times if a guy wants to save his pistons theres clean up on them as well were your going to get smaller after clean up to as i get the steel out of the skirts with a file and sand paper if pistons are not collapse i use a piston knurler . i done this may time them and and fit them to the new size on the bore .. look at your valve springs shims can cut walls up to any sharp bits that can get in the oil will be seen on the walls
Got my new cam specs in, got a custom grind from Erson since they just a couple of minutes from my work. I had the old cam measured first.
Old and new cam specs
yep Erson grind most all my custom grinds .for customer builds .low lift cam should be EZ on valve train parts
Looks like the cam bearing walked too, what could cause that?
Nope i would say they cut the block for a thrust bearingQuote:
Originally Posted by burnout1969
Pat, would they do that because of the gear drive? It has a milodon setup.
well yes but there is some guys that machine the block to for chain set toQuote:
Originally Posted by burnout1969
Finally got around to pulling the pistons and crank. All the rod and main bearings look fine but the piston skirts are looking beat up. Looks like a lot of the material from the lifter did embed itself in the piston skirts. The crank is a 4.25 crower piece and is 010.
there is some things about this engine when built you need to look at abit better lifter tracking is one thing .them pistons are hurt there not much that can be done less you clean all the steel out of the skrits and there is abit of it thats all them small black specks and knurl them .but thats hard to say not having them in my hands so if you fine someone that will or can knurl them or knows how to fit them there junk .every thing i posted about the bores still stands .prep of bores and rings must be done .
Pat, I bought this engine used so now that I have it apart it is going to be rebuilt with all good parts and whatever needs to be done as far as machine work goes. I am going to get new pistons now because all of them have this damage (No need to cheap out now at this stage) just need to wait and see what the machine shop says about the cylinder walls to see about bore size. Thanks for your help and input on this.
Finally getting things done on this rebuild. Block had to be taken out another .020 because of damage obviously so I went and saw Bill Miller (his shop is local) and am having some custom pistons made. He is not the way to go if you are doing a budget build, had a little sticker shock, but I am getting his wrist pins too. Erson is also local to me also and they helped me out with all new valve train components and were really great to work with. So hopefully motor will be back together at the end of the month.
all guys a deal with. you could of used a shelf pistons and would of been abit less ???Quote:
Originally Posted by burnout1969
Pat, from what I have read online (I know not always good/correct info) and my own research the heads I have would not work with normal open chamber pistons. I could be wrong, but that was the conclusion I came to and that is why I am having BME do the pistons. He just scanned my old Ross pistons and is making the new ones to the new bore size 4.580. I could not find many shelf pistons in that bore size, summit has some JE in that size and the price of those compared to the BME would of been pretty close. In fact we are going to use the JE rings because it was hard to find rings for the bore size. I also went with BME because it is nice to do business face to face and like to support local businesses when possible.
well i just did a 4.580 bore bow tie block. the guy had the pistons so i bored and hone his block and rings are $$ and from what he told me that JE is the only one that sells the ring s ? hard to say i never look in to it for him but told me top rings are $20. each.i told him to look in to a total seal rings as in the past they have had off size bore rings . any ways i would of used a 4.600 bore piston i do not know what chamber you have but i sure something could of been made to work less you have a odd size rod and strokeQuote:
Originally Posted by burnout1969
OK, well I am back. Got the short block together and now I have some piston to valve clearance issues. The new pistons were made from the old pistons, Bill Miller I guess just copied the dome and valve cut outs. So we clayed the heads with the old head gasket (.051) and the cam straight up I only have .042 on the intake and have .135 on the exhaust and a quench of .065. We did retard the cam 5.5 degrees to just check the piston to valve clearance and of course we did gain on the intake around .020 but that does not give me .080 which I have read is the minimum you want for the intake valve to piston clearance. Also, since this is a custom ground cam I want to install it straight up and not mess with the cam timing.
So the plans are to cut the intake relief another .080 and also go with a .031 head gasket to get a .045 quench which would give me some extra space for the intake and maintain a minimum .100 on the exhaust and also give more compression. I heard that .035 is the minimum for the quench?
Am I going down the right road with this or is there something else I can do or should do?
Finally got the motor back together and it runs awesome. It is much more responsive with the new cam. I had BME cut the intake reliefs a bit for my clearance problem, they ended up taking out another .050. Here are a couple of pics and a video.