I think I was using a smaller deck height for my numbers since the stroke is longer on the 400
-18cc pistons should probably work regardless though.
CK5
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Rebuilt motor w/ broke pistons UPDATE: 11/13/13 1.5yrs later upgrade time!
- Thread starter dabomb6608
- Start date
-18cc pistons should probably work regardless though.
Alright, and do you think those areas between the cylinders look fine?
My father is outve town until later this afternoon. He said he wants to help me on the cost for the pistons and ypipe. As much as I would like to be able to pay for everything myself since its my car that I bought, I really appreciate his help and unfortunately need his help this time. I spent about $1000 on the rebuild less then a month ago.
So maybe the pistons will be ordered by tomorrow. I will also be ordering a new set of rod bearings since im sure they took a beating with the detonation and they arent that expensive.
My father is outve town until later this afternoon. He said he wants to help me on the cost for the pistons and ypipe. As much as I would like to be able to pay for everything myself since its my car that I bought, I really appreciate his help and unfortunately need his help this time. I spent about $1000 on the rebuild less then a month ago.
So maybe the pistons will be ordered by tomorrow. I will also be ordering a new set of rod bearings since im sure they took a beating with the detonation and they arent that expensive.
The heads looked fine after you cleaned them up from what I could tell from those pictures. I'd be surprised if you needed new rod bearings. You could have popped them off and inspected them. If they didn't look worn I wouldn't have replaced them. But since you already removed them and probably mixed the order up probably better to go ahead and replace them.
You might take a straight edge place it across those spots and see if you can slide a feeler gauge under.
By pounded out what do you mean? They were all in place and I did keep them in order all but maybe 2. But the thin whitish coating that was on them was off on the top and bottoms but wasnt near the sides were the cap and rod meet. Also a few of them seemed like they had "spun" or at least when I was trying to get them off they were spinning. The crank rod journals looked perfect.
Pound as in hammer them out which causes them to spin. They loose there crush in the rod. I would have your rods checked to.
The rods look fine underneath the bearings. You can still see the lines from when they had machine work done.
That is why I said they probably were fine. From the journal I could see in the picture it looked ok. If you had "spun" a rod bearing your journal more then likely would have been chewed up. You also probably would have seen a rod discolored from over heating. I think people misuse the word spun bearing to represent a lot of things.
Yea, I think they will be ok. Well my dad just got back from Ky. So I will show him my cart on summit and see what he says. We will most likely wait till tomorrow since its payday.
Here are the items in my cart.
ypipe: http://www.summitracing.com/parts/BIG-11102YFLT/
pistons/rings: http://www.summitracing.com/parts/UEM-KB147KTM-030/
bearings: http://www.summitracing.com/parts/SLP-8-2555CP20/
Totals out to about $667
Looks like the pistons are special order.
Here are the items in my cart.
ypipe: http://www.summitracing.com/parts/BIG-11102YFLT/
pistons/rings: http://www.summitracing.com/parts/UEM-KB147KTM-030/
bearings: http://www.summitracing.com/parts/SLP-8-2555CP20/
Totals out to about $667
Looks like the pistons are special order.
Update: Called Summit. They said I could order it tonight and the pistons could be drop shipped from the manufacture straight to me tomorrow. So I should have everything in 2-3 days! Only bad part was I ordered everything myself. So Ive got a minimum amount of money to my name right now haha. Dad will be transferring his half tomorrow.
Where you pistons forged? Were they made in the usa?
Correct. They were hypers, along with the ones I ordered tonight. I am unsure if they are made in the us or not. They are a Federal-Mogul product if that changes anything.
Now the ones I ordered this time are Keith Black pistons. Since Speed Pro didnt offer any dished pistons for the 400ci.
Now the ones I ordered this time are Keith Black pistons. Since Speed Pro didnt offer any dished pistons for the 400ci.
Ya seems kinda wierd to me. I looked up a 72 pontiac 400 on Jegs and Summit and both showed up flat top pistons. There are guys on here way more knowledgable then me especially when it comes to sbc motors. That just seems kinda odd to me though. Was octane that much higher in 72 that you could run flat tops? Or is the limited number of 400's relegated them to mainly performance motors that guys run lots of octane and high performance heads?
yeah gas back then was better before all the crap they added to the refining process, including but not limited to the lead.
That was exactly what I was thinking. I guess there just aren't enough people buying these kits. Which also explains why the dished Keith black pistons were like $490.
The reason I never questioned the flat tops that came with the last rebuild was because the pistons that were in it were like flat tops. So I figured it would be fine. Live and learn i guess.
The reason I never questioned the flat tops that came with the last rebuild was because the pistons that were in it were like flat tops. So I figured it would be fine. Live and learn i guess.
I'm thinking the 400 was such a limited motor that the only people that build them anymore is the preformance guys. So that is why you see the flat tops and nothing else. I'm basically asking the question for you. I don't know the answer but someone else might.
GMCSuburban2500
Registered Member
Thought he said it was a Small Block Chevy 400, not a Pontiac 400...
It is a small block. But it still holds true that they aren't getting built near as much as say 350s are or the lt/ls motors. Either way, I ended up with pistons so at least that's a plus. Even if they are alittle bit more $$$.
