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rebuilding the 454 from hell

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#61 ·
Not dirt. Those are scuff marks.
You will probably see similar vertical marks on the pistons.

If you can even slightly feel those with your fingernail, then if it were my motor, I would bore it.

Also there is a visible ridge there at the top of the bore. If you can feel it with your fingernail, then I would bore it.

Did your mechanic hone that with a ball hone? That's what it looks like from the pics.

Kent
 
Discussion starter · #62 ·
Mudball, thanks for the info,I don't know if he used a ball hone,but i'll ask. Would there be a problem with the hone job if he did use a ball hone?
I was warned by the brains of this forum not to rebore to .070'' [cylinder wall's are getting a bit thin]
Could re- honing those cylinder's walls get rid of the scuff marks? and would doing this effect the rings and pistons in any way?
.......................................................................................
A QUICK RECAP
with this module that i have, which i'm assuming is for a V6, would i need to replace it for a V8 module? or would the Crane HI-6M ignition box correct or compensate this problem?

THANKS


:)
 
Discussion starter · #64 ·
Stringray69,

This is a picture of the distributor Module. On the back it says 2094.

Image


On page 3 it says the Thunderbolt IV is stamped V8 24. With the crane HI-6M I don't need the Thunderbolt IV but this distributor module is what I am concerned about. Would this distributor module affect the timing if it is the wrong one?

SYMPTOMS:
-low vacuum reading 10"
-curb idle set in to far
-plugs foul at idle
-gas passing the rings

Thanks
 
#67 · (Edited)
man-of-war said:
thanks for the replies, i would look into the ring gap with the mechanic. i ask the mechanic about the stroker crank for my engine,but he said that i'll need to replace my pistons to stroker pistons.he said my existing 8.5 to 1 KB are to tall :rolleyes:
with this module that i have, which i'm assuming is for a V6, would i need to replace it for a V8 module? or would the Crane HI-6M ignition box correct or compensate this problem?
here are some pic of the block, the vertical lines my mechanic said its dirt?...

Image



Image



Those are indeed scuff marks and serious ones too...
The just lose every compression you have.
Believe me I´m an former machinist, bored plenty of cylinders that look like that.
You need to bore or get a new block..you can go with a 2 bolt block and take the 4 bolt saddles on that one.
Bore the required holes, line hone the block and rebuild everything, I´d go now with a 4.25 crank, with proper pistons to go with that crank and those 781 heads you got.
Slap a good intake on top of it a somewhat stout roller cam at like a Crane H-286-2 up and you are at 600hp with a 850cfm rated carb. (I´d choose the HR-306-2S-14 IG But thats a STOUT cam and wouldn´t recommend it for nothing but the serious ones
)
I´d say those pistons are somewhat shot too..you can prolly use them in another project if they measure up but obviously they have somehow taken a beating, might be wrong ringgaps or detonation too or then just wrong cylinder to piston clearance.
If the skirts on them have warped the might crack the someday and you´re back to Square 1.
Whatever, that is a EDITED from the former engine builder IMO or then just a sales rebuild.
Click to expand...
 
#68 ·
man-of-war said:
Mudball, thanks for the info,I don't know if he used a ball hone,but i'll ask. Would there be a problem with the hone job if he did use a ball hone?
I was warned by the brains of this forum not to rebore to .070'' [cylinder wall's are getting a bit thin]
Could re- honing those cylinder's walls get rid of the scuff marks? and would doing this effect the rings and pistons in any way?
.......................................................................................


THANKS


:)
Click to expand...
No proves just that the ball hone is used when light honing is done...meaning a second rebuild when something goes wrong soon after the rebuild.
You can´t Hone that much to get the scuffs out, period.
70 over is too much I´d say.
A new block is cheap insurance.
 
#69 ·
Look for a squarish electronic module, that would have been maybe on the original riser bracket.
-----------------------------------------
Consider a new machinist.

I'm thinking he doesn't have or know how to use, an actual Sunnen or equivilant, cylinder honing machine.

LOOKS like you may need to go up one oversize, on piston/bore size. DO NOT get crazy with adding compression.

Is that a ridge in the top of the bore?

Do you have a spec sheet that shows WHAT he did, size/clearence wise?

Is this fresh or salt water use?
 
#72 · (Edited)
Stingray69 said:
Look for a squarish electronic module, that would have been maybe on the original riser bracket.
-----------------------------------------
Consider a new machinist.

I'm thinking he doesn't have or know how to use, an actual Sunnen or equivilant, cylinder honing machine.

LOOKS like you may need to go up one oversize, on piston/bore size. DO NOT get crazy with adding compression.

Is that a ridge in the top of the bore?

Do you have a spec sheet that shows WHAT he did, size/clearence wise?

Is this fresh or salt water use?
Click to expand...
If he is a Machinist he sure Knows how to use a Sunnen Cylinder King (CK-1X) onether thing does he feel to go with the hassle.
If the engine has been recently rebuilt and something went wrong a ballhone would do.

On the other hand the Sunnen does´nt either have a straight upright hone arm movement and do in fact make a banana like movement. So they hone like that too.
Nothing to consider thou but there are other types of Hones too that go up and down straight.
 
Discussion starter · #73 ·
FTM, O/B i'm sorry, but is it the clear line with the PCV on it? if so no I tap the edelbrock carb to clear up some serious blow by.
Stingray69,no he did not give a spec sheet.
there's no ridge at the top of the cylinders .this engine only had 12hours of run time from the time it was rebuilt.thats all breakin time :angry1:
The boat was only ran in lake Ontario water .

this is my mechanic www.mississaugaengines.com
 
#75 ·
OK, time to measure piston to cylinder clearance.

Take a standard mic and measure your pistons on the skirts. Measure up and down the skirt from the oil ring to the base. You will find a max measurement point on each piston.

The scuffing on the pistons will be apparent with this measurement!

Almost all pistons are egg shaped, so measure across the skirt that has the protruding part down into the bore. This is generally the widest point.

Then take a bore gauge, basically a dial indicator with 90 degree attachments. Stick it down the bore and see what you get bottom to top, then move it 90 degrees to the bore and do it again. That will tell you if they are round. If you don't have anything other than an out of round measuring gauge, then put that on the same mic that you measured the pistons with and you will see the clearance.
===
I know, you wonder...

I founded Precision Engine Service in north Austin about 30 years ago. It's an automotive machine shop that I sold in 1978. It still exists!!!

I have had nothing to do with machine work since, though. I went into high tech! Every once in a while, I feel the need to say something that comes from old knowledge...

Sorry for the ramble.
Kent
 
Discussion starter · #76 ·
Mudball, hold those thoughts for now.I'm getting the engine guts tomorrow. that block is junk.
1] I PAID FOR A 454BB I GOT A 427
2] THIS ENGINE BLOCK HAS HAD IT'S DAYS, NOT FOR MARINE USE.

I'M ON A HUNT FOR A USED 454 Block. what bore size should i look for.
THANKS
 
#79 · (Edited)
Yes thats the Standard bore.
Got to any Truck or auto dismantler and get your block.
Or if they sell you a complete junk engine pull at least the heads off and see if it turns over.

you can if you are lucky get a 80´s Truck 454 that has 781 or 049 heads...I did a year ago.
 
#80 ·
Time to start thinking--clean slate.

You are not going to be using your pistons, I don't think.

I don't know what the current status is with your heads, aren't you already in a different set of large ovals?

This is the perfect time to jump up in cubes to a 502. You can build milder and STILL have more torque, or if you cam it aggressively, have a lot more power than you were originally aiming for, with reliablity.

I think your builder is an a-hole. HE got you into this!

Find someone else!
 
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