TheBiz

iTrader: (45)

Alright, to make a long story short, I bought a short block from a gentleman on this board. It has been 5 weeks since payment, and I drove 4 hours to pick it up last night only to arrive and sit there and watch him put it together in front of me.

There are a couple things that I'm not happy with and those will be addressed later on in private. What I need to know is this....

It was supposed to be a zero deck height short block. Once the motor was assembled last night we checked TDC. The pistons come out of the cylinder .046. Thats too much. My heads are milled .025, and I have a rather large cam. The motor builder told me just to use a thicker head gasket. Like .070 thick! Won't my intake fit wrong? I had planned on using 7.035 pushrods. Will the thicker gasket change the fit of the top end, change the setup as far as pushrods and PTV clearance, and will it lower my compression.

Thought?

Sales2@Texas-speed

iTrader: (5)

With a piston out of the hole .046" you should be VERY concerned about pistons contacting the cylinder heads. Sounds like the cranks/rods/pistons aren't matched properly!!

bjamick

iTrader: (31)

.046 is definitely something to be worries about.. I wouldn't run that motor with your heads most definitely. Figure out where the problem is, maybe the pistons are wrong or rods are to long. Something is definitely wrong.

TheBiz

iTrader: (45)

He seems to think that the block was decked too far. I have the box for the pistons and the rods, and hey are stock height and length. I'm afraid that I now have a $2000 paper weight.

Thorny

iTrader: (14)

I would be making another 4 hour drive for a refund if I were you.

TheBiz

iTrader: (45)

Making the phone call now.

Sales2@Texas-speed

iTrader: (5)

What length rod and what is the compression distance on the piston (often notated as CD: on the piston labels)? That'll help figure it out. It's not too often you see a block decked .045" just for grins!

dheck

iTrader: (9)

I just talked to him. The piston part number is Mahle ls1340908f04. It is a Crower rod and I think it is a 6.100. I can't find any literature in the CD of the piston. I just can't imagine they'd block the deck .045...

Edit: It looks like the CD is 1.340

Sales2@Texas-speed

iTrader: (5)

If it's a stock crank, that would put your pistons out of the hole .011". Now if for some reason it was a 4" crank, the pistons would be out of the hole .20", which is highly unlikely from your measurements in the original post. BUT, if it's a stock crank, and a 6.125" rod with that piston, they be out of the hole .036". I'd guess that is the case here. Are there any markings/engravings on the rods to indicate if which length they are?

dheck

iTrader: (9)

They are just marked with an M5. I checked summit and they only have one Crower LS1 rod for me to go off of. It is a stock LS1 crank.

dheck

iTrader: (9)

So if it's a 6.125 rod and it's been decked +/- .010 that could be the problem.

Sales2@Texas-speed

iTrader: (5)

Wrong rods and maybe some block decking would be my bet at this point from the information provided.

dheck

iTrader: (9)

I have't seen the motor yet. When I do I will get more information. Appreciate all the help.

racer7088

A lot of this makes no sense? most of the OEM style replacements are for the 6.098-6.100 rod but they usually use a .945 pin. Maybe you have the 6.125 long rods with those pistons and they honed the small ends out to use your bigger pins? No matter what you are way in left field. You could have the pistons lathed down a little but I wouldn't take that much off. You have some mismatched parts or they went crazy on the deck.

Usually you mock that up to see where it is before you do anything else as fasr as decking anyway?

dheck

iTrader: (9)

We checked it over. It's a 6.125 rod. He bought the only LS1 pistons that fit that wrist pin. He got screwed pretty bad.

TheBiz

iTrader: (45)

That is correct sir! They are a 6.125 rod with a .945 Pin. Someone didn't measure while they were "working" on my motor. Seems to me that if a builder had 5 weeks to build a motor, he/they should have checked the blocks for cracks (found one), realized that they got 15 wrist pin clips instead of 16, and that the ROD WAS TOO DAMN LONG! But, no they realize these problems the night I'm picking up the motor, which is ironically the same night they were puting it together.



Anyone want to buy a 95 Trans Am Roller? Hard-top car with an LS Tubular K. I'll make you a great deal!

racer7088

Yep they probably weren't aware of all the different combos people sell and parts for these LSx engines and just assumed everything was right and ready to go. Then it was too late when they were already putting it together and they see the pistons are .046 out of the hole!

TheBiz

iTrader: (45)

You have a PM.