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-   -   400 Stroker Build Documentary (https://forums.maxperformanceinc.com/forums/showthread.php?t=868547)

Tim Corcoran 08-15-2023 11:05 AM

I understand that my method may differ than others and may not be the "best" method, but I have never had a freeze plug leak and the sealing surface is not damaged or deformed using my method.

J.C.you 08-15-2023 10:57 PM

I used to restrict the lifter bores and noticed premature lifter scuffing and bore wear. Just my experience. Been using restricted pushrods and even restricted the rocker arm holes, jfyi. Your build good luck.

Don 79 TA 08-16-2023 08:18 AM

sorry if i didn't catch it, but are you going with a 4.25 crank or 4.5? if not 4.5 any reason?

Tim Corcoran 08-16-2023 04:49 PM

I am going with a 4.181 bore and 4.25 stroke. There are a few reasons why I would prefer not to go to a 4.5 stroke. With my heads having a 71cc combustion chamber it would bring my static compression way too high, of course I could of ordered dished pistons to get my compression down. A longs stroke like 4.5 puts additional stress on the crank and the block, I don't want to push my luck with an OEM block. Longer the stroke the faster the piston speed thus shorter ring and bore life, I already have increased piston speed using 6.8 rods that's a tradeoff for less side loading on the cylinder wall and better cylinder filling since it dwells longer at TDC. If I were building a monster engine with an aftermarket block I'm not sure even then I would go with that large of a stroke. Many have done it with good results in my opinion it's not the best choice for me. I'm not going for max power I'm trying to stay in the low 10 second range for a reliable long lasting bracket engine and I don't want to put in a cage and window net.

blueghoast 08-19-2023 03:54 PM

I like the 4-inch stroke there assome, kind of the best of both worlds
Just thinking out load. Good Luck.

GT

Tim Corcoran 08-20-2023 10:03 PM

4 Attachment(s)
The reason to fill your block with a block filler is to prevent flexing of the block which may compromise your ring seal and cause additional friction between the piston skirt and the cylinder wall. I started filling the block this week, the material I am using is from Race Engineering and it came recommended by some members here on the forum. It comes in a 25 Lb. bucket, you need to divide it in half and use half for each side, there is more than enough material to do both sides. I leveled the block by shimming my engine stand and got the block level in both directions. This is only the second time I have done this process, so I am far from an expert here. The other time I did this I used "Hard Block" and that was quite a few years ago. If you ever do this do NOT do it when it's hot as it may harden up VERY fast. When I did the first side it was very hot and it turned out to be a disaster, after mixing it started hardening almost immediately. I didn't even get half of the material in the block and it was hardening in the funnel and what I did get in didn't reach very far in the block. Mind you I was prepared and had everything ready in advance all I had to do is add water mix and pour.

I believe I made two mistakes; it was too hot (around 95 degrees) and I think I didn't make the mixture thin enough. I have a game room inside of my shop and it has AC, so I moved the operation into my game room and turned the thermostat down to 65 degrees and left it in there for 24 hours and got everything good and cold. This time I added more water and got it thinner and had my wife hold the funnel for me. Now I am re-pouring the same side to get a complete fill. With my assistant holding the funnel and me working fast with my thinner mixture in a 65 degree environment it was a success.

I believe that most people that do this only fill to the bottom of the water pump holes but based on the recommendation of my machinist I filled it to about one third of the way above the water pump holes. I am waiting for the negative comments on this as I am sure they will be coming. Since I used the other half of the material to finish the first side I had to order another bucket of material it should be here Tuesday. Once the block fill is complete it will be going to the machinist for the line bore/hone (to mate the new 4 bolt caps), boring/honing the cylinders and decking for a zero deck.

Tim Corcoran 08-20-2023 10:14 PM

1 Attachment(s)
One more thing I did while filling the block I used an air hammer with the pressure turned down to vibrate the block to eliminate any voids and help level the material out. If you do this don't hammer on the side where the cylinders are you could damage the block. I hammered it at the bottom where the motor mount pads are because the block is plenty thick there. I also used a firm wire and poked it into all the holes in the top of the deck to agitate the mixture. Maybe over kill but I wanted to make sure there are no voids.

Tim Corcoran 08-20-2023 10:37 PM

4 Attachment(s)
I will be re-using the same E-Heads I had on the 455 that was destroyed at Norwalk. These are 330 CFM heads done by Dave at SD Performance back in 2007. I have them stripped down and I removed all the carbon and scale from the ports (lots of work) and I will have them milled about .020 to get the compression to around 12.3. I checked the springs, they are still good so will re-use them. I removed all the carbon from the valves using a wire wheel they cleaned up pretty fast. There were a few bent valves that I have replacements for but the valve job looks really good so I will install new valve seals, lap in the valves and re-shim the springs and that should be it for the heads.

Stan Weiss 08-20-2023 11:03 PM

1 Attachment(s)
Quote:

Originally Posted by Tim Corcoran (Post 6448095)
I am going with a 4.181 bore and 4.25 stroke. There are a few reasons why I would prefer not to go to a 4.5 stroke. With my heads having a 71cc combustion chamber it would bring my static compression way too high, of course I could of ordered dished pistons to get my compression down. A longs stroke like 4.5 puts additional stress on the crank and the block, I don't want to push my luck with an OEM block. Longer the stroke the faster the piston speed thus shorter ring and bore life, I already have increased piston speed using 6.8 rods that's a tradeoff for less side loading on the cylinder wall and better cylinder filling since it dwells longer at TDC. If I were building a monster engine with an aftermarket block I'm not sure even then I would go with that large of a stroke. Many have done it with good results in my opinion it's not the best choice for me. I'm not going for max power I'm trying to stay in the low 10 second range for a reliable long lasting bracket engine and I don't want to put in a cage and window net.

Tom,
While increasing the rod length does change the piston velocity curve, where in the velocity curve are you looking at when you say velocity has increased? Peak velocity is actually reduced as you length the rod. You also move the point of peak velocity and where the rod and crank journal are at 90 degrees to each other farther ATDC.

Stan

slowbird 08-20-2023 11:44 PM

Quote:

Originally Posted by Tim Corcoran (Post 6449037)
I will be re-using the same E-Heads I had on the 455 that was destroyed at Norwalk. These are 330 CFM heads done by Dave at SD Performance back in 2007. I have them stripped down and I removed all the carbon and scale from the ports (lots of work) and I will have them milled about .020 to get the compression to around 12.3. I checked the springs, they are still good so will re-use them. I removed all the carbon from the valves using a wire wheel they cleaned up pretty fast. There were a few bent valves that I have replacements for but the valve job looks really good so I will install new valve seals, lap in the valves and re-shim the springs and that should be it for the heads.

Since you're running race gas, mill the heads and get compression up to 13.5-14. Might as well make running race worthwhile.

Tim Corcoran 08-21-2023 12:24 AM

Quote:

Originally Posted by slowbird (Post 6449051)
Since you're running race gas, mill the heads and get compression up to 13.5-14. Might as well make running race worthwhile.

Yeah I get your point but I am trying to duplicate my 455 engine because I don't really want to make any more power than I did before for a few reasons. I was already low 10's with the 455 engine. I know with more compression and a bigger cam would put me well into the 9's.

1. Don't want to put in a cage and window net
2. Currently running the largest tire that fits in the stock wheel well (28X10.5X15) MT drag slick and I don't want to tub it and if I go much faster I will need a bigger tire.
3. The more power you make the more parts you break so I will sacrifice speed for a longer lasting engine.
4. Bigger cam and more compression more RPM now I need to higher stall converter.
5. Bigger tire oh now I need to tub it, oh now I need more gear, now I am overpowering my suspension, and on and on...

If I had a much larger budget for my toy I'd love to go faster and faster but it's not in the cards

That's my plan and I'm sticking with it.

Tim Corcoran 08-21-2023 12:37 AM

Quote:

Originally Posted by Stan Weiss (Post 6449045)
Tom,
While increasing the rod length does change the piston velocity curve, where in the velocity curve are you looking at when you say velocity has increased? Peak velocity is actually reduced as you length the rod. You also move the point of peak velocity and where the rod and crank journal are at 90 degrees to each other farther ATDC.

Stan

It is my understanding that with a longer rod the piston dwells longer at TDC and gives more time for cylinder filling and this also increases piston speed at some point in the stroke over a shorter rod. I don't understand your statement that peak velocity is actually reduced with a longer rod or maybe my understanding is flawed.

chiefbigb 08-21-2023 09:53 AM

Stan is pretty smart. Your build is one that has been done by probably everyone in the race section 20 plus years ago. The higher block fill will probably net you higher oil temps and lower cooling system capacity. I hope it runs well and lasts many years.

blueghoast 08-21-2023 11:47 AM

I've got two motors that are hard blocked to the water pump holes
Both of these motors run cooler then any of my other engines.
On the street and at the track, I'm useaully running the motor in
the staging lane's to keep the temp up where it needs to be.

GT

chiefbigb 08-21-2023 10:38 PM

Do you monitor oil temp also?

Stan Weiss 08-22-2023 12:15 AM

5 Attachment(s)
These were done a number of years ago using the same bore and stroke with varying rod length.

Stan

Tim Corcoran 08-22-2023 12:58 PM

1 Attachment(s)
The hard block process is complete, the block is now ready for the machine work.
1. line bore/hone for the 4 bolt main caps
2. Bore/hone cylinders using a torque plate with main caps torqued in place
3. Mock up with pistons/rods installed on four corners to verify how much to remove from the deck to get pistons even with deck
4. Machine deck surface of block
5. Mill heads .022 to increase compression. Mill an equal amount on head and intake surface
6. Engine assembly

Steve C. 08-22-2023 05:24 PM

With Pro-Gram Engineering steel caps we used oversized dowels to ensure a tight fit.

https://butlerperformance.com/c-1459...owel-pins.html

I read that dowel pins are like fingerprints-no two are exactly alike.



.

blueghoast 08-23-2023 12:29 AM

Quote:

Originally Posted by chiefbigb (Post 6449315)
Do you monitor oil temp also?

No I haven't done that yet

GT

Tim Corcoran 08-23-2023 09:54 AM

Quote:

Originally Posted by ponjohn (Post 6447057)
How much weight does hard block add?

Around 20 lbs


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