Destroking - Facts or fiction

All I know is Don Cruz told me years ago that when he went 109 "Stroker" he went 2 tenths faster in the 1/4. Same combo just a stroker. Im sure there are all kinds of opinions and combos to make an argument for either and maybe with todays Turbo's its not apples to apples but I would think more CI means more power. Sure seems to be that way with a Stage or TA motor.
This is what started my original thought. I noticed somewhat of a trend for a majority of stroked 109 blocks, that don't seem to put down a significant amount more power for the added cubes. 4" bore blocks seem to do much better. I may be totally off base, and realize there are always exceptions.
 
This is what started my original thought. I noticed somewhat of a trend for a majority of stroked 109 blocks, that don't seem to put down a significant amount more power for the added cubes. 4" bore blocks seem to do much better. I may be totally off base, and realize there are always exceptions.

A 4" bore is going to pay dividends. There's more room around the valves, and you can go bigger on the valves. Better airflow, more power.
 
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Then thats really scary lol Any new additions to ur beast? Might be making my way down the Yorktown on Sunday. U shud meet me there. like 7:30 or so. Lmk

Actually, I think that’s an old photo of me!

I was much better looking then.
 
One thing that is 100% true about destroking is strength. I have never seen a rod bent or broken shorter than a 6" regardless of the type (style) or crank broken shorter than a 3.40" including BMS in a stage motor. Even tiny 209/218 cu inch aluminum INDY blocks handled 9,000+ rpm races contiuously. I knew of a racing team that had the same 3 engine short blocks their entire racing career. They had a few sets of heads and seemed like a couple hundred cams but the valvetrain was solid. I am glad that we are having performance discussions again. I said before on a previous topic that we have had the components to go really stupid fast for a very very long time, around 1984 or 85. We have been running engines from 209 to about 281 cubic inches. A couple of different blocks, heads, rods and turbos ( for some) but the same Buick spirit. No one on the Buick community could have ever imagined that a 109 , production style headed, 67mm turbo, stock stroked engine would be running times similar to an on center stage 2, production style headed, 3.625 stroke, PT-88 turbo'd machine from a couple of years ago. I still dont know how he did it but if that "top secret" recipe ever got out 109's would be taking some more lunch money again. Dan at DLS had once told me that stage heads were not needed because a production head can do the same job at a lower rpm given the same cubic inches. Speaking of that, I wonder has anyone destroked a 4.1 to something really small and put production style heads on it? :unsure: I think I have a 2.90 stroke BMS crank and a few raw forgings around here some where..........
 
rag231 I really enjoyed reading about some of your accomplishments in the other thread, too often we see screen names and don't know their background. Newer members would cringe if they knew how fast some of the older members have been but just don't brag about it.

I'm glad you brought up Dan Strezo because he is honestly 1 of the 2 smartest Buick guys that I know.
 
rag231 I really enjoyed reading about some of your accomplishments in the other thread, too often we see screen names and don't know their background. Newer members would cringe if they knew how fast some of the older members have been but just don't brag about it.

I'm glad you brought up Dan Strezo because he is honestly 1 of the 2 smartest Buick guys that I know.
link to this "other thread"?
 
One thing that is 100% true about destroking is strength. I have never seen a rod bent or broken shorter than a 6" regardless of the type (style) or crank broken shorter than a 3.40" including BMS in a stage motor.
The biggest gains in power in the last 20 years in the pro stock community where realized when the distance between the crankshaft center line and deck surface was shortened. If only Buick made a v6 engine block with a shorter deck. Imagine if it also had 6 bolt mains. Man,wouldn't that be something? Oh well.
 
The biggest gains in power in the last 20 years in the pro stock community where realized when the distance between the crankshaft center line and deck surface was shortened. If only Buick made a v6 engine block with a shorter deck. Imagine if it also had 6 bolt mains. Man,wouldn't that be something? Oh well.


but they did
 
I said before on a previous topic that we have had the components to go really stupid fast for a very very long time, around 1984 or 85.
yup.2 old school turbos on a stage 2 motor and 7.50s way back in the day with the right car. the 109 stuff now runs great when setup right to me thats where the jump is 8/9 sec 109 is a reality now
 
The biggest gains in power in the last 20 years in the pro stock community where realized when the distance between the crankshaft center line and deck surface was shortened. If only Buick made a v6 engine block with a shorter deck. Imagine if it also had 6 bolt mains. Man,wouldn't that be something? Oh well.
They did it’s a Indy block .
 

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This is a great thread Jerryl. There is a lot to take away from this one to say the least. Now if I only knew which direction to go in when it comes time for me to build my new low 10 second engine :unsure:
 
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