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Discussion Starter #1 (Edited)
Ok..I know there are some greedy bastages out there secretly testing the limits of the stock bottom end still, but normally don't admit what you are running. So..understand nothing will be held against you..ie don't try this at home...and you won't be judged..it's your machine to thrash.. If you are a racer who don't want to let it out..well...that sucks lol. Tell us anyway..you know you want to brag...
With that said..is what boost are you running on the stock bottom end(rods and crank)? Indicate CR and piston brand if not stock pistons,rev limit ,octane and AFR..
Someone out there is running what would be considered "crazy" boost on the stock bottom end..I know it..let's here it.
If this has been covered sorry...just thought it might make interesting conversation.
 

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I ran my 09 S completely stock motor at 12 psi for a year with no problems mostly in WY but two trips to Glamis and trail rides in AZ THEN ALL HELL BROKE LOOSE WHEN I WENT TO THE 860 BIG B0RE WITH STOCK CRANK!
 
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Discussion Starter #4
I ran my 09 S completely stock motor at 12 psi for a year with no problems mostly in WY but two trips to Glamis and trail rides in AZ THEN ALL HELL BROKE LOOSE WHEN I WENT TO THE 860 BIG B0RE WITH STOCK CRANK!
Roger that..understandable..the BB was likely making alot more power..
What Octane and AFR were you running on the stock S motor?
And what gave up on the BB? Crank? Was that at 12 psi and same AFR and octane?
 

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8.5 : 1 CP pistons, stock crank and rods, 13lbs boost. Pump gas with 1\2 quart of Torco for every 5 gallons, I am also running stock rev limiter and the A/F is right around 12.1. I do how ever have BD's EBC which allows me to have 2 boost settings. I run @ 6lbs for cruising and flip the 2 way toggle switch and its @13lbs.:ride::pint:
 

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I ran my 09 S completely stock motor at 12 psi for a year with no problems mostly in WY but two trips to Glamis and trail rides in AZ THEN ALL HELL BROKE LOOSE WHEN I WENT TO THE 860 BIG B0RE WITH STOCK CRANK!
Roger that..understandable..the BB was likely making alot more power..
What Octane and AFR were you running on the stock S motor?
And what gave up on the BB? Crank? Was that at 12 psi and same AFR and octane?
A/F was usually 11.8 (best for torque) 12.5 was the highest I would let it go. Started with a 50/50 blend of 91/110, then went straight 91 but in AZ and Glamis I ran 100 octane pump gas to be safe. Yes I twisted two cranks broke a rod on the third that was pinned. lost two cases and my big bore on the last crank.
 
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Discussion Starter #7
I ran my 09 S completely stock motor at 12 psi for a year with no problems mostly in WY but two trips to Glamis and trail rides in AZ THEN ALL HELL BROKE LOOSE WHEN I WENT TO THE 860 BIG B0RE WITH STOCK CRANK!
Roger that..understandable..the BB was likely making alot more power..
What Octane and AFR were you running on the stock S motor?
And what gave up on the BB? Crank? Was that at 12 psi and same AFR and octane?
A/F was usually 11.8 (best for torque) 12.5 was the highest I would let it go. Started with a 50/50 blend of 91/110, then went straight 91 but in AZ and Glamis I ran 100 octane pump gas to be safe. Yes I twisted two cranks broke a rod on the third that was pinned. lost two cases and my big bore on the last crank.

Thanks..good info.
Rev limit?
 
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Discussion Starter #9
8.5 : 1 CP pistons, stock crank and rods, 13lbs boost. Pump gas with 1\2 quart of Torco for every 5 gallons, I am also running stock rev limiter and the A/F is right around 12.1. I do how ever have BD's EBC which allows me to have 2 boost settings. I run @ 6lbs for cruising and flip the 2 way toggle switch and its @13lbs.:ride::pint:
Thanks..
Torco is good stuff for sure,i've ran up to 27 psi with 32oz to 5 gallons of 93 in my race car with no issues..16 oz to 5 gallons of 91 would put you at 102 ish..
2 boost settings is a good idea...one for me..one for the wife:rofl3:
I'd love to set up an electronic boost controller like I use on my turbo cars..you can dial in any boost level you want with the push of a button..pretty slick.
 
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Discussion Starter #10
stock rev limiter. I got 74 mph on gps at 6200rpm with the rage clutch I dont really thing I need more.
Nice..yeah that is plenty for me too..you'd need 7200 or so to do that with the stock clutches I imagine.
 

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I ran mine at 12.2 to 12.8 depending on the weather for over a year at 7k limit with no problems on pump gas and octane booster. It did have a cam and ported head, but stock crank and bore. MCX stage I kit.
 

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I've been told countless times that the 2010 cranks are much weaker than the previous years by many of our vendors and members. I found that out with 7psi, torco mixed to 97 octane, and 6400 rpm. It may be interesting to see what the 09's got away with vs. the 2010's. May or maynot see a pattern but I first hand would like to say the the 2010 guys take caution :scared2:
 
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Discussion Starter #13
I've been told countless times that the 2010 cranks are much weaker than the previous years by many of our vendors and members. I found that out with 7psi, torco mixed to 97 octane, and 6400 rpm. It may be interesting to see what the 09's got away with vs. the 2010's. May or maynot see a pattern but I first hand would like to say the the 2010 guys take caution :scared2:

That is interesting..I wonder why the cranks are supposed to be waeker on the 2010's? There hasn't been a crankshaft change that I am aware of?
How long did it last and how did it fail? ie did it happen all of a sudden or somewhat gradually...I guess what I am asking is looking back were there any warning signs?
 

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Lasted about 6 miles with the turbo. No real warning sign. The motor started vibrating real bad. At first I thought it was the clutch so I pulled the clutch cover off and sure as hell the whole primary was wobbling about 3/8" worth. Bent crank. Talk to Alan at richochet racing or do some searching on my posts. Big Mike mentioned he had heard this from quite a few people to me while I was in the install stage and turns out he was right. No real explanation but a few say that possibly the cranks are being manufactured from another vender as of the 2010 and late 09 models. Now I'm going billet and not looking back
 
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Lasted about 6 miles with the turbo. No real warning sign. The motor started vibrating real bad. At first I thought it was the clutch so I pulled the clutch cover off and sure as hell the whole primary was wobbling about 3/8" worth. Bent crank. Talk to Alan at richochet racing or do some searching on my posts. Big Mike mentioned he had heard this from quite a few people to me while I was in the install stage and turns out he was right. No real explanation but a few say that possibly the cranks are being manufactured from another vender as of the 2010 and late 09 models. Now I'm going billet and not looking back
That sucks! Well I already have more than 6 miles on mine with the turbo so I guess I am doing good lol.

I wonder if maybe there are just some defective cranks out there? Luck of the draw maybe? I haven't look to see who makes them..any markings/numbers on yours? I know my stock pistons were clearly marked Mahle.
The crank actually bent vs twisting,or both? Where is the bed at, the snout or center?
 

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I ran mxc mix racing fuel spacer and 11 psi stock crank. Just got my crank pinned and Im doing a BB kit lower the compression 8.1 going to run 13 psi boost still mixing racing fuel 10 gals 1/4 of it. I ran 12.5 fuel ratio in the turbo and 13.0 when not in boost gave me good numbers on the dyno. Might go a little richer on the BB to keep it cool 12.0 in turbo 12.5 not boosted takes a few horses aways but rather play it safe.
 
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Discussion Starter #17
So far no one here has ran over 13 psi on a stock bottom end....come on..I know some have let's here it..sucessfully or not..
 

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DogoX ran his for a long time at higher boost. I don't know the mileage or the boost levels though. He isn't on too often now that he has moved.
 

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I have ran 10 PSI with 50/50 91/112 stock 09 S motor. 12-12.5 AFR. We ride the UT and ID sand dunes primarly. I think the fuel is a bit of overkill but I would rather be safe than sorry. I have about 500 miles on it with nothing but smiles from everyone that gets in it.
 

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I believe bioaction ran 13psi or possibly higher before he twisted his crank. I think he was running race fuel.
 
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