Colipto's BP to K swap build thread
#124
Yep and looks like i just got a call from fab 9.. someone ordered those pistons...They do not have them available nor does anyone else - this seems like my bad luck keeps repeating itself.
I am at the point of bumping the compression to 9:1 with super tech pistons..
I don't want to go Wiseco even though I would be able to keep the lower compression.
I have less then 2 hours to decide.. i do not want to wait another month for lower comp pistons..
edit: going with 9:1 because of availability. ... Looks like I'll be reselling a set of 8:6 once i get the other two.
I am at the point of bumping the compression to 9:1 with super tech pistons..
I don't want to go Wiseco even though I would be able to keep the lower compression.
I have less then 2 hours to decide.. i do not want to wait another month for lower comp pistons..
edit: going with 9:1 because of availability. ... Looks like I'll be reselling a set of 8:6 once i get the other two.
Last edited by Colipto; 11-18-2016 at 03:20 PM.
#125
Operation rebuild is a go. Hopefully I'll have the block / head back in my hands by this week. The head has some bent valves apparently.
Also compression is 9.5:1 for the pistons, not 9:1. .. which I don't mind from the research I've done, it should still work fine for my build
Can anyone tell me otherwise?
I've spoken with the tuner who tuned it previously - I'm most likely going to give him another shot once its up and running as I don't 100% believe it is his fault, more my recklessness.
I will most likely tow it up there once i have the first startup all set so he can take a look at everything.
Also compression is 9.5:1 for the pistons, not 9:1. .. which I don't mind from the research I've done, it should still work fine for my build
Can anyone tell me otherwise?
I've spoken with the tuner who tuned it previously - I'm most likely going to give him another shot once its up and running as I don't 100% believe it is his fault, more my recklessness.
I will most likely tow it up there once i have the first startup all set so he can take a look at everything.
#131
for 9:1 or lower i could go to 84mm pistons but then that would be a rebore and more time... i could most likely go back 8:6 here too.
Is it really worth it ?
#133
Everything is still on schedule, looks like I'll be able to have her together by this weekend - the shop informed me they will have the block ready by tomorrow. Hoping for first start AGAIN by 11/27?
No time for slack..
Last edited by Colipto; 11-22-2016 at 05:39 PM.
#134
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I think it's foolish to put the wrong piston in the motor just to save the $150 in overbore costs. The 9.5s will be substantially more prone to detonation and you'll end up making a bunch less power on gas than you would have with the 8.6s.
You also need to throw the other two 8.6:1s away. You cannot sell those in good conscience. The detonation that killed two of your pistons wasn't isolated to only two of your cylinders.
You also need to throw the other two 8.6:1s away. You cannot sell those in good conscience. The detonation that killed two of your pistons wasn't isolated to only two of your cylinders.
#135
I think it's foolish to put the wrong piston in the motor just to save the $150 in overbore costs. The 9.5s will be substantially more prone to detonation and you'll end up making a bunch less power on gas than you would have with the 8.6s.
You also need to throw the other two 8.6:1s away. You cannot sell those in good conscience. The detonation that killed two of your pistons wasn't isolated to only two of your cylinders.
You also need to throw the other two 8.6:1s away. You cannot sell those in good conscience. The detonation that killed two of your pistons wasn't isolated to only two of your cylinders.
I'll be keeping the pistons as trophy's of my multiple failures.
Thanks
#137
I have 9:1 Supertechs, not 9.5:1. Yes, the motor is a lot more ping prone than I expected it to be, and topped out at 270 rwhp (200 kpa) on 95 octane due to ping.
I'm not sure if this is solely due to the piston choice, though. My previous built motor (which died from a throttle body screw) was also 9:1 supertechs, and it was way less ping-prone than the new one. I'm not sure what's causing the ping (one theory is excessive milling of the head), but certainly using 8.6:1s instead would have been a better choice in retrospect.
After going to straight 100 octane in the car it made 340 at 230 kpa before it started pinging.
--Ian
I'm not sure if this is solely due to the piston choice, though. My previous built motor (which died from a throttle body screw) was also 9:1 supertechs, and it was way less ping-prone than the new one. I'm not sure what's causing the ping (one theory is excessive milling of the head), but certainly using 8.6:1s instead would have been a better choice in retrospect.
After going to straight 100 octane in the car it made 340 at 230 kpa before it started pinging.
--Ian
#138
Okay.. I spent the past few days putting the shortblock together and dropping in the engine....
All that's left is connecting the turbo and inter cooler piping - I'll most likely have some dyno results this week. Realistically if i can get near 300hp on pump with this setup I'm okay with that.
All that's left is connecting the turbo and inter cooler piping - I'll most likely have some dyno results this week. Realistically if i can get near 300hp on pump with this setup I'm okay with that.