JDSfastGN
Well-Known Member
- Joined
- Jun 16, 2001
So a while back I posted this thread about finding my bottleneck. The car had been 10.61@127 in that post and I just wanted to update. The car can and does 60 in the mid to high 1.4s but driver issues and rushing at the line preventing me from getting there on this trip. So im still looking mostly at 1/8th mph and 1/4 mph
https://turbobuick.com/threads/trac...find-my-bottleneck.457655/page-4#post-3812441
I swapped to an SD chip setup, 4" intake with a 1" plenum spacer and, adjusted the governor and got a 5700-5950 shift point. I turned the boost up a bit and had it tuned for 30-32 psi at sea level but the altitude and density altitude seemed to have dropped that considerably once I made a pass up in Oklahoma. A few small issues prevented me from making more than 2 qualifying passes at the Buick vs Ford Shootout. The car ran well enough. On my first qualifying pass it went 10.69@128.66 with 27ish psi down low and 28-29 up top having to let out for the 1-2 shift for some reason when it went to 6200 and kinda laid over. The 2nd pass the boost controller seemed to hit its limit and dropped boost to 22 so it was a throw away.
In the finals I didn't get the chance to build much boost as I was trying to tree my opponent who sat there for what seemed like an eternity after I went and still ran me down by 30 mph. The car trapped 129.5 running 28-29 psi up top. timing was 19* throughout the run. Really close to 130. All powerlogger mph is off due to being on 28x9 vs my 315/35/17s that its calibrated for.
Soon after Oklahoma I hooked up a 2nd MAP sensor to the intercooler pipe right before the intercooler to see the pressure drop. At 28-29 psi it was only 2-2.5 psi drop. At 32-33 psi it was closer to 4 psi drop. You can see one screen shot attached.
So what my question here is, in February my engine spun a cam bearing. The block came back with no cracks so the cam tunnel is being line bored to fit the same bearing size as the outter bearings. My biggest concern is still the converter. Its a PTC 9.5 16 blade with a sprag. According to the TCI calculators slippage was around 12-13% on my passes. Should I consider getting it adjusted again? Ive been working on my dads silver T recently and his 17 or 18 blade PTC and it was 4.5% at 130 mph on 26" street tires and running 6000 rpms. His has a 3.42 rear gear vs my 3.23. His car makes similar power to mine and our 80-120 times were very close. Should I really start considering going to a 3.42 again? Can that small amount of gear difference have that big of an effect?
I don't have any backpressure data but plan on having a bung welded into my new to me TA headers I picked up. Not sure if there's enough data to determine much but while the car is down and the engine is out I figured Id get some ideas.
https://turbobuick.com/threads/trac...find-my-bottleneck.457655/page-4#post-3812441
I swapped to an SD chip setup, 4" intake with a 1" plenum spacer and, adjusted the governor and got a 5700-5950 shift point. I turned the boost up a bit and had it tuned for 30-32 psi at sea level but the altitude and density altitude seemed to have dropped that considerably once I made a pass up in Oklahoma. A few small issues prevented me from making more than 2 qualifying passes at the Buick vs Ford Shootout. The car ran well enough. On my first qualifying pass it went 10.69@128.66 with 27ish psi down low and 28-29 up top having to let out for the 1-2 shift for some reason when it went to 6200 and kinda laid over. The 2nd pass the boost controller seemed to hit its limit and dropped boost to 22 so it was a throw away.
In the finals I didn't get the chance to build much boost as I was trying to tree my opponent who sat there for what seemed like an eternity after I went and still ran me down by 30 mph. The car trapped 129.5 running 28-29 psi up top. timing was 19* throughout the run. Really close to 130. All powerlogger mph is off due to being on 28x9 vs my 315/35/17s that its calibrated for.
Soon after Oklahoma I hooked up a 2nd MAP sensor to the intercooler pipe right before the intercooler to see the pressure drop. At 28-29 psi it was only 2-2.5 psi drop. At 32-33 psi it was closer to 4 psi drop. You can see one screen shot attached.
So what my question here is, in February my engine spun a cam bearing. The block came back with no cracks so the cam tunnel is being line bored to fit the same bearing size as the outter bearings. My biggest concern is still the converter. Its a PTC 9.5 16 blade with a sprag. According to the TCI calculators slippage was around 12-13% on my passes. Should I consider getting it adjusted again? Ive been working on my dads silver T recently and his 17 or 18 blade PTC and it was 4.5% at 130 mph on 26" street tires and running 6000 rpms. His has a 3.42 rear gear vs my 3.23. His car makes similar power to mine and our 80-120 times were very close. Should I really start considering going to a 3.42 again? Can that small amount of gear difference have that big of an effect?
I don't have any backpressure data but plan on having a bung welded into my new to me TA headers I picked up. Not sure if there's enough data to determine much but while the car is down and the engine is out I figured Id get some ideas.