What will my shortblock take??
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dr_frankenstein
Mad Scientist
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depends on your tuning abilitys.
a few stock blocks have turned numbers in the 10s...
whats your skill level?
A.j.
a few stock blocks have turned numbers in the 10s...
whats your skill level?
A.j.
138-140mph in the quarter for a while if there is no detonation.
Skill level... OK I guess. Turn it up a little at a time and keep the 02 millivolts in the high 700's then repeat. I keep the timing pretty conservative. From what I've seen the guys running fast on stock rotating assemblies are not using a lot of timing on pump gas/ alcohol. Seems like the faster pump gas cars are only using at or slightly more than 20*s in 3rd gear.
At 26#s of boost I'm not seeing any knock with what I believe to be ~ 20% of fueling through the alcohol kit and 02 recall on scanmaster showing 790mv
(chip fuel trim is for 16#, so absolute pressure there would be 30.7# I added 7% through chip, so that should provide gas fuel for 32.8# absolute... 26#s of boost would be 40.7# absolute, so I've got ~8 pounds of fueling from alcohol)
By-guess and by-golly numbers give me the assumption that the engine should be making about 700 hp at the crank with 26 pounds.
+1
I've seen a stage motor throw a scrap iron fit on a low 12 sec pass.......
I guess what I'm sayin is that detonation can kill a bad boy HD motor.... just think what it can do to a 109.
On the flip side..... you can run many 10 sec passes with a stock bottom end if you don't detonate it....
Comprende?
williambavila
William Avila (The Buick Guy)
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i have a similar setup in a 87 gn i will tell you tomorrow night going to the track
Just a Six??
OK! Who Farted??
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- Jul 4, 2003
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I would invest in a Power Logger along with the Scanmaster for ease of record-playback if nothing else.
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(chip fuel trim is for 16#, so absolute pressure there would be 30.7# I added 7% through chip, so that should provide gas fuel for 32.8# absolute... 26#s of boost would be 40.7# absolute, so I've got ~8 pounds of fueling from alcohol)
what book did you learn this from ?
a chip burned for 16# is just that 16psi boost, we dont deal in absolute nor does your boost gauge or you chip burner
your math logic of "added 7%" means nothing without factoring the injector size and its current duty cycle
the relationship between running 16psi and 26psi is not something you can just throw a percentage # at for fueling as efficiency goes down as psi goes up , if you run 26# and the a/f is lean and needs more fuel add it if you can
narrowband are almost usesless in determining an AF but they do let you know youve got fuel . 790 at 26psi could be 9s AF or 11's AF , with 11.3 AF at 26psi i saw 690mv on a narrowband O2 ,
i ran many runs at 25/24* all stock bottom end , iron heads in the mid 10s,
boost 26 first gear /22-24psi third gear , AF 11.3 (55%of 75#inj) with alky (dual nozzle M10+M15 at 150psi) I was displacing 15% of my fuel and IATs at 70-80DF
and arp hardware isnt going to do a thing for durability , the stock piston will give before the stock hardware
what book did you learn this from ?
a chip burned for 16# is just that 16psi boost, we dont deal in absolute nor does your boost gauge or you chip burner
your math logic of "added 7%" means nothing without factoring the injector size and its current duty cycle
the relationship between running 16psi and 26psi is not something you can just throw a percentage # at for fueling as efficiency goes down as psi goes up , if you run 26# and the a/f is lean and needs more fuel add it if you can
narrowband are almost usesless in determining an AF but they do let you know youve got fuel . 790 at 26psi could be 9s AF or 11's AF , with 11.3 AF at 26psi i saw 690mv on a narrowband O2 ,
i ran many runs at 25/24* all stock bottom end , iron heads in the mid 10s,
boost 26 first gear /22-24psi third gear , AF 11.3 (55%of 75#inj) with alky (dual nozzle M10+M15 at 150psi) I was displacing 15% of my fuel and IATs at 70-80DF
and arp hardware isnt going to do a thing for durability , the stock piston will give before the stock hardware
The motor has diamond pistons, so I'm not too worried there. Hey, I guess it doesn't take a genius to turn up the alcohol kit if it starts getting some knock.
As far as timing goes. From what I've seen the fastest pump gas/ alcohol car with a stock crank and rods claimed to be running 20* with an E.T. of 9.62
As far as timing goes. From what I've seen the fastest pump gas/ alcohol car with a stock crank and rods claimed to be running 20* with an E.T. of 9.62
If you plan on running the stock crank and rods hard you cant ever have any detonation or it will last about 1 second. You wont be making many 9 sec passes on a stock crank/rods engine even with no detonation. It will take it for a while if its dead on but it wont last one sec if theres any detonation. If you want to run 9's you should consider a forged crank and rods with at least steel caps and run a good block.
I don't think the car will go that fast. I don't think I'll ever run more than 27#s of boost. I'd rather run a little slower and not blow the car up. I'm really more curious about how much more an engine will take reliably with good pistons and fasteners. The motor has 0 knock, at least according to the recall button on the scanmaster. Car runs pretty strong. I'm going to take it to the track this Saturday.
I took it once before with the current motor and turbo and it went mid-Nineties on stock tires in the 1/8th on 21 pounds, but that was babying the car through first. That was also running through the stock intercooler and exhaust.
Since then I put in a roller camshaft, 23 row SLIC (had stock one before), 4" maf pipe (had stock one) 26# boost, Car is a lighter, etc... The car feels night and day stronger than it did, and to be honest I think it would have run 100 in the 1/8th before if it had been on a good tire.
I took it once before with the current motor and turbo and it went mid-Nineties on stock tires in the 1/8th on 21 pounds, but that was babying the car through first. That was also running through the stock intercooler and exhaust.
Since then I put in a roller camshaft, 23 row SLIC (had stock one before), 4" maf pipe (had stock one) 26# boost, Car is a lighter, etc... The car feels night and day stronger than it did, and to be honest I think it would have run 100 in the 1/8th before if it had been on a good tire.
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I have seen a 12 sec. GN grenade a stock block at mid-run.
Destroyed the block, crank and other parts including the trans.
Pushing a 25 year old stock short block at any level is a crap shoot - metal parts are subject to fatigue, especially the cast crank.
TURBOPOWERED68
David
- Joined
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I have seen a 12 sec. GN grenade a stock block at mid-run.
Destroyed the block, crank and other parts including the trans.
Pushing a 25 year old stock short block at any level is a crap shoot - metal parts are subject to fatigue, especially the cast crank.
posts like this scare the crap out of me
Its not really cast iron. Its cast nodular iron. Big difference. It wont fail till it has a crack in it. Which takes a long time to develop. It will flex and bend repeatedly and snap back into original dimension unless its been flexed to far where it will fail at a stress riser. I have seen stock cranks rub the center mains quite a bit from big cylinder pressure but still showed zero run out in the crank grinder. The caps showed little evidence of metal transfer where they meet the block. The rubbing of the bearings is from the crank flex under high cylinder pressures. If you plan on 135+ trap speeds id be looking at a forged crank.
I'm just not going to run it too hard. I don't have the time to start building another motor right now, and I've never even had this one to the track with a good tire. I really don't know how much further I'd try to go with the TTA. Once you go into the 9's the heads, downpipe, intercooler issues become more work than it's worth on a TTA, but then again I've already addressed a lot of the problems like the rear end and some other stuff. 
The car picked up a ton of power after I made this sucker and that was a typical problem area for a TTA
This going in the car was also a bonus!
If I were getting into turbo Buicks again I would have gotten a T-type.
The car picked up a ton of power after I made this sucker and that was a typical problem area for a TTA
This going in the car was also a bonus!
If I were getting into turbo Buicks again I would have gotten a T-type.
I'm just not going to run it too hard. I don't have the time to start building another motor right now, and I've never even had this one to the track with a good tire. I really don't know how much further I'd try to go with the TTA. Once you go into the 9's the heads, downpipe, intercooler issues become more work than it's worth on a TTA, but then again I've already addressed a lot of the problems like the rear end and some other stuff.
The car picked up a ton of power after I made this sucker and that was a typical problem area for a TTA
This going in the car was also a bonus!
If I were getting into turbo Buicks again I would have gotten a T-type.
Has anyone ran 9's with a stock block? I know ATR had a customer that did it over 10 years ago with a s2.
Shoot for 9.60. That would be a tough one
