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Discussion Starter · #1 ·
Can anyone recommend the best way to get into the high 12's? I have a bone stock 9C1 (I hope we are welcome here?). I have been eyeing the turbo technology ss turbo kit in addition to the thought of cam/heads/intake/exhaust. I'd like to keep complete streetability. Also don't want to spend a lot of money but I do understand that getting a 4300 pound boat into the 12's requires at least a few grand. Also, nitrous is not an option unless it's the topping of a cake. Thanks in advance.
 
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Discussion Starter · #2 ·
As you can see from my sig. it is not that easy to get into the 12's naturally asperated. Turbo's and superchargers are a good way but you should really set up the rotating assembly for them. With 10.5 to 1 compresson on a stock LT1 it is not really a good idea to run them without lowering the compression. Which means building the rotating assembly for them with about 9 to 1 compression or lower. I will get into the 12's naturally asperated but it has been a long 2 year strugle and alot of mula :mad:
HVY SS
 
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Discussion Starter · #3 ·
Hey is that 10.5 to 1 compression like with the 58cc heads, I was told with the 64cc heads on my 9C1 1994 that the comp ratio is more like just under 9.5 to 1.

Nothing wrong with NOS, just seems like lots of persons dont use it correctly.

Getting these big ol rides into the 12's is hard, but hell put enough money into a load of bricks and even it will move pretty quick, Ford is proving that with the new Merc.

PS remember if your sitting in a Ford the jokes all around you!
 
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Discussion Starter · #4 ·
<BLOCKQUOTE>quote:</font><HR> PS remember if your sitting in a Ford the jokes all around you!
<HR></BLOCKQUOTE>

Well, since all of us are laughin if we're a ford rite now - ;) . It seems like the easiest way to get into the 12s is with the boost either turbo or supercharged, but i wouldn't want either without a built of motor.

Paul K.
 
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Discussion Starter · #6 ·
I'm not sure about our 94's, but the 95 was a 10:1 CR, not 10.5:1. Still high, but half a point makes a big difference. I'm not sure why the LT1 couldn't handle a turbo or supercharger with a stock bottom end.
 
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Discussion Starter · #7 ·
The problem is cylinder pressure. With more pressure going into a relatively high pressure chamber already you will possibly blow a headgasket. And the higher the Compression the higher the chance of spark knock. If you get spark knock on any power adder (nitrous, supercharger, or turbocharger) chances are you will have a 'sploded piston. The stock internals are not forged and can often give up the ghost in a high power application.
 
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Discussion Starter · #8 ·
The stock compression ratio on a '96 is 10.1:1 (4.00" bore, 3.48" stroke, 64cc head volume, 4cc valve reliefs, .027" gasket thickness, .025" deck height) Try it in any compression ratio calculator such as this one Ross compression ratio calculator. The aluminum headed Camaro and Vette engines ran 10.5:1. The factory service manual gives conflicting info on this with one page stating 10.1:1 and another stating 10.5:1.

I can personally attest to the fact that 10.1:1 is cutting it close for a turbo. It took me two years and 20,000 miles for the pistons to crack, but crack they did. I was running 7-8 psi with the turbo tech kit and had too much timing programmed into the motor following a PCM tuning session. The overly advanced timing caused detonation at redline and the "ring lands" on two pistons cracked. Unfortunately the pistons go before the head gaskets do (unlike a Buick Grand National).

If you take out enough timing and keep the engine fueled well you can run a turbo with the stock motor. I'm convinced (through personal experience and speaking with 10-15 or so other turbo owners) that eventually something will break. Therefore you might want to factor in a rebuild with forged pistons into your turbo budget. Another cheap alternative is to swap in the thicker .051" f-body head gasket and bring the compression ratio down to 9.6:1. You'll still be running with non-forged pistons which will crack if detonation occurs, but you'll be helping to prevent detonation.

Dan Kunesh
'96 DCM turbo
[email protected]
10 psi turbo kit, 355ci rebuild with 9.6:1 compression ratio and forged pistons, stock heads and cam, 42# injectors, 2.5" catback exhaust, Vigilante torque convertor, FLP level 4 tranny rebuild, and BFG KDWS tires.
 
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Discussion Starter · #9 ·
What gas did you run with 7-8psi? I've heard in California only 91? or 92? is available. Over here in NJ, 91 is the middle range, 93 and 94 are available too. 94 is not the kind of thing I'd want to run every day but 93 is definitely affordable. I could definitely swap in a thicker head gasket to drop the CR a little bit to help out. Also, on the aluminum headed Vette/Camaros, and aluminum headed motors in general, can't you run more CR without detonation due to the fact that aluminum heads have less thermal efficiency (or something like that?)?
 
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Discussion Starter · #11 ·
You guys don't seem to be very positive about forced induction on the LT1! Do you think I would be better off with a sick set of heads/mild cam/tb/intake/full exhaust/gears/torque converter/shift kit than a turbo to shoot for low 13's/high 12's?
 
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Discussion Starter · #12 ·
With a good mix of cam/intake/exhaust/gears/slicks/PCM/etc... You should have no problem with low 13's/high 12's in good weather. You could add a shot of nitrous for those moments when you want low 12's/ high 11's? You'll love it but your tranny won't. Take a look at this it lists mods and 1/4 times Karl Ellwein's page
It helps me in planning my mods.
Good luck,
 
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Discussion Starter · #13 ·
Choosing between forced induction and naturally aspirated can be tough. I can tell you that turbocharging is like a drug...the power gains are addicting, but it can leave you with alot of headaches. With a turbo your get insane amounts of low end torque (I pulled 500 lb-ft at 3600rpm at the rear wheels) and a stock idle. No rough or raised idle, no shaky motor. The car is docile around town, but the power is there on demand. Another benefit is that it makes the power with a stock redline and stock shift points. You don't have to rev a turbo motor to make the power, therefore the drivetrain tends to last a long time. The problem with turbocharging (or supercharging) is that you end up making a mistake (lean fuel, overadvanced timing, too much boost for the compression ratio, too low octane) and breaking the bottom end (usually a piston) of the motor.

If your tolerance for risk is low, you might want to consider the naturally aspirated route. Most guys do with great results. A properly done package should idle and run well. First, try to find someone with a setup that gives you what you're looking for and ask them about cost, driveability, noise, and problems. Getting the power gains may be tougher, but it has been done many times by many people. Either way its gonna cost big money to make big power.

Dan Kunesh
'96 DCM turbo
[email protected]
407rwhp/500rwtrq
 
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Discussion Starter · #14 ·
Oops...I should have said "You don't have to rev a turbo motor to make the power, therefore the valvetrain tends to last a long time."

The drivetrain will take a real beating either way!

Dan Kunesh
 
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Discussion Starter · #16 ·
The basic turbo technology kit. I added a compressor bypass valve, a boost gauge, and a fuel pressure gauge. All should be considered requirements in my opinion. The kit tends to be leaky so be prepared to do some welding.

The turbo is a Turbonetics 60-1 HiFi. I'm maxing the capabilities of this turbo. Also the kit includes a Turbonetics Deltagate wastegate which is also maxed out.

Extra fueling is supplied by larger 42# injectors, a larger f-body MAF meter, and some simple changes to the PCM program with LT1 Edit. These are not included in the kit. Instead they include a Carroll Superfueler supplemental fueling system which is more expensive and less reliable than the larger injectors. I've got mine for sale if you want it.

Other than that the kit really comes alive with a catback exhaust and a higher stall converter. I run 93-octane fuel which is what premium is around here (Chicago).

Dan Kunesh
'96 DCM turbo
 
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Discussion Starter · #17 ·
Sorry...old quarter mile time listed. That was before the catback exhaust, the Vigilante, and when I was running 7psi on the stock motor (I now run 10psi).

Dan Kunesh
 
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Discussion Starter · #18 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by DKunesh:
The basic turbo technology kit. I added a compressor bypass valve, a boost gauge, and a fuel pressure gauge. All should be considered requirements in my opinion. The kit tends to be leaky so be prepared to do some welding.

The turbo is a Turbonetics 60-1 HiFi. I'm maxing the capabilities of this turbo. Also the kit includes a Turbonetics Deltagate wastegate which is also maxed out.

Extra fueling is supplied by larger 42# injectors, a larger f-body MAF meter, and some simple changes to the PCM program with LT1 Edit. These are not included in the kit. Instead they include a Carroll Superfueler supplemental fueling system which is more expensive and less reliable than the larger injectors. I've got mine for sale if you want it.

Other than that the kit really comes alive with a catback exhaust and a higher stall converter. I run 93-octane fuel which is what premium is around here (Chicago).

Dan Kunesh
'96 DCM turbo
<HR></BLOCKQUOTE>

Is it possible maybe this kit has changed quite a bit since you got it? In looking at their web site it says it comes with a Turbonetics T04B not a 60-1. I'm not sure which is larger? It also says it comes with a bypass valve. I agree that a boost guage, along with fuel pressure and probably a stoich meter or EGT guage is necessary too. I also agree that larger injectors are better to run than additional injectors. Did you not have to setup a rising rate FPR? Another thing I was curious about would be dynoing with cats and without cats. I know that cats on a n/a vehicle don't tend to make a huge difference but I'd think on a turbo vehicle moreso than any other forced induction motor that it may make a significant difference. Are you running 10psi on 93 octane with no detonation? I do plan on running 3.42 or 3.73 gears, a vigilante TC with a high stall (3??? RPM?) and maybe not much else? Thanks for the info again. Basically step one for me is getting the minor little things fixed and then I'm onto the big power!
 
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Discussion Starter · #19 ·
They probably have changed the kit over the 2 1/2 years since I purchased the kit. Good to see they now include the bypass valve. They've also monkeyed with different turbo header designs as the original ones would crack welds. It happened to me and 9 of 10 other turbo owners I've talked to. I'm not sure of the difference between the T04B and the 60-1. I'll check my Turbonetics catalog and try to get you an answer. You might ask George at Turbo Tech his opinion on turbo choice.

Rising rate FPR is not required nor desired. The stock FPR increases pressure linearly with boost, i.e. 43 psi at 0 vacuum and 53 psi at 10 psi of boost. Rising rate FPR, I think, increase pressure at a higher rate than boost pressure. With the power levels I'm running the MAF meter is still in control and does a fine job of measuring air flow and the 42# injectors are very capable of providing enough fuel without increasing fuel pressure.

I run the high flow cats provided in the kit so I can't give a perspective on running without them. I do know that any exhaust restriction tends to choke a turbo motor. I picked up big power changing from stock exhaust to a 2.5" free-flow catback.

Yes I run 10 psi with 93 octane with 9.6:1 and forged pistons. I do get audible knock in third gear so I don't hit WOT in third gear anymore until I can get a boost controller to limit boost to 7psi in third gear.

Vigilante has a special stator for turbo motors. They recommend not much higher than 2,800 rpm stall speed given the very low torque band of a turbo'd stock motor. Turbos make big torque very early. And the stock motor doesn't rev very high anyway. For perspective, with the Vigilante I can light up the stock BFG tires anywhere in first gear by flooring the pedal. You'll want a set of drag tires. Only reason I haven't purchased a set is that I fear breaking the rearend and I'm plumb out of hobby money right now!

Dan Kunesh
'96 DCM turbo
 
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