TorqueHead vs Opti

[Lenny5160]

Originally Posted by Billy Nees

Oh, the "clarification" issue isn't just on Dan. The person in charge in Glendale made a correction/clarification without researching it.
Are you familiar with the 1992-1997-8 LT-1? It has no distributor! It has no place to put a distributor! It is unlike any other conventional small-block Chevy. The spark and fuel are controlled by a "crank" position and a cam position sensor through the ECM.

I'm not, but in this case it clearly sounds like a distributorless ignition system, so those currently running a crank trigger should feel pretty comfortable instead of raging at Dan to 'fix this'.

[Billy Nees]

Dan should stop sowing the seeds of confusion. Nothing needed to be "fixed".

[Doug Hoven]

Originally Posted by Billy Nees

Oh, the "clarification" issue isn't just on Dan. The person in charge in Glendale made a correction/clarification without researching it.
Are you familiar with the 1992-1997-8 LT-1? It has no distributor! It has no place to put a distributor! It is unlike any other conventional small-block Chevy. The spark and fuel are controlled by a "crank" position and a cam position sensor through the ECM.

Interestingly enough, in GM F-body shop manuals, they actuall refer to the optispark unit as the "disributor ignition system."(see attatched) I don't believe one could quite classify it as a "crank trigger" looking at the way it works. Correct me if I'm wrong(being that I am primarily a FFFord guy), behind the cap there is a rotor that uses slots on a gear with an optical sensor to determine when a spark should be administered. This sounds to me to be more similar to a "hall effect" type distributor used in 80s fords and chryslers rather than a traditional "crank trigger." IMHO the rule should be written to include all fuel injected stockers in determining if crank triggers are allowed in stock or not.

[SSDiv6]

When the LT-1 engines and other EFI engine makes were introduced into drag racing, Jim Skelly was the guy that approved the use of aftermarket EFI ECU's and also approved the use of the crank trigger systems on engines that have a crankshaft position sensor in lieu of a single distributor that handles the ignition duties. The current language that everyone has used throughout the years was written by Jim and has not changed.

This same issue has taken place with other engine makes of ignition systems that have been previously approved by NHRA and later on deemed to be illegal only to be rescinded when NHRA found the original acceptance.

Below is a depiction of the OEM crankshaft sensor position on the LT-1 engine and Jim did not see an issue allowing the use of a crank trigger system in lieu of the OEM sensor because they both perform the same function.

[kdanner]

Originally Posted by Doug Hoven

Interestingly enough, in GM F-body shop manuals, they actuall refer to the optispark unit as the "disributor ignition system."(see attatched) I don't believe one could quite classify it as a "crank trigger" looking at the way it works. Correct me if I'm wrong(being that I am primarily a FFFord guy), behind the cap there is a rotor that uses slots on a gear with an optical sensor to determine when a spark should be administered. This sounds to me to be more similar to a "hall effect" type distributor used in 80s fords and chryslers rather than a traditional "crank trigger." IMHO the rule should be written to include all fuel injected stockers in determining if crank triggers are allowed in stock or not.

Yep. Someone should not have poked the bear!

[KRatcliff]

Originally Posted by Doug Hoven

Interestingly enough, in GM F-body shop manuals, they actuall refer to the optispark unit as the "disributor ignition system."(see attatched) I don't believe one could quite classify it as a "crank trigger" looking at the way it works. Correct me if I'm wrong(being that I am primarily a FFFord guy), behind the cap there is a rotor that uses slots on a gear with an optical sensor to determine when a spark should be administered. This sounds to me to be more similar to a "hall effect" type distributor used in 80s fords and chryslers rather than a traditional "crank trigger." IMHO the rule should be written to include all fuel injected stockers in determining if crank triggers are allowed in stock or not.

The Optispark is considered a front mounted distributor, but a stock LT1 from GM comes with both a crank sensor and a cam sensor. Thus my comment when I quoted the rule book that an LT1 should be allowed to run a crank trigger since it comes with one from the factory.

The rule book is a bit out dated, but how can you not allow a car in the guide to run the same equipment as it came from the factory? Would tech bounce a purely stock LT1 because it has a crank sensor?

[SSDiv6]

Originally Posted by KRatcliff

The Optispark is considered a front mounted distributor, but a stock LT1 from GM comes with both a crank sensor and a cam sensor. Thus my comment when I quoted the rule book that an LT1 should be allowed to run a crank trigger since it comes with one from the factory.

The rule book is a bit out dated, but how can you not allow a car in the guide to run the same equipment as it came from the factory? Would tech bounce a purely stock LT1 because it has a crank sensor?

Kyle,

It was the premise used by Jim Skelly to allow the use of crank trigger systems on the LT-1 and other EFI engines, based that the cam and crankshaft sensor are separate functions from the cap and rotor that all they do is distribute the electrical current to each spark.

The same situation I went through with Pat on the Cobra Jet 429 Ninja when he told me I could not use Coil-On-Plug (COP) because it was based on a Windsor engine.

Well, Ford Racing had gotten approval to use either a distributor or COP ignition and it had been approved by NHRA and was told by the Indy Office it was legal to run COP.

By the way...Happy Birthday Kyle (Mr. Sheep Husbandry Expert...)

[KRatcliff]

Hahahaha! Thanks bud.

[Doug Hoven]

Originally Posted by KRatcliff

The Optispark is considered a front mounted distributor, but a stock LT1 from GM comes with both a crank sensor and a cam sensor. Thus my comment when I quoted the rule book that an LT1 should be allowed to run a crank trigger since it comes with one from the factory.

The rule book is a bit out dated, but how can you not allow a car in the guide to run the same equipment as it came from the factory? Would tech bounce a purely stock LT1 because it has a crank sensor?

I do understand the argument that you could consider a crank trigger as being some sort of crank position sensor. The issue is that the crank sensor was not used to fire the ignition in Lt1 cars. Lt1's weren't actually fitted with a crank sensor until 1996. The computer still is only using the camshaft position, determined by the optical sensor behind the distributor cap, to fire both the spark and injectors. The crankshaft position was actually fitted to detect any misfires by using crankshaft speed and position to determine if there is a slight drop in crank speed at a certain interval.

[Adger Smith]

When did Pat become the National Tech director?
Sometimes it takes a long hard look at the wording and punctuation of the rule &
understanding the function of the factory systems
I would to go to the top to get the correct/final answer