1) WHAT COMPONENTS ARE REQUIRED TO UPGRADE TO LS SERIES GEN 3 PCM ON AN LT ENGINE?
2) WHAT YEARS OF LT1 ENGINE DOES TORQHEAD 24XLINK PRODUCTS SUPPORT?
3) WHAT GEN3 LS PCM DOES TORQHEAD USE?
4) WHAT ACCURACY FOR ENGINE POSITION DOES THE TORQHEAD MECHANICAL SIGNAL KIT PRODUCE?
5) CAN 24XLINK COMPONENTS SUPPORT HIGH RPM APPLICATIONS?
6) ARE AFTERMARKET HUB AND DAMPER SOLUTIONS (SUCH AS ATI RACING) SUPPORTED?
7) WHAT TIMING CHAINS CAN I RUN WITH 24XLINK COMPONENTS?
8) WHAT ABOUT TRANSMISSION COMPATIBILITY?
9) I WANT TO USE AN AFTERMARKET PCM FROM FAST, HOLLEY, BIG STUFF, ETC. CAN 24XLINK COMPONENTS HELP?
10) HOW THICK IS THE TORQHEAD SENSING UNIT THAT REPLACES THE OPTISPARK, WILL THERE BE INTERFERENCE ISSUES?
11) HOW RELIABLE IS THE EXTERNAL CRANKSHAFT RELUCTOR?
12) WHICH 24X CRANK SENSOR DOES TORQHEAD USE AND WHY?
13) HOW RELIABLE IS USING YOUR EXISTING LT1 HARNESS WITH THE NEW LS G3 PCM AND IGNITION SYSTEM?
14) WHY IS THIS CONVERSION SO POPULAR IN THE LT1 ENGINE COMMUNITY?
15) WHAT CAN I EXPECT FROM A CUSTOM BASE TUNE AND DO I NEED IT?
16) WHAT ABOUT EMISSIONS?
1) What components are required to upgrade to LS series Gen 3 PCM on an LT Engine?
Whether or not you purchase TorqHead products or buy/source your own components, the following list is what you need for your 24x LS G3 PCM and ignition system conversion:
Computer:
1) LS Series Gen 3 PCM. GM's PCM PN# 12200411 is the model of choice for performance and availability.
Mechanical Components (for engine position feedback to Gen 3 LS PCM):
2) 24x Crank reluctor and crank Sensor.
3) 1x Cam reluctor and camshaft sensor.
Wiring Components:
4) Necessary power engine/trans wiring changes to connect to the Gen 3 PCM. Your options here are to
a) buy the TH 24xLink 'Plug n Play' 12200411 PCM (Plugs into your existing LT Harness)
b) re-pin/re-wire your own harness
c) buy a complete new harness.
5) Additional wiring and connectors for new crank, cam and ignition coils must be wired in or buy our Torqhead C3 Harness
6) Coil harnesses for each bank of coils.
Hardware:
7) Eight LS series Ignition Coils.
8) Ignition coil brackets/mounts.
9) Spark plug wires @ proper length for your coil mounting solution.
Engine Tune:
10) A base or mail-order tune to start the engine. Once running, the PCM can and should be tuned via track or dyno methods to gain full benefit of LS PCM. The great benefit is that now you can take your car to any shop that tunes LS cars....and there are A LOT of those ;). Tuning access = full power potential.
Misc:
11) New water pump gaskets
TorqHead's 24xLink full 'Works' kit comes with all the components above, except for a specific engine tune (base generic tune for LT engine is supplied). This is a great kit containing all the necessary parts, brand new, and ready to install.
With TorqHead, you can also buy the individual components based on your requirements.
Notes:
94/95 Model years will require the addition of a new OBD2 dash mounted DLC connector.
Engine coolant will also be required as it is drained during install.
Computer:
1) LS Series Gen 3 PCM. GM's PCM PN# 12200411 is the model of choice for performance and availability.
Mechanical Components (for engine position feedback to Gen 3 LS PCM):
2) 24x Crank reluctor and crank Sensor.
3) 1x Cam reluctor and camshaft sensor.
Wiring Components:
4) Necessary power engine/trans wiring changes to connect to the Gen 3 PCM. Your options here are to
a) buy the TH 24xLink 'Plug n Play' 12200411 PCM (Plugs into your existing LT Harness)
b) re-pin/re-wire your own harness
c) buy a complete new harness.
5) Additional wiring and connectors for new crank, cam and ignition coils must be wired in or buy our Torqhead C3 Harness
6) Coil harnesses for each bank of coils.
Hardware:
7) Eight LS series Ignition Coils.
8) Ignition coil brackets/mounts.
9) Spark plug wires @ proper length for your coil mounting solution.
Engine Tune:
10) A base or mail-order tune to start the engine. Once running, the PCM can and should be tuned via track or dyno methods to gain full benefit of LS PCM. The great benefit is that now you can take your car to any shop that tunes LS cars....and there are A LOT of those ;). Tuning access = full power potential.
Misc:
11) New water pump gaskets
TorqHead's 24xLink full 'Works' kit comes with all the components above, except for a specific engine tune (base generic tune for LT engine is supplied). This is a great kit containing all the necessary parts, brand new, and ready to install.
With TorqHead, you can also buy the individual components based on your requirements.
Notes:
94/95 Model years will require the addition of a new OBD2 dash mounted DLC connector.
Engine coolant will also be required as it is drained during install.
2) What years of LTx engines does 24xLink components support?
The mechanical signal kit that generates the 24x crank and 1x camshaft signals can be installed on any year LTx engine that came with an Optispark (spline or pin drive). The ease and compatibility of install of these components is the same for all engine years. '92-'97 LT1's across all the platforms are supported.
The 24xLink 'Plug and Play' LS PCM is currently designed to work with 94-97 LTx engines only. The early 1992-1993 engine wiring was different in regards to PCM, PCM connectors and Injector firing strategy. We do not have kits, that contain LS PCM integration, for 1992/1993 F Body and Corvettes. Only our signal kits and coils/coil brackets are compatible with 93 F-Body or 92/93 Corvettes.
The 24xLink 'Plug and Play' LS PCM is currently designed to work with 94-97 LTx engines only. The early 1992-1993 engine wiring was different in regards to PCM, PCM connectors and Injector firing strategy. We do not have kits, that contain LS PCM integration, for 1992/1993 F Body and Corvettes. Only our signal kits and coils/coil brackets are compatible with 93 F-Body or 92/93 Corvettes.
3) What Gen III PCM does TorqHead use for 24xLink??
The 24x-Link PCM utilizes a GM 12200411 PCM. This is a very capable, reliable, and supported Gen 3 PCM that works with GM's 24x crank trigger system. We only use new/remanufactured PCM units and the modifications we make are performed to the highest standard of electronic practice, hardware, and care. TH also upgrades and improves the sealing ability of the LTx style PCM ports from what GM did with the original LTx PCM. Finally, we always 100% test each PCM on our test bench to make sure all inputs/ouputs are functioning within specification. We are pleased to provide warranty on this PCM and should it ever fail then simply send it back for a new one.
4) What accuracy of engine position does the mechanical reluctors provide?
The 24x-Link kit was specifically designed to ensure the crank and cam signals would be as accurate and clean as possible. The crank signal is +/- 1 degree of true cylinder position and the cam signal is synced appropriately to the crank signal within +/- 0.5 degrees. This accuracy is WELL within OEM specs and took many months of RND to achieve. Each kit is also tested prior to shipping to ensure function of all components and confirm accuracy and tolerances on our "engine simulator". This dramatically increases the performance of our reluctor solution and guarantees you will have success on your installation.
5) Can 24xLink components support high RPM applications?
The 24xLink 24x/1x signal generating components have been tested to RPM's exceeding normal LTx engine RPM ranges (10k+ rpm). It is important to design and test components to such high RPM's to ensure the signals are strong, precise, clean and accurate. TorqHead believes the 24xLink design will deliver leading performance due to choice of a quality dual track crank sensor and reluctor. TorqHead has proven that the components will exceed the rpm that the Gen 3 PCM is capable of supporting. So go ahead and spin it up!
6) Are aftermarket damper solutions (SUCH AS ATI) supported?
Yes, All aftermarket damper solutions can be supported. Currently we offer the ATI racing dampers as an option during the checkout process. All other aftermarket dampers can be supported. Please contact Torqhead in regards to your personal damper and we will be glad to help. Even if its custom, we can make it work.
7) What timing chains can I run with 24xLink components?
It's Simple. Whatever timing chains you could/can run with the existing LTx timing covers and components you can still use without issue. The 24xLink components do not affect 'behind timing cover' parts or geometry of the LTx engines. 24xLink components are not affected by manufacturer variability in timing chain dimensions due to the use of an adjustable crank sensor mount. 24xLink can adjust to whatever components you want to use. Also in some instances the stock, 1996-1997 LTx, 4x crank reluctor can cause interference issues with certain timing chain setups. If you so desire you can remove this 4x reluctor from behind the timing cover. A reluctor of any kind is not required behind the timing cover when converting to 24xLink components.
8) What about transmission compatibility?
As of July 2016 our LS Gen 3 PCM can now control 1994 and 1995 transmissions. These transmission are controlled by the PCM exactly how they expect to be controlled and the hardware of the transmission stays "year correct" allowing for complete reliability. This new compatibility developed by Torqhead allows you to save time and money when upgrading to LS G3 PCM and ignition system on your 94/95 LT1 auto car.
All 1996+ transmissions are compatible with the LS G3 PCM from factory.
All 1996+ transmissions are compatible with the LS G3 PCM from factory.
9) I want to use an aftermarket PCM such as Fast, Holley, Big Stuff, etc.....Can 24xLink help?
The 24xLink crank and cam signal unit can definitely help! Aftermarket ECU's will require your engine to generate the 24x crank and 1x camshaft signals. By using the 24xLink signal kit you will be able to add these signals to your engine with bolt-on ease. To complete the installation of these aftermarket ECU's you will need to make the necessary wiring changes yourself using aftermarket ECU documentation and instructions.
10) How thick is the torqhead sensing unit, will there be interference with other components?
The 24xLink sensing unit is only a sliver thicker than a traditional Optispark distributor. This was an intentional design goal so that the design could fit and work with almost any already produced LT engine components on the front of the engine. So if you optispark fits, then the Torqhead sensing unit will fit as well. It is that simple.
11) How reliable is the external crankshaft reluctor?
We have dedicated countless hours of development and testing to ensure the external crankshaft reluctor delivers outstanding performance with uncompromising 'out of the box' reliability. Our design delivers a strong and rigid mounting strategy of the crankshaft reluctor and crankshaft sensor. The adjustment available for the crank sensor allows for ideal positioning and tolerance of the crank sensor in relation to the 24x reluctor. These design goals ensure a clean and 100% reliable crankshaft signal is generated regardless of RPM, or chosen engine components from manufacturer to manufacturer.
The 24x sensor reads the crank reluctor based on the principles of magnetics and is inherently unaffected by the environmental dirt, water or debris. Finally the centrifugal forces generated by the spinning reluctor keep it clean no matter where you operate the vehicle. Everything just flings right off. Nearly all the major car manufacturers and aftermarket EFI system manufacturers have implemented similar crankshaft position designs on road/racing vehicles for decades and all these vehicles have operated for many 100,000+ reliable miles.
Quality sensors and attention to tolerances (both delivered by our design), far outweighs other solutions when it comes to adding crankshaft positioning to an engine not originally equipped with such sensors or reluctors.
The 24x sensor reads the crank reluctor based on the principles of magnetics and is inherently unaffected by the environmental dirt, water or debris. Finally the centrifugal forces generated by the spinning reluctor keep it clean no matter where you operate the vehicle. Everything just flings right off. Nearly all the major car manufacturers and aftermarket EFI system manufacturers have implemented similar crankshaft position designs on road/racing vehicles for decades and all these vehicles have operated for many 100,000+ reliable miles.
Quality sensors and attention to tolerances (both delivered by our design), far outweighs other solutions when it comes to adding crankshaft positioning to an engine not originally equipped with such sensors or reluctors.
12) Which 24x crank sensor does Torqhead use and Why?
Paramount to any high performance engine management system is for the computer to know accurate and reliable engine position (the location of all the pistons in their stroke and angular velocity of the crankshaft). The computer relies completely on the crankshaft position (CKP) sensor for accurate crank position readings from the crank mounted reluctor (such as a 24x reluctor). The quality level of the CKP sensor's internal circuitry can not be overstated and for this reason Torqhead has chosen to utilize a purpose built 24x GM crankshaft position sensor that delivers outstanding performance, GM PN 10456248. While this crank sensor is not cheap (in fact it is about the most expensive sensor you can buy for this application), it is the only true 24x dual track crank sensor that meets our stringent design requirements and has always passed our testing protocols. We have tried cheaper alternatives that result in failure. Put quality first!!
13) How reliable is using your existing LT1 engine harness with the TH LS G3 PCM and ignition system?
The old adage "If it isn't broke, then don't fix it" applies very well here. However more than that old adage can instill, we have also installed 200+ 24xLink conversions at the time of this writing. In all those conversions not a single installation has had issues because an original LT harness is being used. The cars simply fire up and work, just as if the LS PCM had been connected since day one. Unplugging the four PCM connectors and plugging them into our TH LS PCM is the full extent in which you need to touch the original LT engine harness. No fuss, no muss. You wouldn't replace your engine harness when disconnecting and reconnecting the stock LT PCM would you? A harness should be replaced only when it is so badly damaged that it can no longer be fixed, not because you plug in a new PCM.
Needing to replace the LT1 engine harness when installing a LS PCM is simply NOT TRUE and our Torqhead Plug n' Play LS PCM (as well as the many others who perform their own DIY LT harness re-pin) conversions have the track record to prove it. What is true....and what our plug and play PCM ensures without fail....is that when doing this conversion all the right connections (from/to) need to be made from every electrical component to the PCM. The right terminal at the right pin location is a must and failure to do so is usually the reason a DIY harness re-pinning can be hit or miss (miss = going back over nearly 100 wires again).
The additional wiring needed, for the new electrical components (24x Crank sensor, 1x Camshaft sensor and Coils), is all brand new supplied with our kits in the form of or C3 Add-On harness. This add-on harness comes configured for F, B or Y-Body form respectively.
We acknowledge that if your existing harness is visually damaged, burned, or has been torn off and on the engine many many times then it is suggested that you investigate & fix the damaged wires or if absolutely necessary replace the harness with a good used LT harness (great value and commonly available from many reputable shops) before upgrading.
If everything is working with your existing harness, then "If it isn't broke, don't fix it". The end result is a perfectly running engine from a Plug n Play PCM swap, an original LT engine harness and a small additional lay-in harness (TH C3 Harness).
We KNOW that your factory harness will work and deliver the performance you expect for many years to come! Just ask the 100's of LT1 cars running our kits. :)
Needing to replace the LT1 engine harness when installing a LS PCM is simply NOT TRUE and our Torqhead Plug n' Play LS PCM (as well as the many others who perform their own DIY LT harness re-pin) conversions have the track record to prove it. What is true....and what our plug and play PCM ensures without fail....is that when doing this conversion all the right connections (from/to) need to be made from every electrical component to the PCM. The right terminal at the right pin location is a must and failure to do so is usually the reason a DIY harness re-pinning can be hit or miss (miss = going back over nearly 100 wires again).
The additional wiring needed, for the new electrical components (24x Crank sensor, 1x Camshaft sensor and Coils), is all brand new supplied with our kits in the form of or C3 Add-On harness. This add-on harness comes configured for F, B or Y-Body form respectively.
We acknowledge that if your existing harness is visually damaged, burned, or has been torn off and on the engine many many times then it is suggested that you investigate & fix the damaged wires or if absolutely necessary replace the harness with a good used LT harness (great value and commonly available from many reputable shops) before upgrading.
If everything is working with your existing harness, then "If it isn't broke, don't fix it". The end result is a perfectly running engine from a Plug n Play PCM swap, an original LT engine harness and a small additional lay-in harness (TH C3 Harness).
We KNOW that your factory harness will work and deliver the performance you expect for many years to come! Just ask the 100's of LT1 cars running our kits. :)
14) Why is the conversion to a Gen III LS PCM so popular in the LT1 Community? What can it mean for me?
We talk to dozens of enthusiastic and passionate LT1 owners every day. The story is nearly always the same in that they are modifying or building a LT1 setup and they no longer can count on the Optispark for the reliability they need. They also desire superior diagnostics and tuning support so that they can control/tune the engine to get full performance. They search their local area (even 100's of miles away) for dyno tuning facilities to unlock the full potential of the engine and they quickly realize there are no shops that are willing or can tune their old LT1 PCM. It is unfortunate, but not having LT1 tuning access, is the case for the vast majority of LT1 owners. Without a great tune, how are you supposed to unleash the full potential that your modifications or new build are designed to deliver at the Track? The answer.....Get your hands on a common and high performance PCM engine management solution that is widely tuned at nearly every dyno shop in the USA/Canada/Worldwide. The 24x Gen 3 PCM meets this requirement and is a very capable PCM for even very high HP builds. It can deliver the tuning access you require and also run your LT1 better than the factory PCM. With tuning access and a reliable spark delivery system you can unleash the full potential of your engine build/modifications. This ensures the money you spend on the hard parts is enhanced by the electronics/tune.
15) What can I expect from a custom base tune and do I need it?
When choosing to upgrade to a LS PCM and ignition system on your LT1 there are is an initial requirement of a tune that will get the engine up and running after installation. It is important for a customer to verify 'installation success'; that the engine systems and engine as a whole is operational. The engine may not be running great, but it is operational and additional tuning is usually always recommended and required to really dial in performance.
The Tune options from Torqhead:
Torqhead has developed a factory-spec LT1 base tune that is always included in any kit that contains our plug and play LS PCM. If your engine is close to factory spec, and perhaps has 30# or less injectors this factory tune will serve quite well before moving on to more on-car tuning locally. If your engine is highly modified then the requirement for a custom base tune, that is close to what your specific engine requires, becomes increasingly important for startup success. Torqhead offers a custom base tune service for $135 additional charge on any kit that contains our plug and play PCM. The custom base tune meets the requirements of getting your engine up and running, installation verification and allows confidence to then move onto additional tuning on your car at a local dyno tuner or track tuning. How well will the custom base tune run your engine? This depends on each car and engine build. The more modified, the less likely a mail order base tune like this is going to deliver great performance from idle to wide open throttle out of the box. There are just to many variables to consider that only a dyno tuning session can truly deliver. The main goal of the custom base tune is engine operation, installation verification and the ability to lightly operate the car for additional tuning needs. If the tune runs the car quite well, that's great! However always know that additional tuning locally via track or dyno will really bring the performance up to where it should be.
The Tune options from Torqhead:
Torqhead has developed a factory-spec LT1 base tune that is always included in any kit that contains our plug and play LS PCM. If your engine is close to factory spec, and perhaps has 30# or less injectors this factory tune will serve quite well before moving on to more on-car tuning locally. If your engine is highly modified then the requirement for a custom base tune, that is close to what your specific engine requires, becomes increasingly important for startup success. Torqhead offers a custom base tune service for $135 additional charge on any kit that contains our plug and play PCM. The custom base tune meets the requirements of getting your engine up and running, installation verification and allows confidence to then move onto additional tuning on your car at a local dyno tuner or track tuning. How well will the custom base tune run your engine? This depends on each car and engine build. The more modified, the less likely a mail order base tune like this is going to deliver great performance from idle to wide open throttle out of the box. There are just to many variables to consider that only a dyno tuning session can truly deliver. The main goal of the custom base tune is engine operation, installation verification and the ability to lightly operate the car for additional tuning needs. If the tune runs the car quite well, that's great! However always know that additional tuning locally via track or dyno will really bring the performance up to where it should be.
16) What about Emissions?
Our LS PCM conversion kits are legal for sale and use on LT1/LT4 swapped Uncontrolled (Non-Emissions Controlled) Vehicles and Racing Use Only Vehicles.
The following vehicles are considered Uncontrolled (Non-Emissions Controlled) Vehicles:
The following vehicles are considered Uncontrolled (Non-Emissions Controlled) Vehicles:
- 1965 and older U.S. manufactured California Certified vehicles
- 1967 and older U.S. manufactured Federally Certified vehicles
- 1967 and older Foreign manufactured vehicle
- Racing Use Only Vehicles are vehicles that are used exclusively for competition and that are not registered and that may never be used on the street