2005 corvette ls2 gen 3 or gen 4????

[Wakethis2006]

So doing some tuning on my corvette and wondering. is this considered a gen 3 or gen 4 setup? i know its a 24x but alot of things on the ecm are gen 4 but some are gen 3 when going off using the tuning school. so just curious what peoples opinion's are.

[blindsquirrel]

HPT and the forum consider the E40 as a Gen4.

Click 'Tune Details':

Hardware E40, ECM, GM Gen4 V8

[Dave_In_VA]

So doing some tuning on my corvette and wondering. is this considered a gen 3 or gen 4 setup? i know its a 24x but alot of things on the ecm are gen 4 but some are gen 3 when going off using the tuning school. so just curious what peoples opinion's are.

The 2005 Corvette is a Gen 4 corvette but it has a one year only ECM - the E40.

I know because I am tuning my built 05 corvette and have spent a crap load of time on this issue.

In 2006 the E38 ECM was released with the corvette.

There are several big differences between a E38 and an E40, including the e40 has VVM tables while the E40 has VE and MAF Low and High tables similar to a Gen 3. However, the E40 allows decimals in the VE table while the Gen 3 does not. This makes SD tuning more precise.

This is a picture of an E38 VVE table:

2022-05-15.jpg

And this is a picture of an E40 VE and MAF tables

2022-05-15 (1).jpg

There are more variables in across the spectrum of option in the engine tab. Attached is a stock 09 corvette manual tune file you can use to compare. Open both separately, don't use the compare function as HP will only show common attributes.

Also, the 05 corvette has a very weak rear-end (i.e. differential).

Attached is a stock


/df

[Wakethis2006]

already upgraded rear end and thank you for the response. currently fighting a reduced engine power issue on mine. turn the key on and get reduced engine power. no codes tho and sometimes will start and sometimes wont and once it does start and reduced engine power kicks on then it just shuts off again. guessing i have a electrical gremlin somewhere. the car sat for a few years till i had time to put the motor back in but i feel the issue may be a tpms issue as i didnt have issues till i was gonna drive it to log alittle and aired the tires up and now once sensor shows 0 and im getting that reduced engine power. putting new tpms in tomorrow so will see. ive seen mixed reviews that it can cause an issue.

[blindsquirrel]

Check that none of the important DTCs got turned off somewhere in the past, a throttle condition that makes it not start (that's an intended behavior for some ETC faults) should definitely be setting a code.

[peter logan]

There are several big differences between a E38 and an E40, including the e40 has VVM tables while the E40 has VE and MAF Low and High tables similar to a Gen 3. However, the E40 allows decimals in the VE table while the Gen 3 does not. This makes SD tuning more precise.

/df

what gen3 pcm doesn't have decimals ? all my tune files do