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is it worth it with the mods i have to install a LT4 KM
also is it better to have a dyno tune or a pcmforless tune?
I asked bryan herter about this when i got my pcm tuned and he told me that he desensitizes the stock KM and with your mods, similar to mine, you will probably not get any knocks after a pcmforless tune. I ran my car with datamaster and never picked up a single knock.

pcmforless tune is cheapest and good, obviously a real dyno tune is better but more expensive, or if possible, you could get a dyno tune from pcmforless!
 

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is it worth it with the mods i have to install a LT4 KM
also is it better to have a dyno tune or a pcmforless tune?
Yes. A LT4 KM is ALWAYS worth it!!! (Any mod/power level)

IMHO, of course... ;)

Yes, it is ALWAYS better to have a dyno tune, versus a 'mail-order' tune... (**IF, and ONLY IF, your 'tuner' KNOWS what they're doing!!!)

On that note, get a PCMFORLESS tune!!! ;)

The best of the best!!!

:)
 

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is it worth it with the mods i have to install a LT4 KM
The LT4 KM was needed because the noise of the roller rockers used in the LT4 was causing some false knock retard. With stock rockers you'll likely see no benefit.

also is it better to have a dyno tune or a pcmforless tune?
A dyno tune by Bryan would be an even better option.
 

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A dyno tune is always the best, but hardly necessary for bolt on mods. Any good programmer will be very familiar with the standard bolt-ons. Any major changes, like ported heads, forced induction, etc which normally varies from set-up to set-up will be almost manadatory for a dyno-tune.

The LT4KM has it's own risks unless it's needed. Roller rockers, a cam, and headers are usually things that could set off false knock with the stock KM. If you don't have those mods, then an LT4KM could miss true knock (be overly desenitized). I'ver heard this is even more the case with OBD1.
 

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sorry for my ignorance but im thinking your talking about the lt4 knock module.....like 9 yrs ago i did the whole gm hot lt4 kit and i cant remember if i changed this piece- where or what can i check to see if ive already done this?

thanks in advance everybody
 

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There is absolutely no benefit to LT4 KM unless you have knock retard. Get a scanner or a laptop with Datamaster instead and scan your PCM.

Also, LT4 KM is known to over-desensitize OBD-1 PCMs because it was designed to filter out specific knock range in OBD-2 (96) corvettes with aluminum heads and aluminum roller rockers. The frequency can be different with iron heads and/or steel rockers. You can desensitize PCM to knock or make it recover quickly as a part of the PCM tune without spending money on the module.
 

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sorry for my ignorance but im thinking your talking about the lt4 knock module.....like 9 yrs ago i did the whole gm hot lt4 kit and i cant remember if i changed this piece- where or what can i check to see if ive already done this?

thanks in advance everybody
Its in the pcm under the access door. It looks identical to the stock lt1 KM except the first set of numbers on top of it should be 16214681, if its the lt4 KM.
 
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