MSD ignition 99tahoe...?

[Lokix27x]

Hey guys, I have a 99 tahoe 5.7 vortec 4x4, I've been given a MSD ignition 6al by a buddy of mine, was thinking about installing but I have a few questions... would I need to run 93 octane fuel after installing? Would I improve gas mileage at all? What would the hp/torque gains be? Would it be beneficial, or should I just leave it be and save it for a project?
On another note, anyone know of a good stainless set of long tube headers for it? (Keep in mind it's 4x4)
Thanks guys, any advice is greatly appreciated.

 

[SunlitComet]

no increase in octane with just the 6al unit. improvements are there but lower then say a exhaust modification but the are there slightly. it is still worth using especially with the other components added on as well it does do a better job of ignition burning the fuel. for long tubes you may need to check legality and with those you will likely need to modify the exhaust in that area to get them to fit properly. you will also need ones that have a egr pipe connection and maybe even an a.i.r connection depending on how your emissions are configured.

 

[SunlitComet]

i should add that shorties or mid lengths are better if this is used for anything other then racing.

 

[BlkYukon]

I wouldn't bother with an MSD box. They like to puke, don't offer any performance improvement on a stock truck, I stick with Delco ignition components

 

[jerryjoe28]

any plans for other supporting mods?

 

[Lokix27x]

Ok. I have the 6al, planned on getting the msd coil and wires when I did install, and eventually plan on getting a tuner and k&n induction, any suggestions on the tuner? If I ever have to do intake gaskets I plan on upgrading spider as well. How about throttle body spacer? Any other mods/upgrades that any of you suggest that will show gains in hp and mpg will be greatly appreciated. Thanks fellas.

 

[Lokix27x]

Only wanted long tube because they look badass lol

 

[SunlitComet]

blackbear is a common tuner used by others here. would not bother with a tb spacer especially if doing kn intake. there is cat-back systems. electric fans. rocker arm upgrades for just power.

 

[Lokix27x]

And also, I plan on moving to the country in the next year or so, emissions are not needed there in my state. So I'll probably end up running free flowing exhaust. Also my reason for wanting long tubes, hopefully equal length, to help the motor exhale more efficiently. May run a DI/DO muffler with built in crossover, mainly just for noise pollution when I travel to the city to see my dad...

 

[Lokix27x]

Oh yeah! Thanks for the reminder. Convert my fan as well.

 

[Lokix27x]

Don't plan on messing with the valvetrain until noises are heard lol. But I'll keep that in mind.

 

[SunlitComet]

if you remove the cats performance will become an issue. if living in the country with terrain i would get shorties or mids to retain or improve torque output

 

[SunlitComet]

btw rockers are easy really. if you did hear noise in the valvetrain in a vortec trust me you will have more then just valvetrain issues.

 

[Lokix27x]

Which rocked are you recommending? I know they're not hard btw. Just didn't feel like messing with em, but I'll look into them if they will help with gains. Will they increase hp/tq output?

 

[Lokix27x]

Rockers***

 

[Big Poppa Pump]

btw rockers are easy really. if you did hear noise in the valvetrain in a vortec trust me you will have more then just valvetrain issues.

Do you also have a write up for the job?

 

[SunlitComet]

1.52 are the simplest to put in with out modding the head pushrod holes and will give a slight increase 1.6 requires a pushrod hole *********** on the head. i use comp cams 1.52 magnum rollers right now. the vortec's use a 3/8" stud with self adjusting rockers and hardware. for more info read this and this.

predure to set them up is below.

 

[Lokix27x]

1.52 are the simplest to put in with out modding the head pushrod holes and will give a slight increase 1.6 requires a pushrod hole *********** on the head. i use comp cams 1.52 magnum rollers right now. the vortec's use a 3/8" stud with self adjusting rockers and hardware. for more info read this and this.

predure to set them up is below.

Did you upgrade cam? If so, which would go best with upgraded rockers? While I'm at it, what else should be upgraded...? If I went with bigger rockers, I assume heads would have to come off and sent to machine shop for ***********, or could I do that myself?

 

[jerryjoe28]

Ok. I have the 6al, planned on getting the msd coil and wires when I did install, and eventually plan on getting a tuner and k&n induction, any suggestions on the tuner? If I ever have to do intake gaskets I plan on upgrading spider as well. How about throttle body spacer? Any other mods/upgrades that any of you suggest that will show gains in hp and mpg will be greatly appreciated. Thanks fellas.

I have a black bear tune and would recommend them

Did you upgrade cam? If so, which would go best with upgraded rockers? While I'm at it, what else should be upgraded...? If I went with bigger rockers, I assume heads would have to come off and sent to machine shop for ***********, or could I do that myself?

if u have never done that then yes you will need to send them off

 

[SunlitComet]

no cam upgrade and as i said before the 1.52 require no supporting mods.