litle88

iTrader: (20)

My brother has an 07 5.3 flexfuel Tahoe and wants to start modding it.
Do they actually have 243 heads?
If so are they sodium filled valves?
If he cams it would he have to change pushrods if he went with a HOTCAM?

Is Tuning available with E85 fuel?

I tried a search but if anyone has links to threads please send them my way, I am curious about these 07 5.3's
THANKS

jakebdb56

iTrader: (24)

they do have the 243's, but not positive on the sodium filled exhaust valve. There definitely is tuning available with E85. I can't remember exactly what Mike told me, but I think he mentioned something about being able to get more timing with ethanol? iono
The pushrods are just extra insurance from what I've been told. I have a hotcam that I plan on installing soon. IMO when GMPP sells the hot cam kit it only comes with the cam and ls6 springs. If it really needed pushrods I think the kit would come with some. I'm not relying on that as my source for not getting pushrods. I've asked a few board members and even LPE about the pushrods question.

litle88

iTrader: (20)

thanks Jake, what I meant was the pushrod length, since the valves on the intake side are a little longer?

litle88

iTrader: (20)

Also how big are the injectors?
Come on guyz, at least point me in the right direction.

jakebdb56

iTrader: (24)

not sure, but I don't think that valve length will matter in pushrod length. The 7.4's are the stock length still for that block/head setup. I'm going to reuse the stock rods. Maybe I'll get 7.4's if I do nitrous or something. It's really easy to swap pushrods, but springs are a bitch (mostly time consuming).

litle88

iTrader: (20)

Anyone?

Jake I would just get that little extra insurance buddie, and spend 80 bux and not worry about a bent Rod!