Hello, new member here. I've got a 2004 with 208k on it and it needs some minor things, so I thought I'd do a few upgrades at the same time. I have a tsp stage 2 low lift 212,218 .500 .500 cam and I'm wanting to get the prc ported heads with the bigger valves. I'm contemplating a tbss intake. Some say they've lost bottom end power because of the smaller displacement. I have 706 heads and I'm wondering if the extra flow from the cam and heads would be enough to prevent a loss and make the swap worthwhile?
thanks.

 

Are you new to engines in general? What you want to do will reduce low end power even more. The TBSS intake won't hurt, but if you go with the heads, you should get an even looser converter than the one you have. Forced induction is the only way to boost power across the RPM range, any N/A mods always compromise some part of the power band.

 

milling the heads will help you gain compression which will help you with low-end, the nnbs intake will hurt slightly but it wont be too bad. getting the heads ported and milled would be better than just getting them ported.

 

Not at all new to engines, just trying to get a second opinion on some conflicting information. When I called tsp and told them I wanted to keep the stock converter and also didn't want to lose much down low, they recommended this cam. The dyno graph compared to the stock cam is about even at 2000 rpm with stock heads. A lot of guys say they don't feel the loss down low and it adds a lot of mid range torque. Others make it sound as if it's a dog down low compared to the stock cam. They did also say they would match the milling of the heads to cam.

 

I was thinking about bumping up the compression to get some more low end torque too. What doesn't make sense is I read somewhere that the nnbs 4.8 had the better intake manifold, higher flow heads and roughly 8.8 compression, yet put out more HP than the nbs 4.8. That would lead me to think that the higher flow isn't killing the low end too much if they improved the breathing from the factory and lowered the compression. Is there something other difference on the nnbs 4.8/5.3?

 

from experience when i had the 5.3 with a 212/218 cam and ported 799 heads milled .030 it did lose lowend i could feel it, after 3k rpm it would finally come alive.
ive seen a article where the 706 heads make better power than the 799 , 243 heads on the 4.8 5.3 engines

i added the same cam and the heads to the 6.0 and it was a day and night difference.

im sure youll be ok porting those heads and have them milled. gears will help you get away with not needing a converter not sure which ones you have right now