Upgrading manifolds - is it necessary to upgrade to a bigger TB
 

I've been looking more seriously at upgrading my manifolds lately, and my question is of the necessity of upgrading to a larger TB (62mm), taking into account the fact that I do not plan on purchasing HP tuners at the moment and would prefer to be able to still use my car without a retune (if possible).

Would I need a retune anyway after upgrading the manis?

How significant would the TB upgrade be on a bone stocker except the hypothetical mani upgrades? Because I can see $250 being spent elsewhere.

Headers are in the budget somewhere down the road.. but the question comes to mind because the upper manifold, as sold by WOT-Tech, can be ported to accommodate the larger TB. I wouldn't want to have to send my UIM in again later to have it ported to fit my larger TB.

If you are going to do the mani's you might as well do the TB too. You're only going to let in as much air as the TB will allow and if the port is smaller than that on the mani.....

Also a tune is not really necessary. It would probably help, but not too much. I ran a stock PCM for a few years before going to a upgraded PCM and I don't think the PCM I have now has anything for P&P mani's anyway ;)

Your car will idle higher when you start it up on a cold day

Ok, thank you Redog :)

One more question - how significant would the the gains be with a WOT-Tech mani upgrade (incl. the 62mm TB)? I know it's hard to ask this question but I think someone else has upgraded in a similar fashion and could lend some insight? If it's not too significant, I might just keep saving toward the big S/C setup, but the manis/TB seem like a relatively inexpensive boost, if I'm reading into it properly.

I have the RSM pair. It helped a little bit, but don't expect too much out of it unless you have other mods too.

It's a good first mod, and the ones that are over on wot-tech.com are better than the ones I have in my car. I'm upgrading to WOT tech's mani's soon. I have them, but just have to find the time to do the swap ;)

Ahh ok. I saw someone else on the board swear by the gains offered from ported manis and headers so who knows!

Haha ok! But since you mentioned it... how difficult is the swap? Something best left to a mechanic for a novice such as myself? Most I've done is a CAI install and an ECT replacement lol. Haven't worked on the engine yet, and if it entails the same thing(s) as an LIMG replacement, I might want to stay away from this one? :lol:

From what I understand, swapping out the manifolds would basically be the same as the LIMG replacement, seen here: http://www.gaownersclub.com/forum/sh...nifold+install

Is this correct? Just laying a new manifold in place after putting in the new gaskets rather than putting the old ones back on?

Yes doing both manifolds is the same job as the LIMG.

You'll see some increase, but this mod is supported better by other mods. Headers are a good addition to this, but doesn't have to be done rigth away.

I'd say save up for the TB also and get it all at once, trust me, you'll be a lot happier.

Also, make sure that you get either a 00 or 03 lower manifold, these flow better stock than a 99 manifold ported. I currectly have a 99 manifold. I have a 00 P&P manifold, powdercoated and ready to go in, but I'm going to wait until it has to be done, and just because you have to pull out the pushrods to install the new gaskets, I'm not going lower than the upper manifold which I am replacing soon

Thanks for all of the info, Red. After much debate, I think I'll be doing headers before manifolds.