Intake manifold

[BLK60SS]

I posted this over at another forum but that forum just doesn't move like this one does. Here's what I posted:

Quick question. I remember reading somewhere that there was a reason why GM changed the intake manifold on the TBSS but I can't remember what it was. I personally think the current manifold looks like ass and would have been so much better with the C6 LS2 intake manifold. Question is, what performance gain/loss would an intake swap of this sort net? Also, is the TBSS's TB 90mm?

[Chotton]

It was a packaging issue. The C6 LS2 intake will not fit. Net loss was 5 horsepower.

[BLK60SS]

It wouldn't fit in the back by the firewall right?

[SlvrTBSS]

I posted this over at another forum but that forum just doesn't move like this one does. Here's what I posted:

Quick question. I remember reading somewhere that there was a reason why GM changed the intake manifold on the TBSS but I can't remember what it was. I personally think the current manifold looks like ass and would have been so much better with the C6 LS2 intake manifold. Question is, what performance gain/loss would an intake swap of this sort net? Also, is the TBSS's TB 90mm?

The manifold was used to compensate for packaging issues, but that is not where the 5hp loss was. The loss is due to the restrictive intake and exhaust. Our 'truck' manifolds work much better than a C6 vette one would for our applications. The truck manifold provides a lot more torque down low than the C6 LS2 manifold. I assure you that if you swap the manifolds, it will make your truck slower. We need the added torque to get these heavy trucks moving off the line.

*Other options: There is another alterantive. You can do a swap and use the LS7 manifold. At ET Performance, we made a small bore (4") LS7 head to fit on LS2 engines. It will use all factory rockers, and you will be able to utilize the LS7 manifold.

[Tractor]

I was told that the loss in 5 horse power was due to the fact that the C6's fan is electric and ours is crank driven.

[TrailblazerSS]

This style intake is known for making better torque. The C6 style better hp. Heavy vehicles like the TB SS benefit from torque.

Probably all the changes, intake, fan, exhaust contribute to the 5 hp loss.

[SUVette06]

I was told that the loss in 5 horse power was due to the fact that the C6's fan is electric and ours is crank driven.


Think thats what I heard as well

[Fishhunter911]

well with that said... has anyone looked into and E-fan set up for these? or not a good idea?:undecided

[Ddubb]

Electric fan could be a good idea to reduce parasitic drag on the drive belts .. but Im not sure if the internal rotating assembly is balanced with the fan assembly on the end.
As for the intake manifolds, the difference in HP vs. Torque is usually due to the runner length / design from the intake plenum.
Long runners = More HP at Higher RPM
Short Runners = More Torque at Lower RPM

- Dan

[jimmyjam]

i've talked to someone who put a dual electric fan on a regular TB 4.2L, but he has to live with the check engine light staying on because of it. I wonder if an ECM tuner could mask that code from being thrown?

[BLK60SS]

You'd probably get a better hp gain by getting one of those electric water pumps by Meziere. Only downside is they are a little pricey.

[Crash 02]

Long runners = More HP at Higher RPM
Short Runners = More Torque at Lower RPM

- Dan

I believe you have the two reversed.

Short = HP
Long = TQ

[OurZoo]

Was there a noticeable increase in performance?

[SLAG]

So the real question is has anyone successfully swapped the car intake for the TBSS intake:undecided

[vette-ss]

Fans and intake....all for a 5hp gain. Is it worth it? I thought efans were advertised for some decent gains?:confused:

[BigD SS]

Fans and intake....all for a 5hp gain. Is it worth it? I thought efans were advertised for some decent gains?:confused:

If you do a search, you will see that most efans are netting the TBSS guys around 10-15rwhp. Pretty good gain if you ask me (on my list of "to do" for my TBSS). While your there, change the underdrive pulley. The two will be good for around 20rwhp.

[SLAG]

Has anyone put the LSx style intake on a TBSS? PICS? What all had to be moved? :confused:

[ltz03]

not really worth it as it has torque at a higher rpm, not sure if anyone has done it, but i dont think so

[treyster]

It should be as easy as setting the 2 next to each other and measuring the intake runner length. The longer it is, the more bottom end it will create, the shorter it is, the more top end it will create, assuming both have the same port area. Think of it this way: when the piston hits bottom dead center, the longer the intake port, the longer the column of air that is continuing to fill up the cylinder as the piston begins to rise (that's why the intake valve doesn't close at bottom dead center). As RPM rises, there gets a point where pumping losses start to outweigh the air column length and the engine needs a shorter runner.
Plenum size has become irrelevant for the most part with the advent of port injection because fuel doesn't have to stay in suspension like the old carb days. Getting rid of the neck at the MAF should help, depending on how big the hole is to begin with.