[MichaelDelaney]

the coolant ducts and center flange hole do not line up for the ITR IM and the GSR head. Secondly, the GSR intake ports are taller...there is a more direct angle or shot into the combustion chamber and so the port on the ITR IM flange has to be aligned in such a way that it spits the difference in height between the 2 intake port heights.Apparently there is no vacuum leak when you split the difference.

Anyway, you can have a reputable machine shop weld shut the coolant ducts on the ITR IM or have them weld on material and reshape the ducts into the same alignment as the GSR head coolant ducts. The flange bolt holes can be slotted so they line up by the machine shop as well. Obviously they would need the head to align everything.

So by the time you cost out the ITR IM and machine shop work, is it cheaper than a Skunk2 IM?... depends on your machine shop and where you got your ITR IM...but in most cases probably not...certainly much more hassle for the average owner with no ties to machine shop work...

you need to get the Helms manual and look at the comparative IM's since the Skunk2 and ITR IMs needs you to buy an ITR throttle cable, cable bracket, new injector O-rings, GSR manifold gasket/TB gasket, and an ITR compatible intake.

You probably have a tapered 70mm TB since a true 70 mm TB on an N/A setup is way too big. If so, what is the diameter at the IM end of the TB? Some taper from 70->62 mm like a stock ITR TB, some taper from 70 -> 64mm, and some taper from 70->66-68 mm like Erick's TB's.....in which case you have to cut the TB gasket opening to the same diameter,...the Skunk2 and ITR IM port on the plenum which mates to the TB is 64mm in diameter. So if your TB diameter is larger than 64mm you must increase the diameter on the IM plenum port as well (called port matching).

 

[MichaelDelaney]

there's a couple of retailers of honda oem parts on the net like A&H and H&D but your local parts dept at acura should be able to get the parts....

if you get the itr IM or skunk2 im the plenum port that mates up to the TB is 64mm. Just line up everything to see if you need to cut the opening on the gasket larger...tape it on...use a sharp scibe or needle and trace the opening carefully..get a sharpened pair of scissors and snip snip...

 

[MichaelDelaney]

you'll see what I mean when you get the IM and line it up with the tb....

 

[MichaelDelaney]

without cam changes : 4-6 whp up top...

 

[MichaelDelaney]

gee...do you mean a company would set up conditions to make their own product look as good as possible on a biased ad? I'm shocked! I didn't know that....

 

[MichaelDelaney]

Im sure its somewhere here in the forums but since I can only search topics and not content.

Everyone else can only search by topics too. So what are you saying? Search for me because I am too lazy to do my own work? Sorry I'm not to clear about why you added this comment onto your question.

I suggest you start by looking at stock ITR dynos and the powerband range. They're not hard to find on any honda website or go to honda's website when they released the ITR.

Then look at what happens when they move to a bigger intermediate cam that doesn't require a CR change to work after tuning but keeps the stock ITR IM and stock head without porting. The shift up for the peak tq in the latter case will be the cam's effect not the IM's.


That should show you where the IM's peak torque points are likely to be located on the rpm range and when it runs out of breath , since the torque dies at a certain high rpm range in both the stock and intermediate cam package dynos.

The ITR tranny's upshift landing points using the redline should tell or hint to you where the honda engineers wanted or intended to have the peak torque location to be.

 

[MichaelDelaney]

skunk2 has fatter runners....crap, i forgot the size of the pendulums(sp?).

there's a thread in the common topics where the exact dimensions were done for the runners and plenum for the stock IM's and Sk2 IM's for b18b and b18c1.