b18a block, PR3 pistons, PR3 head, stock head gasket, unmilled. Ive heard everything from 11.4 to 12.2.

Also, for this setup, would a B16 IM and TB adversely effect horsepower? Is it worth it to get the SKUNK2 or ITR IM and TB, assuming I use CTR cams?

 

Actually I am getting anywhere from 11.3 to 11.6. The IM and TB from the B16 would not affect performance, but you can't go wrong with the ITR IM. In my opinion though an aftermarket IM such as the SKUNK2 should be done after all modifications to engine internally have been completed.

 

But flow wise, the b16 IM is sufficient for this mild setup? I dont want to spend 500 dollars for maybe 3-4 HP.

 

the b16 im stock is pretty good for most street motors and in comparison is worth the money to keep instead of spending 300 on a im you should put it toward something that really helps like cams or a computer.

 

I bought a book, "How to Build Honda Horsepower" by Richard Holdener. It includes dyno plots of a B16A manifold versus the Skunk 2 intake on a somewhat modified B16A engine (including Crower 401 cams, which are very similar to the CTR cams), plus another test of the B16A intake versus the ITR intake on both the B16A and a B20 2.0L LS/VTEC hybrid. Against the Skunk 2, while the Skunk 2 generated a lot more power above 8000 rpm, the B16A significantly outperformed it all the way up to 8000 rpm. Similarly, the ITR made a lot more power above 7600 rpm, but the B16A just whipped it from 5000 to 7600 rpm. If you look at the areas under the curve, the B16A probably out-performed both the Skunk 2 and the ITR.

Now, these were on mildly modified engines with about 170 peak wheel hp (B16A) and 200 hp (B20 LS/VTEC). For an all out engines reving above 9000 rpm, the Skunk 2/ITR would clearly be better. But if you aren't running big cams, you might consider saving your money and sticking with the B16A intake.

 

excellent, with the CTR cams I wont be reving past 8400. B16 IM = more tourque