RJM GTR Intake Lower Manifold...oh yes!

Originally Posted by bullitt5897

Ok so im going to chime in given that I have held an OEM, GTM and the RJM in my hands and on a table in front of me.

The proposed issue presented:
Why is the inside runner so "Rough"?

My Thoughts:
So what I feel we have here is an over critical look at the product based on pictures which does not give you a real understanding of the texture of the inside runners. Does the inside runner have a textured? Yes, however it is not much of a texture at all. The picture is very deceptive due to the lighting. The pre production unit that I got and should be identical to the one everyone else has received with the exceptions of some input from me on some minor changes.

The inside texture is very comparable to stock or a cast. Could it be smoother? Yes it could but one key item to remember is that this unit was designed with the intent that if you wanted you could port this thing an additional 5mm all around!!! In a Forced induction application these shallow grooves will not make much of a difference. In an N/A application you might see some improvement from polishing it but I would not bank on you making a ton of power... Maybe 2-3hp if that.

The outside jeweling was left at this level to help make sure this stays affordable for everyone. There is alot of machine time in these lowers and to go another step into smoothing the outside cosmetics is very doable and from my conversations easy to do. However, that cosmetic request could very well result in a few hundred dollar increase in price... So as a fellow consumer what do you want? Functional or pretty?

The current interior runners will not and I repeat will not hamper you. I along with several industry staples have held these in our hands. this isnt a "shitty" product but a well thought out and engineered device...

DE yes you can refine the product and polish it to a mirror finish but you and I both know that even with doing that you are not going to see a major increase in HP or TQ...

So lets be honest guys. What we have here is a a legit criticism but one that if you want done will cost you more $$$. Can you live with a cosmetic (in your opinions) issue or are you willing to actually pay $2200-$2300 for a perfectly polished unit? I would bet money that your would rather buy the unit as is for a Sub $2k price tag...