[DickH]

I have seen pictures of people with 99-04 4v intakes with modified runners, but I have not seen how they do it. I have tried looking at pictures of manifolds and cant see where they cut. Anyone have pictures of the process?

 

[SWEET2KSTANG]

talking about psr's or just ported? a few companies do psr's, kind of an extensive task. you also have to be a good cutter and tig welder as well.

 

[DickH]

I don't know what im talking about, I have just seen where people had modified manifolds and am curious about the process. I can cut and weld just fine so that isnt a problem.

 

[DickH]

This is what im talking about. I don't have a manifold on hand but am thinking about buying one soon, all I need to do is cut the bottom off, cut the runners and weld it back? I cant seem to find a picture of what it all looks like before the runners get cut, is it fairly straight forward and that easy?

 

[SWEET2KSTANG]

you dont have to cut the bottom off to do all that. most of that is for looks on the flats of the plenum. i personally do it without cutting the bottom off. you can have the runners modified as well, places like nazty's (i think thats the name) does that.

 

[Boostang]

i am also intersested in some before and after pics

 

[Lefty]

you dont have to cut the bottom off to do all that. most of that is for looks on the flats of the plenum. i personally do it without cutting the bottom off. you can have the runners modified as well, places like nazty's (i think thats the name) does that.

Yep; Nazty Performance (username "Nazman" on SVTPerformance)

 

[DickH]

you dont have to cut the bottom off to do all that. most of that is for looks on the flats of the plenum. i personally do it without cutting the bottom off. you can have the runners modified as well, places like nazty's (i think thats the name) does that.

I want to do the modifying myself, how can I shorten the runners without cutting the bottom off?

 

[bitemark46]

This is what im talking about. I don't have a manifold on hand but am thinking about buying one soon, all I need to do is cut the bottom off, cut the runners and weld it back? I cant seem to find a picture of what it all looks like before the runners get cut, is it fairly straight forward and that easy?

That is a pic of the inside of the bottom of the intake. In order to get to it on a 99-01 intake you have to cut the lower in half. Reducing runner length requires you to cut it in half. Don't cut no more than 2" off for a street car. If you don't have a spare intake and its your DD then have someone else do it or buy a spare and hack away.

-Mark

 

[Boostang]

i bought my imrc deletes from you^^ bwahahaha..

but do u have too cut the intake on a 96-98 model cobra too shorten runners?

 

[DickH]

Well I am trying to build a top end heavy 4v, shortening the runners seem like a way to help with that. Why isnt it a good idea for a street car? What are other things I can do to the intake?

 

[SWEET2KSTANG]

depends on how much you take off the runners. when you start going for high rpm's, you sacrifice down low. idea is to find a happy medium that will suit your needs. you are doing a c-head intake?

 

[DickH]

I don't mind losing some low end, I am content launching at 4.5k so whatever is lost below 4 isn't missed. I'm wanting to use 04 c heads but I'm having a hard time finding some.

 

[DickH]

Update, im modifying a manifold, here are pictures.

Done shortening the runners, now im working on porting the manifold and whatnot then it just needs welded.

 

[Mach Boy]

If you did all of it right you will see a very nice gain in HP. Naz's PSRIs along with some others were getting 20-30rwhp gains, but as stated earlier when you shorten the runner lengths you will lose power in the lower RPMs. If any of you are considering ORDERING a ported short runner intake (PSRI) you might want to research Naz and see if he is still doing them. He has had family and health issues recently so don't just go ordering one from him before you do some looking.

 

[DickH]

Im not too worried about lost power in the lower RPMs, looking at the graphs on the nazty performance website it really doesnt even look like enough to call a loss. Are there any other modifications to these manifolds that I could do while I am at it? After closing up the lower manifold, ill end up gaining a lot of volume, will a spacer still give any gains? As far as I understand a spacer just adds volume and helps with power, but now ill have almost the entire lower manifold for volume and thats a lot more than what a spacer will add.

 

[DeMello]

Why isnt it a good idea for a street car?

it is, just dont cut too much

mine are cut 1.5

 

[DickH]

You are on a Bhead motor if I remember correctly.

 

[DeMello]

You are on a Bhead motor if I remember correctly.

yes

nazmen of nazty performance does a badass port job and shortens the runners on 99-04 intakes for like 900 bucks. i wouldnt suggust doing it yourself

its much easier to do the 96-98 intakes, and we dont port them like the 99-04s

 

[DickH]

Yes I am aware that I can have a nice job done for 900 + cost of manifold. I however have everything needed to do this myself so all I need is the manifold so its like the rest is free. Even if I could have a little more from paying 900 bucks, the difference between whatever ill get and what I could get is not worth 900 bucks to me. Also there is some thing about paying to have **** done vs doing all my **** on my own. I enjoy working on my car and working on things for my car so this is just fun to play with.