My first port Job of an Exhaust Manifold

Cgillies86 · Mar 4, 2006

It's not perfect, but good enough for a $1000 car. I had a few accidents when I ported it, but its not that bad for my first attempt at porting an exhaust manifold. let me know what you guys think.

LA97GST · Mar 4, 2006

1. You completely destroyed the roundness of the outlet. Not very good.
2. Looks like you took down the airfoil inside which is also not very good.
3. Did you touch the runners?

Not trying to be mean but....

Oldman chime in on this if you get a chance please.

Cgillies86 · Mar 4, 2006

LA97GST said:
1. You completely destroyed the roundness of the outlet. Not very good.
2. Looks like you took down the airfoil inside which is also not very good.
3. Did you touch the runners?

Not trying to be mean but....

Oldman chime in on this if you get a chance please.

I had to take down the airfoil in order to port the side of the outlet. The Vfaq said to take it down also. The runners were already done by the previous owner. The outlet fits my 7 cm gasket pretty well. The angle that it is leaning on exagerates the problem.

DSM007 · Mar 4, 2006

Check the runners and make sure they are not ported bigger than the gasket so it doesnt blow the gasket out,you dont really need to mess with the runners these days they found out because they say it is supposed to help with velocity.....I dont think it matters because the turbo itself is already in the way creating backpressure at low rpm's.

Now on with the outlet,you cant help but to hit the divider when you port it,as long as most of its still left which I see is ok in my opinion.Those little slipups I see there,so long as they are not bigger than the outlet gasket you will be ok,Im sure you got a stainless or a solid metal 7cm gasket,if the little messups there are bigger than the gasket just line the gasket up against the outlet with your mounting bolts and port the gasket to match it.

The inlet going into the turbocharger,if the turbine inlet is now smaller than the outlet of the manifold after your done porting the manifold,take the inlet of the tubine side of the turbocharger and port it too so it is slightly larger than the outlet of the manifold,the idea is to prevent the exhaust leaving the manifold from running into a step in the way on its way entering the turbine,it will also prevent the reversion of gases at low rpm's too(old formula1 practice there),also thats the idea with the porting of the inlets of a manifold bigger than the outlets of a head too by some people,to make a step bigger on the inlet than than the outlet to stop reversion of gases and help with low end torque.....just like a torque step header does but built in a different way

Dont forget antisieze on the studs and no spray's or silicone's on the mounting surfaces,I found exhaust gaskets dont work well with adhesives in my experience.

Hope this helps and go put that bad boy on there

Turbo Shogun · Mar 4, 2006

Hahaha, I did the same thing in the same spot. I got a little overzealous with the grinder and took off much more than I bargained for.

I did my turbine inlet and it turned out MUCH better. I exercised a little patience in grinding off little by little and it's completely round and conical, like a bellported housing should be. I don't think it'll be a problem.

Cgillies86 · Mar 4, 2006

DSM007 said:
Check the runners and make sure they are not ported bigger than the gasket so it doesnt blow the gasket out,you dont really need to mess with the runners these days they found out because they say it is supposed to help with velocity.....I dont think it matters because the turbo itself is already in the way creating backpressure at low rpm's.

Now on with the outlet,you cant help but to hit the divider when you port it,as long as most of its still left which I see is ok in my opinion.Those little slipups I see there,so long as they are not bigger than the outlet gasket you will be ok,Im sure you got a stainless or a solid metal 7cm gasket,if the little messups there are bigger than the gasket just line the gasket up against the outlet with your mounting bolts and port the gasket to match it.

The inlet going into the turbocharger,if the turbine inlet is now smaller than the outlet of the manifold after your done porting the manifold,take the inlet of the tubine side of the turbocharger and port it too so it is slightly larger than the outlet of the manifold,the idea is to prevent the exhaust leaving the manifold from running into a step in the way on its way entering the turbine,it will also prevent the reversion of gases at low rpm's too(old formula1 practice there),also thats the idea with the porting of the inlets of a manifold bigger than the outlets of a head too by some people,to make a step bigger on the inlet than than the outlet to stop reversion of gases and help with low end torque.....just like a torque step header does but built in a different way

Dont forget antisieze on the studs and no spray's or silicone's on the mounting surfaces,I found exhaust gaskets dont work well with adhesives in my experience.

Hope this helps and go put that bad boy on there

Thanks for the info, I am gonna port the turbo inlet next weekend. I will make sure to make it larger than the outlet on the exhaust manifold. Is it ok to make the inlet on the turbo exhaust housing larger slightly than the 7cm gasket?

Dieselboy · Mar 4, 2006

You need to finish grinding down that ring in the collector. Looks like you've got most if it, but smooth the whole thing flat all around.

Is that a brand new Evo III manifold? If so, don't bother with the runners. The new cast used is good quality, and also VERY tough since it has a high nickel content (which also makes it much more durable and less prone to long term wear and cracking), so take your time with that thing. I would also grind the center divider down about 1/3 its stock length (if you haven't done so), then shape the edge into a "V" shape so that the exhaust merges smooth into the collector.

DSM007 · Mar 5, 2006

Cgillies86 said:
Thanks for the info, I am gonna port the turbo inlet next weekend. I will make sure to make it larger than the outlet on the exhaust manifold. Is it ok to make the inlet on the turbo exhaust housing larger slightly than the 7cm gasket?

I dont see how it would hurt,there isnt a fire ring on the gasket like ya have with a head gasket that could blow out or something,its just a flat gasket that isolates the two mounting surfaces from each other,as long as they are both perfectly flat ya should be ok going a tad bigger on your turbine side(like a 1/16 of an inch bigger) without a risk of blowing the gasket out or leaking,make sure its a solid stainless gasket you use because those are pretty much blow proof and another plus is that you can reuse it many times.

The Top DSM Community on the Web

My first port Job of an Exhaust Manifold

Cgillies86

Attachments

LA97GST

Cgillies86

DSM007

Turbo Shogun

Cgillies86

Dieselboy

DSM007

Similar threads

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds