porting 2g head to 1g intake?

[DiamondStar90]

can you port the 2g intake ports on head to match the 1g manifold?

 

[bryanwheat]

For the most part yes, can you physically make the bottom of the port as the 1g, no, there is not enough material on the bottom of the casting, but you can taper it. If you don't have a flow bench and someone experienced in doing this than you are wasting your time. You will ruin a head real quick just trying to open the ports.

 

[LiquidX]

Honestly, get a 1g head if you want larger ports. However the smaller 2g ports are excellent for velocity and it has a better design for air flow.

 

[underradar92]

I have a couple of 1g heads, I'd gladly trade for unbutchered 2g heads. Opening up the 2g head like that only to (maybe) match the flow of heads that can be had for about the cost of their weight in beer cans, is a waste.

But as mentioned above and in many previous threads... Yes, this can be done.

 

[Diamond Star Werks]

Honestly, get a 1g head if you want larger ports. However the smaller 2g ports are excellent for velocity and it has a better design for air flow.

Agreed. If you want to do this just switch to a 1g head. As if you open the 2g ports your basically making them 1g and there will be no advantage. It would be the same as having a 1g head and IM on there.

 

[DiamondStar90]

its just i dont have anyone locally selling a 1g turbo head with the water pipe needed to do the swap for cheap

 

[LiquidX]

Look on the classifieds or use a 2g manifold. The EvoIii/RVR manifold with a 1g tb is a huge upgrade.

 

[underradar92]

its just i dont have anyone locally selling a 1g turbo head with the water pipe needed to do the swap for cheap

How can this possibly be?

The EvoIII/RVR manifold with a 1g tb is a huge upgrade.

Worst/best kept secret in 4G63 world...

 

[LiquidX]

How can this possibly be?



Worst/best kept secret in 4G63 world...

I don't quite understand what you meant by that.

 

[TexasTurbo]

evo3 IM actually has a pretty small plenum which I would say is it's weak point.

You're definitely trashing that cylinder head IMO and in a lot of others' opinions if you start port matching it to a 1g IM. I'm sure someone will be more than happy to trade you a 1g head for that head AND pay for the shipping for the whole deal if you can pass off an unmolested 2g head.

Cliff notes : no stop it you're doing it wrong.

 

[LiquidX]

It's been proven to be an upgrade, it's provides lower end power using the shorter runners with higher velocity flow into the head. It's an upgrade over the stock manifold.

 

[JacksonAuto]

You can port match the head, but it will still neck down to the smaller 2g size. In order to get the benefits of the 1g manifold you need to open up the entire port on the 2g head to match the 1G.

The advantage to doing this as opposed to just using a 1g head is that you will also have the better flowing exhaust port on the 2g. Also, a lot of guys don't want to go through the hassle of putting a 1g head on a 2g car because of the difference in the sensors and such.

 

[underradar92]

How can this possibly be?



Worst/best kept secret in 4G63 world...

I don't quite understand what you meant by that.

The first statement, how can there be no locals in possession of the parts in question, willing to sell/trade them. Although I suppose in a sparsely populated area this is likely the case.

Second case, it seems to me that the intake head combo is well known to be an upgrade for many applications, while some (seemingly) refuse to accept the idea that the smaller (but actually straighter) intake port works better in most situations. Hence the duality of my statement.

TexasTurbo, IIRC, Buscher tested EVO8 intakes (functionally VERY similar to RVR/EVOIII) both in stock form and in an enlarged plenum modded version and saw little to no advantage in the enlarged plenum. I agree that a larger plenum should work better in certain apps, but the small plenum proved to be less of an issue than they had anticipated.

 

[LiquidX]

Thanks for the clarification, I was only referring to the latter half.

 

[DiamondStar90]

I have a couple of 1g heads, I'd gladly trade for unbutchered 2g heads. Opening up the 2g head like that only to (maybe) match the flow of heads that can be had for about the cost of their weight in beer cans, is a waste.

But as mentioned above and in many previous threads... Yes, this can be done.

ill trade you if you have the water pipes and stuff to do the conversion but im keeping my stock cams as i need them for the 97 cam sensor

 

[TexasTurbo]

It's been proven to be an upgrade, it's provides lower end power using the shorter runners with higher velocity flow into the head. It's an upgrade over the stock manifold.

It's only really an upgrade over the stock 2g smim, which has some restrictive characteristics.

I've had a 2g head on a 6bolt w/ an evo3 IM on my car for well over 2 years now. And I've battled the "smaller port" battle with people on this site before it became accepted that it was indeed an upgrade over some stock parts on a DSM.