Jou ma se port!

[Vlade]

Since I'm a real SR20 noob... whats the differences between high port and low port...

Post a pic, get technical... wack me with information

[Gary57]

I think its got to do with the Valve angles, CA18DET is 45 degrees (shit) SR20 is more like 28 degrees (closer to ideal).

Why Vlade you want to go SR20??

[HancoB]

The highport SR20 is good because it has a more free flowing head design, and comes stock with a more aggressive intake cam profile.

The fuel injectors are easy to replace on a high port. They are not so easy on a low port.

The IACV/AAC valve is a bitch to replace on a high port. It's easy as hell on a low port. Also, on a highport, you'll typically have more trouble cleaning the throttle body or adjusting the TPS, because it's so far down there.

I don't know for sure, but it's probably easier to remove EGR/BPT on a highport than it is a lowport unless you can get custom block off plates for cheap. With a high port, you have the option of installing intake runners from a JDM SR20.

[Sokar]

The Low port is the Traditional Intake layout (think of the CA's intake and any S14's you've seen)


The High port is the funky one with the runner coming up and over the intake plenum.


Pics are crappy angles, got them of nico, you get the drift though...

[Gary57]

Ok but are there any differences in the head or is it just the manifold?? Also which is the better motor??

PS: what is the difference between the Red top and Black top, besides the colour of it.

[Hype]

Those engines look like they are the FWD variants..?

Are there major differences between the FWD and RWD variants on regards to the valve angles?

[veecee]

yup those are FWD,

no difference i think with the ports

the low port's manifold bolts directly onto the head, just like the ca18det...

hte high port motor has castings/protrusions that stick out from the head at an upward angle that the manifold bolts onto!

[Vlade]

nah not going SR20... just everyone keeps talking about highport / lowport and I got no idea what they are talking about, I knew it was different type of engines though...

[Doctor G]

Highports and JDM SR20's are the same thing.

The lowport is a better head design. Especially in NA form where they have roller rockers for less friction. The low port NA makes more power than the high port even though it has much smaller cams. A highport intake cam in a low port NA head makes about 18wkw difference IIRC!!

I'm not sure if the DET lowport motors have roller rockers. Will have to check.

But, if you're going turbo, then a redtop DET is good enought for 99% of the people. There are more aftermarket parts for it and they are more easily attainable.

The VVT gimmick doesn't do anything for a built DET ito power.

[Gary57]

The VVT gimmick doesn't do anything for a built DET ito power.

Why so??

[Doctor G]

It was put in for mom's driving the car to the mall. To give nice smooth power at low rpm.

Any tuner who modify that motor disengages that VVT asap. So if you spend the extra R6k on that motor, make sure you budget for a normal intake cam gear also...

[veecee]

so if i get a highport it will be ok then???

an S13 sr20det???

[jon]

The general consensus among the yanks (nicoclub) and aussies (nissansilvia) is that the S15 black-top is not worth the extra money.

When swapping in a SR most opt for a non-VVT engine. The s13 red-top and black-top are almost identical, both came with T25 turbo's. Only the S14/15 black-top had a T28 and VVT.

If you buy a black-top from an engine import place you need to be very careful that you don't end up with a S13 black-top when expecting a S15 version.

Read about differences here---> <a href="http://forums.nicoclub.com/zerothread/306956" target="_blank">SR20DET Info</a> <---

[veecee]

'cept that the VVT blacktops have a nice big hump near the back of the tappet cover and the normal non-VVT blacktops have a flat tappet cover.

so its not that difficult!

[jon]

You are 100% correct but not everyone is aware of that.