Stage 2 cams & cam gears and emissions?

[DaJackal]

Hello there!

My car is a '95 GS which needs a timing belt job to be done next year. When doing this it would be really easy to change cams and move on to adjustable cam gears. The problem is that I live in Finland and we have emissions here. Borders are the following:

HC max 100ppm (both on idle & revs)
Lambda value min 0.97 max 1.03 (on revs)
NOx not measured
some CO border, don't remember how much it is

The current mods are AEM CAI, eBay header, Magnaflow hi-flow cat, 2.5" exhaust all the way from the header, 55mm TB and NGK plug wires. The car just passed emissions rather easily with these mods, but I know it's running really rich after 4krpm so I ordered a SAFC II to compensate that. In addition to this an AEM Uego wideband will be installed too. The car is NA and it's going to stay that way.

Would throwing in a pair of Crower stage 2 cams make passing the emissions a PITA? It's the idle I'm worried about, of course. And if it would, do stage 1 cams make any significant difference or should I just stay with the stockers? If I decide to stay with stock cams, will I have any benefit from adjustable cam gears? Does SAFC II help me to settle the idle emissions?

The cas is a DD but is also used to humiliate Hondas every now and then. This is why I wouldn't want to sacrifice a lot of low rpm range in favour of higher hp numbers, so stage 2 is the max.

 

[cyexmaster]

Stage 1 is just a bit better than stockers, and I would think the SAFC 2 will help you out in the fine tuning of the engine. And the adjustable camgears really dont get you a lot of power but it will help you dial in the powercurve of the cams of course you will see gains from this but dont expect more than 10hp (and that's being really optimistic) from them. I would suggest that you look into some high comp pistons if your staying NA...

Hope this helped.

Other mods to consider are UDP's (under drive pulley's) and a bigger throttle...

 

[donniekak]

I passed emissions with crower 272's in my 4g63, however i was running ethanol. You do have a 4g63 correct?

 

[DaJackal]

Stage 1 is just a bit better than stockers, and I would think the SAFC 2 will help you out in the fine tuning of the engine. And the adjustable camgears really dont get you a lot of power but it will help you dial in the powercurve of the cams of course you will see gains from this but dont expect more than 10hp (and that's being really optimistic) from them. I would suggest that you look into some high comp pistons if your staying NA...

Hope this helped.

Other mods to consider are UDP's (under drive pulley's) and a bigger throttle...

UDP has been ordered already and is on the way. Throttle body is already the biggest possible (55mm w/ axle filed thinner = equals 57mm TB) since 60mm Jeep TB is known to cause emissions problems.

I'll be looking into Wiseco 10.5 pistons and Eagle rods when the engine shows signs that it needs a rebuild, but in a recent dyno run it appeared to be in good shape so that's a thing of the future.

 

[DaJackal]

I passed emissions with crower 272's in my 4g63, however i was running ethanol. You do have a 4g63 correct?

Why would I be writing to 420A zone if I had a 4g63?

And 4g63 turbo engine running ethanol has very little to do with a NA street car running pump gas. Sorry, didn't mean to be a smartass, but you kinda asked for it with your comment.

EDIT: If you asked that because the European model of 2g has a 4g63 non-turbo engine, then I can understand better. But my car is imported from US and has 420A.

 

[Fotowntalon]

UDP as stated is a good mod, but you are already ordering, I'd grab a Crank Scrapper for more power to, good cheap easy mod.

As for cams, I have no idea if they effect emissions or not, normally a lot of parts will state if they do when buying them (like coming with a warning for off-road use or something to that effect). Baring that I would say stage 2 or stay with stockers, lot of people barely notice a difference with stage 1's, or maybe look into cranes, they may have an in between spec (like a 1.5 equiv) which may be emission safe.

Make sure when you are tuning in the SAFC2 that they know about your emissions, you may not be able to get an optimal set-up with it without it effecting your emissions to much.

 

[LiquidX]

Unless you are going to dial in your cams with the adjustable gears then you are wasting your money. In all honest IMHO most people that get cam gears buy them either because they think they need to with new cams or because they "look cool". Hardly anyone takes their time with solid litters and a degree wheel to dial their cams to true TDC.

 

[cyexmaster]

Check out the modern performance 60mm throttle I got that obe and it's quite nice and I doubt it will screw you on emissions...

 

[DaJackal]

Check out the modern performance 60mm throttle I got that obe and it's quite nice and I doubt it will screw you on emissions...

I honestly don't think it's the TB that's the bottleneck here. 57mm vs 60mm has very little difference. (I have the 55mm TB that has its axle filed thinner = equals 57mm.)

 

[donniekak]

But my car is imported from US and has 420A.

Why in the world would you go through all that trouble for a 420a?

 

[cyexmaster]

I honestly don't think it's the TB that's the bottleneck here. 57mm vs 60mm has very little difference. (I have the 55mm TB that has its axle filed thinner = equals 57mm.)

Area of a circle: A= pi *r*r or 3.14(radius squared)

r = d/2 = diameter/2


57mm = 5.7 cm -->> r = 5.7/2 = 2.85 cm

60mm = 6.0 cm -->> r = 6.0/2 = 3.00 cm


A(57mm) = (3.14)*(2.85)*(2.85) = 25.505 cm^ squared

A(60mm) = (3.14)*(3.00)*(3.00) = 28.260 cm^ squared

So, 28.3 > 25.5


But the real benefit would be in having the intake manifold bored to the 60mm as well otherwise it wont make use of the full potential of the bigger throttle body.

And the more air you can get to the engine the more fuel you can burn, so you can make more power....

 

[Fotowntalon]

yet 57 is the most airflow you can do before you start to take away from your low end, whiih for an NA DD i find important, but i do however agree that IM port match is a must

 

[DaJackal]

Why in the world would you go through all that trouble for a 420a?

I didn't import it myself, I bought it from its 1st european owner. Because IT WAS CHEAP!

 

[DaJackal]

yet 57 is the most airflow you can do before you start to take away from your low end, whiih for an NA DD i find important, but i do however agree that IM port match is a must

^^^My point exactly. I'm a university level math student/part-time teacher, so I know my math how the diameter of a circle affects its area.

IM has been port matched, but it's been done quite quickly. Probably will get it extrude honed to improve it next year when it's time for timing belt change.


Oh yeah, and I'm going to find just basic stage 1 cams. I and my friend came to the conclusion that HC levels would rise way too much on idle with stg2's. I might update valve springs and rollers & rockers too at the same time if I find those parts for a good price, though I know that stg1's wouldn't need these mods. I just like to be sure.

We'll see how the SAFC II does, but plans are on the verge to change and Megasquirt is lurking just around the corner.

 

[RadDsm]

Sorry for going a bit OT, but I didn't know they had 420a's in Europe. I thought all the 2g n/t were 4g63.

 

[cyexmaster]

^^^My point exactly. I'm a university level math student/part-time teacher, so I know my math how the diameter of a circle affects its area.

IM has been port matched, but it's been done quite quickly. Probably will get it extrude honed to improve it next year when it's time for timing belt change.


Oh yeah, and I'm going to find just basic stage 1 cams. I and my friend came to the conclusion that HC levels would rise way too much on idle with stg2's. I might update valve springs and rollers & rockers too at the same time if I find those parts for a good price, though I know that stg1's wouldn't need these mods. I just like to be sure.

We'll see how the SAFC II does, but plans are on the verge to change and Megasquirt is lurking just around the corner.

I really woulnt spend the money for STG 1 cams ...IMO

And if your looking up megasquirt you really wont have nothing to worry about, I would suggest to spend your $$ on the megasquirt rather than STG 1 cam's...

 

[DaJackal]

Sorry for going a bit OT, but I didn't know they had 420a's in Europe. I thought all the 2g n/t were 4g63.

All originally european 2gn/t's are 4g63, but there are rather many 420a's that have been imported. Mainly because they are not worth a sh*t in the US, but for example in Finland a 2gn/t still costs around 6-8 thousand euros (~8-11 k$). And yes, I do hate our car tax policy.

 

[DaJackal]

I really woulnt spend the money for STG 1 cams ...IMO

And if your looking up megasquirt you really wont have nothing to worry about, I would suggest to spend your $$ on the megasquirt rather than STG 1 cam's...

I'm not going to buy them new, only if I find a used pair for a decent price via classifieds. The car is going to stay in our family from now to eternity, so why not make things right the first time when the timing belt is off and cam changes are easy.