Ls1 cam tuning?

[MasterV8]

Hi, I'm a new member here, I have a cam not yet installed, Comp cams Si5 231/237 v1 & been doing a little reading on emissions.
Is there anyone in the UK that will tune LS1s preferably in the northwest & is it likely to pass emisions? I have all supporting mods & PRC Stage 2.5 5.3L CNC Ported Heads.
Duration @.050 is 231/237, LIft is .589/.595 and available on a 112 LSA

[monkfish1]

Whether it passes emmisions or not is primarily done to the cam choice. Doesn't matter who tunes it. That cam is unlikely to pass IMHO.

[stevieturbo]

What emissions limits do you have to meet ?

That will dictate how hard or easy it is to pass..and I'd disagree that it makes no difference who tunes it.

In theory it should make no difference who tunes any car and it should perform or run the same...reality is far far from that.

If it's the full on UK cat based test, that cam will be a massive struggle

[hsvgts454]

3/4 off the modified cars on this forum wouldn't pass a reel mot test
Even ones with the smaller cams fitted!

[stevieturbo]

hsvgts454 said:

3/4 off the modified cars on this forum wouldn't pass a reel mot test
Even ones with the smaller cams fitted!

So do you all get fake MOT's ?

[ArnieVXR]

John Sleath Racecars is worth a visit. North East, but will build a map using his rolling road.

[Boosted LS1]

stevieturbo said:

So do you all get fake MOT's ?

Yes, just say its a rover v8 and pass the 'visual' lol.

[stevieturbo]

Boosted LS1 said:

Yes, just say its a rover v8 and pass the 'visual' lol.

I know MOT's over there are bad...but now they sound even worse ! lol

[MasterV8]

stevieturbo said:

What emissions limits do you have to meet ?

That will dictate how hard or easy it is to pass..and I'd disagree that it makes no difference who tunes it.

In theory it should make no difference who tunes any car and it should perform or run the same...reality is far far from that.

If it's the full on UK cat based test, that cam will be a massive struggle

It would be a UK mot(not sure of what the limits are for emissions here), so I'm guessing all garages do an exhaust sniffer test as standard which is where it would fail.

I've had the cam for a while now, I bought it because it met the goals I wanted for the car at the time without going FI, but never found the time/weather to install it. I have EFI live but I've not had time to imerse myself in it apart from deleting AIR & rear o2 codes from having headers, so a company in the US was going to tune it with data logs to get it up and running then I'd look to get a dyno tune to dial it in.

The thing is it's not a daly driver so I'm tempted to shove it in there anyway after I have this years mot, hell if it fails next year I'll remove it and go with something else! atleast I'll get some use out of it

[stevieturbo]

MasterV8 said:

It would be a UK mot(not sure of what the limits are for emissions here), so I'm guessing all garages do an exhaust sniffer test as standard which is where it would fail.

It would be helpful if you specified what vehicle, what age, etc etc

Your profile seems to picture an American vehicle.

If the vehicle isnt on the UK database, then it might revert back to basic emissions test which should be very easy to pass.

So again, you need to find out exactly what the limits are you need to meet.

If it's a full UK CAT based test, then it will be difficult, but trial and error.

But at the same time, if it's a full UK cat based test you also need cats etc fitted too.

[MasterV8]

It's an 02 Camaro SS,LS1, import, posted it in this section because searches for LS based tuning lead me here & engine similarities.

I know the SS doesn't show up on the UK database which made it difficult to get insurance because everywhere only had European Z28 listed.
It has LTs and high flow cats fitted & forgive me if I sound like a complete noob but do you mean the emissions standard of the vehicle or the particular testing station?

[sheepdip]

It helps when the LS1 is in a 70s car!

[mikeyb1987]

ArnieVXR said:

John Sleath Racecars is worth a visit. North East, but will build a map using his rolling road.

I don't agree with this. OP - perhaps PM me first before considering going.

[ARAF]

stevieturbo said:

Boosted LS1 said:

Yes, just say its a rover v8 and pass the 'visual' lol.

I know MOT's over there are bad...but now they sound even worse ! lol

I think there's a fair amount of pub talk in there - plus the number of cam'd cars is relatively small. Maybe HSVGTS454 is trying to say that all of the Monkfish and Walkinshaw small cams will be fine, but the home-builds could have problems.

[stevieturbo]

MasterV8 said:

It's an 02 Camaro SS,LS1, import, posted it in this section because searches for LS based tuning lead me here & engine similarities.

I know the SS doesn't show up on the UK database which made it difficult to get insurance because everywhere only had European Z28 listed.
It has LTs and high flow cats fitted & forgive me if I sound like a complete noob but do you mean the emissions standard of the vehicle or the particular testing station?

The emissions levels you need to meet for the most part will be dependent on vehicle and vehicle age.

Testing stations will...or should all be the same. So not 100% sure where your US vehicle will fit into this.
If Richard was here he'd be able to advise as he runs a very similar vehicle.

But if you can get the MOT first, swap the cam...then see how things go. Worst case scenario you'll need to swap another cam for next years MOT

sheepdip said:

It helps when the LS1 is in a 70s car!

Even 1980 is a doddle too ! lol

Although at same time...emissions here ( Northern Ireland ) is the only one part of the test less strict than on mainland UK.
Everything else is tighter though ( and far less open to "friendly" testers as some guys here seem to rely upon based on earlier posts ) as all test centres are government run.

[hsvgts454]

MyM8V8 said:

What a bloody stupid comment to make on a public forum. Talk about foot and mouth. Nob.

I'm just stating facts

And don't call me a nob

[jameshsv]

Is it popcorn time.

[MasterV8]

After a long debate with my brain and trawling through LS1tech posts I've decided to respec my cam. I've looked on the mot annex and the Camaro is indeed listed but VXR 5.7 & 6.0 allow 0.3% co in natural idle test but the camaro is 0.5% would this affect cam choices?
Looking at 228/228 available on 112 - 115

Edited by MasterV8 on Friday 30th January 21:39

[KMud]

The 115 would be -2 degrees of overlap and your best chance at emissions, the 112 more like 4 degrees of overlap and choppier.

Who has the biggest cam that passes emissions? My 222/226-115(+3) hasn't been tested, but should pass. That's -6 degrees overlap.

[stevieturbo]

MasterV8 said:

After a long debate with my brain and trawling through LS1tech posts I've decided to respec my cam. I've looked on the mot annex and the Camaro is indeed listed but VXR 5.7 & 6.0 allow 0.3% co2 in natural idle test but the camaro is 0.5% would this affect cam choices?
Looking at 228/228 available on 112 - 115

CO2 is not tested, CO is

Whilst 0.5% is a fraction higher...really not enough to allow you to realistically change cam profile.

The wider LSA for an given profile will be easier to pass as generally it would have less overlap

But one thing about LS's, you really dont need a tight LSA and wild cam to get great results.