22 replies to this topic

[RallyRed]

Hi,

 

Any LS2 gurus..?

 

The Commodore LS2 engines have the 4 x steam ports on top of the engine.

From what I can tell, the rear 2 are just blocked off from factory.

The front 2 are piped together, and run off to the top of the radiator.

 

I'm assuming these are deemed to be at the highest point on the engine, and as such, are there to port any trapped cooling circuit air,

( from the last refill) back to the radiator. 

 

My questions

 

1 - why have 4, then block off 2 of them?

 

2 - some USA suppliers supply kts to tie all 4 together ( seems logical) and run to the top of the radiator. WHY??

 

Ta in advance.

 

 

[Bigfella237]

There are ports in the front and rear of each head because the heads are interchangeable left to right, same reason there are temperature sender ports in both heads.

 

Early engines did in fact come from the factory with all four steam vents plumbed, it was only later when space no longer permitted under the manifold that they decided just to block off the rear ports, basically just the factory cutting corners.

 

Most performance engine builders will recommend plumbing all four ports just to be safe.

 

They are needed on LS engines because the outlets (to the radiator) are in the block not in the manifold like earlier designs, so pretty much the entire cylinder head is above the level of these outlets.

[RallyRed]

I plumbed my two into a joiner in the top hose. This is the same as going to the top of the radiator....only easier to rig up.

I've had no issues.

Ta Daz...

Like this?

 

My concern is that the actual turbos are higher than anything else...will the pressure push any air out??......is yours similar?

 

Thanks

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[grumpy xu1]

As big fella has stated, plumbing the 4 corners like you have stated is the smartest move you can do & will most probably save your engine ! The like of trick flow ect do ready made kit's, ideally if you can link driver rear to passenger rear & then driver's front to passenger's front & then rearto front & then to the highest point in the radiator that you can & all conections being slightly higher than each other to avoid trapping any air or steam you will be set. & yes the later manifold's don't have the clearance under them for the rear steam line as the vt ls1 (shit) manifold & injectors did. Ipra lx has done his old using earls, great job. Cylinders 7 & 8 suffer by not having the steam ports when "hotted up" no pun intended especially! Gary.

[RallyRed]

OK thanks .....hope with a re jig......and a good burp, its all good.....sounds like a baby!!........buuuurp

[RallyRed]

As big fella has stated, plumbing the 4 corners like you have stated is the smartest move you can do & will most probably save your engine ! The like of trick flow ect do ready made kit's, ideally if you can link driver rear to passenger rear & then driver's front to passenger's front & then rearto front & then to the highest point in the radiator that you can & all conections being slightly higher than each other to avoid trapping any air or steam you will be set. & yes the later manifold's don't have the clearance under them for the rear steam line as the vt ls1 (shit) manifold & injectors did. Ipra lx has done his old using earls, great job. Cylinders 7 & 8 suffer by not having the steam ports when "hotted up" no pun intended especially! Gary.

ta Gary....I watched Tricks Youtube of their kit......seems good.   Ta mate.

[Bigfella237]

Geez I would'a thought those O2 sensors would overheat in no time flat being so close to the turbo outlets?

 

There should be coolant circulating through those steam vent lines all the time in parallel with the top radiator hose anyway, so even if they have to run up above the level of the radiator tank and back down, the circulation should still push any air bubbles through into the radiator.

 

So long as any air that gets into those ports ends up under the radiator cap then you should be fine.

[Bigfella237]

Oh sorry, are you saying the turbos are water cooled as well, and you're worried about air trapped in the turbos?

[RallyRed]

Ok...appreciate the feedback Bigfella..yeah...Im paranoid about heat soak as it is...thanks for pushing me over the edge!!,,,....have top spec heat socks on the plug leads etc..might slip a couple over those over the sensors as well. But I always think that sooner or later, heat is heat is heat.

I lay awake at night thinking a Harrop S/C would have been soooo much easier!!!...but that;d be easy.

Oh sorry, are you saying the turbos are water cooled as well, and you're worried about air trapped in the turbos?

air trapped anywhere...to me that is bad..as it

A) doesnt cool, and

expands like buggery and ends up pushing water out.

 

That smiley , was a ???

 

ok, so I see a capital b, = smiley??

Edited by RallyRed, 12 October 2016 - 08:59 PM.

[Bigfella237]

If you do have trouble with those O2 sensors running too hot, Innovate Motorsports do a bung extender with a heat-sink built-in that may help...

 

http://www.innovatem...&cat=250&page=2

http://autoplicity.c...-extender-hbx-1

 

[grumpy xu1]

Or reflecta sleeve, mate. Autobarn sell it, you can also get it in a velcro option for the o2 sensors im meaning, works good on alternator & starter wires too ! Similar to spark plug lead sheilds in a way. Gary. & Wouldn't the turbos be oil cooled ?

[grumpy xu1]

Holy crap, how do do you change the plugs in the ve ? Can anyone remember where to get the sleeves to stop your arm getting burnt by the exhaust (like a really long glove basically) i can't remember but i really would like 1 to work on the cars without any little hot moments! Gary.

[Bigfella237]

 Wouldn't the turbos be oil cooled ?

 

All turbos are oil lubricated/cooled but some are also water cooled...

 

Edited by Bigfella237, 12 October 2016 - 09:36 PM.

[RallyRed]

yeah, they are ball/roller bearing type....oil and water. 

4 lines per turbo.

 

Also, thanks for the other info re: the heat stuff and the extender..

[grumpy xu1]

I need to carry a print out about this steam vent topic, it's a repetitive question everywhere atm. I don't mind giving the advice mate, if it saves someone. Especially if the engine could die. Bomber i know that you don't like the ls, but mate they really are a good thing, & reasonably oldish in some aspects compared to the rice turbos, which are very fast. But I'd happily watch paint dry before i talked 1j ect ect if you could cam only a 6 speed standard headed 304 gmh engine & make 380hp at the tyres for 6k everyone would do it & me 1st. But the gm needs 3 x the $$$$ i had someone come up to me today & say this engine builder said ls1's continuously through rod's "bullshit" put a set of arp bolts in the std rods & 550 hp n/a no issues, keep the water out of the intake would be my advice, if you have a otr don't speed through water. But so many clowns do ! If you service them with moly 10w40 they should easily get 300,000 klms unopened i do believe that the decks are not true from side to side on a few of them & this could be a issue to address on a thorough rebuild pull the valve covers of & check the rocker rubbing in the head area & you'll know what im saying. Bang for buck they're good. Gary.

[grumpy xu1]

I didn't realize about the water cooling with the turbos, i have always been a bit shy of going the turbo route, but there is some cheapish (not yours obviously) turbo options around these days. I saw 1 in the states running chinese turbo ect pulling 550 hp ish on a pretty old ls1, would be interesting to see the amount of time it lasts ? Probably a good idea on a cheap engine. But still interesting. Gary

[RallyRed]

ta Gary....yeah the turbo route is not my idea...to me the best bolt on bang fot $$ s just get a Harrop S/C thrown on .

Its been done a million times and is tried and true.

 

the GTS is my sons car and he wanted to do something  a little different. Its going to be a good thing I think, but it does seem we are doing the R&D on the fly.

 

My only real concern is the amount of underbonnet heat it will make.

[grumpy xu1]

Hi Col, Im not saying that i don't like the turbo idea, i don't have a lot of experience with them though. I think that they're the way to go apart from a positive displacement super charger. I'd love a little turbocharged ls in a lc or lj actually, but it's a lot of money to tie up. When you can buy a new vf ss Ls3 for around 45k & you'd easily spend that on a torana like that. Gary.

[RallyRed]

Yep..agree mate.  I just bought a new VF2 SS ute...304kw out of the box..that around 413 HP.

 

Back n the day, the old performance cars were around 300hp!!.....

[grumpy xu1]

Hi Col, sounds the goods mate cam it & tune it & it'll be 400+ rwhp easy as & heaps of torque & fun ! I'd love a vf Ls3 Gary.