C210 Exhaust

[Socrates]

I am going to get a better exhaust for my 1978 C210 Skyline (L24) Fully Stock

I have the following options:

1. Extractors, 2.25" piping to lukey sports muffler to 2.5" turn-down tip - $970 all supplied and fitted at 1 shop

2. Buy extractors from another place ($440), install myself + $60 Engine Gasket = $500 then take to another shop to do 2.25" piping to sports muffler to 2.5" turn-down tip - $430 = $930

3. 2.25" piping to lukey sports muffler to 2.5" turn-down tip straight off existing engine manifold $400

If I choose option two, there is the chance that the manifold bolts could snap as they haven't been touched in 32 years, is the risk worth it?

What would you recommend for me?

I have also posted in WA thread.

[jrh001]

Hi,

Always keep in mind what the car is worth as you put more $$ into it. If you're just after a nice exhaust note, option 3 might be enough. However you do have a leaking exhaust manifold to fix, so maybe it's got to be removed anyway and you could replace it with extractors. Oh... and it might be a good idea to check your insurance - in case they consider it a 'modification'.

JH

[Factory 5]

For a bog stock L24 2.25 is on the large side.

If your not really planning any other supporting mods it may be too much.

If turbo or nics aftremarket carbs/ecu injection is an option in the future then cool...

Have you asked for the same quote on 2 inch?

In my old sigma from years ago, it had a 2.6 4cyl, worked. when i went to 2 inch it lost some torque in the bottom end, but revvvvvvvvved like a motorbike.... 2.25 on a 2.4 engine is 'just' pushing the limits i think...

and the manifold bolts, well what i have done (on 4 different L24's) is just as i pull up in the garage, pop the hood, let it cool for a little bit, and while its still hot, spray a heap of wd40 on the studs/nuts. then leave it for an hour, then do the WD40 again but cold this time... and let it soak until the next day. they come undone so much easier then!

Dont use air tools, its why 99% of exhaust shops snap them, too much too quick.

if your having trouble undoing the nuts, get an extension for the socket set... makes it SO much easier. can be done in under an hour instead of 3 or 4! (no joke, its fekking TRICKY)

oh and pm send about extractors....

[Socrates]

In light of more information I have added a 4th option

Extractors to existing 1.75" pipe, (remove existing resonator) to lukey sports exhaust to 2.5" turn-down tip.

or should i change pipe to 2"?

MAG86: I haven't asked for 2", in my view going up 0.25" of an inch isn't going to do much, or does it?

[Socrates]

numbers 1 and 2 are no longer valid.

Revised options are as follows:

1: Extractors,2.25" piping, resonator, lukey sports exhaust, 2.5" turndown tip. = $1120

2. Extractors ($660 installed), existing 1.75" piping, new resonator, muffler(~$250) + 2.5" turndown tip (~$40). = ~$950

3. Existing manifold, existing 1.75" piping, new resonator, muffler(~$250) + 2.5" turndown tip (~$40)= ~$290

That's my options.

I want number 1, but don't want to spend that much so I'm fine with number 2, BUT will it bottleneck at the entrance to 1.75" piping?

Edited April 13, 2010 by Socrates

[Silent Shadow]

i say dont bother with the resonator. get the extractors to a straight 2.25 pipe and a straight-through muffler.

and dont bottle neck!

[Socrates]

Alright i got exhaust done today

extractors, 2inch, resonator (hotdog), flow through muffler. $790 installed

Now my problems:

Extractors leaking and making hissing sound under load + fumes in car. = will take back to shop to get rectified

Heat riser, i was told that my car needs a heat riser, to warm up the fuel in the carby before it gets into the engine so it can burn better.

Exhaust shop can't make a heat riser from the extractors.

I can feel the engine surging when I put my foot all the way down, when it didn't before.

Is this something that can be fixed with a tune or will I have to either rig something to heat the fuel or just put back the old exhaust manifold?

I am planning to get carburettor overhauled and the choke pull of fixed which currently is stuck closed, until the heat opens it (which now i'm worrying about cause there's no heat riser so it's going to take longer to open and it's going to drive like crap for longer)

any help appreciated

[coupe72001]

Fix the immediate problems before you make any elaborate plans.

1. Get rid of the exhaust leak. Extractors can be a bugger to prevent leaking if they are thicker, that is they stick out further from the head - than your inlet manifold. (Given only one bolt and washer is supposed to be clamping both the extractors and the inlet manifold to the head.) Your extractor place may need to make up some washers with little lugs welded to them to accommodate for the difference in thickness; it's probably only a couple of mm, but that's enough for exhaust to escape as I have found (emerging from my car smelling like smoke, eyes watering etc).

2. Get the carby rebuilt. The single carby is refreshingly cheap and easy to rebuild. I paid about $160 for an overhaul about two years ago.

3. If the car isn't right at this stage (and I'd be surprised) review your other options.

Good luck!

[Socrates]

Thanks for info

What do you mean by not right?

I know it's currently running rich and is real slow accelerating in the mornings and blows smoke occasionally.

Is that what you mean?

[jrh001]

Hi,

He's saying you should fix the exhaust leak first and then the carby.

That might fix the majority of your problems. 

good luck,

JH

[Socrates]

OK i see, just droveto tafe now, cold start.

Drove absolutely shit, press accelerator and it coughs and chokes then starts to rev up, when normally it would only do it once or twice.

Is there anything else i can get to heat the fuel without using a heat riser?

[Silent Shadow]

Park it in the sun.

[coupe72001]

I've never heard of a single carb c210 with extractors (and I've driven plenty) needing a heat riser. I think the problems you have are related to poor carby cond or the exhaust leak.

Who told you that you need a heat riser? Don't trust/believe them.

[Socrates]

Place Called carburettor specialists, who said that he sees it all the time when extractors are put on and continued to explain how the fuel needs heat to become a mist to burn otherwise it will surge and etc.

This is the place that quoted me $620 for carburettor rebuild/overhaul, ~$360overhaul, $110 choke pull off (broken), rest labour.

[D-limo]

Go twin carbs!

[Silent Shadow]

ok in all seriousness:

i had a chat to my mate about your problem. he is a speedway driver (won qld rookie of the year) in multiple classes and is also a pit mechanic for another driver.

he said the fuel heat riser thing is bullshit. in his commodore race car all the fuel lines are actually heat shielded because once fuel gets hot it evaporates and that's no good.

these were his pointers/advice:

-good chance that the bloke who did the work bumped some settings on your carb or something connected to it when he did the install. check all your lines. check the tuning.

-carby could be f**ked, period. just get another one.

-you may have put bad fuel in your car recently and has clogged the fuel filter. check fuel filter and replace if necessary.

pretty sure that was it. but yea ive had a c210 with extractors and standard carby without any problem too. doesnt sound right.

and that dude sounds dodgy. beware!

[Socrates]

Thanks for the advice mate really appreciated.

Got the carby tuned and it's running sweet now, just when it's cold(engine) and say driven for 5min and choke comes off it goes down to ~500rpm and tries to stall.

On the other hand I've found it has more power now as well, possibly a mix of extractors and good tuning.

Regarding previous problems,

Fumes - My Jap spec stovetop tail lights weren't sealed properly and when a window was opened it vacuumed the fumes from the rear outside the car through the gaps into the cabin.

All siliconed up and no more smells.

Extractor hissing - Been back to exhaust place, they say the extractors aren't leaking but the car still makes a hissing/muffled tapping sound when under load. Exhaust place says come back after the valve clearances have been reset and a service has been done.

Heat riser - Not needed

Surging - Carburettor tuning fixed majority of that, very rarely surges unless I'm in too high of a gear.

That's what I'm at now, I will keep you all updated on this

[Silent Shadow]

not a worry mate.

can you explain this 'surging' to me?

[Socrates]

Surging is like bursts of power, instead of all the power going on at once, it has small bursts of power and slowly accelerates until approx 3000rpm where it gains more power and accelerates rapidly.

[coupe72001]

I'm very relieved that you didn't pay $620 for a carby rebuild, that is OUTRAGEOUS.

The car is bound to run a little average when cold, choke or no, they take a bit to warm up. I would mostly worry if the car ran poorly when hot.

Grab some tools and a service manual, and have a go at checking your valve clearances, ignition timing and cam timing. These things aren't to hard to check, but they all make a fair difference to how the car runs.

Good luck!