Manifold

[FAO Tom]

Tom..

I know you have told me before, but could you let me know what putting tape on your manifold does?

Thanks

Daz

 

[Ian (Geforce)]

Gives the car an extra 26Bhp and 21lbs of Torque.

Right Tom?

 

[Daz155HGT]

Re: Re: Manifold

Shut up you knob

Daz

 

[Ian (Geforce)]

Re: Re: Re: Manifold

Yes dad.

 

[Tom]

Apart from melting your catalyst and maybe the lambda sensor... (I'm not kidding)

1) keeps engine bay temps down
2) hot exhaust is less dense than cold exhaust so you get better flow through the manifold

Couple of BHP at most but will improve the responsiveness of the engine.

After looking at an HGT in the metal, I'd say you have no hope at all of lagging the manifold with it on the car.

 

[Ian (Geforce)]

Re: Re: Manifold

Errr, how does putting tape on your manifold melt the catalyser? + possibly destroy the lambada sensor?

Ian.

 

[Tom]

Re: Re: Re: Manifold

Cos you are insulating the manifold, hence the exhaust gasses won't cool down as quickly and the lambda and cat will get chuffin hot

 

[Daz155HGT]

Re: Re: Re: Manifold

I'm not planning to do it...just one of those things i wanted to know.

Daz

 

[Ian (Geforce)]

Re: Re: Re: Re: Manifold

Riiiiiiiiiiiiight

So you gotta coat the whole maifold in tape to get this 'effect'?

More to the point, why would you want to do that?

Ian.

 

[Tom]

Re: Re: Re: Re: Re: Manifold

As I said:

1) reduces the temp in the engine bay as you are insulating the manifold (they can glow red when you really thrash it)

2) as the gasses are not cooling as fast, they flow quicker through the manifold. You get a bit more power and better throttle response.

I've done this to my MGB mostly cos the manifold is right under the carbs and it was boiling the petrol!

 

[Daz155HGT]

Re: Re: Re: Re: Manifold

*Gets out the camera ready for when Ian trys's to lag his manifold with masking tape*...

Daz

 

[Ian (Geforce)]

Re: Re: Re: Re: Manifold

Okay Tom, cheers for the info.

Hmmmmmmmmmmmmm

 

[Tom]

Re: Re: Re: Re: Manifold

I think Ian has his thick head on tonight

Its a cheap mod, does make a difference but on a cat'd car I'd really not bother. Certainly if you had a stainless manifold its worth it, they are alot thinner and REALLY heat things up under the bonet. Even just lagging the first 6" so as you don't run the risk of frying the cat will help no end.

Hows the in car PC? If I'd known you were planning one I'd have added you to the PSU group buy on talk audio. Too late.

Sleep for me!

 

[Ian (Geforce)]

Re: Re: Re: Re: Re: Manifold

Nah Tom, I getcha.

Just a bit curious why I've never heard of this before

Night

 

[Graham]

lagging the manifold as Tom said keeps the gases hotter for longer which means when they exit the head they dont slow down as fast therefore reducing back pressure and increasing the responsiveness of the engine. Of all the people ive known to have done this though, a few off the tipo forum, ive not known catalyst or lambda failiure as a result! it obviously depends on how close your cat and lambda are to the manifold I suppose. Got to be careul mind as there have been stories in past of bodged jobs where the lagging hasnt been securely attched and has caused engine bay fires!!

 

[Tom]

Re: Re: Manifold

It depends on the engine and the cams. The HGT is variable timing so you get longer duration at high revs which means the exhaust valves open earlier so the exhaust gasses have cooled less in the cylinder.

Its not a 100% you will melt something, its just you might.

 

[Ribzz]

Re: Re: Re: Manifold

Tom is right about the stainless manifolds glowing red!

If i hold the revs at 3500rpm on my bravo for about 2 mins the 4 branch glows cherry red! lol

not something I've made a habit of doing but its a nice party trick lol

 

[Tom]

Re: Re: Re: Re: Manifold

My MG does that too! I'd lag yours if I were you! Probably get you a bit more BHP too.

 

[Ian (Geforce)]

Re: Re: Re: Re: Re: Manifold

Hey Ribbz,

just out of curiosity, what if you held the revs at 6000ish for 2 mins? What would that do?

Ian.

 

[Ribzz]

Re: Re: Re: Re: Re: Re: Manifold

It would glow red Ian!?! lol

I might do that Tom, It looks sow nice and shiny though

good cheap way to gain a few more horses though hmmmmm