GT6 air filter

[Acole]

Hi, I am looking to replace the original air filter on my GT6 with either pancake filters (Such as K&N filters) or trumpet filters. I was wondering if anyone has any advice which are better and advice which brands to use. The reason for the change are aesthetics and ideally give a nicer sound. Forgive me if this upsets the purists. 
Thanks, Andy

[dougbgt6]

Hi Andy,

I'm not a purist, but the fact is the original filter set up works better than pancakes. What your carbs want is cold air ducted from the radiator cowl, not hot air from under the bonnet. But if you're determined!   Be aware that if you go for pancakes different needles are required, these are available from the usual suspects.  

Doug

[Acole]

Thanks Doug, and here was me thinking this would be a quick customisation to my GT6 to be done during lockdown!

[Iain T]

Andy, 

I had original filters on my vitesse then changed to K&N's. However on testing both on a rolling road I was surprised to see no difference on power and torque using the pancakes even with fettled needles. I think any extra vroom is in only in perception not actual performance. I will be changing mine back to the normal air box with external filter. 

[Clive]

If you want an improvement, you can use K+N filter elements inside the original airbox,along with a "stub stack" which smooths and increases airflow.

Avoid the trumpets with a gauze fitted, they reduce airflow and still allow fine grit into the engine, plus warm (less dense) air.

Iain is on the money, you can use the airbox (ideally with stub stacks) and then tubes with an external K+N cone.

 

My spitfire (not at all std) I recently made an airbox with 100mm feed tube and a fat K+N. Rated to 500bhp! (my car won't trouble that) but the cold air feed meant I had to alter fuelling, and the other advantage is it is quieter!

[dougbgt6]

I guess the change of needles to get the same performance means you're using more fuel? But, hey! The price of petrol is now so low I'm thinking of buying Jerry cans in Rimmer's sale. 

Doug

[Colin Lindsay]

1 minute ago, dougbgt6 said:

I guess the change of needles to get the same performance means you're using more fuel? But, hey! The price of petrol is now so low I'm thinking of buying Jerry cans in Rimmer's sale. 

Doug

I'm thinking of buying an old home heating oil tank... cheaper locally for a 1200 litre version than for two Rimmers jerry cans... add an old vintage petrol pump and happy days.

 

[dougbgt6]

My brother tells me you're only allowed 20 litres in your garage and what with the Corona police I'm not going to chance it. I remember the petrol crisis when we were all allocated coupons, my dad had 8 x 20 litre Jerry cans in the garage.   

Why are they called Jerry cans?

Doug

[Clive]

17 minutes ago, dougbgt6 said:

I guess the change of needles to get the same performance means you're using more fuel? But, hey! The price of petrol is now so low I'm thinking of buying Jerry cans in Rimmer's sale. 

Doug

More air, more fuel=more power. That's the name of the game. (but mine is EFI, so more watch the AFR gauge, a tap of the keyboard and job done)

Fuelling at cruise is rarely affected....

[Nigel Clark]

32 minutes ago, clive said:

If you want an improvement, you can use K+N filter elements inside the original airbox,along with a "stub stack" which smooths and increases airflow.

Avoid the trumpets with a gauze fitted, they reduce airflow and still allow fine grit into the engine, plus warm (less dense) air.

Iain is on the money, you can use the airbox (ideally with stub stacks) and then tubes with an external K+N cone.

 

My spitfire (not at all std) I recently made an airbox with 100mm feed tube and a fat K+N. Rated to 500bhp! (my car won't trouble that) but the cold air feed meant I had to alter fuelling, and the other advantage is it is quieter!

Or...

I made an airbox with K&N cone filter well forward to suck cold air, and stub stacks on the carb mouths inside the box.

The engine will run better when sucking cold air from ahead of the radiator, as the original filter did. This project would use up more lockdown time than fitting K&N pancakes!

 

Nigel

[trigolf]

27 minutes ago, dougbgt6 said:

My brother tells me you're only allowed 20 litres in your garage and what with the Corona police I'm not going to chance it. I remember the petrol crisis when we were all allocated coupons, my dad had 8 x 20 litre Jerry cans in the garage.   

Why are they called Jerry cans?

Doug

Doug

They are called Jerry cans because that's who designed them. During WW2 our Desert Rats came across them during battles with the Afrika Corps and found that they were a far superior design to the crappy square petrol cans that our poor guys were using. The Brit one's were very prone to splitting too and no where near as strong the Jerry Can. So our guys used them whenever they could.

Gav

[Iain T]

I bought these from Rimmers, they are stub stacks for SU HS4's. I just eased out the fixing holes and machined a slot for the air piston and voila better air flow. 

[Iain T]

Nigel, 

I'm going to do the same setup but modify a standard airbox. We'll that's plan A, plan B which may well be easier is to make a new one like yours. 

Iain 

[Nigel Clark]

8 minutes ago, Iain T said:

Nigel, 

I'm going to do the same setup but modify a standard airbox. We'll that's plan A, plan B which may well be easier is to make a new one like yours. 

Iain 

I reckon starting from scratch to make a new air box will be easier than trying to graft a filter on the front of the old air box.

Mind you, I had no choice but to design my own in order to fit the short dashpot HS6 SU carbs.

Nigel

[JohnD]

21 minutes ago, trigolf said:

Doug

They are called Jerry cans because that's who designed them. During WW2 our Desert Rats came across them during battles with the Afrika Corps and found that they were a far superior design to the crappy square petrol cans that our poor guys were using. The Brit one's were very prone to splitting too and no where near as strong the Jerry Can. So our guys used them whenever they could.

Gav

Absolutely!   Also, you may have noticed that the three handles across the top mean that:

You can carry one well balanced in the hand, or one in each hand (middle handle)

You can carry two together in one hand (side handles)

Or carry one between two (both side handles)

The cap is a positive seal, and pours well,

and, you can get spouts to make them pour even better!   That stores in a clip on the top: https://www.expedition-equipment.com/product/jerry-can-spout-clip-on-kit/

 

[thescrapman]

5 hours ago, dougbgt6 said:

My brother tells me you're only allowed 20 litres in your garage and what with the Corona police I'm not going to chance it. I remember the petrol crisis when we were all allocated coupons, my dad had 8 x 20 litre Jerry cans in the garage.   

Why are they called Jerry cans?

Doug

There is no limit to how full you can have the tank of the car, so if you have 10 cars in the garage (and who doesn't) you can store at least 100 gallons. 

[Colin Lindsay]

12 hours ago, thescrapman said:

There is no limit to how full you can have the tank of the car, so if you have 10 cars in the garage (and who doesn't) you can store at least 100 gallons. 

I've already topped the GT6 and the TR7 up to the brim, and then keep siphoning it out again for the lawnmower... the daughter is still working night and day - literally - but at present she can fill up at some of those unmanned petrol stations so I don't see it being a problem for a time. I've driven less than ten miles in the last ten days so with the diesel showing a range of 560 miles that should be enough to last until 2022. 

Apologies to Andy who started the thread, I'll steer back again and agree with the others that I had K&N air filters on the GT6 simply because everyone else was doing it, but then went back to a standard air filter box and original filters. I've just realised that I'm probably running on the same needles, though; must check later today.

[Pete Lewis]

on the VIT6 i added stub stacks inside the orginal filter with a bit of careful cutting  needs the crush tubes shortening

just an  out the box  idea if you feel like inspiration over the next few weeks  

pete

[dave.vitesse]

Opening up the air flow generally means you lose some low RPM torque, but increase the top end. The stack help maintain the low RPM without restricting the top end.

The air cleaner set-up on my Vitesse is standard. Though it has gone through may changes over the years.

On Mk1/2 GT6/Vitesse fitted with free low air cleaners the standard needles with stronger springs work well. The Mk3 GT6 has a limited adjustment on the mixture and a lack of suitable richer needles, so not so easy to get right.

But my TR7 uses K & N's with stacks, richer needles and a better exhaust, Standard Stainless Steel, which would well, it wakes the engine up. As it's a crossflow engine there is no exhaust under the carbs giving heat problems and the standard air cleaner appears to be very restricted.

 

[Graham C]

The reason for the restriction on storage is the quality of containers, people are stupid. Cars are fitted with approved storage tanks so are deemed safe.

When we had those strikes which affected petrol supply, a taxi driver stored petrol in a wheelie bin in his house, which then dissolved and contaminated the soil under his terrace house and those next door.

Graham

 

[thescrapman]

I reckon you could keep diesel in a wheeley bin..... mmmmmmm....

[Colin Lindsay]

Wheeley?