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Al71

What Is Best Carb For Draw Through Supercharged L-series

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Al71    0

Hi,

I currently have a SC14 supercharged L20b running a 32/36 webber but I am not happy with the way the mechanical secondry comes in.

Can anyone give me any guidance on what type of carb would be best for the draw through application that I am running?

On a seperate note, I would also appreciate any info on what cam to run with the supercharged setup. I got a cam done specifically for the application with from memory the lobe centres opened up a bit (I will have to check though) to suit supercharged(I was told this is what they need by my head specalist).

It seems to be only strong to 4500 then its a bit blah(good technical term hey), cam builder advised the cam grind should rev to 6500 or 7500 on a N/A engine with webbers.

I am sort of thinking this may be due to carb but any info/input would be greatly appreciated.

Thanks

Al

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+fveten    17
Anyone, Anyone, Anyone!

Buller!

I'm leaning towards a 2" SU at the moment.

Ive been playing around with a blow thru set up ATM.

http://datnet.org/FIA-510-series-Project-t....html&st=20.

Ive found the weber to be ok , but its mainly the ignition side of things that take abit of work.

Do you have any pics with your current set up ??

I'd lean towards a single DCOE set up personally, you can fine tune them alittle easier and get more out of them compared to a SU ??

What are you using for ignition ??

keep with the carb/turbo set up .. a little more old skool fun. B)

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+Baz    1

Hi,

I currently have a SC14 supercharged L20b running a 32/36 webber but I am not happy with the way the mechanical secondry comes in.

Can anyone give me any guidance on what type of carb would be best for the draw through application that I am running?

On a seperate note, I would also appreciate any info on what cam to run with the supercharged setup. I got a cam done specifically for the application with from memory the lobe centres opened up a bit (I will have to check though) to suit supercharged(I was told this is what they need by my head specalist).

It seems to be only strong to 4500 then its a bit blah(good technical term hey), cam builder advised the cam grind should rev to 6500 or 7500 on a N/A engine with webbers.

I am sort of thinking this may be due to carb but any info/input would be greatly appreciated.

Thanks

Al

/quote]

An IDF from twin carb 33 alfa is a go.

Easy to tune like dcoe, small chokes but you will be surpised at the performance.

Light throttle jetting & ignition are critical for good low down grunt & economy.

Use water injection.

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Al71    0
ignition?

I have the electronic ignition from a bluey, What needs to be done to it?

It's already good down low, its up higher in the rev range where I have the problem.

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+fveten    17
It's already good down low, its up higher in the rev range where I have the problem.

On my blow thru set up , i run the same Bluey elect dizzy and i get heaps of low end torque with the initial timing set high but it detonates when on full throttle under boost (11psi) , where it needs to retard. So i back the initial off and its a little sluggish off the mark, doesn't detonate up high, but im robbed of a heap of HP at the top end ..

Could play around with the springs alittle,by slowing the adv curve, but it still wont retard on boost.

Heap of initial is what i need and then to retard on boost, but after all the time and effort ( and dissapointment), with the stock dizzy, im seriously looking at the MSD 6BTW set-up http://www.msdignition.com/product.aspx?id=5859 .

This should work really well for my application. I want to run more boost.

Alternatively, i thought of running an engine management system from a Fuel Inj system and only running the ignition side ,so i could map the ignition curve to suit what i like, but to get a system to do that would still be in the same ball park as the MSD @ around $500 ish..

How much boost do you run ??

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+Baz    1
On my blow thru set up , i run the same Bluey elect dizzy and i get heaps of low end torque with the initial timing set high but it detonates when on full throttle under boost (11psi) , where it needs to retard. So i back the initial off and its a little sluggish off the mark, doesn't detonate up high, but im robbed of a heap of HP at the top end ..

Could play around with the springs alittle,by slowing the adv curve, but it still wont retard on boost.

Heap of initial is what i need and then to retard on boost, but after all the time and effort ( and dissapointment), with the stock dizzy, im seriously looking at the MSD 6BTW set-up http://www.msdignition.com/product.aspx?id=5859 .

This should work really well for my application. I want to run more boost.

Alternatively, i thought of running an engine management system from a Fuel Inj system and only running the ignition side ,so i could map the ignition curve to suit what i like, but to get a system to do that would still be in the same ball park as the MSD @ around $500 ish..

How much boost do you run ??

water injection is where its at, its worth 8 degrees extra advance.

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+Baz    1
water injection is where its at, its worth 8 degrees extra advance.

std cam reved to 8K, tho power dropped of at 7k in higher gears.

13 lbs boost SC14, keep it lean down low & higher advance will give gret torque at light thottle.

achieved 10k /litre generall daily stuff.

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Al71    0
On my blow thru set up , i run the same Bluey elect dizzy and i get heaps of low end torque with the initial timing set high but it detonates when on full throttle under boost (11psi) , where it needs to retard. So i back the initial off and its a little sluggish off the mark, doesn't detonate up high, but im robbed of a heap of HP at the top end ..

Could play around with the springs alittle,by slowing the adv curve, but it still wont retard on boost.

Heap of initial is what i need and then to retard on boost, but after all the time and effort ( and dissapointment), with the stock dizzy, im seriously looking at the MSD 6BTW set-up http://www.msdignition.com/product.aspx?id=5859 .

This should work really well for my application. I want to run more boost.

Alternatively, i thought of running an engine management system from a Fuel Inj system and only running the ignition side ,so i could map the ignition curve to suit what i like, but to get a system to do that would still be in the same ball park as the MSD @ around $500 ish..

How much boost do you run ??

I'm only running 5lb at the moment but am in the process of upping pulleys to get 10 max.

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Al71    0
On 9/26/2008 at 10:37 PM, Baz said:
Al71 said:

Hi,

 

I currently have a SC14 supercharged L20b running a 32/36 webber but I am not happy with the way the mechanical secondry comes in.

 

Can anyone give me any guidance on what type of carb would be best for the draw through application that I am running?

 

On a seperate note, I would also appreciate any info on what cam to run with the supercharged setup. I got a cam done specifically for the application with from memory the lobe centres opened up a bit (I will have to check though) to suit supercharged(I was told this is what they need by my head specalist).

 

It seems to be only strong to 4500 then its a bit blah(good technical term hey), cam builder advised the cam grind should rev to 6500 or 7500 on a N/A engine with webbers.

 

I am sort of thinking this may be due to carb but any info/input would be greatly appreciated.

 

Thanks

 

Al

 

 

/quote]

 

An IDF from twin carb 33 alfa is a go.

Easy to tune like dcoe, small chokes but you will be surpised at the performance.

Light throttle jetting & ignition are critical for good low down grunt & economy.

Use water injection.

What size so i find out there were different sizes at minumum they had 36's and 40's? and what sorts of jets are a good stating point?

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