peterpeter

[peterpeter]

Dear Guys and Gals,

I have a 2 litre pinto in a seiw . apparently producing 138 bhp at the wheels.

It only has twin 40 carbs on board, and rather small ( 1inch ) air filters. ....How much extra power would switching to twin 45s (or indeed is there anything better?) and a larger kick ass air filter , get me??

Is there anything else relativley simple I could do to get more power??

Any guesses welcome...

[Neil Purdie]

My car has a 1700 X-flow in it, with DHLA40's.  tiewraped on the ends of the rampipes are short sock type filters ( they are shorter than the recomended length ).

On a recent rolling road set up, we found an extra 8 BHP with the filters removed, total 95 at the wheels.  When I have the time, a large filter and hole in the bonnet will be a priority.

1.  Its not the size of the carbs, but the size of the choke in the carb.  If your engine is in standard tune then 40's can still house a choke big enough for the engines needs.  If the engine is modified then the carbs may be too small to house a choke large enough to let your engine breathe.

ie for peak power @

5500 RPM then 40's with 34mm choke

6000 RPM then 40/45 with 36mm chokes ( the largest a 40 can take )

6500 RPM then 45's with 38mm chokes

2.  Get the car on a RR and try with and without the filters, this will let you see if the filters are restricting the engine.

Many threads have been posted about holes in bonnets and intake temps, with the general feeling being a filter sticking out the bonnet will give a lower intake temp and thus more power.

[kennedyj]

peterpeter,

138 BHP at the wheels - I'm impressed.  This means you must be getting around 170 BHP at the Pinto flywheel on twin 40's. If it were me I would leave well alone, my Pinto with trick cam, trick valves, flowed head and twin 45's doesn't give me that much power.

-JohnK.

[Liam]

Whats been done to it to get that sort of power? I have a standard pinto on 45's that gives 100.3 at the wheels and am contemplating a road/rally Kent cam as the next stage which I am informed would add about 20. Anything else presumably means major surgery/bag of gold.