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Eddie · 20-05-12, 12:34 PM

Steve had the bubble remapped and smoothed out a lot of the power, in fact, he done a fair amount of road mapping himself. When G built Steve’s bubble and had it mapped at PTS it was an unknown assortment of parts, the inlet was OE but PTS where unable to find an auxiliary to run the VIS system so mapped around them (left wide open), the exhaust manifold was made by Tony Law and in my opinion didn’t really suite the KV6 for making good power, just a very good OE replacement. Steve then insisted G use his very expensive back box and induction kit in the build, this limited power a lot (at the time). The car felt quick as it was in a lighter shell but in reality it went down POD in a 15 second quarter.
As I said in my last post, it’s OK to bolt on cams and exhaust manifolds which are designed for a stock KV6, you know what to expect, good punch of mid range with average top end gains. To increase on this you are looking at tuning the complete system from inlet to down pipe, remember, the engine is only an air pump, the more air you put “through” it (notice I never said “in”) the more power you’ll gain.
NASP tuning relies on flow, give an engine a massive gulp of air it will only digest what it’s internal components will allow (unless forced induction), increase the size of its throat (cams and ports) then it will swallow more, then increase its ability to digest that air (lungs) combination of compression ratio and exhaust manifold design it will consume the air with a mix of fuel and produce some power. Simplified yes, but NASP tuning rules are fairly basic, you can put in the same volume of air through 2 KV6’s and make each one produce its power in completely different ways, look at what happens when you replace the OE airbox for an induction kit, it flows more, this will only work up to a given point before the OE system will choke, some engine designs are very good from the factory and will have bolt on modification that promote power in different ways, low end with midrange punch or a lot or top end power, all down to the design of the parts installed.
IMO, Steve’s engine will maximise the potential of the exhaust manifold fitted, JS I believe, these have been proven to make good midrange power compared to say the H&S tuned system, there is a lot of research in manifold design’s for a good reason, what I do see is plenty of potential for development in the future, the induction and, injectors and management have been nailed, with increased compression ratio (pistons) with a cam profile and manifold matched for flow characteristics it will be interesting to see the results.

20-05-12, 12:34 PM	#128
Eddie Member Join Date: Oct 2008 Location: France Posts: 51	Steve had the bubble remapped and smoothed out a lot of the power, in fact, he done a fair amount of road mapping himself. When G built Steve’s bubble and had it mapped at PTS it was an unknown assortment of parts, the inlet was OE but PTS where unable to find an auxiliary to run the VIS system so mapped around them (left wide open), the exhaust manifold was made by Tony Law and in my opinion didn’t really suite the KV6 for making good power, just a very good OE replacement. Steve then insisted G use his very expensive back box and induction kit in the build, this limited power a lot (at the time). The car felt quick as it was in a lighter shell but in reality it went down POD in a 15 second quarter. As I said in my last post, it’s OK to bolt on cams and exhaust manifolds which are designed for a stock KV6, you know what to expect, good punch of mid range with average top end gains. To increase on this you are looking at tuning the complete system from inlet to down pipe, remember, the engine is only an air pump, the more air you put “through” it (notice I never said “in”) the more power you’ll gain. NASP tuning relies on flow, give an engine a massive gulp of air it will only digest what it’s internal components will allow (unless forced induction), increase the size of its throat (cams and ports) then it will swallow more, then increase its ability to digest that air (lungs) combination of compression ratio and exhaust manifold design it will consume the air with a mix of fuel and produce some power. Simplified yes, but NASP tuning rules are fairly basic, you can put in the same volume of air through 2 KV6’s and make each one produce its power in completely different ways, look at what happens when you replace the OE airbox for an induction kit, it flows more, this will only work up to a given point before the OE system will choke, some engine designs are very good from the factory and will have bolt on modification that promote power in different ways, low end with midrange punch or a lot or top end power, all down to the design of the parts installed. IMO, Steve’s engine will maximise the potential of the exhaust manifold fitted, JS I believe, these have been proven to make good midrange power compared to say the H&S tuned system, there is a lot of research in manifold design’s for a good reason, what I do see is plenty of potential for development in the future, the induction and, injectors and management have been nailed, with increased compression ratio (pistons) with a cam profile and manifold matched for flow characteristics it will be interesting to see the results.