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Streetable 3.8


Vehicle Information: Model: 993 C2S; Year: 1998; Body Type: Coupe; Total Mileage: 41,000;

As you have been kind enough to correspond in the past, I have a new question. I own a 1998 C2S. The C2S engine was converted to a 3.8, with an RS Clutch, mechanical rockers/lifters, more aggressive cams, updated ECU and B&B headers and exhaust before my purchase. I bought the car with 37,000 miles and it now has 41,000. Shortly after purchasing, the car's alternator pulley was updated (updated design 99310626801) at the suggestion of the shop that inspected it post purchase. I had the car tested both before and after purchasingboth shops gave it great reviews, and other than the prepurchase maintenance and a new battery and updated pulley after purchase, the car was in great shape. I drive the car on a daily basis and use it for Street purposes only. Within a couple hundred miles, however, the CEL began intermittently coming on registering a misfire across most or all cylinders (62, 54, 55, etc.). At first, I thought that it might have been bad fuel but the problem persisted and became more regular. I had it checked (PS-II tested) several times by Porsche shop, they turned off the light and told me it was not a problem. But it has persisted.The valve chatter also sounded progressively louder to me--especially in the 1st and 2nd gear after the car warmed up. That, I assumed was the result of the mechanical rockers and perhaps the need for a valve job. As a result, I had the valves adjusted, the spark plugs changed (they were o.k. but since the exhaust system was off to adjust the valves had them replaced), and the distributors, belts, alternator belts and wires checked. I also had the secondary distributor belt checked, the 30,000 mile service redone (1st time by me) and the car test driven. The car runs very well, especially at higher speeds and idles fairly smoothly (there is some minor loping) There is some slight rattling or pinging in lower gears some times when you back off accelerationI have run Techron and BG44k several times to make sure no deposit build up causing thisand a ticking sound from the passenger side of the engine. After completing this work, the lifters/valves were still louder after warm up in the lower gears and every 22 miles or so of interstate driving, the Check Engine Light still comes on. (Will come on sooner if you drive in traffic using the lower gears.) As a result, I had the engine retested. Valve clearances are correct. Apparently, there is some lateral play in the solid rockers causing some noise and the compression of the cylinders is very highon leak down, all cylinders checked out at 350 psi cold. Also, I was told that the valve covers are plastic which allows for more lifter and valve sound to escape I have been told to run octane booster given the higher compression. There may be a worn valve guide on the passenger side of the engine but no oil burning and no codes regarding SAI. The car is not ready for valve job.Mechanic No 1(25 years of experience) says the car has a track engine set up although shows no signs of race wear or misuse. He says the engine is solid, has no leaks and is sound. He advises to forget the CEL as long as it shows just misfirethinks it is a software issue and could only be fixed through a remapping/reflashing of the software, and use octane booster. He says enjoy driving the car, the noise is nothing to worry about. Consulted Mechanic 2 (30 years of experience) who lectured me on the crime of modifying Porsches, said that he could not help since the car was modified, and instructed me to sell the car and buy an unmodified one because the car will never be streetable.Questions:1.I have read that 3.8 conversions are common and did not think they ruined the 993. If this conversion is common, why cant this engine be made streetablemeaning reliable and able to function without too much noise, run on 93 octane gas, and without the CEL light coming on always; other than the light and mechanical rocker noise, the car drives well;2.Can the lateral play in the solid rockers be fixed or adjusted during a top end job to reduce the sound (possibly install aluminum valve covers as engine tray is already removed?), 3.Can the car be returned to hydraulic lifters to avoid the valve adjustments if the cams are replacedassuming they are too aggressive? Or am I stuck with the present set up. Are mechanical rockers when working well still more audible in lower gears?4.Are there reputable shops in the Virginia/East Coast area that can detune the engine or remap the software to make the car streetable at the time I do a top end job; how do I tell what octane my car is programmed for? -or am I stuck due to high compression and need to look for a stock engine/ecu replacement to swap out with or sell the carseems drastic? 5.Who would you recommend (anywhere) for consulting to solve these issues.6.What other options do I have long term to have a reliable Porsche.Thank you for your time and consideration.

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