[Torbjorn968]

Good morning gentlemen and gentlewomen (was the womens day in Sweden yesterday so <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" /> )!



I would first like to thank Pete at RS Barn for patiently answearing my questions. Saving up for the engine mods have taken a bit longer than expected (running costs at the track is one reason). But when I take the plunge I am looking for a cost efficient route.



I have already made the misstake of buying a modified cylinder head. I say a misstake because reading on the subject I would think priorities goes this way:



- chip



- Airbox mod (done)



- exhaust and headers



- cams



- then the cylinderhead...



- remap on rolling road (no chip available for this chain of changes).



I thought this might be of general interrest so hence putting the question up on the forum rather than continuing calls to Pete, especially with my hearing disability making calls difficult (hearing aid does not fit into the headset...).



Some background: the car is mainly driven on the track which means that drivablity in an everyday context is less of a concern. Since I have the cylinder head I wish to do all changes which are prior to the head in importance.



To my questions:



- do you aggree on my proposal for priorities?



Given that you do this I have one main question after reading the threads on this forum:



- Pete reports substantial increases of power in the midrange in a thread changing headers/exhaust



http://www.968forums.com/index.php?showtop...&hl=dynojet



Does this mean I can go for a sharper (I hope my terminology is correct) cam than a "sportcam"?



Does sharper cams mean other expensive modifications (in which case I should stop where I do not need to invest furhter)?



Would omiting variocam together with the change of exhausts be a less expensive path than retaining the variocam? And perhaps more reliable?



http://www.968forums.com/index.php?showtopic=4708



I know Pete has not tried the non variocam engine yet, but just as an indicator of a suitable path for the day when I have collected enough commissions.... <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" />



Swedish tracks are generally rather small and twisty and you seldom go above fourth gear if that is any information in valuating the need for better torque in the midrange.



Best



TL

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[Mark]

I would think you are correct that exhaust and headers would be the next step. Variocam could be dumped on a race car for an aggressive race cam as well.

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[RS Barn]

I had to print T's reply to look at questions.

T had it right with order of mods

Chip

Airbox

exhaust/headers

cams

Cylinder head

The first 4 mods are documented and work well together. The cylinder head is a variable. I've tested several mods and find the minimal mod "Stage 2" works well for more flow and approx 5HP gain

Larger ports seem to diminish any power /torque gains until 6K or so.

I have a few secrets for extra power 6-10hp but don't want to publish now.

Pete

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[pazzer]

After speaking to a reputable porsche engine builder in the UK, his impression on heads is that the 968 head ports are to large to gain any significant horse's, designed to be turbo charged apparently, a good idea would be to source a 2.7 16 valve head and have the ports welded up and then re-machined smaller but the problem lies in how small, thats the question. After comparing two chips (wont disclose the makes) for obvious reasons, one has a lot more grunt at the lower rev range whereas the other benefits in the mid and slightly more at the high end of the revs, if you got a live map of the two chips characteristic's you would have a awesome chip with a smooth consistant power curve, this may well be my next step in the quest for a 280hp+ engine, any thoughts from anyone would be more than welcome! pazzer.

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[Ryan]

16 valve cars only came in 2 flavors as far as I know: 2.5 & 3.0 -I have one of each.

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