Cylinder heads: Having had a crash course explanation of cylinder head modding from Bill Blydenstein, and seen various bits of high spec kit over the years, I'd say most of the clever stuff is PRECISION machining around the valve seats and throat area. You could probably get a few BHP at home with the Dremel, but at least 50% of the power gains need specialised precision machines - e.g. multi angled valve seats, bored out valve throats, chamfered valve guide ends, etc. I used to work around the land rover engines machine shop... Most of the power gains are about removing the extra metal that mass manufacturers leave on to cope with the stack up of the different tolerances on the cylinder head - so with a precision machining job, for a one off, you can potentially remove quite a lot of spare metal. The end result is that the valve looks like it's hanging on the end of the seat by its fingernails, as there's no tolerance left. Insurance strips: If your engine looks obviously modified you need to declare it - e.g. a 16v in a driver. Non standard air filters, Bright red engine blocks are all asking for trouble. I've never had a mate who had his engine stripped by the insurance though... if it's obviously not standard, they don't need to, but if you're reasonably subtle they won't notice, or maybe just won't be bothered, particularly as most insurance companies use independent assessors that don't actually work for them. If you're after a GTI cam and head, I'll have one for sale shortly - 4 weeks ish. With a Mk2 GTi head you need to block up the injector holes if you're going to use a carb, or single point injection. Valve sizes on the GTi are 40 inlet and 33 exhaust (Mk2 and Mk3). Not sure about the 1.8 driver head. If they're close, or the same, it might be worth modding the existing head as a cheap option. For cylinder heads, try www.blydenstein.co.uk and help a top bloke out in his old age - the fact that he's built engines that won world championship rallies could also be a factor in the decision. Edited by: mikehorsb
Worked ok in my last one, and the last 7 i did for customers The only time you get problems is if you try to use the original Pierburg Carb, which are sh!te at the best of times, but if you use a Weber replacement(along with a quick and easy mod to the inlet manifold), there are no problems,the last one i did 4wks ago was on the rollers today, and made 128bhp@5450rpm and 115lb/ft@4750! Can't be that pooe! I agree, a flowed head would be better, as it would on any engine, but good results can be had with a std one too, its all down to the setting up Mike Edited by: lowrider
My Mark 2 Driver insurance has just been renewed, it is a 2 litre TSR carb engine, lowered, uprated brakes, exhaust back box and I paid 395 TPFT with 2Y NCB. Chris Knott insurance. They quoted me 500 for a standard16V Jetta GTi. So, not true about hammering you with the insurance. Try Chris Knott or Adrian Flux. Steve
