Hi all, I have a '91 GTI 8v and am considering doing some work on the engine to give it a bit more go. I've had a bit of a look on the net at heads and I thought something like the TSR pack C head with the 35mm exhaust valves would be the one to go for. Is this the head to go for? Your thoughts on it would be appreciated. Also is 600 the going rate for this kind of work, as that is what TSR's head is priced at. I would be planning on using the standard 1800 block to start with whilst saving to buy a 2.0 block. Would the gains still be noticeable with the 1800 block? Thanks, Osprey
would be a lot cheaper to sell the whole car and buy a gti 16v. or put a second hand 16v engine in. not sure of the cost, but it'd be less than 600 i'm sure.
An ABF 2L 16v mk3 motor is relatively straightforward into a mk2 digi & can be done for circa 750 all in IMO. If you are sticking to 8 valves...the pack C head is the one to go for (with a hotter cam)
You can get equal heads for less than 600 if you know where to look for them. Tuning an 8v is very expensive to get good power (sure Chris will agree) but it can be done (keeping the peace bit over ). What are you looking to end up with?
Why is everyones answer to an 8v tuning question 'stick a 16v in it'? If I wanted a 16v I would bought one in the first place. Having driven both I prefer my 8v. But thats just my opinion.
I agree Tub VERY expensive to get circa 160BHP.. An ABF 2l 16v conversion should give you this as a starting point..
Mouth shut so as not to cause offence... But i'll race your 8v and not even rev above 6k -- oops... here it goes!
Thanks for the replies. I'm not gonna get involved in the 8v vs 16v debate, i know that a 16v is quicker than my car and i'm fine with that! I don't want to get another car, i have mine the way i like it and it is immaculate, even if i do say so myself! I'm not looking for it to be seriously fast (160-170bhp) but i would like it to be on a par with a valver, so what do you reckon i'd be best doing? Headwork, a cam and an exhaust? The mk3 16v transplant does sound interesting though, is it more or less just plug and play seen as they both have digifant or would i need to change the looms, fusebox etc? Cheers, Osprey
I nearly forgot, Tubthumped...where should i look to get the head done cheaper if I decide to go that route? Cheers
I'm not disputing that the 16v is quicker, (especialy given that my car is weighed down with 1/2 tonne of ICE) I just prefer the 8v to drive around town.
is there anyone here that has an 8v that has over 180 bhp or is it impossible to get that from an 8v also why do the extra valves give it so much more just curious is it more fueling?
dirtydubber, i'm not havin a dig at you mate. I love my 8v too and I think it's a great car. Just after a bit more power. I wouldn't like it any more if it was a 16v because i've got my car how i like it and i don't want to change it appearance or body wise. Just looking for whats best and cheapest to make it closer to 16v performance.
My current 8v spec is a 1.9 TRS re-bore, with a TSR pack-A head, TSR 102 fast road cam, K&N panel filter and full stainless 2" exaust. TSR recon on it giving 140 bhp @ flywheel (I will get it set up on the rollers in the next few weeks and see) A pack C or D head will up the overall power a bit but will loose a bit of torque. I am well happy with it and it WILL keep up with a MKIII 16v
Pack C or D heads make a LOT of difference! You only have to look at the old Slick 50 racers making 165BHP from an 1800 8v & stock injection. The los of low down torque is negligible & is dependant on how hot you go with the cam.. The head is the key to making good power in any engine. Improving the flow with bigger valves makes an 8v much more revvy & torquey from 3K revs up & will keep pulling all the way to the limiter..
If you already have a head 600 just for headwork is too much. Find yourself a local engineer, word of mouth. Someone who has done it well before rather than someone who "can do it". I have a local who all the autocross boys use for engineering work. He has a sectioned 8v head that he cut through the valve guides so he could see just how close to get to the water/oil channels when p&p'ing. Rough extimate for a big valve head with new seats and rough porting - 250-300. You can polish the ports yourself once someone who knows has done the tricky stuff. 40 for a dremel. Pick up a 285 piper cam for 100-120 and you have a couple of hundred quid to play with! Off the shelf packs are expensive easy options. I they were that good all racers would be using them.
the 16v valve is more powerful purely because it has greater valve area. i know theres some inadequacy with the vw 1.8 16v that it makes less torque than the 8v up to XXXX rpm, but generally a 16v engine with good induction and head design will make more power and more torque over the entire rev range. on a slightly seperate note, if you had an 8v head with say 20 square centimetres of valve area, and a 16v with 2 smaller valves equalling 20 square centimetres, the 16v would still outflow the 8v because its got more valve FLOW area.
Generally, early 16v motors loose out on low end torque compared to their 8v counterparts. Yours may do well compared to its 8v vauxhall equivalent, but don't forget it has; closed loop ignition control, mass air flow measurment and sequential injection. You cannot make a direct comparison (assuming you were). Valve "flow" area is proportional to total valve(s) circumference. Mark
