affordable performance & tuning pitfalls - my opinions!

[mk3tdi]

(day off work with the snow  ;D found your decent forum & just joined)

Well, firstly I am a former diesel-hater turned TDi lover, imho the Mk3 TDi is the pick of all the Golf bunch :o <cue differences of opinion>  ;)

The Mk4 has more safety features, can anyone else think of any other improvements - I can't! I prefer Mk3 styling, they're better value, lighter and handle better, without over-servoed brakes & steering - no contest!

The Mk2 & Mk 1 are great cars, great handling and were still light enough to perform brilliantly with minimal power. Happy days  8)

However, for looks, safety, comfort and style the Mk3 is the best compromise and is under-rated by non-VeeDub petrolheads  >:(

I am not referring to the GL TDi in stock form mind!

Mine is on 15" VW Sport alloys & 195/50s, the optimum. Larger wheels are great if you like the looks (up to 16" I'd agree) but do nothing for the handling and have a detrimental effect on unsprung weight. As for the guy who has lowered on 14" wheels - why mate  ??? :)

Btw, whilst the Toyo Proxes are excellent tyres, Yokohama AVS are the best performers though. Costwise I get mine trade price but the local tyreplace is ?52 fitted.

Lowering is a diminishing returns game. If you lower mainly for looks, I would argue that you are more poser than driver, which is fine by me, but not for me! But it would never improve the ride/handling to lower more than 40mm, in fact 20-30mm is far better imho, and causes less unnecessary stress on the car and adverse handling problems.

The TDi engine is the most easily tuned - from 90 to 125bhp properly for around ?350 without chipping, then 150bhp+ with a chip (around another ?350 for a decent chip properly mapped to that car). All this is without adverse effects on performance and economy which is still good when thrashed with 50mpg+ possible on a run.

I just turned 25 so appreciate the cost of insurance for young drivers.
Insurance will increase if you declare all the mods, but otherwise is a hell of a lot lower than any bog-standard GTI. Bear in mind you should declare everything, but since changing the injector nozzles and chip are, for all practical purposes, both visually and diagnostically undectable - few people ever bother!

On sticky tyres with decent upgraded pads and discs you will outstop most cars and never induce fade in road driving. I use Tarox Frenitalia G88s (grooved not drilled - another opinion ;) ) and Greenstuff pads, cost me ?180 inc fiitting & performance brake fluid - best money I ever spent on a car. Rear discs are simply not a significant factor in braking performance on the Golf - leave the drums on and spend your hard-earned elsewhere!

My TDi generates more torque than a VR6 & is light enough to avoid the weighty-nosed understeer of the venerable six-pot. I do prefer the noise of petrol cars of course (I'm not mad!) but you love the TDi for other reasons.

But hey, if you really want a noise/driving fix, spend 3 or 4 grand on a Westfield on Carbs and enjoy a car that will outhandle any Golf, cost pennies to insure and go round a track all day without wearing it's tyres and pads... nuff said?  :P

However, these are my opinions and if cost (and high mileage) were not an issue I would run a petrol car too. I can't wait to drive the Mk5 Tdi, I hope the Golf magic just skipped a generation! I have learned from fellow TDi-freaks and the excellent TDiClub.Com site, I don't claim any authority.

So if anyone can help me I am at a suspension crossroads. My car is running on stock dampers and Eibach Pro-kit springs (as i bought it) a combo I'm unhappy with. I suspect the stock dampers with the Eibachs are the problem - can't think what the last owner was thinking of!

Can anyone advise on dampers? I cannot stomach large drops in height nor a hard ride. I just want firmer (progressive) dampers than stock.

I was told by DubSport that: H&R, AVO and Spax are all too hard, a set of Bilsteins at ?120 is better but Koni top-adjustables at ?250 would be best. Mind you there are different models and prices for each brand, so first-hand info is what I badly need.

I guess I could always replace mine with a coilover then sell the Eibachs. Anyone know any combos that firms everything up without being too stiff?

Also, I'll probably add firmer anti-roll bars when funds permit. Poly bushes would depend on how firm it gets already.

Look forward to your replies!  :D :P ;)

Ollie

[golfvr6]

how do you get from 90 to 125bhp without a chip?

[mk3tdi]

firstly, understand chips can only do 2 things:
1) alter the injection timing
2) increase turbo boost pressure
due to some good old over-engineering on volkswagens part these can both be done safely - to a point! But neither can be increased indefinitely without blowing up the engine or affecting durability. There is an optimal level for each, depending on other mods and engine factors.

No, the way to increase power without a chip is the same way VW did on it's rally-winning TDi, increasing fuel delivery through modified injectors. PowerPlus 520 nozzles can be swapped for the stock nozzles by any diesel workshop. More fuel = more power. However, you will then want more air, and would be useful to lower the exhaust temperature...

How? Panel filter is a good start, also cleaning out the intercooler and fitting a vent for it. Then exhaust mods to reduce back pressure and exhaust temp, which also allows the turbo to spin up more easily.

Hope this helps  

[golfvr6]

Yeah mate, i think you are be a optimistic with your power quoted.

[mk3tdi]

Fair point mate but you are wrong. Yes there are many "optimistic" BHP claims that simply don't hold out, commonly for petrol cars    "Power Costs Money" -  How much did you spend?

I realised this reading the review of the Turbo Techniks Elise, currently EVO favourite tuned Elise, supposedly good value - that was ?3500 for a 43bhp increase!

But it's simply the case that forced induction engines are easier and cheaper to tune, (I'd imagine this would be true tuning from 150bhp to 225bhp with the 1.8T versus the 2.016v???) but more so for the VW 90bhp diesels which were vastly over-engineered and detuned in the first place. Bear in mind that the Golf that won Rallies were stock 90bhp TDi engines tuned to 190bhp... I believe the Aussie Touring Car Championships were won by a Seat with a tuned stock TDi engine!
 
But anyway, my friend's car is dyno-tested at 150bhp and 190bhp depending on which chip he is running (for road or track). If you want evidence look on the TDiClub.Com forums.

I tell you what, I could be wrong, but when development on my car is finished it will go on the rolling road. I can put up the results along with a breakdown of everything spent on it, if you really want.

Cheers for the vote of confidence  

Ollie

[golfvr6]

If you want mate, i'm not bothered as i've already got 180bhp under the bonnet  

[golfvr6]

Out of interest, are you doing the upgrades yourself?
You did actually say that you could get another 35bhp without chipping your car, now thats what i thought was a bit optimistic!

[mk3tdi]

forgive me if i replied already (degenerative memory) in answer to 35bhp increase possible on a stock 90bhp TDi without chipping:

modified injectors (ie. replacement nozzles) which I already have...
coupled with secondary/larger intercooler (this is what I am likely to do next) should give a lot more than 35bhp increase. Should be cheaper than a rechip and again I'll have to prove how much on a rolling road but it's all tried and tested stuff.

I may still chip later to increase boost but we'll see... will keep you posted on developments!