Fao itb users

[Chip-mk1]

Bang on, and it's pretty obvious really - I don't see why these threads always turn into a boost vs itb debates as there's never a definitive answer. Other than pub talk

Its much like the recent threads on the RS2.

People were moaning about the torque figures not being as high as on 438 cammed cars etc, which is of course true, but it doesnt stop it being a fantastic modification.

Basically with an RS2 on an F4R and a set of 197 cams, it drives like its the worlds best 1800 engine bascially, 140lbft for the entire rev range and 200bhp at 7800rpm is fantastic fun to drive, it just feels so relentless and keen to rev etc. Sure it doesnt have the brief torquey midrange hump you get on a cammed motor but thats not always a bad thing as the problem with a brief surge in torque is that then when its over the car then feels flat after that. Where as if instead of high torque in the midrange and low torque at the topend, you have medium torque for the entire rev range it just feels relentless and is very rewarding to drive as it goes the same at any rpm so it doesnt feel flat anywhere at all compared to anywhere else.
But trying to explain that to people on here is a waste of time I have found, some of them just obsess over peak figures and cant understand that its only any good having torque if you have it for more than a few hundred rpm, and IMHO you have to drive one to appreciate it really, and even then peoples tastes are different and some will love the crazy way they rev and some will hate the fact they dont have that brief torque shove, it all depends on what you enjoy from an engine.

 

[Chip-mk1]

Chip what's your turbo mapped to at WOT out of interest?

On the old engine I had it at low 12s when I was using it for road use and knew I would only be on the throttle briefly at full throttle, but I ran it at high 10s and low 11s on track in order to keep the valve and piston temps down.
The difference between the two was quite noticeable, it felt a lot crisper in the low 12s, but I would strongly advise against anyone getting their car mapped like that if they had the same spec, you would melt it in no time if you hang it out up a big f-off hill in a high gear, but I mapped it to that knowing that I would drive it in a heat sympathetic way in the first place.

Now that I have forged internals I will run it at mid 11s all the time probably as the difference between that and low 12s is far smaller and it should be safe at that even for sustained use.

 

[SharkyUK]

Indeed mate, the thing I've found with ITB's is the more cars you read about them being done, the more they seem to break, i.e yours, sharkys, Ash's race car etc, maybe its just coincedence that the only cars I read about with ITB's are the above mentioned however it puts me off, has anyone fitted Itb's, had them mapped then never had to touch them again throughout the life of the car?

ITBS need general maintenance with balancing and cleaning once every few months really depending how much it's used. Sharky had a run of bad luck but the engine in his trophy was rough to start with. Which was overlooked by there tuner. I just like going through engines.

The lump that did a head gasket on mine recently was a scrap yard engine with some cams thrown in to boot. It's no basis to base your own purchase on lol.

^ Indeed - just to highlight that my engine really was in no condition to have had the work done initially and had I known I would have got everything sorted out first. However, I did not realise this, wasn't informed and the work still went ahead. This has probably not helped matters along with the run of bad luck. Hindsight is a wonderful thing. Still, despite the poor compression, poor filters, heavy-breathing, etc. the ITB's have been fantastic and I would recommend them to anyone. But, as already mentioned by Chip/Mike, you need to have realistic expectations and decide whether or not they offer the sort of driving experience you are after. For me it's a no-brainer. Forged, hi-comp NA all the way. Suits me, the way I drive and provides for maximum enjoyment (again, for me). It just means I have to be sensible, save hard and have a bit of money to one side to maintain the setup and/or have any work carried out.