Reliable Rolling Roads in the south west?

**matthewp1633** · 15th January 2019, 15:10

Nutron I am about to fit a front mount in prep for the turbo upgrade and I see most are using the intercooler that measures 140x300x65 but would a 180x300x65 cause any lag issues due to the larger size?

**Dog_Book** · 15th January 2019, 15:29

That increase is small so no, if I got my figures right in my thread in the petrol tuning you’ll see the fmic commonly used has a smaller volume than the standard IC anyway

**matthewp1633** · 15th January 2019, 21:55

Thanks Dog book

**Dog_Book** · 15th January 2019, 22:51

Originally Posted by matthewp1633

Thanks Dog book

Just did the maths the fmic you list is about a third of the size of a standard one anyway. https://www.vectra-c.com/forum/showt...ercooler-sizes
Nutron would be the best to sort the big maths out as as you can see the larger 2.8t has the same size thereabouts as the cdti but remember the petrol uses a lot less boost than the cdti let alone a mapped or hybrid one.

**nutron** · 16th January 2019, 09:34

The 41/58 will spool sooner than a 41.6/56.0 and should support the same boost or more because it has a large tip height. Lag in theory would be marginally higher but it is not noticeable at all. Don't confuse lag and threshold.

**matthewp1633** · 16th January 2019, 10:42

Hi Guys thanks for the replies so if I am reading correct the intercoolers used by most are 140x300x65 and will give a drop in intake temps mainly due to being better positioned into clean air flow. This is due to most mounting them under the bumper bar outside of the radiator/air con pack. The standard intercooler is bigger but is stuck between the radiator and air con rad meaning air flow is reduced and temp are higher due to that.

I plan on fitting an intercooler from ebay measuring 180x300x65 and I will remove the standard intercooler and push back the air con rad to free up room. I may also need to modify the bumper bar to allow for the increase in hight on the intercooler I am using. Thanks Nutron for the pointers and I am more interested in usable power over a wider band than big numbers and a short power band. I understand that lag is the time between when you open the throttle until the power starts to deliver. The threshold being the rpm at which the turbo reaches the point that it starts to deliver boost.

**Dog_Book** · 16th January 2019, 12:45

Got it in one, have a look for the pics how I fitted mine might be in the how2 was perfect

**matthewp1633** · 16th January 2019, 16:16

Hi Dog Book yes yours is still there and I did read it so thanks for that, did you get any improvement power wise with just the intercooler as I remember fitting one to my tomcat years ago and the improvement was noticeable?

**Dog_Book** · 16th January 2019, 16:33

Originally Posted by matthewp1633

Hi Dog Book yes yours is still there and I did read it so thanks for that, did you get any improvement power wise with just the intercooler as I remember fitting one to my tomcat years ago and the improvement was noticeable?

Not peak power but the cooler air must have helped give a reliable output, plus it’s better than the poor standard IC and the car has just been broken and the fmic and the pipework is all coming off to go on another car.

The best boost pipes are Fluro lined but cost a bit more