4" Downpipe & Dual 3" From Downpipe Exhaust!

[skeet94]

Hi all,

I've been looking at doing some power mods on the car for some time...due to some other things getting in the way it had to be put on the back burner...until now!

Back in January I'd been in touch with Hayward & Scott about a custom 4" straight turbo-back exhaust system. I was told that they were fully booked till mid Feb...but by then I'd already "blown" the money on other stuff - so booked the car in for Tuesday 24th March just gone.

Confirmed with Ian C (great guy!) who advised that it'd take approximately a week to get the bends, etc made and fit it all on. Drove up to Basildon on Tuesday morning and found it Hayward & Scott with no problems. Soon as I parked up there was a Mk2 N registration Ford Escort 1600. This car was immaculate ... along with a few other tube chassis cars sitting up on the lifts. Being impressed by the cars they had on hand at 7:40am (before business hours) I dad a word with Ian, with whom I'd already discussed the requirements via email, and was advised that a 4" system would hang "too low" so instead should do a 4" downpipe and have two 2.5" pipes coming back from the muffler back - agreed and discussed cost, etc. On the way back I realised that a dual 2.5" pipe setup would cause some "restrictions" compared to a full 4" system - did some maths, had a few words with some knowledgeable guys about volume, flow, etc and decided to change it a bit.

Called up Ian, advised if it would be possible for a 4" downpipe going into a pair of 3" pipes from muffler back - was told it would cause no issues with clearance and that it'd cost £100 more than originally quoted.

Spent all week - just waiting and waiting (eagerly!). Called up on Friday morning to see if it was ready..got advised to pick it up on Saturday (yesterday).

It's EVERYTHING I'd ever wanted in an exhaust system for something like the Aristo. Here are a couple of pics and video to follow:

I didn't have enough space to go further back than that to get more photo's but will do in a bit.

Performance: No boost cut hit yet at full throttle at 90mph ;). Car spins wheels upto 45mph plus from a standstill in the wet and dry with traction control cutting in. Car is completely decatted (no CATS!)...the boost comes on FAST and HARD! Car goes through the rev range quickly. Overall I'm happy. Sound/video clips coming up in a bit

[RH9]

I bet it sounds nasty when its on boost!

Did you get any pics of the front pipe section prior to installation? Did you keep the de-cat pipe less than 3 inches diameter to prevent the dreaded boost spikes they can (reportedly) cause? You mention a 4 inch down pipe but I would of thought there wasnt enough space!

Cheers :)

[yoshi]

You're probably going to get boost creep with that setup. It'll show up around 110-120mph on full throttle....it's really important that you get a Blitz boost controller fitted so you can see you peak boost and have it bleed off any excess boost.

[skeet94]

You're probably going to get boost creep with that setup. It'll show up around 110-120mph on full throttle....it's really important that you get a Blitz boost controller fitted so you can see you peak boost and have it bleed off any excess boost.

I'm seeing boost cut at over 110mph at full throttle. I don't intend on driving at those speeds anyway, so for now I am happy with it.

Also a boost controller wouldn't help bleed excess boost...a boost controller only helps to increase boost not lower it. The problem on our cars is the stock turbo's internal waste gate gets overwhelmed with a free flowing exhaust and there's no way to address that, except by using hybrid turbo's (with a modified wastegate) or restrictor ring or leaving the stock CAT on the car. I'm going to do something along those lines pretty soon anyway but for the moment I'm happy with it as I don't intend on seeing speeds near 110mph anywhere on a road.