Spool up

**mhill53** · Tuesday 20th December 2011, 08:42

I wonder if anyone can help? My r is running a forge mbc, forged internals and I've adjusted the actuator to get rid of any free play, it's running a standard ecu and I've got the mbc set to 15psi, I know cold weather will help spool up but it seems to hit the fuel cut now in 5th in no time at all, if I give it a boot full on the motorway overtaking the boost gauge shoots up straight away where as previously the car has took longer to spool in theory making the gears feel longer,it's certainly still a quick car but different in it's power delivery? it spools so quick now the car seems slower ?it's not clutch slip or anything daft like that,it can't have a leak as it holds boost an I wouldn't expect it to boost so well with a leak? Should I just back the mbc off a couple of clicks until I get the car remapped?

**M-R-P** · Tuesday 20th December 2011, 08:47

In a word, probably. it sounds like it's protecting itself. It won't know it has forged rods and the standard map could be panicking. Best not to boot it till over 3000 rpm. 3rd gear overtake from 60 should be fun tho...

**mhill53** · Tuesday 20th December 2011, 10:06

I agree mate, I've kept the standard map while I ran the engine in, it's now done 5000 miles so I'm enjoying it more now,I will get it mapped after Christmas so I can run a little more boost , I was only head scratching as it spools up so fast but in saying that it hassnt been more that 2 degrees of an evening lately, I will turn the mbc down a couple of clicks while it's so cold and while I'm waiting to get her mapped.

**M-R-P** · Tuesday 20th December 2011, 10:20

In this weather, do you really need all that ooomph!

I'm having trouble getting the power down in third with the early morning dampness and i'm only just over bog standard. nothing like your mods

**mhill53** · Tuesday 20th December 2011, 11:41

A good point well made mate, it's only performance gain would be the mbc as the internals are only there for strength and it's still running a 16t, it's plenty fast enough especially as my mrs drives it harder than me!

**M-R-P** · Tuesday 20th December 2011, 11:50

Mine's a ME7 so MBC will only upset it lol. You should be making ~16 psi with the MBC giving BIG improvements over standard.
I have managed to tighten the W/G actuator (till it threw a light and a code then I backed it off till it behaved) did a partial stage 0 tune, fitted a powerflow cone filter and trained the ecu to be more aggressive.
A few bits of tinkering with the suspension - mainly replacements but I managed to throw some polybushes in for good measure

Standard, she's 247bhp but, hopefully, she's a bit more now.
Like I say, with the way the roads are at the mo, it don't pay to have a heavy foot!

EDIT You're lucky, Mrs. MRP drives slow enough to drive Miss Daisy!

**mitchyboy01** · Tuesday 20th December 2011, 12:22

Get a custom map and run loads of boost. You've gone to all the expense of forging the engine so you may as well enjoy it!

**T5frankie** · Tuesday 20th December 2011, 12:39

Sounds like an overtightened actuator to me.

**claymore** · Tuesday 20th December 2011, 12:50

/\ /\ /\ what he said /\ /\ /\

**p fandango** · Tuesday 20th December 2011, 14:02

Originally Posted by mitchyboy01

Get a custom map and run loads of boost. You've gone to all the expense of forging the engine so you may as well enjoy it!

going to need a bigger turbo for that, you'll soon get out of the efficient range & just end up making heat instead of power

**mhill53** · Tuesday 20th December 2011, 16:44

You think the actuator is wound to tight?

**M-R-P** · Tuesday 20th December 2011, 17:02

It should just drop on to it's peg, possibly a bit of a tug to get it on

**mitchyboy01** · Tuesday 20th December 2011, 17:06

Originally Posted by p fandango

going to need a bigger turbo for that, you'll soon get out of the efficient range & just end up making heat instead of power

Too right mate. I see people who have forged their engine and make them capable of withstanding 400+ bhp then leave the rest. Surely if you have gone to all that expense you should change the injectors, get a nice big turbo and get a custom map for silly power. Otherwise what is the point?

**T5frankie** · Tuesday 20th December 2011, 17:28

Originally Posted by mhill53

You think the actuator is wound to tight?

if boost is coming in way to early then yes

**mhill53** · Tuesday 20th December 2011, 18:07

The Volvo is my everyday car so I don't want an unreliable "does nothing till it comes on boost car"
I forged the engine because i knocked the bottom end out of it shortly after buying it, it's more for strength than performance, I see what your saying as regards the expense but I enjoy making things fast but fast to last, my main toy is a Nissan s13 drift car with an ls chevy motor in, I need to tow this up and down the country with my Volvo so I don't want a balls out tow car just something tough fast and reliable.

**claymore** · Tuesday 20th December 2011, 18:15

I would suggest removing the mbc and getting a HLM map on it, that will sort out your aggressive boost and remove your boost cut problem.

**M-R-P** · Tuesday 20th December 2011, 18:46

I'm not sure if pulling a trailor and car with an engine that boosts hard and early is pushing your luck...?

**mhill53** · Tuesday 20th December 2011, 22:36

Have backed the actuator off 2 turns and the boost definatly comes in later now, will set mbc accordingly , what do you boys use to set the actuator preload up with? Gauge? Pump?

**M-R-P** · Tuesday 20th December 2011, 22:44

You can bodge a footpump and adaptor hose to give you a rough idea. Otherwise, as i said earlier, the actuator arm should just drop over the peg with maybe a little bit of persuasion.
There's probably better solutions on the forum but there's mine