400bhp...anything I need to know?
 

Hi,


My '99 classic is getting a 400bhp upgrade, in the very, very, near future.





Current:

• 2.1 Forged Stroker Engine
• Induction Kit
• AltaTek ECU
• Oil Sump Baffles
• Upgraded oil pump
• 330mm Big Brakes
• Coilovers
• Struts and Chassis Frame supports
• Walbro 255 Fuel Pump
• STI 6 Speed Gearbox, not DCCD
• Custom track clutch

Upgrades:

• STI v5 Heads
• MD321H Turbo
• H&S Exhaust
• FMIC

Is there anything I should be aware of...any gotchas that I should take into account?




Woka

What size injectors,what fuel pump and what intercooler?

very good point.
I believe there was talk about reconditioned pink injectors, front mounted intercooler...and I am trying to rack my brains to see if the fuel pump was upgraded when the engine was rebuilt. I think it was.

Might need some higher flowing injectors. Unless the flow is being changed as part of the reconditioning. I think pink ones would be at the very top end of their duty cycle at 400bhp.

Rebuilt at Richard Henry's by any chance?

Let Andy put the fueling package together mate :)

Yes it was. After my Dad totaled the engine at Croft :D
I believe you bumped into my car there once. Bumped as in "saw" not bumped as in "drove into" ;)
RH will be doing the upgrades on my car....I'm just an inquisitive little sausage and thought I'd ask some questions here to get more background knowledge on the upgrades.

As Joe says leave it to Andy you're in very capable hands :thumb: :lol1: indeed I do remember the car :)

Good morning.
Andy will be doing all the work. While I can, and have, stripped and rebuilt engines I feel the Impreza engine is well and truly out of my league...plus not have a workshop doesn't help :D


I was just picking peoples brains to hoover up all your knowledge so I don't have to bother Andy and his team with seemingly daft questions.

For 400bhp on a classic, a walbro 255 fuel pump, depending on what is available for side feed rails you will want 650cc injectors as 550s will be on the limit for 400bhp, I would consider running the fuel rails in parallel (can be done cheaply using a T-piece and some fuel hose) and an adjustable fpr

What about your gearbox and clutch? Uprated already or no plans at the moment? ( wait till it breaks??)

Just checked invoices. one of these fuel pumps got fitted during 2.1 rebuild.
I believe the absolute top end for my 2.1 stroker engine + MD321H is 410bhp....I think the T variant of the turbo can put out a bit more power, but is more suited to 2.5 ltr engines. So based on this are the 650cc injectors still required?
Please correct me if I'm wrong on this.

"Wait till it breaks" :D I don't work like that. I learnt a very long time ago that this way of thinking usually ends up costing more in the long run and things always break at the worst possible moment.
I like to be one step ahead of things breaking.
Currently, 6 speed STI gearbox (2003 if I had to guess), not DCCD, and a custom track clutch.
If I remember correctly the old 5 speed stock gear box was rated to an absolute tops of 350bhp.


Added to original post.

Thermostatically controlled oil cooler.

That's a new one to me. Expensive?
Is this really required...or a nicety?

Based on the size of the core/full kit but between £150-250, depends on the use really but more a nicety at 400bhp than a necessity :thumb:

depends though matey, my old classic ran hot, 100c on the motorway on a warm day, oil cooler sorted it and it ran at 340bhp for another 20k miles with no issue so i wouldn't even say it was a case of the engine being on the way out.

Higher bhp does tend to mean more heat, but the point at which it is required varies. Without testing your own setup you wont know, but given how critical oil temps are and taking into account the price isn't bank breaking, I would say it would be silly not to.

I agree to some extent but as said depends on the driving if its short local bursts with the odd run out you would probably get away not fitting one. Regular motorway or track driving then even at standard power its worth having one.

I only fitted one to mine as 2.5 block runs a little hotter so was worthwhile to get oil and water temps down and should I want to track it I have my bases covered :thumb:

You make a very good point.
While I have enough to cover the build, all these "extra" £150's very quickly mount up as I have discovered ever since owning my car :D
Tbh if I can get away without the FMIC this would leave me with a little extra.


My new twin engine 400cc pro-kart has dented my bank account slightly this year...but I don't by any means want to skimp, and take risky short cuts, on the Impreza upgrades. I also get the feeling Andy will tell me very politely that I'm a muppet if I ask for anything silly and say I don't want a required component :)


Edit: Not a commuting car. Weekend car, tracks days thrown in. Some motorway driving when going to visit family/friends.

Weekend and track use will be driven pretty hard so i'd fit one for def.

be interesting to know what temps it ran with and without, not that im suggesting doing it haha