How to improve air flow to the turbo

[UKJames]

1994 Volvo 855 T5 UK Spec 101,500 original miles.

Excellent site, I can't praise it highly enough guys!!

I appreciate that what I am about to ask is fairly fundamental to all of you, but I am not sure that I fully understand the air flow plumbing on my T5.

I have seen various posts on improving the air flow to the turbo, mine is plumbed with the main air intake to the turbo running north to south from the radiator over the valve cover, with air also coming from the air box to the turbo, not sure I understand this bit, can someone please explain?

Improving flow at the mouth of the air intake is difficult because of the position of the radiator, equally dropping the intake down to the base of the front spoiler for additional ram as suggested by Pete in Australia would be a bit of a no-no in the UK because of the rain we sometimes encounter.

So my question is this, has anyone else come up with any better ways of increasing air flow to the turbo. I have looked over and again at the IPD short Ram intake and don't understand the advantages of this modification, nor do I understand the reverse plumbing aspect on the IPDUSA Stage III V70.

I would like to understand all of this, would someone be generous enough to explain for me please?

Many thanks,

James.

[MadeInJapan]

For you to run over the top of the engine to the radiator (actually, intercooler), you already have reverse intercooler piping so it's the most efficient it's going to be to the intake manifold (this was changed later in '95 due to condensation freezing in extra cold climates). If you don't want to drop a pipe down in front of the air filter box (too much rain) then let me just suggest you use a K&N drop in panel filter- it will increase HP by about 2- barely noticeable. Other than that, get rid of any obstructions to the intake piping by taking out the little pastic guide right in front of where the pipe extend out to the front of the car- really, this is about the best set-up there is. Next, get your car to stage-0 and then have your ECU upgraded by IPD (or other folks who do this). Your car will fly fast enough.

[UKJames]

Hello MiJ,

Can you explain stage zero, or direct me to where I can find it on the site?

Thanks,

James.

[MadeInJapan]

I could but basically it just means to get your car up to the condition it was when it was new- make sure all vacuum hoses are sealed and not hardened or brittle- most of us have replaced with silicone hoses for instance from www.stylinmotors.com then make sure all plugs, wires, rotor and cap are good or new. Make sure the 02 sensors are reading correctly. Replace old turbo hoses- once again, many of us have replaced with silicone hoses and T-bolt clamps for extra boost. Make sure brakes are good too... once everything is like it should be, then begin to mod your car. If you mod before things are up to par, the upgrades themselves will cause weaker systems to fail. I didn't mention it but downpipes and different, better flowing exhausts will also add HP's as do ECU upgrades (IE: www.ipdusa.com). Good luck!

[UKJames]

What more can I say MiJ, many thanks for the tips and direction, it is really useful help and I will begin work right away to bring the car back to as new condition.

James.

[peffley]

noticed your tip about silicone hoses. What about silicone or poly type bushings - specifically for the control arms. Motor mounts and other places too? Any good sources for this or is OEM rubber the best route? Thanks.

[MadeInJapan]

poly bushings for the control arms is a pretty new thing on the 850- only a few vendors and I'm not sure who they are. www.ipdusa.com sells the poly engine mounts (well, at least a few)..check them out. Just remember that if you're holding the engine in place with poly, you'll get some increase (sometimes very noticeably so) in vibrations. I took my top engine torque arm poly mount out a few weeks ago and went back to OEM rubber due to the excessive vibrations in my S70. I have a poly engine to transmission (front belt-buckle) mount on the larger of the two bushings there. All other engine mounts are OEM, including the one under the timing belt...but I don't know anyone who makes that one in poly.

[peffley]

thanks again MIJ for the quick replys. I just figured poly would be mainstream with all the rescent growth/hub-bub (NeedForSpeed, FastAndtheFurious, Gangs, Street Racing, JapMods, etc.). I guess Volvos are for the slightly more "seasoned" croud Anyway... One more question if I may: I have to replace, at least my Right, control arm assembly and was wondering if the aftermarket assemblies are a good/safe choice for this area VS. the Orig.Volvo assemblies. The suspension components would seem to be a relatively important area with regards to quality and I'm not too familiar with using aftermarket in this important of an area? The IPD photos of the aftermarket parts look really good, I'm just concerned with the quality of the metal/forging/casting etc.. They say their up to specs but was just wondering your take on this. Thanks anyone/everyone in advance. -peffley

[MadeInJapan]

There's been a lot of debate on the topic of replacement part-especialy for the suspension and the general concensus is that you typically get what you pay for. On the control arms, stay with OEM Volvo parts...avoid ScanTech on any of the parts. Many aftermarket suppliers are just calling ScanTech parts "after market" so be careful. If you're looking for good discounts, call Daryl Waltrip Volvo and ask to talk to Don or Jamie in the parts dept (tell them you're on the forums for a discount). You'll have to google this to find it or I know someone has posted their information here- just can't locate it right now. Since Daryl Waltrip Volvo is a Volvo dealer, they only sell OEM parts, but at a discount similar to after market parts from other on-line vendors.
Good luck and let us know how things go.
-MIJ

[peffley]

Thanks again MIJ.
That's what I needed to hear and I'll be calling Waltrip for parts.
-Peff