Volvo head...on the car!

Colin · Post by **Colin** » Mon Oct 10, 2005 12:41 pm

The head is getting ported currently... the guy's had it for a couple months already... he's taking forever, but I hear he's good at what he does. I'm going to build a different header for it, and I'm toying with the idea of building a new intake mani, as well. I'd like ITB's and a plenum that clears the stock hood... but that may have to wait until I get the engine running with the current manifold.

I'll be running it on Megasquirt with EDIS.

Colin

GeneticRehab · Post by **GeneticRehab** » Mon Oct 10, 2005 8:55 pm

I remember you having the curved upwards intake. Have you thought of basing you intake off the cossy? The runners are fairly short but staight. I'm sure you have seen pictures of the inside of the intakes. This would keep up under the hood. But the brake booster maybe in the way? What ya think.

Colin · Post by **Colin** » Tue Oct 11, 2005 1:33 am

I dunno.. I think I'm just going to graft a DSM bump onto a junk hood for the time being. That should get me going until I have the skills/monies to build a better ITB intake... in the words of Atmosphere, "Not good, but I know it'll do."

Colin

wilky · Post by **wilky** » Tue Oct 11, 2005 8:51 am

Colin wrote: I'd like ITB's and a plenum that clears the stock hood... but that may have to wait until I get the engine running with the current manifold.

Colin,

Whats the advantage of ITB's (apart from looking different & the important cool factor)? The only think I can think of is that you would be able to tune each port for equal flow - what else am I miising and what TB's would you use?

I've been looking into ported stock, Essy and Volvo and think Volvo is the right choice for me. Also, could you please post a pic of your head that shows the weld mods you did.

More power to ya Colin - looking forward to seeing you blow some non green doors off at Carlisle.

Wilky

Colin · Post by **Colin** » Tue Oct 11, 2005 12:06 pm

The ITB's improve throttle response. I'm planning to use some velocity stacks inside the plenum, as well.

A block must be welded to the rear of the head to cover one oil drain hole and two water jacket ports.

I chose to run my oil supply up the side of the head instead of running it externally via hoses. I had a welding shop build up material on the side of the head, then drill a hole straight through from the oil feed (next to head bolt) to the oil galley in the upper head.

The hole marked "oil supply" was not originally in the Volvo head. I had that drilled by the machine shop after they welded the side of the head.

Weld the center oil drain hole shut. Reduce the size of the outer two.

MerkXRTurbo · Post by **MerkXRTurbo** » Tue Oct 11, 2005 12:16 pm

Velocity stacks do nothing on a turbo.

Colin · Post by **Colin** » Tue Oct 11, 2005 12:21 pm

The following images are taken from turboford member Stackz' page.

Head's too short.

His extension block.

Stackz had the entire mating surface of the head widened by the welding shop. According to Stackz, "I had the machine shop weld along the sides to bring it out far enough for me to feel comfy with. They simply evened it up with the aluminum block for me and then ground it down on the sides to make it look cleaner."

WIDE.

Definitely no gasket blowing problems here...

Oil feed line drilled into the block...

A rubber hose... that makes me cringe.

Different approach to the timing belt routing... I think he's using a 2.0 Mitsu belt. Mine is a 3.0 Stealth SOHC belt. I'm pretty sure Stackz is going to have a little coolant seepage around that tensioner bolt hole...

Colin · Post by **Colin** » Tue Oct 11, 2005 1:39 pm

MerkXRTurbo wrote:Velocity stacks do nothing on a turbo.

How do you figure? Any airflow modifications that work on an NA engine will also work on an engine with forced induction. It's a little harder to include velocity stacks in a turbo manifold, but the performance dividends are worth it.

Remember: all a turbo does is increase the density of the air. It's not BLOWING air into the engine.

Post by **John Brennan** » Tue Oct 11, 2005 2:24 pm

Well, in general, I'd agree that SOME mods which work for n/a engines will help with forced-induction engines, which is the basis for the four-valve head in the first place-- if the thing your blowing air into has less resistance, you'll generate more horsepower-- however, if a turbo doesn't blow air into an engine, what does it do?

Compressing air heats it up, which reduces density; that's why intercooling helps to restore it. Intstead of the give-and-take of increased pressure/reduced density, you have increased pressure/increased density.

Colin · Post by **Colin** » Tue Oct 11, 2005 3:35 pm

TouchÃƒÂ©.

MerkXRTurbo · Post by **MerkXRTurbo** » Wed Oct 12, 2005 9:42 am

You won't increase velocity of the air with velocity stacks, because the turbocharger already does that, and all you'll be adding to it with the stacks is a restriction in the intake. I know that there is desagreement on weather or not a turbo increases velocity or just compresses air, but I can guarantee you that it does both. When you let air out of an air compressor (think of this as the equivlant of an intake valve opening) then it comes out at high velocity, right?

Post by **DPDISXR4Ti** » Wed Oct 12, 2005 11:42 am

Man Colin, that's a helluva blob of aluminum he added for the oil feed! But I like that approach - it also adds a little more stability for the chunk added to the back of the head. I suppose the barbed fittings approach will work ...well, for awhile any way.

wilky · Post by **wilky** » Wed Oct 12, 2005 8:46 pm

Many, many thanks Colin - the pictures are worth a million words.

Wilky

wilky · Post by **wilky** » Wed Oct 12, 2005 8:47 pm

My cossie has stacks inside the intake plenum.

Wilky

KingpinCEO · Post by **KingpinCEO** » Wed Oct 12, 2005 9:56 pm

i disagree with luke G.

i think the stacks help.

like the bell mouth turbo inlets.

in the plenum.... i dunno maybe. any little bit helps.

this calls for a race between luke G, and colin.