What Cylinder Head To Use For Best Performance With 2.3L Block?

[austenw]

I believe he is doing 9K 9200 RPM on that engine. Could be that the belt starts to wobble. Polestar is using the same setup on their 8750 RPM NA engine.

Great info so far

Where can I get hold of one of those bearings and mounts for inbetween the cam belt pullys?

Here are some pics of my head set up

[fischmama]

Here are some pics of my head set up

OMG!!!!!! :o :o

[ozzimark]

Nice ITB setup. How does it behave at lower RPM? :)

[BlackT5]

Nice ITB setup. How does it behave at lower RPM?

I'm pretty sure his car isn't even close to running yet.

[fastwagonhawaii]

know tat is sexy as hell. cant wait to see it running. and prove 80% of volvospeed wrong. you know what they say: its not worth building an na engine just buy a turbo.

[austenw]

Nice ITB setup. How does it behave at lower RPM?

It will probably be as lumpy as hell due to the massive cams low down, but I got to use them to get the power

After all I'm not building a daily driver

I'm running 2 banks of injectors (10 in total) which are blended from bottom to top bank as revs increase so it will be smooth on fueling

[BlackT5]

It will probably be as lumpy as hell due to the massive cams low down, but I got to use them to get the power

After all I'm not building a daily driver

I'm running 2 banks of injectors (10 in total) which are blended from bottom to top bank as revs increase so it will be smooth on fueling

What EMS do you plan on using?

[austenw]

What EMS do you plan on using?

Ive used Pectel T2, MBE 961, MBE 970 in the past which were all good systems

The MBE 970 i used on my 4 cyl turbo motor ran 8 injectors that were phased in 2 banks and that drove great with 400 plus bhp

MBE developed that ECU for the British Touring car championship and it was used extensively by Honda for there 8 injector nasp set up

Unffortunately MBE does not support 5 cyl so I'm going to run a KMS MD35 (made in Holland)

I've been speaking with KMS for a few years at the Autosport show here in the UK and they have a few 800bhp plus 5 cylinder motors running there management system

One of my friends is running one on his Audi Quattro 5cyl with 500bhp and it looks like an easy system to map

[Fishey]

God, I hate threads like this...

1. Its a turbo car

2. Port Flow is only 1/2 the story but this thread has been dominated by OMG I can fit my fist inside the intake port and put 90mm valves in look how much CFM I can flow.

[greekone]

know tat is sexy as hell. cant wait to see it running. and prove 80% of volvospeed wrong. you know what they say: its not worth building an na engine just buy a turbo.

Ask him what he has invested in that engine. :lol:

[fastwagonhawaii]

Ask him what he has invested in that engine.

i know he has spent a grip on that setup. but remember, to get a truly good turbo motor its not a cheap adventure either. most people think and not just on this forum think that building a really fast turbo car is cheap. that is no where near true as you should know. If you spend 10 grand on a turbo motor. and 10 grand on an NA motor the power numbers will be different of course but the way the power is used is what matters. I have seen built NA's torch built turbo cars on the track. and i am sure you have too. this is an expensive game either way, NA or turbo.

[Fishey]

Lame, I was trying to start an argument..

Anyways, Here is my point.

Port velocity on N/A or Turbo cars are very important (but different)for the purposes of the original poster "lookforjoe" it is indeed a Turbo application in question.

The main difference between porting the two designs is in the port velocity required on both the intake and exhaust ports. The actual FPS of flow can be calculated on most flow bench machines. The reason that this velocity is so important on a turbo is for 2 reasons. The first reason is throttle response off boost a slow intake charge will tend to stall at low RPM (Pre-Boost) and make for a very sluggish motor at low RPM (off boost). Obviously, This aspect of flow isn't as important to a Turbo car as a N/A car because you have forced induction taking place after a certain RPM. Regardless, to make a engine street friendly it is advisable that you take this into consideration. The second and more important factor is the exhaust port velocity and this is extremely important on a turbo car. When you drop exhaust side velocity two things will happen the first is that with the decrease in port speed you will find that the turbo will spool much later in the RPM band. The reason is because instead of the exhaust side turbine seeing a fast and hard exhaust pulse it will see a lazy slow flow of air with almost no exhaust pulse (You can help this with ramp rate of the cam). I try to think of it as breaking a stuck bolt loose on a car if you have a wrench and can't force it to move with your pressure alone what do you do? You find something to bang on it. The second reason the exhaust port velocity is so important is because the speed of the air will effect scavenging (You can help this with overlap of a camshaft). Regardless, I tend to shoot for around 350fps on the intake port and 600fps on the exhaust port as it has been proven to be a pretty decent benchmark for efficiency.

-Your Pal

Fishey

[ozzimark]

Lame, I was trying to start an argument..

Why? Discussions are so much better, although I do know how much you love trolling people

Port velocity on N/A or Turbo cars are very important (but different)for the purposes of the original poster "lookforjoe" it is indeed a Turbo application in question.

Indeed, and the tradeoff that is acceptable depends on the setup and application in question. A turbo track car will have an entirely different setup from a turbo street car. When was the last time you drove on the track and cared about torque below 3000rpm?

The first reason is throttle response off boost a slow intake charge will tend to stall at low RPM (Pre-Boost) and make for a very sluggish motor at low RPM (off boost). Obviously, This aspect of flow isn't as important to a Turbo car as a N/A car because you have forced induction taking place after a certain RPM.

I don't see why turbo or non-turbo matters in this case. The flow velocity will be the same, and will have the same effect on both engines, you're just changing the density range a lot more on a turbo engine when going from low load to high load. Also, my understanding has always been that the low flow velocity gives poor fuel mixing, and depending on how it's set up, a drop in VE. Bad for a street engine that wants decent off-idle response, but good for a racing engine that will rarely see low rpm operation.

The second and more important factor is the exhaust port velocity and this is extremely important on a turbo car. When you drop exhaust side velocity two things will happen the first is that with the decrease in port speed you will find that the turbo will spool much later in the RPM band. The reason is because instead of the exhaust side turbine seeing a fast and hard exhaust pulse it will see a lazy slow flow of air with almost no exhaust pulse (You can help this with ramp rate of the cam).

Well, you're leaving something VERY important out here: the manifold design. By the time the gas pulse from cylinder 1 gets to the turbine wheel, it will be thoroughly shaped by the design of the exhaust manifold, and the flow out of the port isn't nearly as important as it would have otherwise been. I agree that velocity should be kept up, but not because of the pulses. Letting the gas sit in the exhaust port and manifold for too long allows too much heat to escape to the surrounding metal, bringing down the volume of the gas significantly. Obviously, less volume flow through the turbine wheel means less velocity hitting the blades... slower spool.

I try to think of it as breaking a stuck bolt loose on a car if you have a wrench and can't force it to move with your pressure alone what do you do? You find something to bang on it.

Which will most likely drop the efficiency of the turbine wheel. The efficiency plot of a turbine wheel is pretty similar to a compressor wheel. Instead of holding one spot just under the peak efficiency, for example, the flow will be pulsing. That will make the point oscillate between a lower efficiency, through the peak, and then back down to a lower efficiency. Of course, it depends on where you are in the map, but in most cases, that will reduce the overall efficiency of the turbine wheel. I know a lot of people argue that keeping strong pulses to the turbine wheel is best, but from designs of high performance manifolds, it seems the trend is the shortest runner length possible, and if feasible, equal length runners. The equal length runners will even out the pulses by spreading them out equally..

Regardless, I tend to shoot for around 350fps on the intake port and 600fps on the exhaust port as it has been proven to be a pretty decent benchmark for efficiency.

I don't doubt you on this, but can you show the tests that "prove" it? I love reading things like that :tup:

[Che'_Moderator]

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Is this your head?

The error they have made when flow testing this head is to use a 3.4 inch bore which is 86.36mm

I dont know of any Volvo 5 cyl running that size bore

Either 81mm or 83mm else it will show inflated figures as the valves are deshrouded which is not a real world tests in my opinion

That block is sleeved and bored over. Its also running a raised CR at just shy of 10:1 before a little last minute chamber work on the head. Your engine should be very strong. The reason others flow numbers seem low though is because they are flowing forced induction heads. So in a perfect world 200cfm at 3 bars = 600 cfm.

I do not remember the exact numbers but I only lost velocity below something like 2mm of lift with this set up. When I played around with larger valves I was loosing velocity all the way up to something like 6mm of lift. That was on an 8.5:1 2.4L engine but I doubt it would have been much different on a built engine

[lookforjoe]

My TT COP ECU should be on it's way to me at some point in Jan.. so, I'm now thinking more seriously about picking up a newer head.

Also wondering about intakes - since the 98 already has longer runners, what potential benefit is there to a design like Ajhehr when the runners will be shorter than what's already there. I can just port the '98 manifold to the later head, as others have done.