Thread: Port Matching manifolds to cylinder heads

PORTED AND POLISHED 8) 8) 8) 8) 8) Hopefully you have unlocked a few neddies.It can only be for the better.
Andrew

i'll test it before i tweek the pump to see if it changed anything

Steve, we used to use roll pins as locating dowels so that there can be no mis-alignment when grinding and refitting.
Funny you should post this as I've been toying with the idea of cutting the inlet manifold in 1/2, porting it and getting it TIGed back together.......
and FWIW, the inlet manifold becomes superheated by the exhaust manifold/turbo. I've had temp readings in excess of 77* on the top side of my manifold (under the acoustic mat that covers it) I'm going to insulate it very soon.

I actually cleaned up downstream of the turbo last weekend when I fabbed up a 3" mandrel bent exhaust. The original flange/60mm pipe off the turbo dump pipe (300Tdi) is welded internally, and a nice big mig bead closed the throat down to 2"x2.125".
I used 2.5" off the flange, then about 40mm below flared it up to 3" at @ a 15* taper and relieved the casting a little on the upside of the flange so it's now a nice, neat 2.375"/60mm transition.
The ability to rev, and the much quicker spool up at the bottom end was very nice. It also dropped maximum EGT's by between 23* and 40* on my test hill. I've since tweaked the pump, and it's now bloody lethal... I'm going to advance the pump timing a little this morning and continue to fine tune the fuel delivery. What you said in another post re the pump timing on a stock engine was spot on, but when you increase the fueling, you are increasing the time that fuel is injected into the cylinder, and so it makes sense to start it a little earlier to bet a more complete combustion. If the theory is right, I should see it straight away with lower EGT's.

Let us know how you go on the tweeking........... :roll: pump that is...

Its funny how we go around one full circle to achieve the very small amounts to gain HP.
i'm only doing this as the manifolds were off at the time and i have the tools and knowledge, but as for major tweeking on the pump, nope, just basic tweeking. i'm happy with the way my fender goes, if i can get it to go better i will, but i'm not wanting it, if you know what i mean.

When i was rallying, i did some awsome modifications.
Modified the head, ports, manifolds, exhaust, ignition curve, injection timing (Bosch D-jetronic) Cam ect.... it was nice to have a 3 litre straight six that was std 170hp go up to about 250hp. so i spent about $3000 in work to get that extra 70-80hp. Did i win any events?? Nope.... Volvo 164 are great endurance, but like all front heavy cars, Understeer. No amount of tweeking the double wishbone front end stoped it, i reduced it heaps and learnt how to drive with it............ Man that car was fast.... with a 4.1 back end on a bitumen road it would lay rubber until you grabbed 3rd.
Now it lives in Werribee and some young blokes are doing it up for more action.
I did think about putting a Volvo B30 engine in a series LR..... 170hp in a Series 3 or Series 2a...... Nice...

<div class='quotetop'>QUOTE</div><div class='quotemain'>Its funny how we go around one full circle to achieve the very small amounts to gain HP. [/b][/quote]

Yep. As you said, bits were off and the tools were just laying there unused....

funny thing is I've had the Deafener over four years now, knew how to adjust the pump, knew a decent exhaust would help yet could never be bothered as it's only a Landy, been there, done that on race cars and been paid to do it, it's all in the past, etc, etc.

Then I had a brain snap two weeks ago and ordered 7, 90* mandrel bends and 6m of 3" exhaust tube and went nuts. My excuse was "the Patrol needs a new 3" system as it's overheating when towing. I'll practice on the Defender first..."

Mid life crisis, me thinks..... ops:

And the results are in.

Before the modification it used to take me a long time to climb this one hill and i had to drop it down to 4th.

Now....
I can climb the hill in exactly the same time and i still need to drop it to 4th.

So the net result in real time was ZILTCH.....

At least i did it and it was only my tim and the cost of a gasket, well not really... i fitted the EGT at the same time.

Originally posted by sclarke


Modified the head, ports, manifolds, exhaust, ignition curve, injection timing (Bosch D-jetronic) Cam ect.... it was nice to have a 3 litre straight six that was std 170hp go up to about 250hp. so i spent about $3000 in work to get that extra 70-80hp.

ahh, finally a language I can understand.
Luv the smell of avgas in the mornings,,

9000rpm redines and 48mm webbers,,
the only thing better than the sound of a V8 is the induction noise from twin webbers at 7500rpm. offset ground and flowed cranks, welded combustion chambers, 35in exhaust primarys to a 12inch long Lukey that managed to fall off every race :roll:

yep the shirts are true.
the older i get the faster I was

<div class='quotetop'>QUOTE</div><div class='quotemain'>the older i get the faster I was [/b][/quote]

yep, same here

all my left over avgas went into my F100 (dual fuel). With 4V valves in 2V quench chamber heads, it was the only liquid fuel it would run on, and it was only my tow rig....

Way before that I had a V8 Commobore wagon that carried my kart across NSW and Vic. All the left over pre-mix went into that. Ahh, the smell of Castrol R30 at a set of traffic lights.......