Inlet/exhaust port matching - worth it?

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DPP
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Re: Inlet/exhaust port matching - worth it?

Post by DPP »

Grant that looks the dogs doohdas, are you planning to put it on a dyno as I would love to see a video of it run up and see what the figures are.

You must have a good weight saving there with all those aluminium parts.
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Grant
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Re: Inlet/exhaust port matching - worth it?

Post by Grant »

Hi DaveMan :P , thank you so muchImageyes it looks so cool doesn't itImage, yes, we were ready to Dyno it just before I came away,, then the dyno man went away and as he returned we went, so bad timing there, The minute I'm back I'm wizzing it up there with vid camera in hand, this is a 400 block, so same crank and rods as a 383 but with larger diameter pistons than a 440, only by a tad though.. I'm a very exited chap Dave :P
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Dino Fritz
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Re: Inlet/exhaust port matching - worth it?

Post by Dino Fritz »

Hi everyone,

Agree with all of the recommendations re. inlet / exhaust port matching - free horsepower to be had!!!

Just one addition - with all of the discussion of 30 / 40 thou oversized bores, zero deck heights, etc, PLEASE ensure that you have correct clearance between the piston and the head (from memory, it should be a minimum of around 90 / 95 thou).

When I re-assembled mine, I had zero deck height + 30 thou pistons, and when I checked the piston to head clearance (without gasket), it was virtually nil around 0.5mm from the edge of the piston - if it remained standard bore, all would probably have been okay. Easily fixed (just a buzz off from the edge of the combustion chambers on the head), but this is a disaster you want to avoid.

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Re: Inlet/exhaust port matching - worth it?

Post by DaveV8 »

All Andrew asked was is it worth gasket matching. The only answer he needed was no!
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RockyUSA
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Re: Inlet/exhaust port matching - worth it?

Post by RockyUSA »

But I thought we all agreed that he needed to do port matching!

(It’s not our labor!)

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Re: Inlet/exhaust port matching - worth it?

Post by Grant »

DaveV8 wrote:All Andrew asked was is it worth gasket matching. The only answer he needed was no!
Good Morning DaveImage, well I found it absolutely perfect timing to show off your exemplary workmanshipImage
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Kevin Birch
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Re: Inlet/exhaust port matching - worth it?

Post by Kevin Birch »

Hi Grant,

That looks a fantastic engine, but one query, I thought you weren't supposed to paint the inside of the V as this is effectively inside of the engine, and if the paint flakes will contaminate the oil and can block the oil pick up. If you want to, you can always do another engine and give that one to me so I could run it and see if the problem occurs :D

Fitted the new inlet on mine, but having issue with the choke now as it isn't getting warm very fast, so am ditching the auto choke and engineering a manual choke which shouldn't be too difficult.
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Grant
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Re: Inlet/exhaust port matching - worth it?

Post by Grant »

Kevin Birch wrote:Hi Grant,

That looks a fantastic engine, but one query, I thought you weren't supposed to paint the inside of the V as this is effectively inside of the engine, and if the paint flakes will contaminate the oil and can block the oil pick up. If you want to, you can always do another engine and give that one to me so I could run it and see if the problem occurs :D

Fitted the new inlet on mine, but having issue with the choke now as it isn't getting warm very fast, so am ditching the auto choke and engineering a manual choke which shouldn't be too difficult.
HiYa Kev, if it is prepared and primed properly it won't come off :wink: ..Not up for swapping yet My Ole Fruit Bat :P
Kev.. I much prefer a manual choke, and gearbox for that matter!!.. Manual is the new Yoga even when it comes to chokes, you tell it what you want to do, not the other way round!!.. Why should your car tell YOU what to do,..Like the ladies Kev.. if they do that.."Kick Em Out" :lol: :lol:
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Re: Inlet/exhaust port matching - worth it?

Post by AndrewP »

DaveV8 wrote:All Andrew asked was is it worth gasket matching. The only answer he needed was no!
Haha..sorry just dropped back into this post.

Seems to have opened a
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:)

Thanks everyone for the input and info. As I suspected, there are lots of answers..all right depending on what you want to get from the activity and what you want the engine to be at the end.
I will probably just do a clean up of all the flashings and the finger test down the inlets and exhaust throats.
Not entirely sure from the info in this thread that its worth port matching as the gains are minimal, especially if no other changes are being made (standard +040 flat top pistons, slightly hotter cam, but standard lifters and followers).
Im not even intending to deck the block as Id then have to look at machining the inlet manifold to match so whilst interesting looking at some of the info sheets, if I were to be going for more horses Id be looking at these more closely...but no doubt need deeper pockets also.
I HAVE to keep this build within a budget otherwise it will be off the road for too long and I want to use it over the Aus summer.

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Re: Inlet/exhaust port matching - worth it?

Post by sticky »

Grant that looks the nut's it cant be far off firing up stick a big f off turbo on it and watch the flames come out of the massive exchaust.

cheers jealous JIM
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Grant
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Re: Inlet/exhaust port matching - worth it?

Post by Grant »

sticky wrote: Fri Dec 11, 2020 2:53 pm Grant that looks the nut's it cant be far off firing up stick a big f off turbo on it and watch the flames come out of the massive exchaust.

cheers jealous JIM
:lol: Hello Jimbo..Strange you should post this today..We are firing it up on Monday and running the cam in..I'll stick a Video up Jimbo..Hopefully won't be needing a turbo as I hope it will have enough power to do half hour in 20 minutes!! :lol: ..Wishing you all the best Jimbo..Happy Christmas to you and your wife sport :wink:
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