stayer

Hi friends!
In this topic I want to talk about the work with the cylinder head. Earlier, in its various topics, I mentioned that doing a big project 4G69 (N/A). The planned capacity of at least 100 HP per liter volume. I think it will be more. When I assemble the entire engine, I will write a separate topic. And give links to threads, where and how were these or other work.
To obtain such power, it is necessary to modify almost all the parts.
In this topic I will talk specifically about the cylinder head.
I had a spare cylinder head. With this head and started work.


I want to remind you, I don't understand English. Write with a translator. If you do not understand some words, ask, I'll try to find another explanation.

stayer

Initially, we need to understand what we're working with. For this we need to examine the cylinder head on the flow stand.

stayer

I want to say. What 4G69 cylinder head very high-tech. It shows good results with purge flow test. Its performance is much higher than the 4G63 or 4G64.
I also did the spilling oil. It is necessary to understand the degree of compression. The volume of the chamber is 51 cm3

stayer

Previously, the cylinder head is thoroughly washed.

Now, the task is to increase the capacity of valves at the inlet and outlet. In this place the plugging. If you do only the increase in channels, will be of little avail. It is necessary to increase the size of the valves and seats.
Stock valves:
intake 34 mm
exhaust 30.5 mm
The same size valve has a Evo 9. I think can add +2 mm for this size.

stayer

However, there are a few problems.
For example at the intake valves. The distance between the saddles more than 6 mm.

It's all good, can make a +4 mm. However, on the other side of the valve is really bad.

In the picture where the screwdriver is. This place is not to increase more than 1 mm.
Even if you increase more than 1 mm, then this place is not the movement of the air flow.

stayer

The same problem with the exhaust valves.

So. The maximum that can be supplied is +2mm intake, +1.5 mm exhaust.

stayer

First, remove the seat.

stayer

New seat mounted with an interference fit.


As you can see, the size of the saddle a lot more than internal size.

stayer

After installation of the valve seats, it is necessary to cut the working chamfer. At a certain angle. For example, here is a video as to cut the chamfer. It's a different cylinder head (4G63). But the meaning is the same.
www.youtube.com/watch?v=WYqOQGiKnyY

enough for today

bakuro117

iTrader: (5)

Very nice! I cant wait to see more!

stayer

Will continue.
After the valve seats. Need to find new valves. I originally planned to install the valves from car Honda NSX. Inlet 36mm, exhaust 32mm. But these plans had to be abandoned. These valves are not the same length. They are much smaller.
I've been looking at different catalogs from different manufacturers. Ultimately bought the prefabricated. From Ferrea.

Ferrea Competition Plus Valves have built a reputation as the industry's most reliable extreme duty valve. To manufacture the valves we use special aerospace quality alloys, including the EV8-Z18, which provides high tensile strength. An exclusive two-step slow forging process ensures proper grain flow and virtually eliminates any damage to thematerial structure. The valves are then heat-treated and stress-relieved over a 48-hour period, which is the crucial base of our molecular integrity. These valves feature avionics-quality hard chrome along with a specially applied hard tip.

stayer

Will continue.
After the valve seats. Need to find new valves. I originally planned to install the valves from car Honda NSX. Inlet 36mm, exhaust 32mm. But these plans had to be abandoned. These valves are not the same length. They are much smaller.
I've been looking at different catalogs from different manufacturers. Ultimately bought the prefabricated. From Ferrea.

Ferrea Competition Plus Valves have built a reputation as the industry's most reliable extreme duty valve. To manufacture the valves we use special aerospace quality alloys, including the EV8-Z18, which provides high tensile strength. An exclusive two-step slow forging process ensures proper grain flow and virtually eliminates any damage to thematerial structure. The valves are then heat-treated and stress-relieved over a 48-hour period, which is the crucial base of our molecular integrity. These valves feature avionics-quality hard chrome along with a specially applied hard tip.

stayer

Now I just need to cut off the desired length and make a castle for spring.

In the photo above the exhaust valve. Its length in the factory manual is written 113.49 mm. However, I made a different camshaft. I wrote about it in this thread
https://www.evolutionm.net/forums/04...-kit-4g69.html
I wrote that it is necessary to produce thicker rollers. In this case, this should not be. I just made a longer valve +0.50mm

stayer

Final length is measured after full preparation. For example, the measured length of the stock valve.

This length takes as a starting point 0.00
Next, measure the new valve

As you can see in the photo, the length is longer at 0.211 mm
Further, the end valve grind 0.00

stayer

I also want to say. The thickness of the stock valves 6mm. New valves intake also 6mm.

And the valves on the exhaust have a smaller thickness. 5.5 mm