OST-040: BOOOOSTed

[oldeskewltoy]

My new client is building himself a twincharged 4AGE. I believe it is going into an AW11. This client came my way, not by my many posts on here, or one of the many other forums, but through one of the machine shops I use. I'm also providing technical assistance to that shop with his block build (9.5:1 forged pistons). He is a "local" Portlandian.





As is usual the intakes are opened up, the short radius gets worked, and port to bowl alignment issues are corrected




The exhaust side gets opened up too. Since this head will be twincharged, the exhaust side is opened up a bit larger then is typical, a new SV3 exhaust gasket will be utilized.






more to come.......

[Bean]

Sounds intriguing, would like to see the finished build apart from your work. As squeezing all that parts into that engine bay is a challenge by itself.

[oldeskewltoy]

(06-29-2016 08:32 PM)Bean Wrote:  Sounds intriguing, would like to see the finished build apart from your work. As squeezing all that parts into that engine bay is a challenge by itself.

Part of the reason I don't fabricate....



Progress...

in my first post - #4 is shaped and ready for finishing, and #3 is still rough..... while below is a 2 panel showing #3 is now shaped




and as fitted to the new gasket.... and now comparing shaped #3 to as yet untouched #2





more to come......

[oldeskewltoy]

The intakes are all nearly finished....





and a bit closer on cylinders 2 and 3





more to come.....

[Ivan141]

What's the idea behind those flat cutoffs on the dividers of the exhaust port roofs?

[oldeskewltoy]

(07-07-2016 09:54 PM)Ivan141 Wrote:  What's the idea behind those flat cutoffs on the dividers of the exhaust port roofs?

Improved flow... as the bowls merge, the splitter becomes an obstruction... kinda like water skiing over a wake....




As "large" as those ports may look, they have actually "grown" only about 2mm in diameter.... they are still smaller then a stock Blacktop, but these ports flow more than a Blacktop's exhaust ports



With the exhausts now complete, its time.... the head goes into the machine shop tomorrow to receive its 3 angle and back cut.



more to come....

[oldeskewltoy]

Hmmmm, I missed un update.... (2 weeks ago - end of July)

The machine shop took nearly 3 weeks to perform the 3 angle, and back cut the intake valves....


but their 3 angle looks quite nice



The arrows are pointing to the seat/bowls that are not quite to size. Now that the valve job is done, the finishing touches are performed and now all the intake bowl/seats are @ 26.5mm, and all the exhaust bowl/seats are @ 22.0mm.....




Next... setting up the head for checking chamber volumes



and I've got one @ 37cc, and 3 @ 36.8cc...



I have a wee bit of work to do on chamber 1,3, and 4......


I'm holding off on the head cut, and final chamber volume until I know the actual deck height. The client purchased 9.5:1 pistons, and a .8mm gasket, AND wants me to keep static @ 9.5....



More to come.....



NOW a current update 8/8

oldeskewltoy Wrote:I have a wee bit of work to do on chamber 1,3, and 4......

head is now machined.....



and the final chamber volume........ on near identical chambers





Assembly to come... then setting the clients cam-valve clearances....


More to come.....

[Alex170984]

Toni Gladding on IMOC has a twincharged 4age HKS engine in her AW11 - it's been on sale for a while now.

What difference does de-shrouding it make?

[oldeskewltoy]

(08-09-2016 01:40 PM)Alex170984 Wrote:  Toni Gladding on IMOC has a twincharged 4age HKS engine in her AW11 - it's been on sale for a while now.

What difference does de-shrouding it make?

It allows the chamber to resist detonation better. The sharp machining marks tend to get hot and can cause pre-ignition, where as a smooth blended chamber wall tends to not get as hot, so less chance of pre-ignition

Simplified... you can run a bit more compression without causing "ping"

[oldeskewltoy]

oldeskewltoy Wrote:



Assembly to come... then setting the clients cam-valve clearances....

Now assembled.....



all that is left to do... is set cam - valve clearances......



more to come.......