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Posted by: Jake Raby Aug 17 2004, 08:46 PM

Thats right.. Even with the talk of conversions, sixes and Chebbies I am still trying to develop the best 4 cylinder in the world for the 914 guys that believe in what we are doing!!

http://www.shoptalkforums.com/viewtopic.php?t=76337

That explains it all... Excellent flow, excellent plug location, and excellent chamber shape....

And it all hides under the sheetmetal and just needs a new heater box/header flange to bolt right up!

This should be god for 20 HP on my engine and barely push it over 200HP as a full time street driver, with a dual purpose lifestyle of AutoX and track days...

Posted by: rick 918-S Aug 17 2004, 09:34 PM

Good to see you trying new and bigger things. Do you have any plans to test the Kit injection on it?

Posted by: Racer Chris Aug 17 2004, 09:55 PM

If I'm not mistaken there is already a performance header available that will fit this application.

Posted by: Jake Raby Aug 17 2004, 10:24 PM

Yep... And I'll be needing the Square port stubbies for it Chris..

No EMS on this one. I have to keep the engine bay clean and easy to tear down fast, no wire harnasses and clutter on this one..

BTW, it will feature the 914 version of my DTM...

Posted by: Verruckt Aug 17 2004, 10:39 PM

I'm fairly new here so don't know if I may have missed this before...

Any plans on having this design cast ??

Posted by: Racer Chris Aug 17 2004, 11:04 PM

It's probably cheaper to do weld build-up and re-machining, considering the quantity that will be used in the near future.

Posted by: Jake Raby Aug 17 2004, 11:25 PM

Nope, no casting of this. Mods like this take tons of hours to do..

I'm building my own heads with a Type I exhaust port for maximum performance and those are made from Billet since we are doing low production runs of them.

Its all experimental till we get the data!

Posted by: Jeff Bonanno Aug 17 2004, 11:35 PM

What will the valve sizes be?

jbb

Posted by: Brad Roberts Aug 17 2004, 11:46 PM

When will we have some water cooled heads ?? Ala 962/959 style: air cooled cylinders and water cooled heads ??


B

Posted by: Jake Raby Aug 18 2004, 12:11 AM

Water, what the hell is that??
It belongs no where around a Type IV.

This particular set of heads will have 44x38 valves. Thats perfect to get our 80% E/I ratio and plenty of filling for the chamber..

The #1 configuration issue I see time and time again is too large of an intake port and too much intake valve! The more charge you add the harder it is to attain your 80% and since you only have so much to work with on the exhaust port you reach the point of dimenishing returns very fast. That huge intake valve is just arder to control and only helps at very low lifts... Otherwise its diameter is actually in the way of flowing.

The largest intake valve we run is 44mm, even on a 102mm bore. My big heads have a 53mm intake and 43mm exhaust but they flow drastically different than stockers!

Tghis should be the best stock casting head for a Type IV engine period-

Posted by: Dominic Aug 18 2004, 07:37 AM

Jake,
Speaking of square ports....What is the difference performance wise between a 914 2.0 head and a square port 2.0 bus head with the plug relocated as you have mentioned in the past ?
Inquiring minds want to know.

Posted by: Jake Raby Aug 18 2004, 07:53 AM

I have never done the mods to the same engine back to back before with a oval port Vs. round. We have always made drastic changes to the squareport and do not know exactly what changed our powerband..

With our squareports we are able to gain atleast 25CFM out the exhaust port, so the changes are BIG, especially in the upper revs. Torque has went up 20% on some engines with these..

Posted by: Brett W Aug 18 2004, 08:20 AM

Brad I am seriously thinking about some watercooled heads to get the HP I want but I am still in the early stages. If you really want to do this right Porsche had it right watercool the heads. Aircooling is just not worth all the air.

Posted by: rhodyguy Aug 18 2004, 08:24 AM

jake, will the gains be negated for those of us that need/want to run heat exchangers? do you do test pulls with he's? do you test only on 2270cc or do you test for 2056cc too? as you say the correct combo is the key.

kevin

Posted by: Jake Raby Aug 18 2004, 10:13 AM

Not doing much with the 2056 anywmore. I have the cost of the 2270 down closer to a 2056 and its a better bang for the buck.

I do not test on the dyno with HEs, but have many combos of 2270 that run them everyday..

When our roller stuff is perfected I will do more with the 2056, as it will make equal the power of a conventional 2270 and should be a tad more affordable and allow more camshaft with no interferance with the crank/rod assembly..

Posted by: rhodyguy Aug 18 2004, 10:23 AM

i love that affordable word. expedite on the roller issues please. with the better head configuration is the need for an additional oil cooler pretty much eliminated? thanks for the info.

kevin

Posted by: Jake Raby Aug 18 2004, 10:30 AM

Alot of my engines don't need external coolers... The gearing in the tranny and tire sizes has more to do with needing an external cooler than my engine does..

RPM= Oil temps add the ambient temps and those are the deciding factors.

Posted by: Dominic Aug 18 2004, 10:38 AM

Jake,
If I'm building a 2056 with flat top JE pistons and Biral barrels (also be using an old CFR 4-2-1 header) Do you think I will be better off with a modified 914 2.0 head or the modified 2.0 Bus square port head ?

I almost forgot to mention that this engine will be fitted with a set of Dual Jenvey 45mm TB's with programmable engine management and crank fire ignition.

I am keeping the Type 4 faith just to let you know. I like the idea of more power and less weight.

Posted by: Jake Raby Aug 18 2004, 11:20 AM

Thats according to who is doing the heads and how much they flow.... Everything is dependant upon something else!

Posted by: Verruckt Aug 18 2004, 09:28 PM

Just curious..

If I were to go searching for a set of these square port heads, what years were they produced for the vanagons???

Posted by: Jake Raby Aug 18 2004, 10:10 PM

79-83..... BUT, just buy new ones and work with them. The old ones had tons of core shift in the molds around the exhaust ports and they are very thin and can blow a holr through the exhaust port... The new ones are thicker there, but don't trust their guides, springs or seats- replace them.

Posted by: Mueller Aug 18 2004, 11:07 PM

....damn you Jake.....it's not too late to sell my VR6 engine is it???? just kidding or am I ????

Posted by: Jake Raby Aug 19 2004, 12:17 AM

You already went to water.... You ain't kool anymore-man!

Water sucks!