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Okay....
I have been putting a tn of time into this combination and decided to reveal what I can here for now. What I'm about to share is much more general that I would like for it to be, but due to my lurking shadow that lacks originality I must keep things this way.

The amount of interest in this project that Len and I dreamed up has been phenomenol and has gained the attention of those that are not even partial to the Type IV conversion- That is what we ALWAYS like! Due to this interest we will be documenting the entire powertrain package as it is built as much as possible without disclosing particulars.

Project Objective:
To create a super efficient long stroke small bore Type IV engine and 4 speed transaxle combination capable of achieving 50 MPG under normal highway conditions. The goal is to create this powertrain package to operate at modern freeway speeds and attain the desired MPG goal. The engine will be designed to operate safely on 89 octane fuel. Overall HP goal is only 110 HP, but my projections so far has shown that much more may be a capability with the right camshaft choice.

The Car
1979 Beetle Convertible. This car belongs to my Girlfriend Beth and will be decked out in true Germanlook style with a fair share of carbon fiber accents, including the one and only silver carbon fiber DTM! 16x6" Boxster alloys with Kumho rubber on all 4 corners, Topline MAXX struts, disc brakes on all 4 corners and a sweet silver paint job. At the present the car is in stock trim but the entire suspension and brakes are getting a good going over this weekend. She will continue to drive the car with the stock engine until the highly efficient engine is dynoed.

Since the car belongs to "Her" I figured it would be a perfect test for the engine in question. For her car the necessity of a ton of torque to get the heavier vert rolling is a welcomed benefit while smooth performance will help keep her in the driver's seat of the bug and out of her damn Trail Blazer thats now the daily driver at the present. This will definately be a "Driver" car and not a show piece.

The Engine

I will break this down into segments so I can go over each area in more detail.

Engine internals(bottom end)
RAT 78.4mm crank with TI rod journals and a "perfect" rod ratio, based on a 1.7 EA code Virgin TIV case that I have been saving for years for a special project like this. I will be using a stock weight 210mm RAT MOD bus flywheel to get the power transmitted into the gearbox. The crank and rods are the only part of this engine combo that really are not receiving much attention other than being cryoed like all the other components. I do plan on running our proprietary friction reduction coatings on all the bearings and have adjusted the crank clearances for proper runing clearances. I have had the crankshaft ION Nitrided for a superior hard finish and friction reduction.

Cylinders and pistons
90mm 1700 TIV cylinders will be bored to 90.5mm to facilitate the incorporation of 90.5"B" Type I pistons. These cylinders will be NIKISIL PLATED! This is something that Charles from LN has done with excellent results in some 616 (356 Porsche) engines and we have decided to shell out the coins to do it to this combination as well. The Nikisil will allow us to run some very tight skirt clearances even with a cast iron cylinder which will reduce crankcase pressure and will better support the pistons at TDC and BDC. The Nikisil will drastically reduce engine friction and that equates to lower oil and head temperatures. While the NIKISIL plating of a stock cylinder is by far "Cheap" it is much more wallet friendly than an entire set of Nickies.

The pistons are at the present being treated to a dose of friction reduction, and thermal barrier coatings to further reduce friction and increse efficiency. The rings we will be using are still up in the air, but I KNOW they will NOT be Total Seal variety. I may go with a Childs and Albert top ring- Time will tell on that one.

Camshaft and heads
The cam and heads are by far the biggest keys to this combination. I have plotted 50 different cam masters and have found a few that are promising. I am waiting for len to flow the heads before we make the ultimate choice on camshaft. One thing is for sure it will be something that will utilize a single spring to control the odd size valves that are going into these heads.

Speaking of the heads, Len has based them off of a set of 1.7 "Q" castings and is already in work on their modifications. We are keeping the port size down to really add to the overall velocity which is paramount with this combination to have excellent low speed performance as well as incredible midrange efficiency and throttle response. Len can say more about the heads if he likes but with the "shadow" I'm sure he'll be conservative.

Intake system
Based on SDS EM-4 electronics and may incorporate direct fire ignition as well for ultimate tunability in the midrandge and at peak torque. I am making some definite changes to the DTM on this engine to incorporate a common plenum that will reside in the location that now houses the oil cooler housing. The oil cooler housing is being relocated to another area that I'll cover in the cooling system specs later in the outline.

The FI particulars are still up in the air as I wait on some numbers from another source as well as camshaft particulars.

Exhaust system
No doubt that for this engine we'll be using a Tangerine Racing system! The 4-2-1 design benefits mirange power and efficiency and thats exactly what we need. Len, chris and myself all agree that the system should be made from 1-1/2" tubing instead of 1-5/8 as standard. After all this engine will be so efficient that it won't have many exhaust gasses that won't be getting burned in the chamber!
Chris has never made a system from tubing this small, so thats neat in its own...

Cooling system
DTM (imagine that) in Silver Carbon fiber. I will be trying different combinations of drive ratio with this engine in the car to find the one that best suits the operating tep of the engine. I also plan on running a 356 fan with a slower than normal drive ratio to see how it works compared to the standard TI wide fan. With the small bore and super friction reduction coupled with the high geared tranny(low operating speeds) I am sure that an external oil cooler will not be needed to cool this baby.

I have been working on "DTM Version 2.0" for a few weeks now and have some changes in the works to relocate the stock TIV oil cooler back to the stock location!!!! This will create a cleaner look and not effect the head coling efficiency of the engine. I am only doing this to free up space behind the shroud to add a provision for a center mounted common plenum for my future EFI equipped engines. This will be prototype #1 for the modification.

Compression Ratio
"Bump it up and this one is gonna thump!" It'll be enough to make the Low CR Berg fans hate me even more! All I'll say is that it will have "Plenty" of CR- The lifeblood of efficiency!

Transaxle
Based on AH code TI IRS gearbox with 3.88 R&P and a super tall set of gears including a custom mainshaft with taller 1-2 gears as well as taller 3-4/ With an engine that cools this well and has this much efficiency I want to create a gear stack that will put us at 80 MPH @ peak torque! I'll have to wait till the engine is dynoed to finish the gear selections after we get the tires mounted and etc as well. Peak torque is the point where any engine is it's most efficient and since my target is a cruise speed of 80 MPH.

So, there ya have it in a nutshell!

So, what is the overall goal?? To work on this combo to the point tht wewon't need Nikisil cylinders, friction coatings and etc to create the efficiency. I want to create this combo for the incorporation of another "Kit" to the Type 4 Store line up and I doubt we will be assembling any of these other than for R&D purposes once we get the combo all figured out.

Charles and I will be creating a page on the site to go over this build up in detail and it is looking like the project will be the subject of another RAT video to show how to install our EFI system step by step into a Bug of any year.

This project is incorporating every facet of the awesome network that we call the "RAPP" or "Ring of Aircooled Precision Performance" that consists of Aircooled Technology, Hoffman Automotive Machine, LN Engineering and Tangerine Racing- Together we'll make this one humm dinger of a project and will create an engine to battle the high cost of fuel these days while maintaing a fun to drive, zippy, reliable aircooled vehicle!

This will be great! Now we can go places and the girls can ride together while we drive how we want. An extra car would have come in handy on the last cruise. That would have made what, 4 RAT engines there?!

Bert

A Silver GL 1303 vert for Beth. She will love driving that. Good GL looks, great handling/braking, a drop top and a super efficient RAT type 4. Great fuel econ. and enough power to spank "Ricer Boy". Sounds like her "Silver Bullet" will be sort of like a "Varmit Round". Your 3.0L is like the 375 H&H and her 2L being a 222 rem.
Hmmmm throw in a blue bottle for fun and it's a 220 swift
Remove some weight from the car and it's a 17 rem.

Aircooled advancement at it's finest. Ferdinand would be proud.

Thanks guys!

I was pleasantly suprised when she found this car and decided that she wanted it. It didn't take long for me to "convince" her that it really could use this engine for more reasons than just fuel mileage.

This weekend we are going to work on the floorpans and install the disc brakes, Porsche wheels with tires and then let her drive it for the 2 months it's going to take me to finish the engine, EFI system and tranny.

Jake,

I am opening a store.. can you email me all the specifications on your engines?



Good job Jake, one day when I am rich and famous... well, maybe not, but I'd settle for well off and largely anonymous, I will be calling you to build my beast. I'm gonna stuff one of those in my 70 bus one day with the help of a welder and some other stuff to handle the rear cradle.

LOL, but you have to get the current beast tuned first! LOL

You mean the guts you just finished for me, or the 2332 Squishy?

I'm watching the FedEx guy circle the block looking for my house right now on my surveillance cam. He's dropping off my DRD heads for the bus engine. YAY!

LOL Back and forth.. the damn address is RIGHT out there... what a goob.

SWEET!

Mr. Squishy is about done now. I just have to wait for my 57 idles, my timing control, and get the last timing tweak in and we're ready for the rolling road. I know my jets will be about right, but the timing will have to be played with so I wanted to get a timing control to allow me to play while holding at certain loads and RPMs. Gonna get as close as I can with that. I am currently getting about 22 MPG until I can get my jets right on. Should go up a little. Course I got a really heavy foot. That does not help.

I just can't imagine 50 MPG.. that's amazing Jake. Keep up the good work.

50 is the goal.... I don't know if we can nab it on the first quest but I'll damn sure try!

Hell, Len is more excited about this project than I am!

Jake-
I would gladly wait a litte while longer for a DTM 2.0...I REALLY would like to run the oil cooler in the stock location, my ONLY issue with the DTM as-is is the oil-lines to the cooler (cosmetic...am I picky?). Last I heard my DTM would be ready in pretty soon..I'm in no huge hurry, seeing as how I may be waiting for the 912 tins anyways.
What's the time frame on getting maybe a..pre-production kit?
Same price?
Kick ass!
Bob O
68' 912
Washington State

Jake,
I will be happy to provide a partial Sponsorship on this project. I have often thought about adding a smaller version of my header but never got around to the development. This is a perfect opportunity!
Expect an email from me to provide you with some particulars.

914 Ghost,
It may be well over a year before the DTM V 2.0 is ready for sale. It will have a ton of testing needed before I will even contemplate selling one to an individual.

Chris, Thanks for the help on the project, Beth and I appreciate it very much.

This is going to be the baddest GL vert ever owned by a chick!

I just got off the phone with the Carbon Fiber shop and they are starting work on the complete set up in silver carbon this week.....

The Silver is one of a kind and there won't be a second set.

You know what this is all about guys. It's simple. Beth wants some decent gas milage, and Jake wont stand for her driving around in some water cooled car!

Ron