Engine just before removal (with twin Dellorto DRLA40s and Mallory ignition). Very untidy wiring - installing EFI will give me the kick to install the wiring neatly after temporarily fitting it 3 years ago!
Here is the crank trigger a wheel a friend designed and had laser cut for me. The missing tooth is still present, once I have fitted the crank trigger sensor.
I will use Alfa Romeo 145 1.7 16V boxer throttle bodies. These have 40mm bore at the top, but are of an oval shape at the bottom.
The friend that designed the crank trigger is making me the flanges for the head and the throttle bodies.
Q. Hi, I'll follow your setup, I'm also a vw enthusiast. I had heard about throttle bodies from alfa engin, but I was told that they had the idf pattern on the bottom. That's why I also picked up one of those 16v engin equipped with oval-shaped bodies, and seeing this disappointed me. I'm curious to see if you can get hp from those with custom manifolds. Did you dyno the engin before evolution? -could be pretty interesting. Nicolas
I had the engine dynoed a while ago, but due to finding poor quality head work (by a professional - one of the only things I have paid good money to have done..) the engine has been stripped down to be stroked (2145 - 74x96) and have the heads rebuilt to a better spec.
Q. what kind of crank did you choose to replace the original 71mm crank? I have a pretty good contact for good head work in Paris (f.i. type 1 1956, web 86b dynoed @ 143 hp with modified 040 40x35,5 heads and weber 40 idf). What kind of heads do you have?
I'm attempting my first type 4 build and I'm using Ducati 748 916( Weber ) throttle bodies. Complete with TPS linkage and injectors £25 a pair on E-Bay. They are about 45 mm choke size. There is a version that appears from time to time with dual injectors which is off the later bikes. The current system is very tasty and uses upstream injectors firing straight into the TB. They have appeared on E-Bay at about £50 a pair. The spacing is such that IDA manifolds are needed as the TBs are handed and open opposite to each other and the injectors make them separate too wide for IDF manifolds. ( You'll see what I mean if you examine a pair )
Hello Mike, I'll try to locate the weber TBs you are talking about, they seem pretty interesting, mostly because of dual injector. You meant 2 injectors for one cylindre, didn't you?
Do you have specs of your T4?
Wed 24 Jan
If you have a My Ebay page go to search and key in ducati throttle bodies. There are no dual injector ones on offer at the moment but they come up from time to time. I bought a pair for £20 but they can go to silly money - the last ones I saw went to £102 for the pair. I don't think they are really necessary as the single injector version is good for more than 50bhp per cylinder in the bike. Make sure that any you bid for still have the bell mouths as well, some people tend to sell these separately. The TBs can be attached to an IDA manifold using a mounting plate about 10-12mm thick. The TBs plug into holes and locate with O rings.
My engine is still at the parts gathering stage but it is to be 78X100 ( 2450cc, Porsche barrels ) JE flat tops, Engines plus twin plug COP heads with 11.5 CR, Webcam 86C, dry sump. Loadsa poke - I hope !!
I found some on ebay.de. 169€ for 2 DUCATI SP5 888/851 is too much compared to aftermarket solutions, especially when I know that I'll need 4. I'll keep on watching ebay.
It willll be rather difficult to fit Porsche barrels on your engin, they are really short. You'll have to use shims under cylinders, but the'll be ~1cm high and won't have any fins. Maybe you should reduce stroke, as we can't shorten rods much more than stock value. At least take Nikasil Porsche barrels and keep me in touch!
Heads seem pretty interesting, do you have further informations about them?
I agree with you about the price but be patient, the stuff does keep popping up on ebay, allow £100 for two sets and stick to that if you want twin injector TBs.
I decided on the Porsche barrels after seeing a posting some time ago by "Wally" on the Shoptalkforums, Type 4 section. He used the barrels and pistons and modified the piston crowns and rods in an otherwise mostly standard 914 engine to give about 155bhp on carburetors. I've checked the cylinders and they could accomodate a stroke of up to 98mm
I have access to a really good machine shop so spacers are not a problem though head studs may be.
The heads are from a german company near Cologne and are very pricey but allow very cheap Type 1 exhaust manifolds in large bore sizes. Twin plugging is an option so this is why I'm interested in the VEMS to use in 8 cylinder lost spark mode to drive the twin plugs/COPS