CIS to EFI converter

Hey Til, anything going on with this exciting project?

 

Doing the same for my QV at the moment. Collecting parts and planning.
What is the diameter of the inlet side of the Thema 8.32 manifold runners? (the side towards the throttle bodies).

I have a set on the way from Germany and I've acquired a couple set of Hayabuse throttle bodies.

THANKS!!


Jeff Davison

 

Thanks!

The Hayabus throttle bodies measure 2.198" O.D. at the outlet. The I.D. measures 1.652", but it is offset. There is also a cutout in the body for the injector.

Luckily, if I use the stock Hayabusa T.B. to head rubber boots, they should mount up directly to the Thema 8.82 gen 1 manifolds after re-spacing. (the gen 2 manifolds have an unwanted flange on the t.b. end). The boots are molded and the inner hole is offset to match the body and also makes for a smooth / faired trasition between the two, so there won't be any turbulence because of the empty space between and directly under the body the T.B. if just a piece of straight walled tubing were to be used to connect them. The lower part of the boot that connects to the head / manifold is stepped down to fit. Looks like an easy fit, but will know for sure once the boots arrive in my hands.

Spacing on the Hayabusa t.b.'s are the same as the GSXR 750 and 1000 @ 80mm.
The spacing on the 308QV is 94mm, so I can use off the shelf spacers of 9/16" length (1/2" o.d., i.d. for a #10 screw size) between the throttle bodies (requires 9 per bank) and longer 14" (vs 12") bolts (requires 3 per bank), to hold the assembly together.

I'll blank off the Hayabuss injector ports, tho I'll make it reversable if I ever want to do dual injection) and use the Thema 8.32 ports for the fuel delivery. I'll have to fab up fuel rails.

One thing left will be extending the paddle/lever arms between the bodies that actuate / connect the simultaneous operation of the butterflies.

I found some (relatively inexpensive) velocity stacks for these. Most of the stacks I've found were from $200 for 4 to $$330 for 4 billet. Yes beautiful but pricey.
Sudco / Mikuni offers spun aluminum stacks for their RS series of smooth bore carbs ( 55mm dia. inlet spigots) that I've found for $60 for 4. AND.... they are available in 15mm, 30mm, 50mm and 70mm heights. The inlet of the Hayabusa bodies O.D. just happens to be 55mm, so they should just clamp on and fit.

Since I'll be using the engine (eventually) in my Stratos replica track car, I may or may not be worring about an airbox..Maybe just use some inlet screens.



JD

 

Jeff,
I think the eassiest way to fix the tabs is to tack weld somthing on. The fancier way is to clamp on an extension.....I would weld.

You have an M800 don't you? What are you doing for load sensing? TPS with barometric correction using the MAP to atmophere? Map to a plenum of some kind? I had a friend design up a board that can hold up to 12 MAP sensors and pass the lowest pressure to the ECU. I'm going to try TPS with baro correction but with what should be a true MAP signal....I think that will yield the best of both worlds between TPS and MAP tuning but for a track car maybe all you need is the simple TPS with baro corr.

 

I've seen a few ways to get the extension length need, so I really don't see any real problem. I've seen tabs welded on and I've seen tabs bolted with small hardware and I've seen the tabs riveted. I think welded steel would be the most reliable, and straight forward seeing I have a tig welder on hand..

Haven't gotten that far into the replanning of the f.i. setup as it was going to be sc's originaly, so a rethink is in order. I have a flywheel mounted "chopper" wheel from Kermit (Durable 1) that I acquired when he was still above ground. TPS will most likely be the one on the Hayabusa tb's. I've been following your MAP sensor PCB project and that looks interesting, and I've seen some fi conversions using a central manifold block with vacuum take offs from 4 tb's, and I've seen a manifold block with vacuum takeoffs from 8 tb's.
It will be while before I have to finalize that decision, but I really watch your PCB development with great interest.

Beside the crank trigger, I have a cam trigger chopper I can adapt to one of the heads distributor drive to get sequential injection, but I think I reall don't have to. For my needs just batch injection and wasted spark should do me fine.

Yep...Have the Motec M800. Glad I bought it when I did and from whom I did as the price is just over double nowadays. I still have to buy the USB-CAN adapter to link my laptop to the ecu.

Jeff

 

What is the advantage of the ITBs over something like this?

http://ferrarichat.com/forum/showthread.php?t=277339

thanks,
Aaron

 

It's realy small and thin....you'll need a copper backing block to tig it nicely I think....or spot both sides with the mig.

All the options will work. If you use a small plenum reading of 4 cyl the signal will be about 1/2-2/3 actual....I think it would be more like 1/2 with 8. You are only using it to correct the TPS so I don't know how much it matters for a track car. I'm a little worried about off-idle with big TB on the street and I'm thinking a good MAP signal is required.

You will make a bit more hp and burn less fuel with sequential. Also I'm not sure if the cylinder trims work if you are running batch....the trims can be very helpful.

 

Coolness

You can get a bit more flow out of the ITBs, particularly if you have other mods as well.