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crossflow on throttle bodies

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Has anyone on here fitted throttle bodies to a ford x flow engine. I am after a few tips eg fuel tank return,swirl pot or not and what is the best fuel pump set up. The itb's will be jenvey with emerald m3k ecu.

Thanks.

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Well I've fitted R1 throttle bodies to a Zetec SE engine and got that to work with an Emerald ECU, so know a little (couldn't afford the Jenveys and they would have stuck out of my bonnet which I wasn't keen on). I paid £40 for the Yam R1 TBs on ebay with injectors and about £300 for a custom manifold to be fabricated. The TBs came with all the wiring and mated directly up to the Emerald - all straightforward stuff.

Hardest part without doubt is making the inlet manifold. Mine had to go from a circular shape of the Yam TB to a kidney-shaped port of the Zetec SE. I started to fab something, realised that it was way beyond my skill level and immediately entrusted the whole task to Nigel at Altiss Engineering, who I can't recommend highly enough. He then fabricated a beautiful inlet manifold out of TIG-welded alloy (work of art it really is).

I then used the injectors on the Ford engine, and the injectors on the bike to fuel it (the Emerald brings them in progressively above a certain rev range). Fuel pressure reg is from the original bike.

I use a combination of pumps. Firstly a low pressure high volume Weber type unit mounted in the front to suck up fuel and keep the swirl pot topped up. This swirl pot then feeds a high-pressure Bosch car fuel pump to pressurise the fuel rail (s) via its lowest outlet (SBD do a good swirl pot plumbing diagram). The upper-most hose on the swirl pot is then returned to the fuel tank. I did this on my specific car as it uses an MG midget carb tank and had lots of problems with fuel starvation.

With a Westie, they do quite a nice fuel tank with a built-in swirl pot and one high-pressure fuel pump mounted low down - that's probably the easiest route to go for you and would avoid the need for

Finally I got the whole thing running roughly (following the Emerald instructions) and then took the car to Dave Walker at Emerald to get it set up properly. Unless you're an electronics genius it's virtually impossible to get the car mapped as well as a pro. After fitting cams to this otherwise stock engine I got 160bhp on the rollers (100bhp from Ford).

The key bits, I think, are to get a decent inlet manifold made up (yes, you can get slightly cheaper steel ones made, but they're not a patch on a custom alloy one) and to choose a TB set up that is roughly spaced like your cylinders if possible - saves a lot of mucking about messing up the TB linkages and having to fabricate fuel rails. Jenveys are probably one of the best.

Chatting to Dave Walker he reckons the diameter of the TBs is nowhere near as critical as carbs, which gives you lots of options. I'd read loads of rubbish about my Yam R1 TBs being too large for my engine and lots of nonsense about 'poor low speed air flow', but in the real world they've been fine - pulls cleanly from 2K revs, gets into its stride at 3K and then howls round to 8K - nice!

Also get it set up on a rolling road - best £200ish you'll spend and will saves months of guesswork.

With the ECU, TB, inlet manifold fabrication and rolling road set-up, I got the whole thing running for around £1000 ish.

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There's loads on here in the archives on converstion to injection. Xflow has been done, but right now for the life of me I can't remember the name of a very helpful chap on here who had done it and sent me a load of advice. I'll look in my email at home tonight and let you know later. Once you've run a return line front to back of car it shouldn't be too hard (no harder than any other engine). If I'm not mistaken you may be able to run Jenvey's on your current manifold (assuming you're running twin 40's) - could be wrong though. If you're planning an Emerald ECU then Mr Walker will be able to set you straight on that.  I'll be interested to see how you get on - I've just put the return line into my car with this future conversion in mind (happened to have diff, gearbox & engine out of the car so seemed a good time to do it). Good luck.

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I was going to use bike carbs but i was not sure what size i needed as it used to run 48's. The tank with built in swirl pot looks good but i have read a few threads that say you can still get fuel surge when hard cornering. Where is the best place to position an external swirl pot?. One more question,if the low pressure pump supplies the swirl pot will the pump run constantly as the pot has a return back to the tank?

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Think you need a restriction in the retun line to prevent the pump running all the time.

Must be a heck of a crossflow to run on 48's! However does that mean you can put 45 t'bodies on the same manifold?

Have a read here:

link

It's not a crossflow but Ian's explanation of how to do things is very good and clear.

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Don't bother with a swirl pot, get the fuel tank properly modified with an integral swirl pot.

I put a seperate pot in, with a lift pump, and the resulting hornets net of plumbing and wiring looks a right mess, then just to add insult to injury Chaz found somebody who can put a nice big 1 litre swirl pot on to the bottom of the tank with an integral pre filter for not much more than I paid for the external tank.

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check out RICH P on OLD SKOOL FORD, he is a mate of mine in Redditch running Jenvey TB's on a 1780cc cross flow in the OLD SKOOL FORD drag racing championship

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Jenvey DCOE throttle bodies will fit on the same manifold as DCOE carbs. That's their raison d'etre...

You would need a restrictor in the feed from the lift pump to the swirl pot to prevent the lift pump running flat out. The return feed from the pressure regulator back to the tank is at atmospheric pressure or whatever pressure is left. It won't be much...

Best place for a swirl bowl is dead centre of the fuel tank bottom face. Cut a 2" (5cm) hole in the base of the tank. Turn down the edges so that they are proud on the *outside* of the tank. This gives you a vestigial "baffle". Then weld the swirl pot over the hole, and add a -6 fuel line connector. That's what I've done on mine. The swirl bowl itself is a good 6" (15cm) in diameter. I forget the depth :blush:

I also added a return to the top of the tank right above where the swirl bowl is. Mods, including 3 off -6 fittings (feed, return and breather which is out of sight) cost less than a lift pump and swirl pot to buy...

4873.jpeg

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The car came with a race crossflow that has all cosworth internals,full race head,264 cam,cam gears,dry sump etc. Just had it rebuilt with 262 cam and hot rod spec head,so i thought i would treat it to some throttle bodies and emerald set up. The battery is located in the back so there is limited space for pumps ,swirl pots etc. I am going to look into those tank mods,saves on the plumbing.

One more thing.....45's or 48's ?

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Converted my 1852cc Xflow to injection in 2003 (quite radical back then). It gave 185bhp+ on 45's if that helps your decision.17023.jpeg

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45's. It's normal to reduce the size of the "chokes" when swapping from carbs to TB's...

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