Upgrading to throttle bodies

[Sparkymart]

Hi all sorry to start another TB thread but there is a couple of things I would like to clear up so here goes..

I'm looking at maybe upgrading in the new year. I'm going up to the classic car show and auto sport and want to know what to look out for

ECU.. Omex, emerald, megasquirt. Megasquirt is in kit form so is that build up from component level? Or just making leads up etc, big savings over the other two but is it as good?

Throttle Bodies.. I'm thinking bike ones just for cost

Swirl pot.. If I was to get a sump welded to the bottom of my tank and maybe a baffle or two fitted and a fuel return would that be OK

I've currently got 45's with a weber alpha 3d ecu and I've got a flat spot,The local RR guy said it could be 4 progression holes and I need 5 but he needs to have the car in to check for sure.so I'm thinking if I need a rolling road session get it done on fuel injection

And finally what sort of money would my 45's and inlet manifold and ecu etc be worth

Thanks Martin

[Kingster]

I'd say depends on how much you have to spend, as none of it is cheap!

 

If you went for Jenvey or Omex DCOE TBs you could retain your DCOE inlet manifold (I believe) which might offset the cost of Bike ITBs and a suitable manifold & inlet rubbers to suit them. But don't forget the added extras such as throttle linkages and TPS etc for the Omex/Jenveys that might come 'free' on a set of bike ITBs anyway.

 

You can get a MegaSquirt built up or a MicroSquirt if you don't want to do the kit thing - but honestly can't advise as no experience of these. Only thing I would say is to ask whoever you plan to use for mapping what ECU they prefer, as you will need to get it mapped regardless.

[TrophyJem]

I run a diy (built by me) megasquirt on my duratec.

It runs great and seemed easy enough to map although I had no other mapping experience so I can't compare.

If you can solder electronic components and are confident in your skills then go for it, if not then you can buy ready built.

Dan at ST engineering does a bike throttle body conversion kit for many engines. I have no experience of these as I went for a second hand set of AT Power bodies but I've read good things about Dan

[Sparkymart]

Thanks guys I didn't realise you could bolt TBs onto the weber inlet, I was looking at the bogg brothers ones and there is a couple on fleabay around the£200 mark or a kit for around £699 (excluding ecu) I'm not to worried about the cost for the right thing but I hate wasting money I would sooner wait 6 months longer to get what I want, but is bike TBs are on par with jenveys etc, for a lot less money and no major draw backs than that will also sway me.

I can also offset money from old set up to fund the new

So I reckon first us to find out what my local tuner can work with

[Pistol Pete]

If you use a golf gti mk2 fuel pump its own sump, you can then use your existing l.p. pump as a lift pump and supply the fuel to the house pump/sump, therefore the only mod to you existing tank is a return feed.

[Dave Eastwood (Gadgetman) - Club Chairman]

Ecu; unless you have a need for some special ecu function, they're all more or less on a par at this end of the market, and that includes the ready made Mega Squirts. In truth, the biggest difference between most is probably the software, but again, if having it mapped, that's not the highest on your priorities. Cost aside, I'd pick whatever my favoured rolling road operator was most comfortable using, and ideally one with a good base map for the engine I was going to be using it on.

 

As for the TB's, I suspect, performance wise, the only thing splitting the bike models and Jenvey/Omex etc is probably the quality of intake manifold design. And even then, if it's a manifold originally developed for Webers, it may be compromised in its own right!

 

So unless you're building a really highly optimised engine, I wouldn't worry about it!

[Sparkymart]

If you use a golf gti mk2 fuel pump its own sump, you can then use your existing l.p. pump as a lift pump and supply the fuel to the house pump/sump, therefore the only mod to you existing tank is a return feed.

Hi Pete just looked on Google at the golf pump, the outlet from existing take connects to that small tank feeding the pump is that right? That makes life easier

[Sparkymart]

Dave

As far as I know I've got a standard black top and it's plenty quick enough for me. My local tuner said it should be around 160 bhp with 45's but as it's never been on rollers it could be anything.. It's the flat spot(feels like no fuel for a second then takes off) I want rid of when I hit the loud pedal, not max power

[Pistol Pete]

Dave

As far as I know I've got a standard black top and it's plenty quick enough for me. My local tuner said it should be around 160 bhp with 45's but as it's never been on rollers it could be anything.. It's the flat spot(feels like no fuel for a second then takes off) I want rid of when I hit the loud pedal, not max power

Best just do lots of searching then, not a Webber man but lots on progression.

[Sparkymart]

Anyone come across race systems ecu's...?

[Dave Eastwood (Gadgetman) - Club Chairman]

They may be the best thing since sliced bread, but the deafening silence speaks volumes for the response you'll get on the Boardroom to any questions on installation, set up etc.

 

As said though, the best ecu, all other things being equal, is the one your rolling road operator is most familiar with. Or put it another way, do you want to pay someone, possibly in the region of £75 an hour to learn a brand new piece of configuration software and to get to grips with any little foibles in how the ecu works. Or would you rather have someone who knew all the keyboard short cuts and could get the best out of it in the shortest time period?

[corsechris]

Concur with all that's been said, just like to add a couple of extra comments. Don't get carried away with TB size. If you plan on keeping the engine stock and want the best overall driveability then something like GSXR600 size will work really well. May possibly compromise the last few bhp but will give great throttle response. Have them on our 2l silver top and that makes 169bhp.

If you go for actual bike TBs, beware of the potential minor hassles around slight throttle mapping. Make sure your chosen ECU allows you to define your own throttle position to load tables (assuming you configure for Alpha/N). Most modern ones do, but be aware.

Those Golf pump/filter/swirl jobs are great. Used them before and they work great. Have one on the westy, mounted in the engine bay, just added a new line for the return. Kept the original LP pump etc to feed the golf unit.

Once properly mapped, you really won't regret doing it. Transforms the car for 90% of the Rev and throttle range, the 90% you use most of on the road.

ETA. Just for info, stock silver top on GSXR600 tbs that I DIY modded to fit a DCOE manifold. TPS that came with the bike TBs is perfect for most ECUs, Emerald M3DK (an old one, hence my comment about being able to adjust the throttle mapping), Golf swirl/pump/filter thingy, generic 3 BAR fuel pressure regulator, idle air control valve from a K series, throttle linkage that came with the TBs, injectors that came with the TBs, DCOE pattern filter backplate. Used the same setup on both the Xflow then the Zetec.

[Kingster]

My silvertop is on gsxr1000 42mm itbs and has been on two different dynos (one by previous engine owner) and put out just over 168bhp on both occasions. Manifold is off an st170.

So I reckon they do the job nicely.

[Paul Hurdsfield - Joint Manchester AO]

My 2.0ltr zetec on 45 webers with Alpha 3d igniton  and 5 progression holes puts out 163.5 bhp 

One thing the rr operator told me was something they discovered by accident on an Escort with the same engine setup.

On top of the carbs there is a cover with a wingnut over the jets, if you leave it off it greatly reduces the flatspot that most zetecs on carbs have.

On our recent 1881 mile European tour i regularly swapped between cover on and cover off and the difference was quite noticeable

Try it and save yourself £2000 - £2500 

[1959grantura]

Been reading with interest and would like to ask the question

With the price difference there must be gains to installing and setting up the car throttle bodies (jenvey/omex) compared to these bike carbs set-ups you see for around £700 ?