OLD rover efi in skip and holly 4 barrel instead?

[wade69]

350i Had enough of my trashy LUCAS EFI thinkin of junking it all and goin with 4 barrel carb on hi flow manifold, any one got experience of this !!! plaese

[GreenV8S]

quote:350i Had enough of my trashy LUCAS EFI thinkin of junking it all and goin with 4 barrel carb on hi flow manifold, any one got experience of this !!! plaese

Had a beaut once where one of the floats jammed under acceleration, pumped neat petrol into the manifold, flames two feet into the air. Goodbye air filter, good job there was already a hole in the bonnet! Hollys, doncha love 'em?

[Graham]

Im thinking of going a diferent way, juncking the lucas ecu and the airflow meter and going for an emerald ecu...

[mgv8]

Hi
Go for the webber 500. Get it form the USA it will be £100 cheper.
Get it set up, it will run as soon as its on but will need difrent needles for you setup.
Thay work very will are easy to setup. It will not be as refind as the injecton.
I have a MGB roadster with 222bhp 223lb. Carb is nice but second chokes dont come in to smothly.
But fun.....

[phil hill]

I agree with Graham, junk the Lucas ECU and fit something that works and you can play with instead. Don't know which version Lucus is fitted to Tiv's, single or twin plenum ?? Anyway, Emerald are getting better, there support wasnt so good initially, Webcon (thats Webber to you and me) Alpha Plus is good, if pricey or Luminition. Aussie company Motec used to do a direct replacement for the Lucas but don't know if they are still around. On the replacement carb front consensus of opinion is the Webber/Offenhouser or Webber/Edelbrock combination being best. Mind you, I'll swap you my twin HIF 6 SU's if you like.......

[phil hill]

Ok, so I thought of something else........

Holley 390cfm is smallest available, and unless you have a modified 3.5 this will flow too much air (rough rule of thumb is 2 to 2.5 cfm per HP, so 160-195hp potential with 390cfm). Ok, I admit that manifold will be greater restriction than carb, but that's the accepted rule of thumb when sizing carbs. More of a problem on the MGB V8 is getting the air cleaner under the bonnet/hood. Webber 500 kit is widely accepted in MGB V8 and Cobra replica world as the best for ease of mounting, air cleaner location and size, calibration and economy. See RPI link in the "oily pages" for full story.

Phil.

[rbfisher]

I've got a spare Lucas 4cu ECU if you want to buy one that works. I used it in my 350i while the old one was being repaired and it ran perfectly - much more power and smooth acceleration.

Cheers,

Richard Fisher

[350matt]

I can certainly reccommend going the Emerald route as I've got the kit on my Wedge, however a carb is fantastically easy to set-up although won't yield the same driveabilty, mid-range or economy as the injection route. Another reason I kept injection was it was in fact cheaper to fit the aftermarket ECU (£600) than replace the manifold, fit a weber etc. In summary; the carburettor is one of the best ideas ever but injection will beat it after a LOT of setting up.

Matt

[Graham]

quote:
I can certainly reccommend going the Emerald route as I've got the kit on my Wedge, however a carb is fantastically easy to set-up although won't yield the same driveabilty, mid-range or economy as the injection route. Another reason I kept injection was it was in fact cheaper to fit the aftermarket ECU (£600) than replace the manifold, fit a weber etc. In summary; the carburettor is one of the best ideas ever but injection will beat it after a LOT of setting up.

Matt

Any chance of a copy of your ecu map ?

G

[350matt]

No problem,e-mail me for details.
But you should bear in mind that it'll only get you going, your engine spec is bound to differ from mine and the map will need tweaking appropiatly.

Matt

[cirks]

only just noticed this thread but is of interest as my potential 4.5 to 4.8 upgrade is likely to end up with me junking the injection and going for the Weber 500. Any other thoughts or comments welcomed in addition to those below.

[kevinday]

I personally would only go for injection, the benefits far outweigh the drawbacks of initial set up. A carb will generally give you less overall performance (it will have gaps in the range) and worse fuel consumption.

[boosted ls1]

I've had a few large rovers up to 5.4L. They all used a Holley carb. I found the 390cfm was far to small on a 4.5l even with the choke plate removed. When I fitted a 600 d/p the 4.5 was transformed especially on the bottom end. When I fitted twin turbo's I kept with the holley for 10 psi boost then went to Motec efi. The efi is better once it's all sorted but for normal aspiration and diy then the carb is the way to go because you can tweak it at home or locally. I like holleys but have heard very good things about the Carter/Webber 500 sitting on an Edlebrock manifold. I sometimes miss the carb!

[2 Sheds]

IMO going from injection to carbs is a huge backward step, If your really keen to tweek things yourself you could down grade to Flapper injection, but even that seems daft to me. Sure enough 4x twin downdrafts will provide plenty of BHP but still crude and costly.
Tim

[boosted ls1]

2 Sheds said: IMO going from injection to carbs is a huge backward step ]/quote]

I agree Tim, in many respects it is a backward step. That's why I got the Motec. Properly set up efi offers faultless performance and good emmissions etc. However if you have a retrofit system or have changed the engine specs significantly then the efi can be a pain in the butt to sort out and costly as well. Most people can tweak a Holley or similar plus if you have a cam change or capacity increase the 600 Holley or webber 500 would still be suitable and tweakable at home. Don't get me wrong, I love the Motec but who really needs sequential management and individual cylinder adjustments. I can have it but don't really want it. With a V8 I can afford to give away a few lbs/ft and bhp. I only use the efi because carbs have limitations with forced induction otherwise I would probably go straight back to the 4 barrel option. It's up to the individual. Does he want to fiddle about with a laptop or screw driver. My guess is that Wade69 could be in the states. Across the water they don't especially like 'The Prince of darkness' or any of his products. A 4 barrel and intake may cost around £500 ish, it's cheap and simple. Aftermarket efi is around a grand to 3k?

Incidentally, does anybody know of a dizzyless efi with coil drivers for the v8 for under £1k? A friend needs one.

[2 Sheds]

Yes i,ve found that the hotwire injection is not so popular in the states, i have customers with newish Morgan V8s running flapper systems.
My original point was that if you already have an injection system on the car thats working and you upgrade engine, its worth upgrading the injection to suite, if hotwire £350 for a chip & £375 for porting & upgrading the induction & rolling road is always a good idea (£250 ish but this could also apply to a carb set up).
I agree that if your starting from scratch, the carb route is going to save you a fortune, and may be the best solution.
Tim