Quad Downdraft Emissions?

Ian Anderson · Post by **Ian Anderson** » Mon Nov 09, 2009 1:56 pm

I've been offered a set of quad Dellortos and manifold for a reasonable price

Does anyone know if these would be able to meet the 1990 emission requirements of the UK
3.5 and 1200?

They'd look the business in the GT40 but only if the car can stay on the road!

Cheers
Ian

kiwicar · Post by **kiwicar** » Mon Nov 09, 2009 2:25 pm

Hi Ian
1990 is pre compusory Catalitic converters isn't it? If so a set of Dellortos should be able to meter fuel accuratly enough if set up right, they are alot better than a 4 barrel as there are more metering circuits. also as it will be l choke pre cylinder you are much less likley to get fuel dropping out of suspension and mucking things up at Idle the way you do with a 4 barrel.
Mike
PS I take it you contacted the chap on Racecars?

Edit, just checked, it was 1992 things got nasty with Cats etc, so with the carbs in good condition and set up right I recon they should get you through.

Ian Anderson · Post by **Ian Anderson** » Mon Nov 09, 2009 3:10 pm

Yes that is correct

He took a while to reply and knows very little about them like jet sizes etc.

Good to hear that the emissions may be OK

Really don't want to spend the money and then have to revert to EFI

IAn

kiwicar · Post by **kiwicar** » Mon Nov 09, 2009 4:03 pm

Hi Ian
from what I remember Metros and various Polos and Golfs were running carbs right up until Cats became mandatory, I think a couple of Korean and japanese cars were running Carbs and Cats, though not for very long and they had Lambdas and electronics on the carbs to try and avoid bunging up the cat!
If you go down this route I think you will have to become a bit of an expert on them as I don't think there are many people out there now who have worked with them recently. They do look fantastic under the rear screan of a GT40 though

Mike

Ian Anderson · Post by **Ian Anderson** » Mon Nov 09, 2009 4:15 pm

Or do I get an old block that I can date as per 1975 and swap it for the engine in my car?

And biuld up an engine that only needs a visible smoke test?

Perhaps build it using the heads, cam, lifters, heads crank and perhaps even the block) of the current engine?

Ian

kiwicar · Post by **kiwicar** » Mon Nov 09, 2009 5:20 pm

I thought smoke only was pre 86?
I'm sure someone on here is running a '90 block on carbs, if you can get a 4 barrel through emisions you will get a set of dellortos.
You with an AFR meter and a laptop to log it with, a good book on the carbs and a pile of jets rods and emulsion tubes you should be able to do it. The ability to log it that you get now must make it possable

Mike

topcatcustom · Post by **topcatcustom** » Mon Nov 09, 2009 6:11 pm

Ian, how about getting some old downdrafts and gutting them, keeping your injection but using them for throttle bodies? Best of both worlds then!

Ian Anderson · Post by **Ian Anderson** » Tue Nov 10, 2009 6:55 pm

I asked the same question on the GT40 forum and they seem to think that the JE102 cam will cause reversion problems and mean it cannot be "got" within emission requirements

Perhaps the gutting and throttle bodies is the way to go - just have a problem wih space on the crank pulley for a trigger wheel there isn't any!

Perhaps the pickup etc can be mounted inside a dizzy

Ian

CastleMGBV8 · Post by **CastleMGBV8** » Tue Nov 10, 2009 8:45 pm

Ian,

The dizzy can be use as a trigger it just needs to be locked, alternative you can fit the trigger wheel on the rear face of the crank pulley, but that would mean more work with a GT40 with the access problem for removing the pulley.

Kevin.