The V8 Owners Forum -

Posted: **Fri Feb 27, 2015 6:49 pm**

I'm intending changing my SD1 EFI engine for a 3.9 later this year - but would like to do the injection alterations first. I'm running a MegaSquirt2. Would the 3.9 injectors be too large to give a reasonable idle on the 3.5? Or any other snags?

Posted: **Fri Feb 27, 2015 9:06 pm**

One easy way to find out would be to see if the 3.5 hotwire and 3.9 hotwire injectors (Discovery V8) have the same part number.

Chris.

Posted: **Sat Feb 28, 2015 6:32 am**

I'am using the 4.2 litre Hotwire system/injectors on my Rover 3.5 with no problems at all.

I believe the Hotwire injectors on the 3.5, 3.9 & 4.2 were all the same.

Andy.

Posted: **Sun Mar 01, 2015 11:57 am**

DaveEFI wrote:I'm intending changing my SD1 EFI engine for a 3.9 later this year - but would like to do the injection alterations first. I'm running a MegaSquirt2. Would the 3.9 injectors be too large to give a reasonable idle on the 3.5? Or any other snags?

They'll all be tiny anyway, there should be no problems at all.

Posted: **Sun Mar 01, 2015 12:23 pm**

stevieturbo wrote:
DaveEFI wrote:I'm intending changing my SD1 EFI engine for a 3.9 later this year - but would like to do the injection alterations first. I'm running a MegaSquirt2. Would the 3.9 injectors be too large to give a reasonable idle on the 3.5? Or any other snags?
They'll all be tiny anyway, there should be no problems at all.

but assumed all CUX Hotwire inj's were the same capacity anyways about 185/195cc

The V8 Owners Forum -

3.9 injectors on a 3.5.

3.9 injectors on a 3.5.

Re: 3.9 injectors on a 3.5.

Re: 3.9 injectors on a 3.5.