RV8 EFi Manifolds

[B@man]

Hi all,

Just mulling over some (future) upgrades for my 400SE, Does anyone know if the early SD1 EFi (Flapper) manifold will accept the later (Hotwire) fuel rail and injectors, currently the injectors are working but if I decide to upgrade the injection & ignition I'm considering updating the injectors for a more modern design with a bit more choice.

Will they fit or is it later manifold job ?

Thanks

Edited by B@man on Sunday 22 March 20:40

[K4000JB]

B@man said:

Will they fit or is it later manifold job ?

unfortunately you will need to change the manifold

[Boosted LS1]

I think it can be done but it's not straightforward. Reason I think this is because I'm sure a friend with a tasty MG did a conversion. It was Nick Smallwood if that helps. I just can't remember how he did it though.

ETA, there may be some info here:

http://www.mgcars.org.uk/v8_conversions/links.html

Edited by Boosted LS1 on Sunday 22 March 22:34

[grahamw48]

B@man said:

Hi all,

Just mulling over some (future) upgrades for my 400SE, Does anyone know if the early SD1 EFi (Flapper) manifold will accept the later (Hotwire) fuel rail and injectors, currently the injectors are working but if I decide to upgrade the injection & ignition I'm considering updating the injectors for a more modern design with a bit more choice.

Will they fit or is it later manifold job ?

Thanks

Edited by B@man on Sunday 22 March 20:40

When I was down at Richard Thorpe's (RT racing) last summer he was musing about the differences (?) between the later hotwire fuel rails as fitted to the 95' pre-serp Chim HC motor fitted in my 400SE, and earlier ones.
Now I may be having my usual senile flashbacks here, but possibly there IS a difference.

Might be worth checking out.

[Boosted LS1]

Early rails have a short hose between the injector and rail, hotwire has the rail mounted onto the injector.

[B@man]

Thanks people you have confirmed my suspicions, the later Hotwire type manifold will accept "standard" type fuel injectors rather than the weird jag / rover ones.

Considering binning the dizzy and clockwork injection and going for VEMS with wideband O2... only had the car 3 months !

Quinny could be interested in that manifold (my RV8 parts stash is growing already) PM me please !!!!!!

Edited by B@man on Monday 23 March 09:46

[rev-erend]

I think the injector types are different .. one being low impediance and the other not .. so a direct swap in not possible without a bit of additional wiring trickery.

But before all that - I think you should question why ..

Are you after more power .. if so then a complete injector / ecu swap to hotwire and 14CUX is not going to reap huge amounts of bhp .. if any and you will also look the superb pops and bangs the wedge is famous for.

There is torque gains to be had by changing to fully mapped ignition and a bit more power by having the inlets enlarged and trumpets fitted.. along with a bigger throttle (72mm).

[B@man]

Yep - thats the plan - VEMS, Wasted spark, 72mm throttle body to go with me ACT carbon trumpets, just thought I'd look at the options for updating the injectors while I'm at it....

Yes will lose the pops' & bangs but I would think they can be mapped back in but using a fuel cut on over-run to achieve the same lean mixture ?

Edited by B@man on Monday 23 March 10:31

[rev-erend]

Or you could go the whole hog and get some decend inlet manifolds like mine

[spend]

There are a few different hotwire manifolds, mainly affecting plumbing take offs and sensor locations. Early and late are completely different shaped castings in the area between pot 2 & the stat housing IYSWIM. Some have only the forward part of the waterway 'box' underneath tapped, early ones have the back tapped also (for heater pipes).

[B@man]

rev-erend said:

Or you could go the whole hog and get some decend inlet manifolds like mine

Nice, I've seen those somewhere else like the blue LED bling !
Would need at least a 5 litre to go with them

At least a programmable ECU opens the door to future fiddling...

[rev-erend]

Yes - the leds were just added to make the photo more interesting.. and to show the straight run to the back of the valves..

[B@man]

Doh - And I thought the LED's where a permanent install to go with a plexi glass bonnet

Thanks to all for the advice, as I said just kicking ideas about at the moment.. honest - the RV8 bits I bought off ebay are just spares

[grahamw48]

Hmmm, I hesitate to post a pic of my grotty motor after the rev's object of beauty ....but, here is my fuel rail/injectors for comparison with yours.

I would really think about losing or changing that lovely overrun music though. My 390 was a flapper, and to be honest... just as quick as this one, but heavier on fuel.

[B@man]

Why is everyone's engine tidier than mine

[grahamw48]

Please tell me you're joking.

[B@man]

I wish I was

Hey I've only had the car three months, it will get better, honest.

[pwd95]

My Hotwire 400 SE with big valve heads & Mark Adams chip felt positively sluggish next to my Flapper 450i J.E. jobbie. If I had another Wedge I'd be installing a 4.6 & a Webber 500.
There's no substitute for simple capacity. Much more power & a lot less fiddle & hasstle.
All IMHO of course.