Well, despite my concerns over my electronics skills. I've assembled the megajolt and hooked it all up on the bench. Everything that could be tested on the bench seemed to work ok. I was amazed and incredibly proud of myself. Now I've just got to sort out the trigger wheel and to work out how to connect the TPS to the downdraft. I want to make sure the MJLJ is functioning well before switching over to the bike carbs. Then its just enjoy some summer driving before moving on to the next project.

CheersJohn

Well, it's been a frustating time for me. I desperately wanted to do something with the S4 to kind of make it mine but all my plans went awry. The R1 carbs that I bought off ebay never arrived and I had a hard job getting my money back. Pressure of work and re-decorating has made it difficult to find time for anything other than the odd ten minute blast down the road.

Have finally got the suspension sorted in a way that is right for me. I, unfortunately, had to raise the ride height by about 30mm as I was grounding the sump getting in and out of the garage. Once I've got to work with the concrete and levelled the entrance to the garage out, I'll drop it down again. I softened the dampers a bit as it had been like a go-kart and softening the front a couple of clicks more than the rear seems to have cured the embarrasing habit it had of drifting round bends.

I've now got a set of fireblade carbs and a manifold from GBS which I hope to fit this weekend. Has anyone fitted bike carbs? Is it necessary to connect the choke or can it be left off like webers?

Once the carbs are in place and tuned as well as I can, I'll install the megajolt. I've got everything in place except the trigger wheel. Trying to find an engineering shop that can machine the pulley for me.

So, all of that means that to date I've fitted a pair of cheap supermarket seat covers and cobbled together a pair of wind delectors to stop the missus moaning about her hair and about being deaf in her left ear. Sometimes I wish I was deaf in both of mine.

Cheers John

:D Nice picture that Jon.

Without looking at his last post on his Legerra build I cant remember if Jonno went Carbs or throttle bodies but as for starting and the needs of chokes I would tend to say yes on carbs without accelerator pumps if lots of cranking is to be avoided.

If you are grounding the sump - have a check on the engine mounts - they could be getting past their best and new ones might give a bit of a lift.

I 'm not sure if you mean the car is oversteering or understeering - what tyre pressures are you using?

Seat covers and wind deflectors look good from the photo.

Cheers

Andrew

I went down the throttle boddies and megasquirt route as i found a setup already made up and working :).

I have got zx9 carbs, megajolt & inlet plate (but not got a manifold made up !)

Good luck and have a look on locostbuilders and westfield fourms as theres quite a few people using bike carbs on a pinto with good results.
(i think mains are drilled out to about 1.7mm).

Oh nice pic and glad your enjoying driving about still :D

Hi guys,

Thanks for the info and the comments about the picture.

Andy,

It was oversteering really badly. An example, just outside our village, which is in the background in the picture, is a long sweeping right hand bend. I would normally take it easily at about 70ish in my Galaxy. At about 60 in the S4 the rear end was right out. luckily, the steering is very responsive and I was able to keep it under control and just about on the right side of the road (remember I'm in France) as a friend with an Elise appeared at speed in the other direction. I took it for a run on a road with plenty of forward vision and it had a real tendency to step out particularly on right handers possibly because we drive on the wrong side here so a right hander on the right side of the road is obviously a tighter bend. However, as I say by making the rear dampers a bit stiffer than the front it holds the road much better now.

I think I'm running about 25psi. I judged it by eye. Just pumped it up till the sidwalls weren't bulging.

Thanks for the tip on the engine mounts. I'll check them out. But I have got a bit of a step into my gagage, I need to make it more of a gradient.

Now I need to find myself a choke cable.

Cheers
John

Jon,

Forget the shape of the tyres :o - you should not have any more than 18-20 psi in the tyres 25PSI :o :o small wonder you have no grip - My westy runs 17PSI max at 20 its all over the road.

Also softening the rear should be better than the front for solving oversteer - I seem to recall that I had the the back end on no more than three clicks and the front on about 5.

It could really do with some 150lb springs at the back rather than the 175's to soften it up a bit more

BUT LET THE TYRES DOWN :D :D

Cheers

Andrew

So ignorance is not bliss after all!

I must seem like a proper clutz at times. This is all new to me. The physics in my head told me that stiffening the rear would transfer some of theight to the back and give more grip. Whatever, it seems better now, I haven't had a sideways moment for a while even though my confidence is growing and I'm driving a bit more agressively now but I'll, play around with it a bit and see what happens.

And I will let a bit of air out of those tyres.

Thanks again
John

Have fitted the bike carbs now (will try and get some pics on tomorrow) and it starts and runs. Had a bit of a disaster when cutting a bit of fibreglass away to fit the airfilter box. The angle grinder gripped, shot forward and sliced through the wiring of the lumenition box (just as well I'm planning to replace it). Rejoined all the wires and the spark, at least seems fine. However, I'm now getting lots of backfiring and the exhaust gets extremely hot. I think it must be burning fuel in the exhaust pipe and the can and therefore running way too rich. Does that sound likely? If so what is likely to be the best solution? Is it possible to lean the mixture just by adjustment or should I be replacing the jets. Any advice very welcome. On the plus side, at high revs it pulls like a train and sounds awesome.#

John

Hi John
Have you drilled out the main jets, should be 1.7mm on a 2 litre .
I would say it was running lean if it is overheating. what bike carbs are they?
Some bike carbs need the airholes blocked off to enrichen mixture at higher revs.


Graham

Hi Graham,

They are Fireblade CBR 900 carbs bought with the manifold from GBS they claim to have rejetted them but I don't know what to. I assume 1.7 as that seems to be what everyone advises. I did tell them it was for a 2L pinto. They said it should be just a straight bolt on job.

I am running it with the pinto mechanical pump and a regulator set to 2.5. I will fit an electric pump, probably a pacet but I havent got one yet and also need a blanking plate for the mechanical pump.

I should have said there is a lot of hesitation at low revs but, like I said from about 4k it goes like a rocket.

Cheers
John

I would agree that it sound like its lean - a lean mixture takes longer to burn so its still burning when the exhaust opens - hence the heat - It may also be that there is not enough advance on the ignition I would add 5 degrees and see what effect it has especially if you have lost vacuum advance down the bottom end. Might make it a bit awkward to start though until you get the MJ working

Be interested to know what happens when you stuff a hotter cam in it :D

I think another Youtube vid of the installation and the sound is in order John

Andrew

Sounds like its been jetted correctly as its revving higher up the scale (above 5000rpm)
Try opening the airscrews out,(up to) 2.5 turns . needles can be set (out or in) by tiny circlips.
Its all going to be bit off guess work .unless you have a wideband sensor or somewhere you can take it to get it tuned up correctly.

Agree with Andrew get some vids and pics up


Graham

Thanks for the advice guys. I think I agree with you now. My stupidity again in thinking it was rich. Proof of the pudding I think is that when I'd been for a run this afternoon taking a video (will get it up on youtube this evening if I can) and it was really hot, I pulled the choke on full and it seemed to run better I have taken a couple of pics below:

Note the waterpipe is a temporary arrangement. I will do a nice bit of copper when I get the time.








John

:D

Just watched your vid John it certainly seems to rev cleanly enough now

May be worth moving all this work to the Pheaton S4 part of the board to keep it the right place as its a bit more than an update now - and It will be nice to follow up on.

Will see what I can move.

Andrew

Well that was nice and easy. Hope you agree that its worth moving.

Did you notice any improvement when playing with the tyre pressures? and have you had a play with softening up the dampers at all?

From what you say about the choke etc it sounds like the timing could do with a good dose of advance - also worth finding out what max advance you have which should be all there by 3500 rpm

That rev counter sure seems busy in the vid but to be honest with the stock cam all the power will be gone after 5500 and would be better to use the torque from 4000 - even if your way sounds better :D

Still got this piece of bonnet to fill that hole you have now.

Just seen on e-bay that the yellow s4 has turned up with a bit of a discount

Cheers

Andrew

I have to start this post by saying I'm new to all of this. Haven't picked up a spanner in anger to a car for a long long time. Also, despite my inexperience, I'm getting on a bit so dementia is not out of the question!

My other car is in the garage at the moment so I used the Dutton this morning to go to a job. Lifted off as one should while passing a road gang. There was a backfire like a bomb going off. Frightened the wotsit out of them. When I got to the job, I lifted the front a did the usual standing there scratching my head. A thought occured. When I fitted the manifold which is much thinner than the cast one it replaced, some of the studs were too long and I packed them with washers. So, I undid them again and stuck another washer on. What a difference! It was obviously sucking air in through the joint. I thought I had tightened them really well but I had just run out of thread.

There is still a little backfire but now its of the sort that from what I read on other forums some people actually quite like but I'd still like to get it right. I've given it a few degrees more advance and the its improved a bit and the idle picked up. I'll try a few more when I get the chance.

I have softened the tyres Andy and I think it is an improvement haven't yet softened the dampers but will give it a try.

I'm not sure about the bonnet. The Filter is touching it. I'm thinking about putting a scoop on it. What do you think.

Thanks again for all the advice

I have a timing light somewhere, I'll dig it out and see what it's saying. The youtube vid is still the old one havent had time to get a new one up. Will asap.

My mistake, the video is on youtube. It told me that it hadn't uploaded

s4

John

There is a trend developing here :P :P

I will try and find an on-line Altzhemers test for you :lol: ;) ;)


Oh and as for the scoop - less is more everytime. - If there is not a Vacuum connection on the dizzy the popping and banging on overun is to be expected as the mixture will go very lean with results as explained before re burn time.

Andrew

You appear to get a camel/yak caught under the vehicle at about 2 minutes 22 seconds along with a song bird at about 6 minutes :D

Your not ace ventura are you? :lol:

G

The camel yak and songbird were obviously the sound of air getting sucked in through the small gap between the manifold and the head. The extra washer has eliminated it.

There is a vacuum on the dizzy its the black tube that can be seen in the pics connected to the manifold tube to no4 cylinder.

I agree about the scoop. I'd rather keep the liines clean but am concered about air restriction as the filter is actually in contact with the bonnet. I'll do another pic for you to see (when I can remember where I left my camera) ;) . Maybe its not enough to make a real difference.

John

As promised, Pic of the filter contacting the bonnet



John

Still wondering about this bonnet cut-out. What do people think if I made a new backplate with the holes offset by 20mm or so to lower the height of the filter so that I could fit the bonnet. It would mean that the airhorns would not be central in the filter cavity. Would that really affect airflow badly?

Just bought tickets for Le Mans Classic and would like to have it looking good for then.

John

Ps. Have posted another vid of a drive after the manifold leak was sorted:
video

Now I'm scared. I now have a Kent FR31 kit and a quaiffe adjustable pulley en route from Rally Design and I have never tackled anything like this before. I'm already having nightmares about never getting the engine running again. If anyone knows of a good step by step cam replacement resource on the web, please let me know.

John :(

:D

There should be plenty of advice in the cam kit and if not the Kent site - the technical page is about cam fitting - and or their technical help line would be the first stop.

You certainly seem to have a continuing thirst for power John B)

On the air filter /Carb front - thats a tough one if the filter is blocked by the bonnet its offering no benefit at all if it can be moved so that more filter area is able to see air then it would be better unless in doing that the filter internally gets too close to the bellmouths.

May be a case of opening up the hole in the bonnet being the best bet.

Cheers

Andrew

Thanks Andrew,

Unfortunately, although I'd rather not, I do think opening the bonnet is the only option as adjusting the backplate is going to bring the bellmouths too close to the filter.

Re: thirst for power, I know that I'd find it much easier to achieve a good P2W ratio if I started with a lighter chassis but I do love the Dutton. I really just want to be able to show a clean pair of heels to my mates' Elise. I can see that in the not too distant future, having spent a small fortune and lots of time on the pinto, I'll pull it out and stick a V8 in.

Actually came close to buying a vitesse on ebay france the other day but the wife happened to look over my shoulder before I got the chance to hit the buy it now button :angry:

Finally got around to taking the head off. Everything is looking good. Nice porting work Andrew! I've fitted the new valve springs and inserted the fr31. Those little clip retainers are a pain in the wotsit. I got the knack of it by the time I got to the last one.

While I've got the rad and things out, I'm going to take the opportunity to fit the trigger wheel for the megajolt and a bracket for the VR sensor. Then I'll cobble it back together and try firing her up.

Cheers
John