how should this engine idle?

[marc69]

I recently bought a non running nova to be completed and used as a track car.

I eventually got the engine going but if I get it to idle at around 1000rpm, it struggles and stalls so, I have set the idle (when warm) to about 1500rpm. It doesn't stall but is a bit rough.

It is 1.4 block with a 1.6 head, kent cam and pulley and twin webbers.

I have set the ingnition timing and spent a long time trying to get the webbers to go as good as I can. I haven't tested it on the road as I haven't figured out the gears and clutch yet!

The question is, is this normal for a car with kent cam and webers or' should it give a smooth low idle?

[16v Nova Kev]

if the cam is really lairy it will sound rough at idle

[marc69]

thanks, spent more time this evening rebalancing the carbs, idling reasonably stable at 1200 rpm, I may ahve the courage to lower it to 1000rpm at the weekend when there is more time.

[novasrikev]

mine used to tick ovet at just over 800rpm on sport carbs and 280 cam

[marc69]

I tried driving the car now that I have forward gears, it wouldn't rev past 3k rpm and struggled. I looked at the plugs which were completely black so i assumed the needles in the webers must be for a bigger engine?

So, I put the good old peiberg and manifold on, got the car going, when it had heated up it still wouldn't idle below 1200, rough at this with mis/back firing although when revved the car seems better.

I have given extra tightening to the carb nuts and inlet nuts, the ignition is set pwerfectly but I can't check it as the starter has now failed.

If it is not the carb/manifold then I am stuck.......

[Steve0011]

cam needs setting up? my mate has a rally cam on his and it idles like a bag of spanners, but when hen puts his foot down all hell breaks loose :)

[marc69]

cam needs setting up? my mate has a rally cam on his and it idles like a bag of spanners, but when hen puts his foot down all hell breaks loose :)

It would be great if this is the case, if i don't give up with the car it is going to be for the track.

[marc69]

The detail as much as I know of the engine is, 1.4 sr carb block, 1.6 cavalier head with a kent (don't know which one but idling is still a struggle) cam. Twin webbers (once i can trace/afford the correct jets), F13 close gearbox(if I can get it to work!), 4-1 exhaust manifold and a magnex stainless steel exhaust.

If working and set up properly, what can I expect from this lot?

For reliability it is on the old pieberg until I get it all going.

[pyromaniac_yeti]

**** knows, but if i remember correctly then that 1.6 head is costing you power cause of the lower compression ratio. At a guess by that spec someone with a large bank account and little to no idea what they're doings built the engine. I'd guess they've fitted a 1.6 head for the bigger valves not accounting for the CR drop, fitted the lumpiest cam money can buy with no idea as to the side effects and narrow power band created, and then slapped some ebay spec webers on it to realy make it go fast.

I'd advise going to the local RR centre that specialises in classic cars - hopefully theres some kind of old bloke in there who's one of theese carb guru's who'll take one look at it, tweak a few screws and done & getting a carb rebuild kit.

If its on the pierburg and thats jetted stock, then that'll run lean and melt everything up and generally **** the engine so i'd not be doing that if i were you!!

[marc69]

Well it's now not even running!

There is no spark at the plugs, it has the cylinder type coil rather than the usual square type. I wired up a mini coil to see if I would get even a spark (assumed it wouldn't run proper on this) , not even a spark.

What else could be wrong?

[swedge]

earths are the main cause of electrical faults

[marc69]

Hello again!!

One thing I have done is gone over all the earths (even to the electric fuel pump) to ensure they are good. The coil and funny flat thing is actually attached to the gear box/flywheel assmbly so should be getting a good earth. (gearbox again).

[swedge]

is the gearbox earthed?

[marc69]

Yes, the rubbish gearbox is earthed, the lead from the earth to the starter is on and I have also put an earth from the battery earth to the body and earthed the altenator. It was going (engine, not reverse!) as well as usual and then just cut out. I first checked fuel etc but then removed a spark plug, turned the engine and the plug is not sparking.

[marc69]

Replaced the coil and flat thing beneath it and off it went, far more even than previous.

I drove it on the we bit of road in the culdesac, it actually drove although due to the short distance I didn't quite get enough distance to get into 3rd gear!

I think the cam is lairy as even with just the twin barrelled 2e2, touch the throttle and it's at 5000rpm, and in initial take off (all I could test) it is vicious for an old 1.4. Quite pleased at least the engine goes.

[Lewis.]

take the distributor off, and you will find the cam model number stamped into the end of the shaft. knowing what cam your dealing with will give you a better idea of what you can expect.

[marc69]

take the distributor off, and you will find the cam model number stamped into the end of the shaft. knowing what cam your dealing with will give you a better idea of what you can expect.

Thanks, I'll have a look in the next few days once the gale force winds have passed!

[Southie]

As mentioned, until you find out which cam you have you've no idea what timing setup you need.

If it's had a set of vernier pulleys fit then the timing is critical to match up with the cam you've got, until then the fueling will still be all over the place and that will explain the sooty spark plugs.

[Steve0011]

in initial take off (all I could test) it is vicious for an old 1.4. Quite pleased at least the engine goes.

told you 'all hell breaks loose' :) setting the cam up is a must to get the best from it. my mate used to run the twin 40's until they were banned for road rallys, he now uses the GTE multipoint setup and says he should have done it years ago :) something to think about maybe?

[marc69]

Thanks,

with the 2e2 carb, my plugs are a good colour so tat is something, until I sort everything out and discover what jets etc are needed for the webbers I'll just use the double barrel pieberg but, I was thinking of linking the two throttles so they open together instead of the vacuum system taht only opens the 2nd on at 4000rpm.

re the multipoint system..sounds good but, with my limited knowledge it sounds scarey too! I assume ecu sand everything would have to be put in and set up.

I'll have a look in the next day or two at the cam to see what it actually is.

[marc69]

take the distributor off, and you will find the cam model number stamped into the end of the shaft. knowing what cam your dealing with will give you a better idea of what you can expect.

Here is what i found after removing the distributor, i undid the two hex bolts but only the side plate bit would move.

http://i988.photobucket.com/albums/af5/69marc/Photo276.jpg


I also took a picture of the other end with the pulley but I don't know if these numbers mean anything?

http://i988.photobucket.com/albums/af5/69marc/Photo277.jpg

After looking mre at the car, I noticed that the throttle cable keeps sticking, this explained why it was revving like mad, it was ticking and then because of the vacuum, the 2nd barrel was being opened too. After some wd40 and grease, i drove it down the lane, it was almost subdued!

[marc69]

What a thicko i am, after looking at the pics, i realised there was some writing so I went and took the distributor off and here is what is written

KCN V051

anyone know anything from this?

[Steve0011]

here you go, http://www.kentcams.com/product-details/260/Camshaft/Camshaft/NVO51-Sports-Injection/

[marc69]

here you go, http://www.kentcams.com/product-details/260/Camshaft/Camshaft/NVO51-Sports-Injection/

Thanks for that. Knowing nothing about cams, is this mild or wild? It says it gives 8bhp more which although not much (if it does that) it is more than 10%.

[Southie]

Here you go Marc, found this for you ;) Download it here, page 48. CLICKYME (http://www.kentcams.com/documents/downloads/Kent%20Cams%20Brochure%202010%20Low%282%29.pdf)

http://i345.photobucket.com/albums/p379/SOUTHIE01/NVO51KentCam-NOVA-2.jpg

[Steve0011]

mild cam matey 8bhp is better than nowt eh? ;) sports injection suggests it is more suited to the mpi than the twin 40's

[marc69]

Here you go Marc, found this for you ;) Download it here, page 48. CLICKYME (http://www.kentcams.com/documents/downloads/Kent%20Cams%20Brochure%202010%20Low%282%29.pdf)

http://i345.photobucket.com/albums/p379/SOUTHIE01/NVO51KentCam-NOVA-2.jpg



Thanks

[marc69]

mild cam matey 8bhp is better than nowt eh? ;) sports injection suggests it is more suited to the mpi than the twin 40's

Thanks, mild is probably easier form me, means I shouldn't have to do any valve timing changes or anyting?

There is no mechanical fuel pump on the car so i assume this cam is purely for inj cars from what it says here. In time I'll have to decide on a mechanical pump (and find a 1.4 SR cam) or stick with what I've got. This will be sometime when it is actually on the road and I've driven it for a bit.

[Lewis.]

as said, it's a fairly mild cam, so should idle okay. it has a vernier though, so the valve timing will probably still need setting up.

If you want a mechanical pump, then I have a 1.4SR cam, cam box and fuel pump here. PM me if you're interested :thumb:

[marc69]

as said, it's a fairly mild cam, so should idle okay. it has a vernier though, so the valve timing will probably still need setting up.

If you want a mechanical pump, then I have a 1.4SR cam, cam box and fuel pump here. PM me if you're interested :thumb:

Thanks, i have never set up valve timing ( may give me a better idle?), do I just make sure that the marks on the crank meet when thye notch in the cam are at the top?

[Steve0011]

Thanks, i have never set up valve timing ( may give me a better idle?), do I just make sure that the marks on the crank meet when thye notch in the cam are at the top?

its a little more invloved than that :( i have a mildish cam on mine, you need to download the spec sheet for the cam. my mate helped me wth mine he had a fancy meter with a probe down the spark plug hole. it took about 2 hours to get it spot on :(