9 replies to this topic

[Petro1head]

I have now run in my 1330 A+ engine

Spec is:

Russes engineering re013 cam. Similar to kent 286
Swift tune head with 37mm inlets 29 exhaust
Maniflow LCD to rc40 twin box
Twin hs4 with AAB needles with k&n cone filters
Std rockers
Calver modded distributor max advance 28 deg

Since running it in, about 500 miles, then engine in strong throughout the mid range but when it hits 5500 rpm it's like a rev limiter cuts in.

I checked the timing and am getting 28deg NTSC at 4500 rpm

Switch the engine off and removed a plug which looks like its running a tad lean

edit:  DSCF6688.JPG   50.41K   5 downloads Looking at this photo blown up I we deffo say thats a bit week!

If its running lean would I get this symptom?

Calver originally suggested AAM needles but they are weeker at the top end according to Minty's site so what needles should I try next and is there anything else I should check?

Edited by Petro1head, 25 April 2013 - 05:54 PM.

[johnnyblaze]

what fuel system do you have?

[Petro1head]

Single tank with SU pump

[johnnyblaze]

su pump, manual or electric? wander if your running out of fuel at high revs

[BritishRacingGreen]

Have you had it on the rollers after it was running in? You shouldn't really be taking it to the top end until you have. I'd make that a priority, get the fueling and ignition perfect, especially on such a high performance engine.

[Earwax]

I would be checking the fuel in , as suggested above, but also check the overflow/return from float bowl is not blocked .. can create some back pressure affecting the float bowl- run it disconnected to diagnose if unsure you have cleared it, but not recommended for long term - sometimes 'bleeding' from the top of each float bowl can get rid of air pockets -NOTE best way is engine off fuel pump ticking (electric) but if mechanical ONLY when engine/exhaust is COLD - as this involves spilling petrol in engine bay - if any doubt dont do it

[Petro1head]

su pump, manual or electric? wander if your running out of fuel at high revs

Electric, possible cause tho

Have you had it on the rollers after it was running in? You shouldn't really be taking it to the top end until you have. I'd make that a priority, get the fueling and ignition perfect, especially on such a high performance engine.

Indeed not been on Dyno yet

[Petro1head]

I would be checking the fuel in , as suggested above, but also check the overflow/return from float bowl is not blocked .. can create some back pressure affecting the float bowl- run it disconnected to diagnose if unsure you have cleared it, but not recommended for long term - sometimes 'bleeding' from the top of each float bowl can get rid of air pockets -NOTE best way is engine off fuel pump ticking (electric) but if mechanical ONLY when engine/exhaust is COLD - as this involves spilling petrol in engine bay - if any doubt dont do it

Oveflow/return. No return and cant see any leaks when pump on but engine off, if you get my drift

[Earwax]

Check the tank isn't holding its vacuum - acting against the fuel pump - take fuel cap off and see if air rushes in or out -- probably not but easy to check.... that needle and timing (if correct) are thereabouts (actually pretty well specd) certainly not way out - check that the distributor is advancing to its stop sounds like fuel pump not keeping up or one of the float bowls emptying

[Guess-Works.com]

Until an engine has been setup correctly you should not be running high rpm anyway... for fear of detonation or over fuelling and causing bore wash...

IMO, get it set up correctly then look for problems.