gticlassique

hello , i have a problem with my engine cvh1600 .

the specs are :

- cvh1600 xr3i stock bottom end
- hemi head , ported
- rs1600i valves
- rs1600i springs
- newmancams mechanical followers
- rs1600i camshaf
- rs1600i exhaust manifold
- twin weber 40 , 36 choke , correctly jetted

the engin can't run under 6000 rpm and i don't know why ?

at the past i changed ignition , fuel pump , cam belts , plugs , etc etc all had change 3 times , but the engine continue to cut at 6000 rpm

help me , i don't know what is my problem

on this video you can listen the engine cut at 6000 rpm

XR2

What type of ignition do you use?

XR3i distributor?
RS1600i ECU with twin ignition barrels?
EDIS standalone system?
Aftermarket ignition system?

gticlassique

i use xr3i distributor bosch .

i tryed : xr2 lucas distributor , escort lucas distributor and another bosch xr3i distributor .

no differences between these .

i tryed another plugs ( denso , qc57c , motorcraft .. )
another ignition leads
another ignition coil
and electrical connections

no differences

XR2

You're aware all of them came with a built-in rev limiter?

Standard rev limit is set at about 6500 rpm.

gticlassique

yes i know , but the engine can't run over 6000 rpm .

i'm sorry , the firt message is wrong , the engine can't run over 6000 rpm , not under 6000 rpm .

XR2

... because of the standard rev limiter!

When you're using a Bosch type XR3i distributor, use a rotor arm without a rev limiter, problem solved.

gticlassique

i use a rotor arm without rev limiter , with the same distributor on another engine , he run over 6500 rpm .

Canada1

If it is not ignition related issue I would guess at valve spring float.
Weak valve springs can certainly be a rev limiter.
Were the rs1600i springs new? What was the installed valve spring height?

rebuilt heads typically sink the valves which requires shimming to bring the valve spring closed height (installed height) to the correct spec.

Cheers