Restoring Power

[m4dmike 0]

Right i had just finished rebuilding an engine to put into my rally car after a cracked block. i have noticed the power has drops off bigtime after about 4500.further investigation on my part revealed a quite badly worn camshaft. im wondering is there many other things thatwould be contributing to this problem or will a replacement cam sort out that issue, if its even the cause of the same issue.

 

the engine itslef is totally standard. with the original oil pipes and the like. would a cracked hose or dicky sensor be to blame and is there anyway i can test for them things.

also i got the new engine from a citroen no idea what it was though. it did have a mi16 type inlet manifold on and i was hoping the camshaft might be the same. cos its in great shape and its already there.

 

any help would be greatly appreciated. as this is the stuff you get with experience. like retireing on the 4th stage of your first rally because of the one wire you didnt think needed reinforcing

[welshpug 1,657]

sounds like youve got a 1.9 engine as a replacement...

 

might as well stick an aftermarket cam in there if its all apart

[205_sunderland 4]

sounds like the bxgti 8v engine, it has flat top pistons for higher comp, same block etc as the 19 gti and has an ally mi style manifold and slightly different head (plugs are not in recess hole like normal xu as head is machined out at front for them) . I had one in my 19 gti few years back as they runn of same management etc so its a straight swap. I think they only come in 1.9 form and are used alot for hill climb due to high comp ratio

Edited September 15, 2011 by 205_sunderland

[m4dmike 0]

sounds like the bxgti 8v engine, it has flat top pistons for higher comp, same block etc as the 19 gti and has an ally mi style manifold and slightly different head (plugs are not in recess hole like normal xu as head is machined out at front for them) . I had one in my 19 gti few years back as they runn of same management etc so its a straight swap. I think they only come in 1.9 form and are used alot for hill climb due to high comp ratio

 

 

 

ok cool. Thats great news. The cam i got with it was in great shape too and can use the buckets and shIms too.

[welshpug 1,657]

I doubt you'll be able to use the shims, or at least every one! might be lucky with the selection from both engines that you'll get fairly close though.

[205_sunderland 4]

i would do a bit digging first to make sure the cam is identical as im pretty sure it is but it was over 2 years ago since i had mine, i know the full gti head set fitted (valve steams etc) bar the inlet gaskets (ports are different) as i rebuilt my head when i did the head gasket.

 

ANYONE ON HERE KNOW FOR SURE? or i suppose you could just remove the cam and compare the two as i imagine youd be able to tell easy if there identical with a few measurements

[DamirGTI 342]

ANYONE ON HERE KNOW FOR SURE?

 

I might ... just need a picture of the camshaft (paint ring marks) ..

 

Damir

[kyepan 291]

if you have a DTI you can plot the curve of the cam with it still in place, and then have some idea of what it's duration and lift is.

 

J

[m4dmike 0]

Ill get on the photo so. Would all this explain why the power drops off so dramatically. Considering that its running with a pug gti head from a1.6 with a fairly worn cam

[DamirGTI 342]

If the camshaft lobes are worn out it'll certainly affect the performance ... and when the lobes go bust they usually take the lifters too so check the lifters if they're not dished on the top ...

 

Dunno by which state of drama the power goes off , but id check the valve clearances , timing belt alignment , ignition (could be duff ignition module ... or retarded advance ..)

 

Which engine is it on the end ?! 1.9 bottom end (there where a few different 1.9 bottom ends with deep dished DKZ , mild dished D6B , low dished DFZ and flat top piston crowns DDZ ...) with early 1.6 head/camshaft ?

 

Damir

[m4dmike 0]

Ill get on the photo so. Would all this explain why the power drops off so dramatically. Considering that its running with a pug gti head from a1.6 with a fairly worn cam

[m4dmike 0]

EI don't really know how to identify the engines or parts because its a complete mis match of bits. Just want to make it work consistently. And cheap. Im wondering would a leaky pipe from the filler pot cause a power loss too or maybe a dodgy sensor.