Power Dropping Off At 4000 Rpm

[jonnygoodhand 0]

Hi

 

I've recently had a TU3S engine (this one) fitted to my Rallye and have had a new set of DCOEs fitted.

 

I then took it along to Aldon to have the carbs fitted and set up and they have just called to say the engine is well down on power (75bhp) as it drops off just after 4000rpm and is unwilling to rev.

 

Apparently the compression is very high.

 

Does anyone have any ideas as to why this could be? I'm not very technical minded, and as for the specs of the engine, I know only what is in the above ebay listing.

 

Thanks, John.

[bren_1.3 1]

the advert says it had a skim on the cylinder head. so probably a heavy skim if compression is that high.

 

if this aldon place is setting the car up, then id imagine they would have told you it could be cam timing, ignition timing, or the carb setup. this place that is setting up your engine should be dealing with all this. could be anything though.

 

you really need to do your homework before you sart buying supposed race engines, and fitting carburettors. especiallly not being technically minded as you'll soon find it going to cost you a fortune to set the thing up right. ive just noticed its running a dizzy so more setup time fine tuning the dizzy to suit the cam and compression.

 

i really dont mean to have a go but youve already been f*cked over with the price of a pair of webers and manifold and the thing is STILL 10hp DOWN on a standard TU3S !

Edited April 26, 2007 by brens_1.9_wide_arch

[Rippthrough 98]

I'd guess at cam timing.

[johnnyboy666 195 1 Cars]

hmm so it was u who outbid me on that one then eh?? lol

[jonnygoodhand 0]

hmm so it was u who outbid me on that one then eh?? lol

 

Looks like you may have had a lucky escape!

[stu_woac 1]

replace the coil sounds like weak spark your garage should know what they are doing to be honest and shouldnt need your help so a bit conserned, the engine is no where near race spec I'm affaired (standard dizzy is a big clue aslo vavle springs look unchanged and ports look to small mine are alot larger than the standard gaskets where they look smaller ) but still should be seeing around the 100bhp mark easy cam timing could be out to but thats not hard to set up so your garage would know that, aslo we are taking flywheel figure right??

 

p.s. this is the engine you bought looks like its running sandard alround to me

 

Edited April 26, 2007 by stu_woac

[Jrod 7]

I might just paint an XS engine and sell it for £350.

 

Have you checked it actually has a Cam and isn't standard?

[jonnygoodhand 0]

I might just paint an XS engine and sell it for £350.

 

Have you checked it actually has a Cam and isn't standard?

 

I did have a look at it, and it did appear as he stated. But, I'm far from an expert.

 

Plus, he seemd like a decent chap! So I took him on his word.

 

Niave, I know, but hopefully I'll find out for sure tomorrow when I go and see the guys at the garage...

[djinuk 2]

is there a chance you have a air leak in your intake manifold, try spraying some easy start around the gaskets when the engine is running, if the revs build up for a couple of seconds then a air leak is the problem

[jonnygoodhand 0]

This is a print out from Aldon; the garage who have set-up the carbs for me. The timing seems fine and I'm happy with the work they've done for me.

 

 

Their thinking is that the wrong head is on the engine! Also, they doubt the cam is a piper 285, which is what the guy who sold me the engine claimed.

 

Lesson learned...

[Jrod 7]

I always thought that seller was a knob, took over 2 months to post a strut brace to my mate.

[stu_woac 1]

the head isnt the wrong one but could of been ported badly by himself so your air velocity is srewed, your garage could of found out what the cam was for you very easy did they not try?