antwan
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| posted on 3/12/09 at 08:38 PM |
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This must be an easy one for pinto lovers
Just finished cam work on my 2.0 pinto - new burton 32.33 cam (fast road), springs, followers, balls, bearings, stem seals and a vernier pulley. The
car before the upgrade was.. and lets be fair.. a pudding. Car is alot quicker now and should be set up correctly finding tdc, correct cam timing,
ignition blar blar..
My question is; is there any fine tuning which can be done to maybe lessen torque, increase top end power? I am still not convinced it is running at
optimum. What tweeks to cam/ignition timing etc have what effects. It seems the engine has less power at high revs, not more!
Dont get me wrong the risk of spinning the wheels in the wet in 3rd is an issue but can I 'tune' the power
Am I being an ass, this is a pinto when all said and done!
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Steve G
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| posted on 3/12/09 at 08:47 PM |
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You'll no doubt find it needs rejetting to get the top end power. When its at the rolling road they can adjust the cam timing to vary the
characteristics of power and torque. Have you fitted a vernier cam pulley at all??
Isnt the best static timing figure given by Burton Power to suit that cam??
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RAYLEE29
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| posted on 3/12/09 at 08:54 PM |
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Hi, try a little more advance on the cam for more top end and a little on the ign too dont go mad or youll end up with detonation and melted pistons
Ray
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antwan
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| posted on 3/12/09 at 08:55 PM |
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Yep fitted a vernier pulley as it worked out that I was about half way between belt teeth for full valve opening. What do you mean by static timing.
is this what i have done? using a timing disc, dti guage etc?
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mookaloid
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| posted on 3/12/09 at 08:57 PM |
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For more top end power you need to improve the breathing. This means opening up the ports, gas flowing, modding the valves, bigger carbs etc. etc.
Don't give up - you can get some very satisfying power from the the Pinto
"That thing you're thinking - it wont be that."
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antwan
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| posted on 3/12/09 at 08:58 PM |
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Is that the general rule? more cam advance = more top end power? Worth a go tho. Its also being VERY reluctant to start recently. should this be an
indication (of impending doom etc), although I did find the carb mixture was out due to new cam.
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antwan
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| posted on 3/12/09 at 09:01 PM |
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wrt the gas flowing of the head, although the internals have a roughness to them, there is no big casting faults etc which i was expecting to see
although there is a big difference between the inlet manifold and the port of the cylinder head, quite a stepped change. What does gas flowing do and
what sort of money would i be expected to pay?
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mcerd1
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| posted on 3/12/09 at 09:38 PM |
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once everything else is pretty much sorted I think you can move the peak torque/power around a bit buy playing with the length of the exhaust primary
pipes and inlet manifold, but thats not the easiest thing to change and it soulds like you've got more to do before you get to that stage...
you might not think that the standard ports look too bad, but they are too big and the wrong shape 
there are a few good tunning books for pinto's, look for the des hammill and david vizard ones - both give details of the porting etc.... well
worth a read
linky
[Edited on 3/12/09 by mcerd1]
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snapper
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| posted on 3/12/09 at 10:07 PM |
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You are chasing BHP for the wrong reasons..........
BHP at any costs makes a car slower unless you are at BHP peak revs all the time......
However, torque is all in racing and is much more relevent to (mainly) road driving.
Talk to race teams (and i do) and they will talk torque and how much they have over how much of the power band more than peak bhp.
A quote for you...
BHP sells engines,
Torque wins races.
Drive your car, or any car and log where the car spends most of its time...
I was suprised when i looked at my Megajolt log (road) and found whilst i was in the zone with full on adrenaline 5 to 7K revs, most of the time the
car was no more than 4k.
Get the grunt low, you will be quicker IMHO
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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snapper
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| posted on 3/12/09 at 10:14 PM |
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Have a look at the Turbosports forum, very very good Pinto info.
To much cam and no compression = no good.
To much compression and not enough cam = detonation (Knock)
Vizard says less duration more lift (under 300 degs about 12mm lift)
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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mark chandler
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| posted on 3/12/09 at 10:24 PM |
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To centre the cam when the piston is at TDC if you devide the inlet and exhaust lobes then they will both be pointing up the same amount.
Compared to the above improve bottom and mid range by up to 10% advance the cam 5 - 7 degrees, this is the prefered setting by most people as you
drive low and mid end, but you lose 5% top end.
Cam retarded 5 degrees from central lose 5%-10% bottom, gain 5% top end.
For myself many years ago I had a pinto with 285 cam, skimmed heads and large valves, made 140bhp with standard carb running 7 degrees advanced.
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steve m
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| posted on 4/12/09 at 09:11 AM |
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So to reverese this thread slightly what is the best way to get better torque ?
regards
steve
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mcerd1
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| posted on 4/12/09 at 09:20 AM |
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quote:
Originally posted by steve m
So to reverese this thread slightly what is the best way to get better torque ?
regards
steve
a bigger engine 
I've got 93mm pistons in my pinto, making it a 2090cc
<<< in fact thats one of mine in my avitar at the moment 
[Edited on 4/12/09 by mcerd1]
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steve m
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| posted on 4/12/09 at 10:23 AM |
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somwhere in the big scheme of things we are being cheated ??
i can spend thousands in making my engine more powerfull and more BHP
but i have to buy a bigger engine if i want more torque
i wos done !!
steve
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mcerd1
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| posted on 4/12/09 at 01:30 PM |
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quote:
Originally posted by steve m
but i have to buy a bigger engine if i want more torque
i wos done !!
of course you can play with different cams (there are high torque ones out there), timing, exhausts....
and then there are turbo's and superchargers 
but at the end of the day the size of the pistons * the length of the stroke will have a big influence
think about it like this: boring out a pinto to 2.1 won't give you much (if any) power increase, but should make a noticeble differnce to its
torque (at least it better after all I've spent on mine )
in the real world how it feels to drive and how quick is more to do with where the torque and power are in the rev range
its possible to have a 200bhp pinto that revs to say 8000rpm or more, but ticks over at >2500rpm and has no real grunt till 5000 - but that
wouldn't be much use/fun on the road
power and torque are related by engine speed - so if your engine has power and rev's, but doesn't produce much torque, then you have to
change gear more (think RX8 vs V8)
quote:
The power transmitted by a rotating shaft = the torque T x the angular velocity
but then you get into the weight of the car, type of driving, gearing............ and so on (we could be here all next year)
so sticking to what makes a se7en with a pinto go faster ("By far the best proof is experience" and the pinto's biggest problem by
most acounts is the port size/shape. so the right head work and the right cam for your driving won't be money wasted
then I guess probably carbs/TB's, exhaust and ignition
once your happy with all that you could bore it out
but if budget is really a big problem then I hate to say it but a stock 16v engine is probably the answer
[does that all make sence ? / have I got anything wrong ? ]
[Edited on 4/12/09 by mcerd1]
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