alfas
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| posted on 7/9/15 at 10:20 PM |
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if its a sierra diff they end with 3.9 ratio
so still not enough for your demands...means changing wheels.
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bumpy
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| posted on 7/9/15 at 10:22 PM |
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quote:
Originally posted by alfas
ok, than diff needs to be changed to something around 4.4 to 4.6
dont know the nearest availble ratio for your specific diff.
is it a sierra diff?
It is indeed.
A 4.4 diff would take the revs at 70mph to about 3100 rpm. Is that about right?
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bumpy
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| posted on 7/9/15 at 10:23 PM |
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quote:
Originally posted by alfas
if its a sierra diff they end with 3.9 ratio
so still not enough for your demands...means changing wheels.
Yes, I thought I remembered that figure 
[Edited on 7/9/15 by bumpy]
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alfas
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| posted on 7/9/15 at 10:25 PM |
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3300 would be moire than right with 70mph...and you would gain a massive amount of acceleration...believe me
but as ford´s original diff ratios end with 3,92 i do not know what i can recommend you. are there aftermarket diff-ratios like 4.1 or 4.4 available
meanwhile?
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bumpy
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| posted on 7/9/15 at 10:27 PM |
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quote:
Originally posted by alfas
the cheapest tuning is a lower diff ratio and/or smaller wheels..Low gears give fast acceleration, high gears give better cruising and higher max.
speed
[Edited on 7/9/15 by alfas]
Now this is where I have a MAJOR mental block. My 'logic' tells me if a car is over geared then changing down a gear or two will
eventually get to a situation where that becomes irrelevant.
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Adamirish
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| posted on 7/9/15 at 10:43 PM |
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quote:
Originally posted by bumpy
quote:
Originally posted by Adamirish
I have the same gearing as you, 3.62 diff, type 9 and used to have 17's. It is fitted with a 1700 x flow. The engine is tuned, around 130bhp I
would imagine and that would easily spin the rear wheels from close to tick over. I would expect that with a pinto and the extra torque(mine has none)
it should still go well. Everyone's opinion on what power is acceptable is different though.
Have you done a compression test? Does the engine Rev cleanly? Fuel pressure good? I would suggest a trip to the rolling road and get the ignition and
fuelling set up.
I don't suppose you can remember what revs it pulled at 70mph?
Compression test is fine. The engine revs cleanly when the car is stationary and there is just the hint of a stutter when accelerating hard on the
road, but that is not what I define as sluggish.
I used to own a 1600 mk 3 Cortina and that pulled pretty well, by comparison.
Mine is somewhere between 2800-3000rpm at 70mph. It is now on 15" wheels with 195/50 tyres, the diameter difference between the 2 different sets
of wheels and tyres wasn't a lot, only half an inch or so. I know it is over geared but to be honest it is quite nice not to be revving the
balls out of it at motorway speeds. If progress is needed, I have 4 other gears to choose from. Going by how well mine goes with a not torquey engine
at all, especially in the lower gears I would expect yours to pull just as well, if not better than mine even with the gearing you have.
MK Indy 1700 Xflow
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Adamirish
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| posted on 7/9/15 at 10:47 PM |
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Out of interest, would you know what your car weighs? I was basing my opinion on it being a seven type car, forgive me if I've missed it but
what car is it?
MK Indy 1700 Xflow
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bumpy
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| posted on 7/9/15 at 10:54 PM |
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quote:
Originally posted by Adamirish
Out of interest, would you know what your car weighs? I was basing my opinion on it being a seven type car, forgive me if I've missed it but
what car is it?
Its a JBA Falcon. Probably a bit heavier than yours, but a lot lighter than a Sierra 
[img]
 
Nice piccy
[/img]
[Edited on 7/9/15 by bumpy]
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alfas
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| posted on 8/9/15 at 05:19 AM |
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you have around 30HP less than the MK, additionally 150-200kg more weight and your car is even more overgeared than the MK.
and i doubt that the MK is pulling well with this. its enough for the owner, but thats his point of view.
i´ve driven lots of x/flow powered sevens (mostly live-axled westfield ans sylva´s), compared to the MK those cars are again 100kg lighter and you
could feel instantly if the car had 13inch or 14inch tyres, a 3.54 or a 3.89 diff fitted...and none of those cars pulled well (IMO) with a 3.54 diff,
even with 13inch rims. all those cars had the typical tuning: double 40ies sidedraughts, between 1600 and 1700cc, fast road camshaft, stage 2 or stage
3 heads, balanced, lightend flywheel etc.
anyway.....for your JBA you need to stick in, at least, a 150HP engine for compensating that.
its up to you, but those 17" wheels look a bit too modern on such a "classic" body design (JBA Falcon), additioanlly your
suspension was not really constructed for such size of rims (unsprung weight, wider-rims--wider track--influence on handling and suspension geometry
etc)
go down to a classic design 14" wheel with high wall tyres ...and you would have sorted 2 problems:
the engine would pull better
the visual impression of the car would be improved (IMO)
its up to you: if you, under no circumstances, want to change the rims, than you need to find another solution.
you can try a 3,92 diff (IMO it will improve a bit, but will not solve your problem, so its another waste of time and money)
diff´s with a 4.x ratio arent available
an engine with at least 150HP costs money
the problem definately wont be solved by investing 10pound and 2h labour.
you can set 5times the ignition timing, 10 times the valve clearances, 4 times the camshaft timing...the problem is that your car is overgeared,
mainly caused by the rims.
[Edited on 8/9/15 by alfas]
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bumpy
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| posted on 8/9/15 at 07:39 AM |
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quote:
Originally posted by alfas
you have around 30HP less than the MK, additionally 150-200kg more weight and your car is even more overgeared than the MK.
and i doubt that the MK is pulling well with this. its enough for the owner, but thats his point of view.
i´ve driven lots of x/flow powered sevens (mostly live-axled westfield ans sylva´s), compared to the MK those cars are again 100kg lighter and you
could feel instantly if the car had 13inch or 14inch tyres, a 3.54 or a 3.89 diff fitted...and none of those cars pulled well (IMO) with a 3.54 diff,
even with 13inch rims. all those cars had the typical tuning: double 40ies sidedraughts, between 1600 and 1700cc, fast road camshaft, stage 2 or stage
3 heads, balanced, lightend flywheel etc.
anyway.....for your JBA you need to stick in, at least, a 150HP engine for compensating that.
its up to you, but those 17" wheels look a bit too modern on such a "classic" body design (JBA Falcon), additioanlly your
suspension was not really constructed for such size of rims (unsprung weight, wider-rims--wider track--influence on handling and suspension geometry
etc)
go down to a classic design 14" wheel with high wall tyres ...and you would have sorted 2 problems:
the engine would pull better
the visual impression of the car would be improved (IMO)
its up to you: if you, under no circumstances, want to change the rims, than you need to find another solution.
you can try a 3,92 diff (IMO it will improve a bit, but will not solve your problem, so its another waste of time and money)
diff´s with a 4.x ratio arent available
an engine with at least 150HP costs money
the problem definately wont be solved by investing 10pound and 2h labour.
you can set 5times the ignition timing, 10 times the valve clearances, 4 times the camshaft timing...the problem is that your car is overgeared,
mainly caused by the rims.
[Edited on 8/9/15 by alfas]
Thanks Alfas, its nice to hear from someone with so much experience. My head (and friend) tells me you are probably right 
Can someone have a go at answering this question, so I conclusively have a really clear idea of the problem. I cant find this stuff in text books.
My 'logic' tells me if a car is over geared then changing down a gear or two will eventually get to a situation where that becomes
irrelevant. For me it seems that an over geared car is a bit like constantly driving up an (unseen) hill causing sluggish performance. The solution
with a hill is to change down a gear or two until you can feel the engine become responsive and pulling you along nicely. If over gearing is my issue,
why cant I get that effect?
[Edited on 8/9/15 by bumpy]
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Ivan
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| posted on 8/9/15 at 08:38 AM |
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I would put it on a dyno to get a power curve - should quickly tell you if the problem is engine or gearing - if engine get it dyno tuned.
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MikeRJ
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| posted on 8/9/15 at 11:25 AM |
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quote:
Originally posted by bumpy
If the ign timing is increased a few degrees, the tickover speeds up and remains smooth, and the acceleration begins to pep up a bit.
BUT, at the position where the performance is satisfactory (but not startling) the engine becomes very difficult to turn over when starting. It has
all the symptoms of over advanced ignition with it appearing that the battery hardly has enough power to spin it over.
The vac advance retard is operating and the mechanical bob weights seem OK. Where do I go from here?
Do you have the correct distributor for the engine? The symptoms suggest insufficient total mechanical advance so increasing static advance improves
performance but makes it over advanced when starting. Pintos have a pretty crude combustion chamber shape in standard form, and require quite a fair
bit of ignition advance to work properly, you should be getting 32 degrees or more total advance at 3500 RPM.
Another possibility is you have the low compression engine as fitted to the Transit, these only made about 58bhp!
[Edited on 8/9/15 by MikeRJ]
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Ivan
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| posted on 8/9/15 at 11:56 AM |
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Another alternative is to get a phone app dyno - run the car from start on a safe piece of road - see what the zero to 60 time is and what the power
is calculated at - if it's above say 6.5 seconds and below 80 HP get it tuned by someone who knows what they are doing.
[Edited on 8/9/15 by Ivan]
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snapper
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| posted on 8/9/15 at 05:26 PM |
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You say GT cam?
Pinto GT engines were to all intents and purposes a standard 2.0 L with better exhaust manifold and a 32/36 Weber, that's it.
If your GT cam is aftermarket Bon Ford then you need to make sure the cam is timed correctly then look at ignition timing after that.
If it's an aftermarket cam it will be stamped on the cam end opposite end to the cam belt.
If it is a higher spec cam than standard to time it up you would need a vernier cam pully or the cam has been timed using the standard setting which
won't help how the engine revs.
Higher duration cams need a higher idle setting, more advance at idle and a quicker ramp from just off idle to 3600rpm
I have done several fast road Pinto's, the cheap option is
Pinto 2.0L injection head
Rhienz 1.3 mm gasket
FR32 cam or equivelant
You should see 130bhp and rev to 7k without issue
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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DW100
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| posted on 8/9/15 at 05:35 PM |
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And the brakes are definitely not permanently on are they?
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bumpy
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| posted on 8/9/15 at 06:01 PM |
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quote:
Originally posted by snapper
You say GT cam?
Pinto GT engines were to all intents and purposes a standard 2.0 L with better exhaust manifold and a 32/36 Weber, that's it.
If your GT cam is aftermarket Bon Ford then you need to make sure the cam is timed correctly then look at ignition timing after that.
If it's an aftermarket cam it will be stamped on the cam end opposite end to the cam belt.
If it is a higher spec cam than standard to time it up you would need a vernier cam pully or the cam has been timed using the standard setting which
won't help how the engine revs.
Higher duration cams need a higher idle setting, more advance at idle and a quicker ramp from just off idle to 3600rpm
I have done several fast road Pinto's, the cheap option is
Pinto 2.0L injection head
Rhienz 1.3 mm gasket
FR32 cam or equivelant
You should see 130bhp and rev to 7k without issue
Thanks Snapper, but I removed that GT cam from my car as it was of completely unknown origin and given that the carb and exhaust were standard it was
just giving me problems.
The car wouldn't tick over smoothly and generally messed about at lowish revs. With the now standard cam in place, tickover is perfect and the
engine is just much better behaved and tractable.
I am not looking for a fast road going car. If it had the same performance as a standard 2l Sierra I would be happy.
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alfas
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| posted on 8/9/15 at 06:57 PM |
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summary what you need to check and update us:
check brakes not binding
inform us about the engine-origin (possibly you will find an engine number)
check if the engine is really a 2l (maybe somebody put a 1.6L in?)
check advance curve of dizzy. do you have a strobe timing light? connect it, rev the car and tell us at which rev´s the advance stops and how many
advance you have.
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alfas
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| posted on 8/9/15 at 07:01 PM |
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do you know if the car is a single donor car (hence no q-plate)?
than the engine should be from a sierra?
good chance that an injection head is already fitted, but the injections system has been binned due to an easier installation of a downdraught
carb.
what year is the sierra from?
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rusty nuts
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| posted on 8/9/15 at 07:32 PM |
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As I pointed out over a year ago Bosche distributors suffer from seizing auto advance mechanism which would give exactly the symptoms you are
suffering
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bumpy
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| posted on 8/9/15 at 10:24 PM |
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quote:
Originally posted by alfas
summary what you need to check and update us:
check brakes not binding
inform us about the engine-origin (possibly you will find an engine number)
check if the engine is really a 2l (maybe somebody put a 1.6L in?)
check advance curve of dizzy. do you have a strobe timing light? connect it, rev the car and tell us at which rev´s the advance stops and how many
advance you have.
Thanks for sticking with this one .
The brakes are definitely not binding.
The engine is from the single donor car and is definitely a 2 litre
One or two have said that the dizzy advance retard could be faulty, so this is where I will put some effort. I have a strobe light so will measure
when things happen and will try setting at 32 deg advance at 3500rpm.
I can move the bob weights by hand and the mechanism seems to advance by about 0.5" at the circumference of the dizzy.
I can do a rough calculation assuming the dizzy has a diameter of 3"
Circumference is 7.8" which is 360 degrees. Therefore 0.5" equates to an advance of 23 degrees, which added to the initial setting of 10
degrees BTDC gives a total advance of 33 degrees. This seems about right but I will of course check it.
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alfas
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| posted on 8/9/15 at 10:31 PM |
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brakes fine
2L engine fitted
advance seems fine -- dizzy seams fine
so we are back at the beginninmg: overgeared
what year was the sierra?
are you sure its the sierra engine fitted?
was it an injection engine, converted to carbs?
what is the exact model of carb fitted?
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bumpy
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| posted on 8/9/15 at 10:41 PM |
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So we are back at the beginning: overgeared - looking most likely.
what year was the sierra?
are you sure its the sierra engine fitted?
was it an injection engine, converted to carbs?
what is the exact model of carb fitted?
Sierra was 1983
Yep have full build history
Nope, always been carb
Weber 32/36
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Irony
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| posted on 9/9/15 at 07:44 AM |
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Easy answer is to borrow a set of wheels that are smaller and yours. Fit them and see if it goes like stink. Surely someone on here lives near you.
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gremlin1234
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| posted on 9/9/15 at 09:50 AM |
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quote:
Originally posted by bumpyI can do a rough calculation assuming the dizzy has a diameter of 3"
Circumference is 7.8" which is 360 degrees. Therefore 0.5" equates to an advance of 23 degrees, which added to the initial setting of 10
degrees BTDC gives a total advance of 33 degrees. This seems about right but I will of course check it.
2.5" not 3" would give circ of 7.8"
remember also that the distributor runs at half the engine speed
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alfas
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| posted on 9/9/15 at 10:35 AM |
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quote:
Originally posted by Irony
Easy answer is to borrow a set of wheels that are smaller and yours. Fit them and see if it goes like stink. Surely someone on here lives near you.
good idea..and easy to realize!!!
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