FORD PINTO 2.0 - 2.1 SOHC

FORD PINTO 2.0 - 2.1 SOHC
ESCORT, CAPRI, SIERRA, GRANADA,
SPECIALS, KIT CARS
FOR ROAD, STOCK CAR,
RALLY OR RACE
INTRO...
Jem Engines are THE specialist engineers to the automotive, industrial and marine trades. Formed in 1974,
the company’s general engineering side supplies remanufactured industrial engines for Kubota and others,
with a range of specialist techniques in-house such as spiral welding and spark erosion which enable us to
deal with almost any automotive mishap! Yet, we also remain enthusiast at heart – you will see in our
showroom a restored Rolls-Royce V12 aero/tank engine among our display pieces, and we have rebuilt
many units from the past – Bentley, Coventry Climax, Riley, plus our own particular favourite, the Ford Pinto.
Ford launched their new Pinto engine in Mk3 Cortina in 1970, and pretty soon salesmen were racking up
high mileages in their GLs and Ghias and we began to get these engines in to be reconditioned. The Pinto’s
toughness and tuneability soon attracted the stock car fraternity particularly, so along with tuning for rally
and race RS2000s and Capris, the Pinto began to supplant the Crossflow for volume of work and became
quite a large part of JEM engines’ output. We developed a huge pool of knowledge of these engines and
helped develop several successful stock car and rally engines – their lead-footed drivers quickly finding the
base engine’s few weakness and demanding more and more (reliable) power!
This work continued strongly for almost two decades, gradually reducing at the end of the eighties as the
Pinto-powered cars’ values hit rock bottom and became uneconomical to repair. It never really stopped,
however, and it was unusual for the company not to have at least one Pinto in for rebuild, and a couple of
‘donor’ engines in the shed to supply components for customer’s unserviceable parts, but this was now just a
tiny fraction of JEM’s total output, and more modern engines, particularly diesels, were taking over the bulk
of the work.
We noticed, though, that when we were brought a modern-type engine in for repair, more of the components
would be unusable compared to older units like the Pinto. For instance, a blown head gasket would result in
overheating, and in an aluminium engine a warped head would frequently be unrecoverable, and quite
often the head bolts would stress the threads in the block resulting in a scrap block too – very expensive!
we have supplied
Pinto engines to the
following countries:
Perhaps this is one reason for the revived interest in the all-iron Pinto.
Lately, JEM have been reconditioning more and more Pintos till now we are putting out 5-6 per month as
short or “long” motor (with head and camshaft fitted).
We now run a series of monthly evening demos showing rebuild techniques – block rebuilding, head work
and camshaft installation.
The Pinto’s renowned strength and durability make it an ideal choice for an economical track day car, and
for a simple and cheap kit car project. A huge amount of tuning gear is available and a large pool of
expertise makes tuning for more power simple and affordable. The classic car movement is returning to the
advantages of the Pinto, JEM having supplied several engines for owners returning their cars to standard, in
one case replacing Vauxhall power in an RS2000! In another case, a Pinto was ordered for installation in a
kit car which was being crated for shipment to South Africa by the customer who was emigrating. We have
now exported Pintos to 10 different countries.
It is a fact that the ‘carbon footprint’ of a reconditioned engine is about one tenth that of a new engine when
you take into account energy use on new castings, machining and shipping, though we surely don’t have to
preach to the classic or kit car enthusiast about the benefits of recycling, but we believe the Pinto’s green
credentials are assured and that it will soldier on in enthusiasts’ cars for many years.
CONTENTS
Section 1
Donor engine
page
3
Section 2
Cylinder Block Machining
page
4-5
Section 3
Crankshaft and Conrods
page
6-7
Section 4
Pistons
page
8
Section 5
Clearance Checks
page
9
10
Section 6
Engine Assembly
page
Section 7
Cylinder Head
page 11-13
Section 8
Replacement Components
Page 14-15
ANY OLD IRON...
First find your donor engine. This might come from your own well looked-after classic, or from a
mouldering old Transit in a scrapyard, but due to the scarcity of good Pinto base units now, we
really much prefer to have a unit supplied to us in exchange for a rebuilt unit, otherwise we have
to impose a hefty surcharge.
The original unit’s components must be sound and capable of reconditioning - holed blocks,
snapped crankshafts or cracked heads are unacceptable and will be subject to surcharge. We will
usually rebuild your own engine which can take up to 3-4 weeks, though we can generally supply
a unit from stock within 1-2 weeks. Specialised repair can sometimes be undertaken to recover a
damaged block if it is necessary to retain this for originality reasons.
Old units are dismantled in our workshop, all useable components are pre-cleaned for inspection,
then the block, crank and conrods are passed through special chemical dips which remove paint,
carbonised oil and scale.
Now we can start the rebuilding process...
page 3
BUILDING BLOCKS...
The cylinder block is the core of any engine build, and JEM’s attention to detail starts here.
First, the block ends are refaced. This is purely for cosmetic
reasons but is vital to give the finished unit that “as new”
look. The crankcase sump face is also resurfaced, this with
a rough cut and fast machine rate to give an ideal grip for
the cork casket to ensure a good seal.
*JEM TIP don’t use any
sealant except at the
Block end being refaced
ends of the cork gasket where they butt to the flexible
plastic bows - a small blob of RTV type sealant should
be used here. If the cork casket needs to be secured
in position during assembly, use a few tacks of
impact adhesive.
The top block face is
usually fly cut, a single
tool milling operation
which leaves a
surface finish
perfect for good
head gasket sealing
page 4
top surface being refaced
THE BORING BITS...
continued
It is likely that stresses in the
manufacturing processes and years of
use have resulted in slight distortion of
the cylinder block. Line honing ensures
that the main bearing’s housings are
precisely in line for minimum friction and
a reduction in bending stresses on the
Line boring of main bearing housings
crankshaft. For this reason, all five main bearing caps have their joint faces lightly ground so that
there is sufficient metal to allow honing. The caps are fitted to the block and torqued to
manufacturer’s specification, measured to check there is enough stock for honing to correct
alignment tolerance of less than half a thousandth of an inch. Roundness is kept to 0 to 0.0003”
(three ten thousandths of and inch)
Cylinder boring
The block is set up on our semi-automatic boring machine and the cylinders are bored to within
0.003” (three thou) of finished size. On completion of this process, the block is then transferred to
our honing machine. It is important that the main
bearing caps are installed and torqued prior to
finishing the bores as the bores can become
distorted when the bearing caps are torqued.
*JEM TIP it would be pointless finishing
the bores round and parallel to with
0.0002” (two tenths of a thou) without
the main caps in place as this distortion
can be as much as 0.002-0.003” (two to
three thou). To maintain roundness and
page 5
parallelism the cps MUST be fitted.
Cylinder honing
BACK TO THE GRIND...
Following a visual inspection, the crankshaft
is set up on vee blocks to check for
straightness, then the main bearing and
crankpin journals are measured to ensure
they are suitable for regrinding. At this time
the condition of the front snout and flywheel
bolt-hole threads, and the front keyway are
checked too. The crank is then set up on the
re-grinding machine and reground to take
the required undersize of shell bearings. The
front and rear oil seal tracks are also very
lightly ground, removing the minimum of
metal, to ensure zero run-out between
bearing journals and the oil seal track to ensure they are concentric.
At the back of the crank, the flywheel mounting flange is also ground to reduce flywheel run-out.
On completion of the grinding process, the oil-holes are lightly honed to eliminate sharp edges on
the journal surface and allow the spread of lubrication across the bearing surface. All bearing
journals are polished to the correct finish for good bearing life.
Each crankshaft is subjected to a magnetic particle Non-Destructive Test (NDT) where any cracks
are detected under ultra-violet light.
page 6
RODS AND ENDS...
continued
Each conrod is checked for suitability, eg
bend, twist or heat damage.
Approximately 3 thou is ground off the rod
and cap joint faces, then they are bolted
together to the manufacturer’s
recommended torque. The big end bore is
measured to ensure that when honed,
Precision grinding
bearing cap joint face
the roundness of the bore is
maintained to 2 tenths of a
thousandth of an inch. The conrods’s
small end is milled on each side to
allow the fitting of the new 93mm
piston (2.1 version only.
Our Sunnen LB1810
precision honing machine
ARP conrod bolts are fitted prior to
resizing on our Premium-Plus range
of builds
page 7
Conrod bore size
and roundness check
Milling conrod eye
(2.1 build only)
PISTONS...
We mainly use Mahle pistons for all
2.0 litre applications (stock car), while
93mm diameter pistons are used to give the
nominal 2.1litre capacity.
We choose a high quality proprietary
piston in aluminium alloy cast with integral steel reinforcing struts. These plates control the
expansion of the piston body and allow less piston-to-bore clearance than with traditional all-alloy
pistons. This stiffens the piston body, reducing the risk of fatigue cracks and cuts down piston noise
(known as ‘slap’) especially on start-up. The piston pins (gudgeon pins) are of the semi floating type
and are retained by a transition fit in the eye of the conrod. There are two methods of fitting the pin
to the conrod:
1. Support the piston on a shaped bolster and press the gudgeon pin through the piston and
conrod small end eye to the correct position. JEM TIP: damage often occurs when using this
method, and distortion of the piston (highly likely) will result in increased wear and early
failure. Don’t use this method!
2. The correct way is to use the specially designed fitting
equipment which we have installed. Here the conrod eyes
are placed in special timed heater cells until the conrod
expands and allows the gudgeon pin to be gently pushed
into the correct position in the eye. As soon as the pin is in
the rod eye, the rod begins to cool and contract so the fit is
page 8
complete without any stress to the piston.
JEM unique ID
CHECKS AND
BALANCES...
page 9
At this stage, the individual components are
brought together for running clearances to
be checked.
Each crankshaft is uniquely etched with the
bearing undersizes, the JEM machinist’s
identity, and the date to aid future rebuild
and to guarantee authenticity.
Conrods are fitted to the
crankshaft so that bearing
running clearances (radial) can
be checked using plastiguage,
and conrod free end play (axial
clearance) is measured.
The crankshaft is fitted to the
block and main bearing
clearances are measured and
crank end float is set up.
Each piston’s running clearance is measured relative to its
cylinder, then they are fitted to the conrods, using special dummy
gudgeon pins, and installed in the block. Each is set precisely to
TDC and the piston height is measured relative to the top of the
block to determine the amount of metal to be removed from the
top of the block.
All components are disassembled, the crank and rods are
balanced and everything inspected for final cleaning
GENERAL ASSEMBLY...
Piston are fitted to conrods as previously
described. When crank and rod assemblies are
fitted to the block using appropriate big end and
heavy duty competition trimetal main bearings,
each conrod nut is secured with Locktite. (Where
Bolt seal
Oil pump
ARP bolts are required, the appropriate lubricant
is used.) Block end and sump faces are lightly
coated in clear lacquer. Oil seals and rear crank
seal are fitted with the application of the
relevant sealant. The auxiliary jack shaft is
installed and the running clearance checked.
Front end
Dowels
The front seal carriers are fitted and the two
timing belt pulleys are fitted. Sealant is applied
to the core plug bores and new plugs are fitted.
Rods and pistons are stamped with their
appropriate cylinder number. Mains and rod
fasteners are paint spotted after final torquing
page 10
Bore finish
Flywheel
HEAD CASE...
In the case of the standard Pinto cylinder head,
Head/manifold face resurface
the assembly is dismantled, cleaned and
inspected, including crack testing. We always
recommend that new reciprocating components valves, springs, camshaft, bearings, followers etc are used. Machining is undertaken with the same
meticulous attention to detail as the block – both
manifold faces are lightly machined to ensure flat
surfaces for a positive seal at the manifold joints,
and the head-to block face is machined to give
the required compression
Pressure test
ratio and achieve a flat
surface for correct seal of
the head gasket.
page 11
Valve spring tension
BIG VALVE ...
continued
To extract the most power from the Pinto engine, the
JEM big valve head is the way to go. Following the
cleaning and testing as detailed in Section 7, the
valve guides are first to receive attention.
The standard head’s valves run directly in the cast
iron head, but to correct wear and allow better
lubrication, the JEM head uses special bronze valve
guide inserts. These are fitted
into position and a
succession of broaches are
used to expand the guides
until the required gauge is
achieved.
JEM TIP: because the exhaust valve runs
hotter than the inlet, it requires a greater
running clearance.
In our unleaded version, special hardened exhaust
valve seats are fitted to enable the use of unleaded
fuel. Specialised equipment is used machine a
counterbore to a precise diameter and depth. The
new valve seat insert is fitted and the profile of the
page 12
seat is cut to give throat, valve and clearance angles.
CHAMBER/PORTS...
continued
On our big valve cylinder heads the
ports and chambers are reworked to
high and precise standard. On
completion of the combustion
chamber rework, each chamber
volume is checked to give an accurate
compression ratio across the four
chambers.
JEM ENGINES PINTO 2.0/2.1 BIG VALVE HEAD...
SPECIFICATION
Inlet valves 44.5mm (std length) EN32 4N material
Exhaust valves 38.5mm (std length) EN21 4N material
Exhaust ports fully ported
Inlet ports fully ported
Casting pressure tested (Hot)
8 bronze valve guide liners fitted
Valve seats triple angle cut
Unleaded seats fitted to exhaust positions in unleaded versions
Manifold joint faces fully machined
Cylinder head ends machined
Main gasket face machined
Combustion chambers volume balanced
New bronze cam bearings fitted
Competition valve stem seals fitted
Modified valve springs caps used
Competition single valve springs (Kent VS 9)
New core plug at rear
Fully chemical cleaned (Hot)
Our cylinder heads are produced to the highest standards in both workmanship
and quality of parts used. A lead free version of these heads is available .
The compression ratio will be determined after discussion with the customer as we
need to know the cylinder bore size and each head is customised to the customer’s
requirements. These cylinder heads are only sold on an exchange basis and either
with the later injection style inlet ports or the earlier round style port. The cylinder
head in the picture is a library picture and not the actual head on offer but for
appearance the head supplied will be to the same standard as shown.
We prefer to discuss the head with the customer prior to supplying it so that we
can give the desired compression ratio.
page 13
THE BEST BITS...
We use only the best components from
recognised suppliers and manufacturers
of acknowledged quality and reliability.
We never use cheap unproven
components as this is a false economy
which can put the entire engine at risk to
save just a few pence. Our machining
and parts specifications may change to
take account of improvements or parts
availability.
page 14
THE WORKS...
The following pages detail the five most popular specification levels which have become our
‘standard’ range. While we are sure one of these will suit your particular application or budget,
we are always ready to discuss you individual requirements.
JEM 2.0/2.1 BASIC BUILD SHORT MOTOR...
SPECIFICATION
Rebored and hone cylinders
Pressure test block water jacket
Line hone main line
Resized 4 con-rod large end bores
Regrind crankshaft & lap
Balance reciprocating and rotating
components
Machine block top face to required
height
Fit 3 core plugs & spigot bearing
Fit rear crank seal
Paint block sides
Assemble short motor as per
described procedure
Basic build description:- the basic build short motor has all the critical machine work carried out with
the exception of the block ends and sump face not being machined. The front aluminium seal
carriers are not fitted, however the short jackshaft is installed. The block will not be of 205 origin in
most cases, but the conrods will be of 205 type. The bottom gasket set is included.
JEM 2.0/2.1 PREMIUM BUILD SHORT MOTOR...
SPECIFICATION
2.0 & 2.1 premium build
short motor (Based on 205 block)
Rebore & hone cylinders
Fit 3 core plugs & spigot bearing
Machine both block ends
Pressure test block water jacket
Machine block sump face
(coarse cut)
Line hone main line
Lacquer machined block ends
Resize 4 con-rod large end bores
Paint both block sides
Regrind crankshaft and lap
Supply complete lower gasket
Balance reciprocating and
rotating components
Paint (black) both from seal carriers
Machine block top face to
required height
Basic build description:- Assemble short motor as per described procedure incl rear oil seal and front
oil seal carriers, also fit crank toothed belt pulley and aux shaft drive pulley (painted black)
JEM 2.0/2.1 PREMIUM PLUS SHORT MOTOR...
SPECIFICATION
This is the same spec as the premium build short motor,
however the premium plus is fitted with arp heavy duty
competition conrod bolts
JEM ENGINES PINTO 2.0/2.1 LONG MOTOR...
SPECIFICATION
Performance camshaft
Performance cam followers
Performance valve springs
Long ball studs
Alloy vernier pulley
Timing Belt
Water pump
Refurbished alloy RS sump
Head bolt set
Oil spray bar
External stainless steel cap screws
Dowel and modified flywheel
Ignition cable clips
Oil filter
High pressure oil pump
High tensile oil pump valve
Our Ford SOHC 2.0/2.1 Long motor is built to the highest standards. These units incorporate our
popular 2.0/2.1 Premium Plus short motor and big valve cylinder head (now unleaded). An
unleaded version is available at a small additional charge.
Each engine is assembled in a meticulous and methodical manner, adhering to all critical limits and
fits, all valve lifts are measured and any corrections to lifts are adjusted by tipping the valves.
The camshaft is set up and precisely timed using a vernier hub. On completion of the assembly an
oil pressure test is carried out by externally driving the oil pump drive spindle. Great care is taken
to enhance the engine’s presentation throughout the build.
Our 2.0/2.1 Long engines are only available on an exchange basis. The returned engine must arrive with us prior to
release of the newly built engine. the old unit will be required at least 3 working days in advance of despatch. This is to
allow us time to dismantle the unit and evaluate the acceptability of the components. The old unit must be complete as per its
supplied replacement. If an alloy RS2000 sump is being returned, it must be in useable condition - no weld repairs or
unacceptable dents or gouges. The flywheel must be RS2000 or Sierra style and must not have been previously modified.
Engines are only supplied on a like for like basis, i.e 205 for 205, or early 2.0 for early 2.0.
JEM ENGINES OVAL CIRCUIT “F2” CORE ENGINE...
SPECIFICATION
Block assembly
Rebore and hone cylinders
Cylinder head assembly
Cylinder head
Pressure test block water jacket
Pressure test water jacket
Resize four conrod large end bores
Machine & fit inlet & exhaust
bronze guide liners
Balance reciprocating and
rotating components
Machine block top face to
required height
Fit three core plugs and a
spigot bearing
Machine and lacquer both
block ends
Paint block sides
Paint (black) both front oil
seal carriers
Assemble short motor as per
described procedure inc. rear oil
seal and front oil seal carriers,
also fit crank toothed belt pulley
and aux shaft drive pulley
(painted black)
Modify valve guide boss as
per regulations
Profile and cut eight valve seats
Machine both sides of cylinder head
Machine main face of cylinder head
to achieve required combustion
chamber volume
Remove and fit three camshaft
bearings
Fit new core plug to rear of
cylinder head
Measure, machine and set valve
spring fitted heights
Measure, machine valve lengths to
achieve correct lift
New parts include:
4 Mahle piston assemblies
5 pairs of tri metal competition main
bearings
4 pairs of tri metal competition conrod
bearings
1 pair of crankshaft thrust washers
1 high pressure oil pump exhaust valves
4 inlet valves
4 exhaust valves
8 bronze valve guide liners
4 core plugs
1 top gasket set (elring or payen)
1 lower gasket set (elring or payen)
1 timing belt
1 timing belt tensioner
1 vernier cam pulley
1 cam spray bar
1 camshaft (jem spec)
8 cam followers
8 valve springs
1 spigot bearing
10 cylinder head bolts
1 water pump
1 oil filter
1 oil pump drive spindle
The core engine is a premium plus built short motor with the cylinder head assembled with the valve
timing checked, adjusted and set. The cylinder head is assembled with the camshaft and followers,
the valve lifts are measured, in most cases simply installing a camshaft with its associated valve train
is not enough. When the new cam kit is installed it is not uncommon for the actual valve lift to be as
much as 2.0mm or more shy of book lift.
When jem assemble a head we measure the valve lifts and achieve optimum lift by machining the
tips of the valves individually, assembling and measuring the lifts until the desired lift is achieved.
Laborious, but has huge gains in performance.
The short motor is assembled per our standard assembly procedure detailed in our work procedures
explanation which is attached under premium build short motor 2.0 or 2.1ltr.
The complete prepared cylinder head assembly is fitted to the short motor and the camshaft is
precisely timed to the crankshaft incorporating a vernier cam wheel.
In conclusion the core engine is a short motor with a prepared cylinder head fitted and the valve
timing set, also includes a high pressure oil pump fitted.
To complete this engine all that is required to fit is oil pick up pipe and sump, a rocker cover and all
necessary ancillaries, manifolds, carb, distributor and flywheel. All necessary gaskets are provided
with the core engine.
FORD PINTO 2.0 - 2.1 SOHC
ESCORT, CAPRI, SIERRA, GRANADA,
SPECIALS, KIT CARS
FOR ROAD, STOCK CAR,
RALLY OR RACE
JEM ENGINES
23 Polmont Road
Falkirk
Scotland
FK2 9QQ
Tel 01324 633266
Fax 01324 633870
info@jemengines.co.uk
www.jemengines.co.uk