Sounds like 2 countries separated by a common language, on this side of
the pond the Pinto engine always referred to the OHC engine as fitted to
know the Kent OHV was fitted to the Pinto but basically your mate has
the Kent OHV engine in his Lotus 7 by the sound of it. I know an engine
machinist that specialises in the Lotus twin cam, BDA, and some Ford
Kent Xflow head work and he didn't seem too traumatised when I met up
with him again recently but he did mention that the twin cam blocks
differed from the standard blocks as they were beefier and marked with a
big L on the block casting and maybe other changes for reliability. An
ex racing driver I used to know told me about head work on the old Aston
Martin straight 6 engines and why so few people wanted to work on them
as apparently they have no shims and the valves stems have to be ground
or the seats cut to get the gaps right, makes the FIAT system with the
shims on top of the bucket tappets a dream, IIRC VAG adopted it under
license and a mate mentioned that even Ford don't use hydraulic tappets
on some engines these days as when shimmed in manufacture they last
which was my experience on the FIAT engines when maintained.
A Toyota 3tg would be nice - or a twin-cam ford Escort or Zetec from
a ZX2. The 3TG is hard to find over here but was a HOT engine in the
Celoca RT series rallye cars - - -1600cc of DYNAMITE
e:
r requirements, it's hard to beat Hondas for most of them. Japanese law req
uired that engines be changed at 40,000 miles a decade or so ago, which put
a lot of used ones on the US market. Moderate speed equipment is readily a
vailable.
e beautiful. One had a Veloce head with twin side-draft DCOE Webers. I don'
t know of anything that looks that good today, but it's hard to tell until
you get all of that plastic junk off the top of them. I own a 2018 Subaru C
rosstrek, and I've seen it with the plastic off of it. Not exactly a thing
of beauty, but I do like the engine.
g is antithetical to sports-car type responsiveness, unless you spend megab
ucks. Garden-variety turbos are not sporty engines. They just wind up -- ev
entually -- and put out a lot of power. In a light sports car, you don't ne
ed that much.
are a lot of good engines out there today. Your project is one I've dreamed
about off and on over the years, and having done some sports-car racing be
tween 1967 and 1972, I have a good idea of what I'd want my engine to be go
od at if I ever did it. I'd look at Honda, Toyota, and Nissan. If one dropp
ed in my lap, I'd look at a 3-Series BMW. But I'd make sure that aftermarke
t parts are readily available for anything I chose. Oh...and make sure you
can mate it up with a transmission for rear-wheel drive. Maybe an engine th
at's used in a small pickup.
Locost, at least one was powered with a Honda Fireblade (CBR 1000RR, 998 cc
) motorcycle engine, and the report was that it was faster than a Locost po
wered by a Rover V8 (essentially the old 215 cu. in. Oldsmobile aluminum V8
).
iginal Lotus 6 (soon to be Lotus 7) came out, you could put any engine in i
t that you wanted. Lotus would deliver them with 948 cc Morris engine or a
Ford Anglia. Neither one put out more than 50 hp in stock trim, but they we
re race winners.
US, and he has a 1600 cc Ford Pinto engine it it. That's essentially the s
ame engine as the English Ford 125E New Kent -- probably the most common en
gine in Lotus 7s. I've driven it; it probably doesn't have more than 100 hp
, but it weighs less than 1300 lb. and it goes like hell.
relaxing to drive. It doesn't take much power to make those little space-fr
ame club racers really run. But it has to suit *you* or it isn't worth the
trouble.
cc pushrod -- essentially the English Ford New Kent -- or with the 2.0 - 2.
3 liter SOHC engine (that had too few oil holes in the crankshaft, and tend
ed to burn up main bearings ). I know both engines from personal experie
nce -- mostly bad. d8-)
which had a hollow crankshaft. I owned one car with a 115E and worked on a
friend's car with the 109E. I was very familiar with the whole series. The
and wound up being the basis of more sports-car and racing engines than, pr
obably, any other. Aside from the short stroke, there was nothing unusual a
bout them, but they were pretty sound and had a lot of horsepower potential
.
ross-flow Kent, and, to my misfortune, the twin-cam Lotus version, from whi
ch I ran as fast as I could. d8-)
cold-lash the valves on a Bristol engine, all sorts of things showed up in
my driveway on Sunday afternoons. They thought I was a magician. Tney were
wrong. I just had an English mechanic friend who knew all the tricks, and
was very patient in teaching me.
n't
Yes, that pushrod Kent was the basic engine in the Pintos sold in the US. M
y roommate thought it would be cheaper and easier to put one in his Lotus,
but then discovered that the wiring was all wrong, and he wound up spending
more than he would have if he had left the twin-cam in it. d8-) But he sti
ll has the car, which he bought in 1971, and he can still get parts, so may
be he wound up better overall. I doubt if more than a dozen or two Mk. 4s a
re left in the US.
As for grinding valve clearances, since you're British, you may remember ho
w you adjusted valves in the old flathead Ford Anglias. You had to surface-
grind the lifters. Ouch. They may have changed that just before they went t
o the 105E overhead-valve engine.
As for Lotus twin-cams, you have to know what you're doing. If the chain dr
ive isn't properly loaded when you're adjusting valves, you get all screwed
up. I never learned how to do it. Fortunately, I didn't have to.
One more point on the 6-cyl Aston-Martin: The owner's manual included instr
uctions for de-coking the heads. Yike. Welcome to the 1930s.
From what I've heard, valve adjustment is a rare thing these days. That's g
ood. I hated getting covered with hot motor oil, and my dad would raise hel
l when he saw all the oil on our garage floor.
The beauty of roller cams and overhead cams - few moving parts with
little wear potential - and hardened seats that don't attempt to bury
the valves in the head - - -
The advances that have come with unleaded fuel have reduced engine
maintenance and extended engine life SIGNIFICANTLY - add the
advantages of electronic engine control and efi - and then compound
that with adjustable valve timing and direct injection and the
performance potential has also skyrocketed. Compression ratios that
were unheard of only 15 years ago can now be run on regular pump gas
and turbo engines can be run with CRs that were borderline on NA
engines not that long ago.
Another good engine, if he can find one, is the twin-cam Toyota "A"
series engine from the old EA86 SR5 - or a Mazda Miata 1800. On a
light car like a Lotus 7 clone you don't need to turbo it - but the
turbo lag is not very noticeable with a light racing flywheel on a
fly-weight vehicle. A friend used to race a "lightweight" Miata with a
turbo on it and he was VERY competetive.It was down well under 1400
lbs in racing form and gave a lot of high-buck sports racers a good
run for their money. Didn't need the turbo at the bottom end and
really didn't NEED it at the top end either - but it made life
interesting - - -
That was after the 3 cyl turbo "zook" (1988 Suzuki Forsa) - (same as a
Chevy Turbo Sprint or Pontiac Turbo Firefly) which was also a real
handful.
rote:
ther requirements, it's hard to beat Hondas for most of them. Japanese law
required that engines be changed at 40,000 miles a decade or so ago, which
put a lot of used ones on the US market. Moderate speed equipment is readil
y available.
were beautiful. One had a Veloce head with twin side-draft DCOE Webers. I d
on't know of anything that looks that good today, but it's hard to tell unt
il you get all of that plastic junk off the top of them. I own a 2018 Subar
u Crosstrek, and I've seen it with the plastic off of it. Not exactly a thi
ng of beauty, but I do like the engine.
lag is antithetical to sports-car type responsiveness, unless you spend me
gabucks. Garden-variety turbos are not sporty engines. They just wind up --
eventually -- and put out a lot of power. In a light sports car, you don't
need that much.
re are a lot of good engines out there today. Your project is one I've drea
med about off and on over the years, and having done some sports-car racing
between 1967 and 1972, I have a good idea of what I'd want my engine to be
good at if I ever did it. I'd look at Honda, Toyota, and Nissan. If one dr
opped in my lap, I'd look at a 3-Series BMW. But I'd make sure that afterma
rket parts are readily available for anything I chose. Oh...and make sure y
ou can mate it up with a transmission for rear-wheel drive. Maybe an engine
that's used in a small pickup.
he Locost, at least one was powered with a Honda Fireblade (CBR 1000RR, 998
cc) motorcycle engine, and the report was that it was faster than a Locost
powered by a Rover V8 (essentially the old 215 cu. in. Oldsmobile aluminum
V8).
original Lotus 6 (soon to be Lotus 7) came out, you could put any engine i
n it that you wanted. Lotus would deliver them with 948 cc Morris engine or
a Ford Anglia. Neither one put out more than 50 hp in stock trim, but they
were race winners.
the US, and he has a 1600 cc Ford Pinto engine it it. That's essentially th
e same engine as the English Ford 125E New Kent -- probably the most common
engine in Lotus 7s. I've driven it; it probably doesn't have more than 100
hp, but it weighs less than 1300 lb. and it goes like hell.
re relaxing to drive. It doesn't take much power to make those little space
-frame club racers really run. But it has to suit *you* or it isn't worth t
he trouble.
00 cc pushrod -- essentially the English Ford New Kent -- or with the 2.0 -
2.3 liter SOHC engine (that had too few oil holes in the crankshaft, and t
ended to burn up main bearings ). I know both engines from personal expe
rience -- mostly bad. d8-)
5E, which had a hollow crankshaft. I owned one car with a 115E and worked o
n a friend's car with the 109E. I was very familiar with the whole series.
s, and wound up being the basis of more sports-car and racing engines than,
probably, any other. Aside from the short stroke, there was nothing unusua
l about them, but they were pretty sound and had a lot of horsepower potent
ial.
, cross-flow Kent, and, to my misfortune, the twin-cam Lotus version, from
which I ran as fast as I could. d8-)
to cold-lash the valves on a Bristol engine, all sorts of things showed up
in my driveway on Sunday afternoons. They thought I was a magician. Tney w
ere wrong. I just had an English mechanic friend who knew all the tricks, a
nd was very patient in teaching me.
didn't
. My roommate thought it would be cheaper and easier to put one in his Lotu
s, but then discovered that the wiring was all wrong, and he wound up spend
ing more than he would have if he had left the twin-cam in it. d8-) But he
still has the car, which he bought in 1971, and he can still get parts, so
maybe he wound up better overall. I doubt if more than a dozen or two Mk. 4
s are left in the US.
how you adjusted valves in the old flathead Ford Anglias. You had to surfa
ce-grind the lifters. Ouch. They may have changed that just before they wen
t to the 105E overhead-valve engine.
drive isn't properly loaded when you're adjusting valves, you get all scre
wed up. I never learned how to do it. Fortunately, I didn't have to.
structions for de-coking the heads. Yike. Welcome to the 1930s.
s good. I hated getting covered with hot motor oil, and my dad would raise
hell when he saw all the oil on our garage floor.
Very true! They've reached extraordinary heights of engineering sophisticat
ion. Just in time to be replaced by electric motors. d8-)
ANd contrary to what you would expect, the reliability has IMPROVED
with the sophistication, not decreased. Generally the more complicated
you make something the more goes wrong. Today it is well within the
realm of "normal" for an engine to go 1/4 million miles without ANY
repairs - simply change the spark plugs every 100,000 and the oil
every 10,000 - the fuel and air filters a few times and mabee a belt
or hose or two -- -
Used to be 1HP per cu inch was the holy grail - now 2 is getting
pretty common - like 197 hp out of a 1.3 liter turbo hyabusa - that's
just under 80 cubic inches and 2.46 hp per cubic inch!!!!!
Yeah, I thought about a Bug engine. And I know all about those ring
gear swaps. The transaxle from a bus had the ring gear swapped to the
other side because the buses had a gear reduction on each wheel. So to
put a bus transaxle in a Bug the gear needed swapping.
Back to bug engines. I drove bugs for years and really know them
inside out. But I also trashed a few engines being plain too hard on
them. And they're air cooled. I want heat in the winter.
Eric
Try to find one cheap. There's a guy down the road into town who
rebuilds rice burners and an entire, multicolored, multiyeared MR-2
car lot sits out front of it in various states of dismantle. He
probably has the grabs on everything MR-2 in this half of the state.
Sounds like fun, Eric. Suggestion: Make friends with a local bodyman
and offer to help him out a few hours/day, a day or 2 a week, in
return for him teaching you how to wheel. They're likely to know
where to find flat sheet for bodywork, too.
Your best bet is to find a blingable drive train you like and then
build what you want around it. Have you read all the sheet metal and
fab books yet? A few:
Paint & Body Handbook by Don Taylor and Larry Hofer
Ultimate Sheet Metal Fabrication: Build from scratch with aluminum and
steel. by Timothy Remus (English wheel info)
Sheet Metal Handbook: How to form and shape sheet metal for
competition, custom, and restoration use. by Ron & Sue Fournier
Let us know what you settle on. I'd love to follow your build, having
had the same hankering long ago.
I did too, until I helped build a batch of prototype electric cars and
saw how many little things had to be just right. I still don't
understand the subtleties of caster and camber and kingpin
inclination. Fortunately [a racing chassis expert] was on the team.
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