dai1983
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| posted on 21/8/13 at 08:11 AM |
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J15/vectis owners
Could you please tell me what power and weight you are running with?
Obviously I'd like the biggest power to weight for my budget so unsure whIch way to go. I've spoken to Jeremy and apparently the MGF
subframe adds 20kg to the build but gives a much stiffer chassis. The MGF kit is also £1000 cheaper and uses a lot more parts from the donor car and
the k series comes in 160bhp vvc.
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Jenko
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| posted on 21/8/13 at 08:36 AM |
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Ive opted for a puma engine with the IB5 gearbox in my J15, mainly because I'm trying to keep the car as light as possible. I enjoy the small
twisty airfield tracks) .The end game is to fettle the engine to around 160bhp which should be do-able with throttle boddies and different cams (and a
decent ecu). I've also managed to squeeze on some very light 13 inch wheels. Anything around 300bhp / ton is going to be interesting.
I know others have gone duratec which is going to instantly give you much better power, it's a bit of a squeeze, but it's a cracking
engine and fairly light.
As for the mgf giving a much Stiffer chassis...Maybe...........the j15 / riot / mojo chassis is inheritly a good one and I've never heard of
anyone complaining of it flexing. What I'm saying is I'm not sure what advantage you would see.
The other thing to consider, is the 20 kg weight is in an area where most of the weight is already...That said, it really depends what you are going
to use the car for....if you are planning to put it on track mostly, then if it were me I would go the j15, else either / or is still going to be
cracking car....For max power to weight, I think the duratec install is going to be hard to beat.
Of interest, I've recently pickup my image split rims, and did some comparisson weights with some other wheels.
Caterham 6J 13 wheel and tyre – 12kg
Puma 6.5j 15 wheel and tyre – 14.5kg
Team dynamics (not sure what model 7j 15 wheel and tyre – 17kg
Image split rims 7j 13 wheel and tyre – 10kg
Point being, it is possible to loose a fair amount of weight in other areas...split rims looses a total of 28kg unsprung weight over larger 15 x 7
rims.
[Edited on 21/8/13 by Jenko]
MY BLOG - http://westfieldv8.blogspot.co.uk/
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dai1983
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| posted on 21/8/13 at 09:20 AM |
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Thanks for the reply. The car will be used about 99% of the time on the road. I do like the idea of using the most amount of parts possible from a
donor and a grand saving on the initial price is hard to ignore. As you say though the extra weight is towards the rear and it would have a k series
fitted which is another discussion altogether.
It's interesting to know the wheel weights as I thought the caterham ones would be very light. How did you have trouble squeezing them on?
Passat caliper clearance? I'd love to see photos of them fitted.
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theprisioner
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| posted on 21/8/13 at 11:10 AM |
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I am also running the Ford Sigma in my J15 and I am very pleased with it. I don't know exactly what power I am getting but in the order of
140bhp (needs another rolling road report) running the standard ecu and some enhancements form the mechanicals and PumaSpeed ecu upgrade. I will have
it remapped now that the ecu has learned the new settings. The weight is about 625Kg. The chassis is brilliant I would not consider adding another
20kg from the donor. The road holding is awesome as it is.
http://sylvabuild.blogspot.com/
http://austin7special.blogspot.co.uk/
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Jenko
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| posted on 21/8/13 at 11:19 AM |
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Clearence on the rears is a well known J15 issue. The VW calipers are nice and light, but also quite large, but yes, I used them and had to shave off
the cooling fins.
the caterham wheels are light, it's the split rims are lighter....
The k series is a nice light engine anyway, so that helps.
MY BLOG - http://westfieldv8.blogspot.co.uk/
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deeceee09
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| posted on 21/8/13 at 11:31 AM |
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I am running a Duratec with roller barrel TBs, Kent's mildest cams and an Emerald ECU in my J15. 210 bhp at 7800 rpm and car comes in at 550 kg
so just over 380 bhp per tonne. Could do with more (one of my sprint competitors has about 500 and something bhp per tonne via a supercharged Zetec
in his Phoenix) but will concentrate on getting the handling and gearing sorted out first. For road use 210 bhp would be more than plenty IMHO. I am
using the MTX75 box for strength but I guess the IB5 one would be fine for road use and a good deal lighter and smaller/easier to install. Get
yourself an ST150 engine/box.
Treachery and old age will always triumph over youthful enthusiasm.
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monkeyarms
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| posted on 21/8/13 at 01:22 PM |
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Ford 1.4 zetec = 90bhp
Weight = 510kgs
It is brilliant on road as you can use most of it without getting too much into trouble, but needs more power for track use.
Handling is brilliant, even if my road tires melt on track 
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dai1983
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| posted on 21/8/13 at 02:03 PM |
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Cheers guys.
It all hinges on weather I go to Norway early next year or if I want to wait a bit longer to get more money together. Another option that's
caught my mind is the civic type r engine as its just under 200bhp and my last car was an Accord type r. However ver ive been told the k20 engines are
heavier than the zetec se and 15kg more the k series 1.8.
Is the st150 package the pick of the duratecs for a good cost/Bhp/weight/install compromise?
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monkeyarms
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| posted on 21/8/13 at 02:10 PM |
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I am going to go out on a limb here and say no, a st150 isnt the best for cost/bhp/installation. As shown in other builds it needs a different cam
cover £££ and an engine package including ford ECU+loom would be close to £1000. Unless you go aftermarket ECU then that could cost £500 extra to
engine cost.
For me a standard puma 1.7vti engine+ecu package at around £300 and 125bhp is hard to beat, and is very easy to install.
But it depends if you are chasing big power numbers, or have a lower cost easy build.
Just my 2p
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Jenko
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| posted on 21/8/13 at 02:24 PM |
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I think the point David was making was with a duratec, you are basically unlimited in what power you can get (ok, up to 300bhp), but for serious
power, you need to look at the mtx75 gear box as they are stronger than the IB5. The ST150 comes with an IB5 which is around 10 - 15kgs lighter than
the MTX75, so unless you plan to go for big power, and st150 package is actually not a bad option. You are correct about the rocker cover, if you
don't want to the power bulge on the rear clam then a raceline rocker cover is useful....but, they do fit.
Going back to the honda engine.....cracking engine, but as it's an iron block a duratec with throttle bodies is probly going to be the lighter
option.
MY BLOG - http://westfieldv8.blogspot.co.uk/
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monkeyarms
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| posted on 21/8/13 at 02:33 PM |
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I agree if when talking about big power figures a st150 is the best choice, but he did mention cost too. Is the extra 25bhp over a 1.7vti worth the,
possibly extra £1000 cost, worth it?
I just think the puma package is great value for what you get. And is probably my winter upgrade 
whatever the choice, (even an 1.4!) the J15 is a great car to drive, the engine comes down to personal choice.
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Jenko
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| posted on 21/8/13 at 02:59 PM |
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Agree, the puma engine seems to be very good value......
I went down the route of a donor car, of which I was able to use the engine, gearbox, steering column, lots of wire, clips, wheels, gear linkages,
gearstick and knob, fuel pump, emergency cut off switch, sensors, steering wheel (although since changed) plus sold lights and some other bits for
£150. So, that lot effectively cost me £100 as I only paid 250 for the car.
As with any engine, I changed the water pump, cambelt, clutch, oil, etc....but still a cheap option. My hope is to fit it with the FRP camshafts and
an aftermarket ECU, this should get me to around 155bhp (possibly a little more if the engine is nice and healthy).
MY BLOG - http://westfieldv8.blogspot.co.uk/
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deeceee09
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| posted on 21/8/13 at 03:07 PM |
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I must admit cost was not such a factor for me although I did pick up a second hand Duratec complete with said TBs, cams and ECU for a reasonable sum.
Believe it or not it came out of an Elise conversion where it was replaced by a 2.3 li lump. I really did not fancy the K series and to get decent
power from a Sigma was going to be costly. New 2 li Zetecs can be picked up for reasonable sums although quite tunable they are heavy. So horses for
courses I guess.
Treachery and old age will always triumph over youthful enthusiasm.
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dai1983
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| posted on 21/8/13 at 03:29 PM |
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I have actually been offered a 100k mile 1.7 Puma by a collegue for £100. However he does say that there is a problem with the vvt (or whatever Ford
call it) so my guess is its probably been run on the wrong oil, on low oil or a sensor/motor is broke. Pity as this could mean a new/different engine
and a Q plate.
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Jenko
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| posted on 21/8/13 at 03:48 PM |
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If it's the actuator, they are fairly simple to replace, and easy to get hold of......could be worth a punt for 100 quid.
MY BLOG - http://westfieldv8.blogspot.co.uk/
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dai1983
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| posted on 21/8/13 at 04:45 PM |
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Will give him a shout when I get back into work. How do you tell if its nackered?
He bought it as a runner with mot and tax for his mrs. This happened so he's lost all interest. He bought a 1.8 mx5 with a hardtop, stainless
exhaust, aftermarket manifold and a complete set of unfitted poly bushes for a £100 off another collegue.
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dai1983
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| posted on 21/8/13 at 06:11 PM |
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Just spoke to him and he is actually scrapping it tomorrow. He put a code reader on it which said the vct was over retarded. He says the cam belt
needs changing but its not snapped and the engine is turning. Going to get it and even if the engine is knackered then ill just break it and scrap the
shell!
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nickm
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| posted on 22/8/13 at 05:00 PM |
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Hi
I believe Jeremy might have some info on the Honda engine as i believe the fella running a J15 in the 750mc CEC is running a Honda Type R ?
Jeremys demonstrator has a 1.6 MG engine and i believe that weighs 515kg (mag articles etc), im going for sub 500kg (he hopes) with a 1.6 Sigma, we
shall see ?
Its all personal preference i know Jeremy has mentioned that cams can cause vibrations as there is no rubber in the mounts so i will experience the
car before i fit these if at all, but the prisoner has solved that issue.
Enjoy the research is all part of the fun !
Nick M
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dai1983
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| posted on 22/8/13 at 08:17 PM |
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Yeah it is all fun doing research. At the moment I'm trying to find a good cost/weight/power balance. There's a thread on here where
someone has got 150bhp out of a 1.6 sigma with cams, bolts and a remap. Surely not?
Aftermarket cams cause vibrations in the sigma engine? I mention the type r as they are common in Elise conversions. As has been said they are heavier
anyway. My boss has a 1.6xe powered Westfield on carbs which I guess would give performance similar to a tuned sigma or k. I can use this to guage how
say 500kg and 140bhp performs
I bought the puma but I need to investigate. Apparently it broke down and felt like the belt snapped. He towed it home and it gave a "vct inlet
cam retarded" fault code but the belt is intact and the engine still turns by hand. I'm guessing the belt slipped knocking out the timing,
the vct solenoid is gone or the vct system is completely knackered
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nickm
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| posted on 23/8/13 at 07:22 PM |
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Hi
The fella who runs the J15 in the 750mc used to run a 1.6 Sigma in a R1ot at 193bhp, the rr run is on youtube.
Emerald have given me a base map for a 1.6 Sigma which has been ported,cams,tbs and it is rated at 183bhp with no internal changes. Im hoping for
140=150bhp with tbs ?
I use to run a 1.7 Puma it is a brilliant engine pulls like a train at those important speeds 40=70 for road use.
The vibration thing is because Jeremys original design had the engine hanging from the engine mounts with steel to steel fittings with only a bush at
each end of the two hanging mounts it is just one of those things he mentioned to me. I think he has changed the mounting now.
Just a general point it is a lot easier to go down a well worn path than try to be to original ! i am no engineer which is another reason why i chose
the Sigma.
Nick M
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