You should change to a Zetec and give me first dibs on the crossflow!
Cheers
Jon
Currently my car has a 1660cc X-flow engine that's working really well at the moment. However, if I want more performance I'll have to
spend a heap of money. As many have said on here, I can easily get an increase from the existing < 100BHP to > 130BHP for a fraction of the
money by replacing the x-flow with something like a bog-standard 2 litre Zetec. This would also allow future upgrades such as MegaSquirt.
I was thinking about gathering up the necessary bits & pieces over the summer, ready for an upgrade in the winter. The question is, how much
should I expect to pay, what should I look for, and what else would I need to get before installation? This is to use the engine 'as-is' as
far as possible, until I decide to upgrade it.
Any clues gratefully accepted!
cheers,
David
so glad you asked, i'm thinking the same (and desparately trying not too!)
I bought my son in law a 96 1.8 Mondeo 8 months back -- cost 150 pounds + auction costs --- it went straight through an MOT and has been in daily use ever since without spending anything on it.
what state is your crossflow in?
Is it rebuilt in terms of bottom end?
I know where you are coming from in terms of modifying, but you can have some good cheap fun modifying the crossflow, and learn a lot while doing it,
and stuff like gaskets sets etc are dirt cheap so popping the head on and off a few times won't break the bank.
Not like me to suggest this sort of thing but if I had a crossflow powered car that's what I would consider, a bit of diy porting is very
satisfying, nice to keep the old traditions going as long as you can!
It was fully rebuilt around 1000 miles ago. Unmodified head (apart from port matching) with a BCF2 cam and a Weber down-draft carb. Bottom end is
standard, but with all new bearings, plastigaged etc. so they are a good fit. Standard rod bolts, which I may have to upgrade if I add more power.
The upgrade path I was considering was to get a set of throttle bodies and a manifold from Bogg Bros, together with MegaJolt. I'm not sure I want
to go over to MegaSquirt just yet - undecided.
Trouble is, whichever upgrade I go for is going to cost me £300-ish, for which money I can probably install a 2-litre Zetec and give myself a future
upgrade path from there. The downside of course is that I'd need a new exhaust system, fuel lines & pump, etc. which is all extra cash.
I'm not looking for a heap of screaming power - more torque at lower revs would be good.
These are all the reasons why I'm thinking about it now, while there's plenty of time.
David
I would be seriously tempted to stick with the crossflow!
Zetecs are cheap, but they are generally high mileage and not quite as "bolt-in" as people will have you believe.
Personally I would spend £300 on the crossflow, which with the number of them being torn out and replaced by bike engines and zetecs means tweaky head
parts are really quite cheap now.
You can get a spare head, port it properly, fit big valves, get some 1300 pistons and get them valve pocketted, fit a nice cam and get yourself in the
region of 130 hp for that £300 region if you use good secondhand parts.
No reason not to megasquit and megaspark the crossflow either, would go nicely with bike throttle bodies, think MikeR is doing that.
Much as I am probably regarded on here as a 16v engine type of person, I do like the crossflow, principally because it's light and it, when built
nicely makes fair power and is lovely and torquey and totally reliable.
I wouldn't fancy changing a valve on my XE 16v in a rally service area in under an hour, but we've done it on a crossflow!!!
[Edited on 25/5/06 by NS Dev]
Actually - I've just thought of another possible limitation...
What power will a bog-standard Escort Mk2 live axle take?
David
In a 7, I'm not too sure, Procomp will tell you as he has the experience.
In a Mk 2 escort, we worked on 150hp pinto being the limit, much more seemed to snap halfshafts.
That's roughly what I'd half-remembered hearing previously... and I'm not planning to replace my back axle just for a while!
That makes upgrading the x-flow a more attractive option.
I'd rather avoid the complication of MegaSquirt, so what improvements could I expect with a set of bike carbs? With or without flow work?
I should add that it's already a GT head, so there's not much that can be done with bigger valves, unless I pay for a lot of machining work.
Now we unfortunately get close to my crossflow engine knowledge limit!
Is the GT head chambered? I think you are best starting with a flat head, surely with recut seats you can get bigger valves in fairly easily? (I
don't know though!) seat recutting is cheap enough to get done, bronze guides are worth having and not too pricey to do either.
Do you have 1300 pistons in already, worth a lot of compression which you want.
Careful porting is well worth doing, and if it's a winter project I will hopefully have a diy flowbench by then so may be able to help (have the
porting gear now but no flowbench to check results!!)
GT just had larger valves - although the valves can go a lot larger, the issue is that he head needs porting for it to be any use as there are quite
restrictive in standard form.
thing is - i'm tempted for the ease of getting 130bhp. yeah needs a new fly, water pump, sump, engine mounts, alternator and fuel injection.
If i get the crossflow running on FI - then its not that big a job to convert over .....
The Caterham Supersprint X flow gave about 130bhp, Kent 234 or 244 camshaft ,webers, and they were quick cars.
[Edited on 25/5/06 by Surrey Dave]
i think (and for me) the argument is, its cheaper to get that sort of power from a 2.0 litre zetec than it is from a 1.7 xflow.
Sure!!, but you've got the extra height , which is hard to get under a book locost bonnet line ( I know i've got a 2.0 Zetec sitting in my garage waiting and I've measured) , you need another manifold ( or you could maybe bend the old one and replace the flange), you need Megajolt or you can use an Esc ignition module, some carbs and a manifold , bike carbs are cheap, not easy to do for £300 .
quote:
Originally posted by David Jenkins
Actually - I've just thought of another possible limitation...
What power will a bog-standard Escort Mk2 live axle take?
David
quote:
Originally posted by NS Dev
Now we unfortunately get close to my crossflow engine knowledge limit!
Is the GT head chambered? I think you are best starting with a flat head, surely with recut seats you can get bigger valves in fairly easily? (I don't know though!) seat recutting is cheap enough to get done, bronze guides are worth having and not too pricey to do either.
Do you have 1300 pistons in already, worth a lot of compression which you want.
Careful porting is well worth doing, and if it's a winter project I will hopefully have a diy flowbench by then so may be able to help (have the porting gear now but no flowbench to check results!!)
David,
You should change to a Zetec and give me first dibs on the crossflow!
Cheers
Jon
quote:
Originally posted by David Jenkins
Currently my car has a 1660cc X-flow engine that's working really well at the moment. However, if I want more performance I'll have to spend a heap of money. As many have said on here, I can easily get an increase from the existing < 100BHP to > 130BHP for a fraction of the money by replacing the x-flow with something like a bog-standard 2 litre Zetec. This would also allow future upgrades such as MegaSquirt.
I was thinking about gathering up the necessary bits & pieces over the summer, ready for an upgrade in the winter. The question is, how much should I expect to pay, what should I look for, and what else would I need to get before installation? This is to use the engine 'as-is' as far as possible, until I decide to upgrade it.
Any clues gratefully accepted!
cheers,
David
quote:
Originally posted by jollygreengiant
If he is running 1660cc then I would think that he is using twin cam pistons. If thats the case then deck heighting block is the best option for increased compression. However you should get good power increase from fitting twin 40's or going fuel injection.
Hi David,it seems that over here in South Africa, builders are also looking at the same options(mainly Toyota) however I honestly feel that many are missing the point of a seven, sure most modern options offer more power and are relatively cheap, however the crossflow is still a great package in a seven, it is simplicity itself and when tuned will stick with more modern motors quite easily on "B" roads. A seven's appeal is its handling and agillity, not outright grunt, I am running a crossflow(O.K. so I'm slightly biased!) with a flowed head,1300 pistons, lightend and balanced, 36 DCD downdraft and electronic ignition , it gives me around 120 bhp sure more power would be interesting, but at the mo, the car is superbly balanced and great fun, so my suggestion is stick with the crossflow and as already mentioned keep the tradition alive!
Yes - I like that line of reasoning.
I'm very reluctant to change the engine as it's running well and around 100BHP is actually a load of fun. The x-flow is also a big meccano
set that's really easy to work on.
Decisions, decisions....
David
BTW: Do you realise that we've been discussing engines for a couple of days and NO-ONE has mentioned bike engines yet? Keep quiet, maybe
they're hibernating until the sun comes out...
Xflo was a pretty good unit they were frighteningly quick in clubmans A class of old, more than that it it suits the Seven, much the same can be said
of the Zetec, I think the thing about an Xflo is not to spend crazy ammounts of money on it, don't expect for more than about 120bhp with head
cam and 40s. to get more than that you need a seriously good head and a rabid cam
Personally I think the Zetec looks a better bet but wht do I know I have an Xr3 CVH.
David , I have a ported large valve head converted to use with unleaded for not much more than an unleaded conversion would cost if your interested. Can take to 907s tomorrow if it's still on
Dave,
I'm really keen on my old crossflow too and I'm rebuilding another at the mo.
A nicely done big head can make a significant difference. I don't know whether you'll find the attached head spreadsheet helpful. No
promises I got it it exactly right but I don't think it's far off.
Anyway good luck whatever you do.
Oh, the luxury of choice!
Dave 
[Edited on 26/5/06 by Dave Ashurst]
quote:
Originally posted by David Jenkins
Once again though, I come up against the 'for that money, I'd get the same result with a more modern engine' argument - I'm going round in a circle!
Exactly the same question I'm pondering. Except I'm still running the original unmolested 1300GT engine from my donor (degreased & painted). Starting to blow smoke and getting very tired but little point in rebuilding a 1300. My biggest concern would be that a lot of the modern engines are far too tall to fit under a standard book height bonnet and I don't want to raise it. I'll probably go down the 1600 plus crossflow route because it's easy and I'm not looking for a huge power increase. Plus I think some engine parts are common (head?)