Chris Byrne Posted December 3, 2003 Share Posted December 3, 2003 I've got a Classic 7 that when purchased (not new) from caterham was described as: 1600 Ford Sprint - Classic 100bhp - Twin 40 webers etc. - over xmas I am debating installing a Piper Camshaft kit (£148) from Demon Tweeks. Is this a silly idea ? how can I tell whats in it at the moment ? I really want extra power in third for that mid range grunt. Cheers Chris. Link to comment Share on other sites More sharing options...
Anthony Posted December 4, 2003 Share Posted December 4, 2003 Hi, no doubt you will be swamped with suggestions, but here goes 1. Suggest 3D mapped ignition will help 2. Cylinder head work might be useful before major cam swaps. Kent 234 has been a sensible upgrade 3. If you are upgrading, weak link has historically been cast pistons, if you are replacing a quick upgrade to 1700/1800 will help 4. 1600 is a great starting point, but very easy to get upgradeitis, best to set a limit and design your whole solution around this Kind regards Anthony Engine in, oil lines in, now where's the hacksaw to cut the secondaries... Link to comment Share on other sites More sharing options...
greg Posted December 4, 2003 Share Posted December 4, 2003 Anthony, ISTR that the 1600 pistons are not that bad...... But Anthony is right that 3D ignition and head work will help the most, and the easiest to do as it does not involve removing the whole engine (which the cam change does) Sig: If it is such a big issue why are the WSCC, Piston Heads, SELOC, BBC, Channel 4 ... not members only? Link to comment Share on other sites More sharing options...
Chris Byrne Posted December 4, 2003 Author Share Posted December 4, 2003 cheers guys - I must confess the thought of not removing the engine does sound very appealing - I will pick Dave Jacksons' 3D mapping Knowledge at the area meeting. thanks chris Link to comment Share on other sites More sharing options...
Anthony Posted December 4, 2003 Share Posted December 4, 2003 Thanks Greg, pistons are weak link if you are going to rev engine above original design range. I like the idea about external mods first though. Has me thinking wishful thoughts about my x-flow now Anthony Engine in, oil lines in, now where's the hacksaw to cut the secondaries... Link to comment Share on other sites More sharing options...
Roger King Posted December 5, 2003 Share Posted December 5, 2003 If you're going to change the cam, you will need to modify the rest of the engine to suit. With your spec of engine, the first thing to do would be to gasflow the cylinder head. There isn't a lot of point in a cam change on a Crossflow without doing this because the porting is poor as standard and won't be able to make full use of the cam. With a mild cam,this might be all that you need to do. If, on the other hand, you opt for a 'bigger' cam, then there is a whole raft of work needing doing, including the forged pistons that others have mentioned. Tuning engines is an art that requires a holistic approach (sorry to sound a bit new age),in that you don't just fit a cam and say it is worth 10bhp, then flow the head and say it is worth another 8bhp, etc. Instead, you need to look at the engine upgrade as a complete package of measures that suit each other and together will be worth say, an extra 25bhp. Or another package of parts that suit each other and give an extra 40bhp. The worst example of the bit by bit approach is when a race cam is fitted to a basically standard engine. These parts do not suit each other at all and you end up with a cam that won't produce any power at low and medium revs, while the rest of the engine won't breathe well enough to allow the cam to produce any power at high revs - result is that you don't have useable power anywhere, and it's horrible to drive too. I do agree with the suggestions for 3D ignition though. This suits engines of almost any spec if mapped properly and will also allow you to run much more advance at high revs than the standard (horrible) distributor that is fitted. You should see both more power and better driveability. Link to comment Share on other sites More sharing options...
Roger King Posted December 5, 2003 Share Posted December 5, 2003 If you're going to change the cam, you will need to modify the rest of the engine to suit. With your spec of engine, the first thing to do would be to gasflow the cylinder head. There isn't a lot of point in a cam change on a Crossflow without doing this because the porting is poor as standard and won't be able to make full use of the cam. With a mild cam,this might be all that you need to do. If, on the other hand, you opt for a 'bigger' cam, then there is a whole raft of work needing doing, including the forged pistons that others have mentioned. Tuning engines is an art that requires a holistic approach (sorry to sound a bit new age),in that you don't just fit a cam and say it is worth 10bhp, then flow the head and say it is worth another 8bhp, etc. Instead, you need to look at the engine upgrade as a complete package of measures that suit each other and together will be worth say, an extra 25bhp. Or another package of parts that suit each other and give an extra 40bhp. The worst example of the bit by bit approach is when a race cam is fitted to a basically standard engine. These parts do not suit each other at all and you end up with a cam that won't produce any power at low and medium revs, while the rest of the engine won't breathe well enough to allow the cam to produce any power at high revs - result is that you don't have useable power anywhere, and it's horrible to drive too. I do agree with the suggestions for 3D ignition though. This suits engines of almost any spec if mapped properly and will also allow you to run much more advance at high revs than the standard (horrible) distributor that is fitted. You should see both more power and better driveability. Link to comment Share on other sites More sharing options...
Sheds Moderator Posted December 5, 2003 Share Posted December 5, 2003 He only needs one cam Roger, it's a Xflow not a K. 😬 Link to comment Share on other sites More sharing options...
Chris Byrne Posted December 5, 2003 Author Share Posted December 5, 2003 Thanks Roger I can hear my old grandad telling me as a kid- "if it ain't broke don't fix it !" Major surgery at the moment is not necessary. 3D mapping really interests me - its sounds a more refined fine way to improve the engines characteristics. When I asked friends about the engine, in hindsight, I guess I got the classic boy racer/rally boffin - "change the cam" answer. I now appreciate that other factors come into play. Anyway shes a beast and I love her !!!! regards Chris Byrne Link to comment Share on other sites More sharing options...
Gavin Posted December 5, 2003 Share Posted December 5, 2003 Chris, I have the same spec. engine. This year I fitted the Weber Alpha 3D kit and it is VERY VERY good . No power gains but the engine really does run so much better. A rolling road session followed to make sure everything was set up. 3D kit is quite easy for DIY fitting. Do you have a competition ( side exit ) exhaust ? A small gain here I think. I plan to have the head gasflowed soon, a gain of perhaps 5-8 BHP. All this of course can be done without having to remove the engine. My car ( 1996 ) has camshaft Ford ' GT ' as fitted to later 1600 sprint engines. Camshaft ' A2 ' was also fitted, I don't know how you can tell which cam is fitted, someone was asking the same question a few months back. Gavin. To Freestyle tommorrow for suspension set up 😬 Edited by - Gavin on 5 Dec 2003 21:42:06 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now