Home

This all started when I needed a cheap car. So I went out and spent £1025 ( in Dec 1998) on a 10 yr old Mk2 astra 1.3. It contained a carburetor fuelled 1298cc 4 cyclinder engine with a nominal power of 75BHP. My version was a Diamond - you got alloy wheels and sports seats, which is nice. Right from the start I thought that it went quite well - quite poky with a top speed of the 110 - 118 mph on the clock which probably means 105 in reality ( wind behind you, down hill. Tested in my private test facility obviously). It was also very reliable (result of my manic maintenance) - 30K in 15 months, no let downs except lumpy running caused by grit in carb. However, after I'd sorted all of the "basics" out I started to want more power.

Dec 1998 Bought for £1025. 85K on clock. Bit rusty in one wing in boot.
Next day Oil + filter, air filter, plugs, leads, thermostat (running cold)
First week Clutch
Next few months Cam belt, steering rack, brake discs, pads, drums, coil, distributor+cap,rocker cover gasket,battery, ball joints,track rod ends, dampers,cv joints (after one failed), handbrake cable (snapped), fuel pump, fuel filter, oil oil oil & engine flush, coolant flush, complete brake bleed, clock light, waxoyl x 3 cans, radio aerial, front calipers (remanufactured units), carb cleanout (lumpy running solved) and probably some other stuff.
77 BHP
April 2000 K&N air filter,Weber carb, Peco big bore 2 exhaust.
84 BHP. Bit better.
May 2000 PMC Supaflow head + Dr Shrick cams
92 BHP (untuned). Much better.Torque steer at last
This doesn't compare too badly with some Nova power figures.
6 June 2000 Still waiting for the exhaust manifold.
Extensive testing of the current set up has confirmed the following
  • It's quite quick from the lights as long as you get the technique right - if the revs don't rise high enough early enough then it's all lost in a swamp of throaty noise. Two seconds later it all picks up. The best results are accompanied by a little bit of tyre squeal.
  • It sounds great.
  • The clutch slips. Once, on a racing start, it never got a proper hold at all. Pulling away up hills makes it apparent as well.
  • Fuel ecomomy isn't too bad - 30-35mpg. I haven't managed to try driving with economy in mind yet.
  • Top speed is up. Since power is proportional to speed squared, you would expect a 20% increase in power to give about a 10% increase in top speed, which it has. (On rolling road up from 103mph originally, to 107 without head&cam, up to 112 now.)
  • My mind has started turning to some of the other deficiencies of the car: ICE, lowering and brakes.
Hopefully, the manifold and rolling road tune will up the top end power to 100BHP ish and give me some more mid range torque.
I've just been out to look at a totally clean 91 reg GTE 8v for £1400. It was a great car no doubt, but some how or other it just didn't turn me on enough. The fun factor seemed a bit lower. I'm sure it's because my expectations were higher. The stealth factor combined with the something for nothing illusion is what makes the current shed good. I did recognise the GTE interior though, since my diamond has the same seats and a few other bits. Oh, and power steering makes a lot of difference - you need to build your arm muscles to wind a standard Astra round a corner.
Conlcusion:I know that the SRi, SXi and GTEs are faster and more powerful, with more modding opportunities, but they also look like they should go faster. I'm better off at the moment following up and using my current project. Unless someone wants the engine for their Nova. Or I find a 16v GTE.Um.
12 June 2000 Just started to price up the next move.
  • A decent GTE 8v could be had for £1500, and a 16v for a bit more. A Peugot 309 GTi or a Citroen ZX Volcane would be the same sort of price,
  • A throttle body kit from SBD would cost £1300+VAT. This would have a start-up ECU program, so that a DIY conversion is OK.
  • A supercharger would cost about £1250, from a company called Eagle One (01278 44507).
  • A nitrous injection kit could be had for about £600 for say 25BHP gain, giving cheap power per pound, but I'm put off by the refilling.
  • A Garrett T2 turbo would cost about £350 - rang round places advertising in back of Autotrader. A Solex sealed carburettor (as used in a Renault 5 turbo) would cost £350. Add a bit and estimate a £1000 ish price for DIY conversion.
  • I've given up on the TurboZet since I'm suspicious about the claims made for it (cost about £390).
  • Somewhere on the web I found an electric supercharger that gave a 5BHP gain. It was operated by a micro-switch on the foot pedal.
  • I'm also thinking about lowering, Cavalier vented brakes, clutch upgrade, and a decent sound system.
Have measured the air temperature at the air filter housing and found it to be in range 30 to 40 DegC. Comparing this with the ambient air temperature of 10 to 20 deg C allows an estimate to be made of the performance gain from a cold air inlet.
Air temp = 10, Filter temp = 40, gain = 5.1%
Air temp = 15, Filter temp = 35, gain = 3.4%
Air temp = 20, Filter temp = 30, gain = 1.6%
So, taking the average figures, there could be 3.4% torque and power gain to be had from using cold air. There's two options in my mind for a cold air duct: 1) Install a bonnet vent 2) fabricate a duct from Aluminium sheet.
17 June 2000

Got the exhaust manifold in at last. It sounds different now - more from front less from rear. It feels a lot slower, must need tuning, probably running weak.

Just spent the afternoon fitting lowering kit (40mm drop) and uprated dampers. A little "grocery buying trip" has shown that there is now a reduction in body roll but otherwise it feels pretty much how it did before...just better. It hasn't transformed the car, just firmed it up a bit, showing that just using uprated dampers is a pretty good move. On the other hand it hasn't ruined it either.

Given up on the Cavalier brake conversion - they mostly use single pot calipers as well. Can't really see any advantage in vented discs since I've never noticed any brake fade (might because I rarely brake). Putting new pads (GM original ones) in has improved the braking considerably.
Backlog of maintenance jobs building up - sump gasket, thermostat, alternator, clutch.

18 June 2000 Refitted the original exhaust manifold - there's no way I could cope with a week and a half of reduced performance until it's rolling road day. Car is lot quiter as a result.

I've been thinking this through and have an action plan.
  • Fit an uprated clutch (this week - I now have days left on this one I reckon).
  • Fit the suspension bushes and brake hoses
  • Get the engine rolling road tuned
  • Play around with cold air ducting - cheap fun.
  • Clean the car properly and polish it a bit
I'll then have a car that's a good bit faster and more responsive than the standard 1.3 and with tighter handling. On a good day it might give a badly maintained 1.8Sri a run for its money. If I tidy it up a bit it'll look OK.
After that I need to save some money and get a life in preparation for project II.Or I might consider an engine swap from a handy 1.8Sri I know of.
19 June 2000

Braided brake hoses fitted, not a fun job. Brakes seem a bit better.

The front end is sinking nicely now. I really noticed the lower when I got in for journey back from work. The door handle is now at the height where the lock used to be.
22 June 2000

Just found the cheapest power gain - a 1.8i 8v engine from GTE complete with fuel tank, gearbox and ancilleries for £80. That should give 115BHP in standard form with 115 LbFt of torque against my current 81LbFt ,a 40% increase.

If I sell all of my current engine nearly new parts for half price then it'll cost nothing. Then I can start tuning up the 1.8.

28 June 2000

Rolling road day. Verdict - exhaust manifold has made things worse not better.

New clutch here and ready. Suspension bushes ready.
2 July 2000 Buy GTE 2L 8v for £1300.
3 July 2000

All good bits removed from the shed for sale. Shed scrapped. Good riddance really.

New car, new history

Home