I think it's about time we had a blog update...so... Tony Barber's head upgrade... ...and even Tony hasn't seen this one yet...in it's almost finished form... We've upgraded it from last year's 40.5mm inlet spec with some new 42mm R.E.C valves. Flow has come up from just over .300 thou lift, peaking at 104 cfm @ .550, with 101cfm @ the peak cam lift of just over 500 thou...so a decent increase from the 93cfm the old valve size made. And what's this...a "modern" Mk2 Golf in the JMR workshops mixing it up with all the Mk1's! Well actually, it's the new JMR project car. The plan is to use it as a development mule for some MK2 parts...gearlinkage, mounts, engine parts etc. It wont be a race car but pressed into service as an everyday hack & occasional trackday toy, so mods need to be road usable but help to add to the fun on track...a bit like some of you use your own cars for.. A lot of mods will be from the tried & tested camp, along with some JMR love in the engine department. It'll be staying 8v, and the K-jet is for keeps too...maybe! The basics need a little TLC, but as an early A-reg example it's never going to be mint...but it'll do the job. Jon Wright's Hillclimb MK1 came in for some pre season suspension work and a gearbox change. It was'nt too hard to see why Jon said the front end felt odd ever since he had some new spherical top mounts fitted. As is the norm with these, they fit under the inner wing and reduce the already minimum damper travel of a low running car...in this case to zero! We have some new top mounts under development but they arnt ready yet, so I pressed my old modded Bonrath mounts into service and set up the camber & tracking. Some folk also have an odd take on settings...everyone has been telling Jon to run the car soft, including tyre pressures. On finding 18psi all round and rear spring & damper settings that are far too soft, I put some air back in the tyres and re-set the rear shocks...the springs need changing too but that's for phase 2. Out came the 5-speed box and back in went the 4 speed I've had re-built by my good friend Alvin at A P Motorsport. Alvin is my dyno man and all round good egg and spent his early motortrade years in the warranty department of a Ford dealer re-building gearbox's & axle's on MK3 Cortina's...yep...he's knocking on a bit!...but he know's his way around a gearbox. Jon managed to totally smash 2nd gear to bit's on the first practise run with the then new engine last year so Alvin built one good box from the 2 we had to play with. Running a 4.6 final & an underdriven 1.13 4th from a GTi gearset it'll still pull over 100mph at 8k, so more than enough for the hill's, and many sprints too...it'll rev on past 8000 with no drama when needed, and should be just about maxing out in 4th on a 1/4 mile sprint...oh...is there a 1/4 mile sprint at inters... Well, the above appears to have worked well enough...with Jon's swift wheelmanship, JMR have started the season with a class win at Wiscombe Park Hillclimb. With the revised suspension settings, Jon's feedback is of a much more controlable car, with a lot better feedback (I suspect some air in the tyres now helps!), enough to pull a 3 second advantage over the nearest opposition yesterday...in the wet! Coming soon... 2ltr 8v crossflow development engine... 2ltr 16v ABF rally engine... ...both will be giving the AP Motorsport dyno a good workout in the next few weeks...
Yr welcome...MK1's can still cut it... Err...49.2?....I'm sure that's what he said on the phone yesterday...it was low 49....I'm waiting on the times to do a website update. The dry class record is mid 45's...Jon has done a low 46...46.06 from memory...on the the old engine...we're 20hp up on that with a lot more grunt right through...and a better handling car.
Still good on that power. 49.29 was his wet time at the weekend...the 2nd place Elan (sub 180hp Lotus twincam and very experianced drivers) did a 52.21, and the same car with it's double driver 3rd with a 52.50.
Blog update time... We had a fast road conversion to do recently a Mk1 Cabrio. The the guy wanted something he can go out on a sunny Sunday in with the roof down and enjoy a bit of extra power when desired but without the need to hit the redline everywhere. I figured a conservative approach was needed so ported the head in a different manner to how I normally do them. I kept the valve sizes at the std GTi 40/33, enlarged the throat area slightly less than I would when looking for the best flow from the standard size valves and left both the inlet & exhaust ports totally stock/unported...no smoothing...nothing...just as they come from the factory. The inlet manifold is also standard, as is the throttle body. Despite keeping the ports std, the increased throat bowl size gave just over a 20% flow increase on the inlet side from standard..I also made an interesting discovery with the std hydraulic head flow...more on that at a later date. I had the head skimmed to suit the cam I wanted to use, so brought the chamber size down from the std 30cc to 27cc to give a 10.5:1 C.R. Being a later Cabrio it's a hydraulic DX with K-jet, so I fitted a Newman Phase 2 fast road cam with 268 degree's duration & .420 thou lift & a vernier pulley. Newman had a bit of bad press a couple of years ago with issues of incorrect keyway locations on GTi championship supplied cams etc. But based on the quality & condition of a race cam I removed from an old hillclimb engine, and the quality of the cams I've since bought & the service received, we have become a Newman dealer. The owner fitted the head & cam to the standard 1800 bottom end & timed it up as I recommended as a starting point...or at least I hope he did!,,,along with a modded airbox, Jetex system, and a tubular manifold. The manifold is a short primary...long secondary type...virtually a copy of the std cast manifold & downpipe...so I doubt there's much gain there. And now excuse time!...lol I did'nt get chance to make it to the dyno myself on the warm Saturday morning when the Cabrio turned the rollers, but with conservative ignition timing of 27 degree's running on 95 unleaded, a slightly leaner than ideal mixture right through the rev range of 0.93 and no time to swing the cam timing, the above spec made the power curve below... Peak power, as can be seen, hit 108hp at the wheels @ 5,500rpm, and is hanging on very well at 6K still with 106...cam's of circa 270 degree's normally fall away fast after mid 5's so I suspect the cam timing is'nt ideal for peak power in terms of numbers, but when the whole curve was plotted up, both my dyno man Alvin & the customer elected to leave well alone! For comparison, on these rollers a std 1800 8v GTi makes 86hp at the wheels & around 112-114ib/ft of torque when worked back, and an 1800 KR 16v shows 110-112 at the wheels. With around 130ib/ft now available from 2,500 to 5,500, and a peak of around 133-134ib/ft @ 5000, it goes up the road well enough...the smile on the owners face after returning from a road test was enough to convince my dyno man apparently! As a package, it's mostly hit the target I wanted to achieve...good road manners, no loss of low end power over standard...in fact a bit of a gain, and decent urge up through the rev range when needed. I think peak power can be raised with some cam timing adjustments as both the peak torque & power points are a little high, and the leaner than ideal fuel mixture could unlock another couple of hp going from previous experience...though the owner reported back just over a week after the rollers session to say how pleased he was overall, and fuel consumption...or rather the lack of it... is better than before...with twins about to enter the household the poor chap needs all the help he can get!
Jon Wright had a good run a couple of weekends ago with the yellow peril hillclimb Mk1. Jon's previous best at his local Wiscombe Park hillclimb was a 46.06, and his goal was to break into the 45's....something I was more than confidant he would do with the new engine. He certainly hit his target...45.17...."fornicatingly rapid in a straight line"...apparently! Competition is strong in class A2 down here in the Southwest, so despite knocking almost a second off his previous best, the competition has caught up...Jon's strong run gave him a 3rd in class, with launch control aided Mk2 Escort in 2nd with a 45.04, and a steam roller sized tyre Lotus Elise in 1st with a 44.91. Jon's biggest problem now is putting the power down coming of corners due to damper issues...he feel's it's costing him at least 1/2 a second....watch this space for progress. On the plus side, after 2 rounds, Jon is leading the Wiscombe hillclimb championship.
Nice work there on the cabbie. That would feel strong in any gear at any speed so no wonder he is happy . There looks like there is a bit of a hole in the torques between 2.5k and 5k but as you say it was lean with less than ideal ignition too. Nice result on the Yellow peril too. So with corner grip sorted, he could be in with a chance of a class win still? Gurds
...I'm a director I'll have you know!... Yeah I think a bit of fine tuning could fatten it up with some cam timing/ignition/ tweeks, and a slightly richer mixture...though I think some of the 8v guy's are getting similar peak power from 2ltr's with similar cam specs...though better mid range again....but for an 1800 this one's grunty enough. Thanks Gurds... Jon's hillclimber needs more corner grip and corner exit traction...it's a damper issue caused by too short a shock with my tall/modded top mounts. He's had 2 class wins out of 3 events with the new engine to date...all on less than ideal suspension. We may also look at launch control on his...the opposition feel they need it now!...I'm fairly sure his Emerald has it in the program. With the traction sorted it's on for an easy 44 second run, and there's more I can drag from the engine yet.
That looks like the sort of result that a lot of tuners claim to get from a 1.9 or 2.0 8v, rather than an 1800. Nice work! Hope you manage to get him back for the fine tuning, if the nappy budget allows it!
Thanks Mike ..yeah I hope he's not too knee deep in s.......! lol I used to see a lot of 1900/2ltr conversions from others way back, and most made the same power std KR's were showing on the same rollers....110-112 at the time...with big valve heads & 285 cams, so yeah it's reasonable from a tame 1800, though not the best possible...I feel there's another 4-5 hp locked up in there with some more fuel, a better exhaust manifold & better air temp control, plus a small cam timing tweak.
Uh oh, My hopes are up... Maybe this could stir up some ideas for the O2A. Yes, yes... beating a dead horse. http://www.ebay.de/itm/VW-Golf-1-Sc...&otn=5&po=LVI&ps=63&clkid=9153280930865320388
