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Just for a bit of a change in the topic on this discussion I noted the mention of the HT Monaro fitted with 7 or 8" chrome wheels in Geoff's comment and it reminded me of an episode of Torque, done by Peter Wherrett many years back. Did a search on Google - "Peter Wherrett HT Monaro torque" and found a utube clip of that episode which shows what seems to be the same car. Think he mixed up engine size in the commentry. Worth a look though
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Originally Posted by: gm5735  The car Castellan is referring to is KNK777, the ex Spencer Martin HDT car that caught fire at Sandown in 1969. It was fitted with 7 or 8" chromed steel wheels when that test was done, and being ex HDT would not be representative of a standard HT 81837.
The 350 engines for HDT were chosen by testing a container load on the GMH engine dyno. The best ones went to HDT. They were quite consistent, but the best of them were around 260hp.
The best times I ever saw, with a dead stock HT350, with 85,000 miles, 205/70 NCT tyres, super fuel, good grippy asphalt, shifting at around 5,200RPM and a timing spoon under the front wheel was a fairly consistent 14.94 at 147. And I have the event slips to prove it. Dr Terry would know more about 1/4 times than any of us, but my understanding is ET is mostly a measure of traction and technique, but trap speed is a better indication of actual horsepower. The HDT engines run at Bathurst 1969 were actually sent over from the Flint engine plant in the USA, that is why they had 186 cast heads rather than 041. We even have original rego documentation for them that show the Flint engine numbers. That 14.94 is about what i'd expect, given the extra small amount of power out of the later HG engines those were good for about 14.75-14.8s at 95mph. The best I could ever find for the PhaseIII as an original not modified car running steel wheels is 14.7s but no trap speed from Wheels October 1971. The 0-100mph comparison hass the HG at 15.95s and the PhaseIII at 15.2s. Totally agree that mph at the end of the 1/4 is more important, you'd probably expect 96-ishmph from the PhaseIII given the above figures. Mel Nichols HG GTS350 test was Wheels December 1970. Peter Robinson's confirmation was in June 1971 Wheels. |
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Gerard, yes that's the same car. From the footage and the location it looks like the same day that Tuckey had his drive. That car is back in Victoria, and has been restored in its HDT colours from 1969. I'll dig up some photos if you're interested. Poor Peter seems to very confused about years, engine capacities and several other facts. That, and the LSD in his XW just ain't making it. (I've heard it only took a few laps at Bathurst to destroy the HO LSD action...) Byron, The info I got regarding engine selection was supposedly from our mutual unimpeachable source, although I didn't get it directly. I'm aware that some HT350s had 618 blocks, although the norm was the 388 block with 041 heads. Are these the Flint engines you are referring to? Edited by user Wednesday, 17 February 2016 7:32:17 PM(UTC)
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Quote:That 14.94 is about what i'd expect, given the extra small amount of power out of the later HG engines those were good for about 14.75-14.8s at 95mph.
The best I could ever find for the PhaseIII as an original not modified car running steel wheels is 14.7s but no trap speed from Wheels October 1971. The 0-100mph comparison has the HG at 15.95s and the PhaseIII at 15.2s.
Totally agree that mph at the end of the 1/4 is more important, you'd probably expect 96-ishmph from the PhaseIII given the above figures.
Mel Nichols HG GTS350 test was Wheels December 1970. Peter Robinson's confirmation was in June 1971 Wheels.
What's interesting about all of this, given the story that the test cars were nobbled, and if we accept that trap speed is a reliable indication of horsepower, is the Wheels road test of the HT350, NSW registration APX415 in the November 1969 issue. The acceleration graph on page 77 shows the standing quarter in 15.8, at a speed of about 91 mph. About the same trap speed as me, but nearly a second slower. On that basis, the engines weren't nobbled at all. Sorry to swim against the tide of popular opinion, but I think the 1/4 times of the day have more to do with the tires and traction than with any engine nobbling conspiracy.
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What is the truth here?
When I spoke to Harry 20 years ago, he denied the existence of the 186 heads, until I quoted the bulletin. There was no need for him to continue to "cover up" this stuff but they have.
There are so many contradicting stories coming out of Holden and Ford about the cars of this era, that there must have been different stories for different people. To the point now that we may never know the truth.
As just stated, the new tyres give much better grip, so even if you found a low mileage, never touched car, you could not rely n the times generated.
One thing is for sure, neither side wanted the other to know exactly what they had, but to nobble a car to not show the opposition is just a silly theory, as they would buy each others cars to evaluate. Bob Watson ran an XT GT around Lang Lang for a fair period to see what it would do. There is also a great shot of an LC GTR at Chrysler head quarters.
The only reason to nobble a car was to not alert the public as to the true performance.
As for motor sport ban, Holden was heavily involved in rallies prior to the HK. Their focus was on durability on country/dirt roads rather than a bitumen road race, which makes sense when you consider the roads of the time.
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Geoff, I would be interested in seeing photos of this car as it is now. One thing that I remember about this car when I saw it on the original episode was how "un" 350 HT Monaro it looked, other than the bonnet. Overall it looked like a Monaro version of the "white hot special" Kingswoods. Think the original episode about these cars may have been longer than the tube clip?
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Originally Posted by: gm5735 Gerard, yes that's the same car. From the footage and the location it looks like the same day that Tuckey had his drive.
That car is back in Victoria, and has been restored in its HDT colours from 1969.
I'll dig up some photos if you're interested.
Poor Peter seems to very confused about years, engine capacities and several other facts. That, and the LSD in his XW just ain't making it.
(I've heard it only took a few laps at Bathurst to destroy the HO LSD action...)
Byron,
The info I got regarding engine selection was supposedly from our mutual unimpeachable source, although I didn't get it directly.
I'm aware that some HT350s had 618 blocks, although the norm was the 388 block with 041 heads. Are these the Flint engines you are referring to? HDT picking production engines possibly is how it worked for the earlier stuff pre Bathurst 1969, but the engines used at Bathurst 1969 were build for HDT by GM USA and they were Flint supplied hence the different casting numbers. The 186 heads appearing in the bulletin would simply be Harry's way of ensuring that there would be no hassles come Bathurst. It becomes even more obvious that this is what was done when you see the 186 cast head appearing in the bulletin as a casting number not its proper part number which should be the same as the 041 heads. |
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Originally Posted by: gm5735 Quote:That 14.94 is about what i'd expect, given the extra small amount of power out of the later HG engines those were good for about 14.75-14.8s at 95mph.
The best I could ever find for the PhaseIII as an original not modified car running steel wheels is 14.7s but no trap speed from Wheels October 1971. The 0-100mph comparison has the HG at 15.95s and the PhaseIII at 15.2s.
Totally agree that mph at the end of the 1/4 is more important, you'd probably expect 96-ishmph from the PhaseIII given the above figures.
Mel Nichols HG GTS350 test was Wheels December 1970. Peter Robinson's confirmation was in June 1971 Wheels.
What's interesting about all of this, given the story that the test cars were nobbled, and if we accept that trap speed is a reliable indication of horsepower, is the Wheels road test of the HT350, NSW registration APX415 in the November 1969 issue. The acceleration graph on page 77 shows the standing quarter in 15.8, at a speed of about 91 mph. About the same trap speed as me, but nearly a second slower. On that basis, the engines weren't nobbled at all. Sorry to swim against the tide of popular opinion, but I think the 1/4 times of the day have more to do with the tires and traction than with any engine nobbling conspiracy. 91mph is obviously not the engine developing its full power as a HK GTS327 in proper tune did 15.4s @ 92mph in Rob Lucks hands in the September issue of RCN, he also recorded 150 rear wheel hp, and 19.8s 0-100mph, top speed of 128.5mph. This private car had a 3.36:1 rear axle. Dave Bennett backed this up with his own car prior to any modifications doing 15.6s @89mph, 0-100mph in 20.8s and 167hp at the treads, slightly slower as this was a 3.08:1 example. Top speed was 122.3 at 5500rpm (Rob Luck ran his test car to over 6000rpm in top gear). The HQ tests also show the fiddling with the manual car, same engines, same diff ratios, same exhaust yet the manual was over 3 seconds slower 0-100mph. This was on multiple cars, not the same car. The final proof is what Mel Nichols and Peter Robinson discovered later in Wheels on cars in proper tune. Edited by user Thursday, 18 February 2016 6:10:43 AM(UTC)
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Originally Posted by: HK1837 Originally Posted by: castellan Post 91 I think it may be number one of Street Machine, but I got that out of my note book.
Post 92 I believe that the block tooling is amortized at around making 36000 but the HP casting could easy be changed.
Post 93 Wheels did that so as not to be the same as Motor in them days I think.
Did the LX 5.0L SS have 13in wheels ?
I have a LX A9X and a 350 HT GTS test by Bill Tuckey in Apr 1978.
0- 50 KM/H in 3.5 A9X and GTS 350 is 2.9
0- 70 = 4.8 and GTS 4.6
0- 90 = 7.0 and 6.7
0- 110 = 9.8 and 9.3
0- 130 = 13.8 and 12.4
0- 160 = 24.0 and 19.0
400m 15.8 and 15.6 for the GTS
A9X 1st @ 5500 = 97KM/H and the GTS is 77KM/H at 5500
2ed = 135 KM/H and 116 GTS
3rd = 179 and 148
A9X top was 206KM/H @ 4600 and the GTS was 201KM/H @ 5500
A9X had a 2.60 ration diff I would think and the HT GTS a 3.36 ratio. Is Bill Tuckey's figures on the HT a "test" or is it re-hashing original road tests? Reason I ask is those figures look an awful lot like the figures published back when the cars were new, with the secondaries played with on the GTS350 plus the staffer in the car not letting them rev the engine past 5500rpm. The true potential of the car with published figures can only be found in AMC where they run it to peak power and acceleration test the car identically to how they were done in the late 60's and 70's. Mel Nichol's didn't get proper test results as he only had the car for a road test one week and was to do performance figures a week later. He got the car back a week later and it had been hobbled - he only recorded similar figures to what Bill Tuckey has quoted above. Robbo got a HG later and was blown away by the performance of the car. You can see the basics of what they said in Wheels in Joe Kenwright's article I put a link up to in post 80, right at the bottom of the text. I'll see if I can find the actual Wheels editions. GMH definitely introduced new patterns for 308 and 253 and used them alongside the old patterns for a while. We have recorded blank (253) and HP (308) way after 253 and 308 castings appeared. They obviously just used the old patterns until they were unserviceable. The blank and HP also show you how far back they were working on the Holden V8. This usage of blank and HP is EH era, and they probably didn't change them even up until production as the engine sizes weren't finalised until late in the piece. Obviously the sides of the pattern didn't change much and there was no need to change the sides of the patterns until they needed new patterns for volume 308 production - remember 308 engines would only be a trickle of production after initial HT Brougham production until later in 1969. From memory 253 appears earlier than HP changes to 308. Street Machine hot Holdens number 1 is where I got that test from page 9 to 13 it was at Oran Park april 1978 that the test was done.
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Originally Posted by: gm5735 The car Castellan is referring to is KNK777, the ex Spencer Martin HDT car that caught fire at Sandown in 1969. It was fitted with 7 or 8" chromed steel wheels when that test was done, and being ex HDT would not be representative of a standard HT 81837.
The 350 engines for HDT were chosen by testing a container load on the GMH engine dyno. The best ones went to HDT. They were quite consistent, but the best of them were around 260hp.
The best times I ever saw, with a dead stock HT350, with 85,000 miles, 205/70 NCT tyres, super fuel, good grippy asphalt, shifting at around 5,200RPM and a timing spoon under the front wheel was a fairly consistent 14.94 at 147. And I have the event slips to prove it. Dr Terry would know more about 1/4 times than any of us, but my understanding is ET is mostly a measure of traction and technique, but trap speed is a better indication of actual horsepower. Yes that's correct vic KNK777 and the Torana is nsw JNO652. There is no point of going past 5200RPM with the 350. I would change from 1st at 4500 and then go into 2ed to 4500 and then maybe 5200 to get the best times out of it. but most people think that if you have too rev it all the way out like a 4cyl is the go because they are wood ducks, a 350 has Torque !! one should use it.
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Originally Posted by: Dr Terry Originally Posted by: gm5735 but my understanding is ET is mostly a measure of traction and technique, but trap speed is a better indication of actual horsepower. The best quote so far in this topic !! Some very accurate HP figures can be gleaned purely from 1/4 trap speeds. ET numbers on the other hand can vary radically depending on chassis set-up, track condition, driver skill, tyres & traction etc. The Moroso power calculator for example simply uses vehicle weight & MPH figures. Dr Terry Horsepower is only a value that represents a part of the picture and Torque is another and then it's that the rev range that's being used comes into it and all the rest. I am not a fan of people talking about max HP much at all, I like graph then I can work out the gearing ratios of the box and diff as well as the weight etc so I am better prepared for what's best to race with. A wood duck only talks about max HP as if it's the be all. A person may come up to me and say correctly that his car that is just like mine has 350HP correctly true and all and he has the same gearing as well, now should I fear this because I only have 330HP ? no I don't because I have the power over his where it counts. To mention gross HP to me is insane, because it's got nothing to do with reality. If I was building race cars for a team I would not be talking Gross HP and such a person would be shown the back door directly if they did, because we are not going to have any advantage with nonsense like that. Edited by user Thursday, 18 February 2016 11:36:48 AM(UTC)
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Originally Posted by: HK1837 Originally Posted by: gm5735 The car Castellan is referring to is KNK777, the ex Spencer Martin HDT car that caught fire at Sandown in 1969. It was fitted with 7 or 8" chromed steel wheels when that test was done, and being ex HDT would not be representative of a standard HT 81837.
The 350 engines for HDT were chosen by testing a container load on the GMH engine dyno. The best ones went to HDT. They were quite consistent, but the best of them were around 260hp.
The best times I ever saw, with a dead stock HT350, with 85,000 miles, 205/70 NCT tyres, super fuel, good grippy asphalt, shifting at around 5,200RPM and a timing spoon under the front wheel was a fairly consistent 14.94 at 147. And I have the event slips to prove it. Dr Terry would know more about 1/4 times than any of us, but my understanding is ET is mostly a measure of traction and technique, but trap speed is a better indication of actual horsepower. The HDT engines run at Bathurst 1969 were actually sent over from the Flint engine plant in the USA, that is why they had 186 cast heads rather than 041. We even have original rego documentation for them that show the Flint engine numbers. That 14.94 is about what i'd expect, given the extra small amount of power out of the later HG engines those were good for about 14.75-14.8s at 95mph. The best I could ever find for the PhaseIII as an original not modified car running steel wheels is 14.7s but no trap speed from Wheels October 1971. The 0-100mph comparison hass the HG at 15.95s and the PhaseIII at 15.2s. Totally agree that mph at the end of the 1/4 is more important, you'd probably expect 96-ishmph from the PhaseIII given the above figures. Mel Nichols HG GTS350 test was Wheels December 1970. Peter Robinson's confirmation was in June 1971 Wheels. I had a stock HQ 308 engine and I dragged a 350 with a 400 crank that was bombed up, over the 400m and you know I won the race  , but by 405m he flew past me at maybe 80KM/H faster. 1/4 Mile is rubbish that is idolised as the be all, well it's not try 1000m and one gets a much better picture of reality. Edited by user Thursday, 18 February 2016 11:18:03 AM(UTC)
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Originally Posted by: HK1837 Originally Posted by: gm5735 Quote:That 14.94 is about what i'd expect, given the extra small amount of power out of the later HG engines those were good for about 14.75-14.8s at 95mph.
The best I could ever find for the PhaseIII as an original not modified car running steel wheels is 14.7s but no trap speed from Wheels October 1971. The 0-100mph comparison has the HG at 15.95s and the PhaseIII at 15.2s.
Totally agree that mph at the end of the 1/4 is more important, you'd probably expect 96-ishmph from the PhaseIII given the above figures.
Mel Nichols HG GTS350 test was Wheels December 1970. Peter Robinson's confirmation was in June 1971 Wheels.
What's interesting about all of this, given the story that the test cars were nobbled, and if we accept that trap speed is a reliable indication of horsepower, is the Wheels road test of the HT350, NSW registration APX415 in the November 1969 issue. The acceleration graph on page 77 shows the standing quarter in 15.8, at a speed of about 91 mph. About the same trap speed as me, but nearly a second slower. On that basis, the engines weren't nobbled at all. Sorry to swim against the tide of popular opinion, but I think the 1/4 times of the day have more to do with the tires and traction than with any engine nobbling conspiracy. 91mph is obviously not the engine developing its full power as a HK GTS327 in proper tune did 15.4s @ 92mph in Rob Lucks hands in the September issue of RCN, he also recorded 150 rear wheel hp, and 19.8s 0-100mph, top speed of 128.5mph. This private car had a 3.36:1 rear axle. Dave Bennett backed this up with his own car prior to any modifications doing 15.6s @89mph, 0-100mph in 20.8s and 167hp at the treads, slightly slower as this was a 3.08:1 example. Top speed was 122.3 at 5500rpm (Rob Luck ran his test car to over 6000rpm in top gear). The HQ tests also show the fiddling with the manual car, same engines, same diff ratios, same exhaust yet the manual was over 3 seconds slower 0-100mph. This was on multiple cars, not the same car. The final proof is what Mel Nichols and Peter Robinson discovered later in Wheels on cars in proper tune. What one has to remember it that wheels and motor test are given as an average with two people in the car and in both directions etc as well. Rod Luck 6000RPM with a 3.08 diff story can not be correct, it maybe the tacho reading 6000 but not corrected.
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Originally Posted by: castellan Originally Posted by: HK1837 Originally Posted by: gm5735 Quote:That 14.94 is about what i'd expect, given the extra small amount of power out of the later HG engines those were good for about 14.75-14.8s at 95mph.
The best I could ever find for the PhaseIII as an original not modified car running steel wheels is 14.7s but no trap speed from Wheels October 1971. The 0-100mph comparison has the HG at 15.95s and the PhaseIII at 15.2s.
Totally agree that mph at the end of the 1/4 is more important, you'd probably expect 96-ishmph from the PhaseIII given the above figures.
Mel Nichols HG GTS350 test was Wheels December 1970. Peter Robinson's confirmation was in June 1971 Wheels.
What's interesting about all of this, given the story that the test cars were nobbled, and if we accept that trap speed is a reliable indication of horsepower, is the Wheels road test of the HT350, NSW registration APX415 in the November 1969 issue. The acceleration graph on page 77 shows the standing quarter in 15.8, at a speed of about 91 mph. About the same trap speed as me, but nearly a second slower. On that basis, the engines weren't nobbled at all. Sorry to swim against the tide of popular opinion, but I think the 1/4 times of the day have more to do with the tires and traction than with any engine nobbling conspiracy. 91mph is obviously not the engine developing its full power as a HK GTS327 in proper tune did 15.4s @ 92mph in Rob Lucks hands in the September issue of RCN, he also recorded 150 rear wheel hp, and 19.8s 0-100mph, top speed of 128.5mph. This private car had a 3.36:1 rear axle. Dave Bennett backed this up with his own car prior to any modifications doing 15.6s @89mph, 0-100mph in 20.8s and 167hp at the treads, slightly slower as this was a 3.08:1 example. Top speed was 122.3 at 5500rpm (Rob Luck ran his test car to over 6000rpm in top gear). The HQ tests also show the fiddling with the manual car, same engines, same diff ratios, same exhaust yet the manual was over 3 seconds slower 0-100mph. This was on multiple cars, not the same car. The final proof is what Mel Nichols and Peter Robinson discovered later in Wheels on cars in proper tune. What one has to remember it that wheels and motor test are given as an average with two people in the car and in both directions etc as well. Rod Luck 6000RPM with a 3.08 diff story can not be correct, it maybe the tacho reading 6000 but not corrected. Agree. This is why when AMC tested the Survivor HG GTS350 with less than 40,000kM on it they tuned the car properly to factory specs on the carby and the distributor, filled the tank to full (113 litres), used a proper hot mix bitumen road surface, had two people in the car and used lift-throttle shifts rather than flat shifting. The car even had Dunlop Aquajets on it. That is right as it was a 3.36:1 car, Dave Bennetts was a 3.08 until he changed it. Rob Luck showed that the car had a useable rev range exceeding 6000rpm in top gear, whereas at the release the journalists were made to stay below 5500rpm and never given the opportunity to run the car to maximum in top gear. This is why Des West was so fast at 1968 Bathurst, he had a 3.36 rear end and all the others except for one HDRT car were 3.08. Edited by user Thursday, 18 February 2016 4:16:23 PM(UTC)
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Quote: Dave Bennett backed this up with his own car prior to any modifications doing 15.6s @89mph, 0-100mph in 20.8s and 167hp at the treads, slightly slower as this was a 3.08:1 example. Top speed was 122.3 at 5500rpm Have I taken something here out of order or context? 3.08 diff + 5500RPM does not equal 122.3 mph with standard D70/14 tyres and wheels. (Unless there was clutch slip or wheelspin....)
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Quote:Horsepower is only a value that represents a part of the picture and Torque is another and then it's that the rev range that's being used comes into it and all the rest.
They aren't "part of the picture". Horsepower is the mathematical product of torque multiplied by rotational speed. They are not independent variables, and are inextricably linked! Quote:I am not a fan of people talking about max HP much at all, I like graph then I can work out the gearing ratios of the box and diff as well as the weight etc so I am better prepared for what's best to race with.
Much more betterer. (that was deliberate, Terry). What I want is a big fat torque curve, as it is the area under the torque vs RPM graph that we care about if we want to go fast. Peak horsepower and 1 second dyno pulls make for good YouTube videos for the uninformed and not much else, unless you wish to run a stationary engine or have a 15 speed gearbox.
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Originally Posted by: gm5735 Quote: Dave Bennett backed this up with his own car prior to any modifications doing 15.6s @89mph, 0-100mph in 20.8s and 167hp at the treads, slightly slower as this was a 3.08:1 example. Top speed was 122.3 at 5500rpm Have I taken something here out of order or context? 3.08 diff + 5500RPM does not equal 122.3 mph with standard D70/14 tyres and wheels. (Unless there was clutch slip or wheelspin....) I agree but that is what was reported in Australian Motor 12/68. 5500rpm with 3.08:1 rear axle is close to 130mph, as is 6000rpm with a 3.36 rear axle if you use the tyre manufacturer's data of 25.4" diameter for a D70. GMH's Engineering data is 11.99" loaded radius for the D70, 6.27794 feet circumference. They also publish 21.2mph for 3.36 and 23.2mph for 3.08 which if you use their tyre quoted data is not correct - I get 127.4mph for 3.08 rear axle using 6.27794 feet circumference. All I can say is Dave Bennett's car's tacho wasn't reading right - the mph figure they quote is corrected as they calibrated the speedo prior to tests and corrected it in the quoted results. Des West reported getting close to 6500rpm in top gear on Conrod in 1968 and was reportedly doing close to 135mph (3.36 rear axle) but this was on Michelin XAS tyres which are radials, a slightly different diameter and don't grow like a crossply does (GMH quote their tyre diameter figures for crossplys as only good to 130mph). Edited by user Friday, 19 February 2016 8:36:52 AM(UTC)
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Unfortunately there are plenty of numbers to choose from.
The HT Shop manual supplement tabulates RPM/MPH data for different differential ratios and tyre sizes. For D70 they are:
3.08 - 43.17 RPM/MPH. Which gives 5500/43.17= 127.4 MPH
3.36 - 47.10 RPM/MPH. Which gives 5500/47.10= 116.77 MPH.
It also provides loaded revolutions per 1 mile. For D70 it is 824. In the same table are the numbers you mention above.
Unfortunately these numbers do not agree!
824 revolutions per mile, and 5280 feet per mile implies 5280/824 = 6.4078 rolling circumference, and not the 6.27794 quoted.
If you use 824 revolutions per mile you get:
For 3.08, (5500/3.08) x (1/824) = 2.1671 miles per minute. 2.1671 x 60 = 130.03 MPH
For 3.36, (5500/3.36) x (1/824) = 1.9865 miles per minute. 1.9865 x 60 = 119.19 MPH
For the quoted rolling radius and circumference you get:
For 3.08, (5500/3.08) x 6.27794 = 11,210.6 feet per minute. (11,210.6/5280) x 60 = 127.4 MPH
For 3.36, (5500/3.36) x 6.27794 = 10,276.4 feet per minute. (10,276.4/5280 x 60 = 116.77 MPH.
Which agrees with your numbers, the published RPM/MPH figures and shows a discrepancy.
I don't know which is correct, but perhaps one is a dynamic measurement and one a static measurement. I'm tempted to believe the 824 revolutions/mile number, as it is obviously not derived from the static loaded radius, and reflects a tyre expanding at road speed.
What I do know is that anyone spending very much time looking at a HK Tacho at 130MPH isn't going to be around for long, hence I regard some of these RPM figures as being very dubious.
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I agree, the discrepancy is interesting. The tests were done with two people in the car too, so maybe the second bloke viewed them? Hard to say.
GMH's quoted data for the HK shows 21.2mph/1000rpm for the 3.36 and 23.2mph/1000rpm for the 3.08. If you multiply these both by 5.5 you get:
116.6mph (3.36) and
127.6mph (3.08).
So there is another set of data that I guess you'd say is within the limits of error the same as those you put up for the HT shop manual data and the quoted radius and circumference data.
The 824 loaded revs per mile is interesting, not sure what it means as if you use the 11.99" loaded radius or 6.27794 feet loaded circumference and divide 5280 (feet in a mile) by 6.27794 you get 841 revs per mile.
I'm wondering if the 824 revs per mile are for Aquajets or Michelin XAS and an error? Will look closer. I have also found the HK and HT features manuals, but don't have my hands on them as yet. If they are like the HJ-HZ ones they should list the data for optional tyres which will be interesting. |
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Quote:91mph is obviously not the engine developing its full power as a HK GTS327 in proper tune did 15.4s @ 92mph in Rob Lucks hands in the September issue of RCN I beg to differ Byron. From the speeds in gears, APX415 had a 3.08 differential ratio when tested by Wheels in the November 1969 issue. A 91 MPH trap speed is consistent with a known healthy 350, and the ET is consistent with a 3.08 diff ratio.
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