Page 94 of 101
Re: Project 2.
Posted: Thu Feb 15, 2024 7:15 pm
by Brett027
It's what Eddie Wood's Head Stud Developments people call their "Fully Six". They did the calcs using my piston to block top measure to skim it so I end up with 10:1 compression. I think they were aiming for 42cc per chamber. It's a 173 head.
The original head has also been ported, inlets opened up and larger valves, double springs etc.
I remember in my youth we were swapping heads without thinking about much at all. How high tech everything has become.
Re: Project 2.
Posted: Thu Feb 15, 2024 7:47 pm
by Errol62
Thanks Brett. I'm going a similar path with the small chamber and 10:1 comp. Do you recall the deck height you measured, and what thickness gasket you will use?
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Re: Project 2.
Posted: Thu Feb 15, 2024 8:04 pm
by Brett027
Clay, distance was 0.93mm. I will seek HSDs advice on which gasket to use.
And a slight correction: chamber volume is 43cc not 42 as I posted.
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Re: Project 2.
Posted: Thu Feb 15, 2024 10:55 pm
by Errol62
Thanks Brett. That is near enough to same as mine . I measured 0.9 or 0.035”. I’m using an ordinary Permaseal gasket, which should compress to about 0.035” for a total squish height of 0.07”, which some are saying a bit large and may lead to detonation. Hence I will be paying careful attention to timing. Interested to see what gasket they recommend.
FB ute fixer upper, EK van on rotisserie
Re: Project 2.
Posted: Mon Feb 19, 2024 3:59 pm
by Brett027
Mucking around today with pedal box. Converting from cable clutch back to original hydraulic. The cable worked very well until cable sheath seperated from mounting point! Smooth action and good feel. Got a much better heavy duty cable from Dellows to replace the cheap one I had but now not needed). Thanks to Harv I have the bits I need.
Wondering if anyone is using original clutch setup without the big counterbalance spring and if so, how did it go?
Re: Project 2.
Posted: Mon Feb 19, 2024 7:08 pm
by Blacky
Brett027 wrote: ↑Mon Feb 19, 2024 3:59 pm
Wondering if anyone is using original clutch setup without the big counterbalance spring and if so, how did it go?
The spring in my ute broke a month or so ago, I went up the back , found one - refer to previous conversation regarding tripping over a pedal box in the shed - cleaned it up and painted it , went to fit it and had the usual battle , thought fk it I wont bother and its been fine so far, only difference is the pedal is a bit lighter and it doesn't squeak - hard to find a negative really.
Re: Project 2.
Posted: Mon Feb 19, 2024 7:16 pm
by Errol62
I've got the spring, with 5/8" master. Seems good, however it is a funky setup, the spring. Not much help sorry. Are you using a concentric slave Brett?
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Re: Project 2.
Posted: Mon Feb 19, 2024 7:33 pm
by Brett027
I might be- if I knew what that is
![😀](//cdn.jsdelivr.net/gh/twitter/twemoji@latest/assets/svg/1f600.svg)
Re: Project 2.
Posted: Mon Feb 19, 2024 7:40 pm
by Brett027
Blacky wrote: ↑Mon Feb 19, 2024 7:08 pm
Brett027 wrote: ↑Mon Feb 19, 2024 3:59 pm
Wondering if anyone is using original clutch setup without the big counterbalance spring and if so, how did it go?
The spring in my ute broke a month or so ago, I went up the back , found one - refer to previous conversation regarding tripping over a pedal box in the shed - cleaned it up and painted it , went to fit it and had the usual battle , thought fk it I wont bother and its been fine so far, only difference is the pedal is a bit lighter and it doesn't squeak - hard to find a negative really.
Thanks Blacky. I remember from Wilma that the spring is a difficult thing to fit- a vice and vicegrips were in play from memory. I'm only wondering about it because my Torrie column breakaway bolts mounts required a few mods where the spring prong/thingy was, so it would be a bit less work not to put it back. Will see if anyone else pipes up about it in the next 24 hours.
Off to Hardy Spicer tomorrow for same-day driveshaft shortening and balance. Looking forward to seeing how they do it.
Re: Project 2.
Posted: Mon Feb 19, 2024 8:03 pm
by Brett027
Errol62 wrote: ↑Thu Feb 15, 2024 7:47 pm
Thanks Brett. I'm going a similar path with the small chamber and 10:1 comp. Do you recall the deck height you measured, and what thickness gasket you will use?
!Sent from my SM-G781B using Tapatalk
HSD peeps just said to use a standard off the shelf head gasket Clay. Also suggested NGK BP7FS plugs.
Re: Project 2.
Posted: Mon Feb 19, 2024 8:34 pm
by Errol62
Thanks Brett. I’ve always used NGK . They were recommended when I was running a car on LPG. Concentric slave per the Mal Wood set-up. I thought you said you had one when I was taking a shim out of mine.
FB ute fixer upper, EK van on rotisserie
Re: Project 2.
Posted: Mon Feb 19, 2024 9:14 pm
by Brett027
Ah- yes I do. Had one on hand for the M20 and recently swapped it over for one that works on Celica W50 box. I haven't decided yet to go EK original slave and master and red throwout lever (which I know works reliably) , or go &*#@ master and Mal's thingo. Need to talk to him about a few things, including but not limited to, the need for a clutch pedal stop.
Re: Project 2.
Posted: Mon Feb 19, 2024 10:16 pm
by Errol62
It is a definite improvement on the 3 speed in my ute over the stock slave and rat trap clutch fork.
FB ute fixer upper, EK van on rotisserie
Re: Project 2.
Posted: Tue Feb 20, 2024 9:57 pm
by Brett027
Dropped my driveshaft off with Hardy Spicer at Unundara this morning. There were very accomodating and had it shortened, new yoke for W50 installed and balanced and painted in 3 hours. A total of $330 for the work and the new end billet that is required for the new weld. Shaft was perfectly straight after all those years. The fellow ( David) suggested that I use unis with nylon end washers inside the caps as they are better wearing. I didnt know that there was such a thing. He also doesn't like unis with grease nipples, as he reckons the seals are better on non- greasable ones.
We then went on to discuss rpm and driveshaft deformation at overspeed. For my 2.5inch diameter shaft, the maximum rpm it can spin before it starts to flex is 4908rpm. In top gear at 1:1 ratio, this is only 4908 engine rpm. The trouble is with overdrives where the shaft speed is higher than the engine speed. For my Celica 5 speed the engine speed reduces 15% in 5th gear (1:0.85) so maximum shaft/engine speed is about 4300 rpm in 5th. This is all much faster than my engine will provide (100km/hour with my 185 80 13 tyres and my 3.36:1 diff is about engine 2600 rpm), but with fancy donks the limitation of a standard diameter driveshaft might be an issue. Apparently this is one of the reasons for shorter split shaft setups. A larger diameter shaft allows for higher rpm. I had to sign a disclaimer that had the maximum shaft rpm listed.
Overall an interesting but long day.
Re: Project 2.
Posted: Tue Feb 20, 2024 10:11 pm
by Errol62
Good argument also for a tall diff and or big tyres over overdrive. It’s 40 years since I had a tailshaft shortened and balanced. I hoped the overdrive would improve the 22mpg I was getting out of my 202 HX van on the highway. It made no difference at all to the economy. Would have been a 3.36 diff I assume, with 225/65 R14 tyres.
FB ute fixer upper, EK van on rotisserie