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roverman
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Anyone using HTD or round tooth profiles ? Has anyone adapted VVT, onto their 907+ ? Vernier sprockets ? Sources for either drive profiles, to fit 907's ? What is the "wildest" cam spec's, heard of, for a racing 907 ? Thanks, roverman.

gmgiltd
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Just ordered a vernier HTD kit from Mike Taylor at Lotusbit's along with the later Lotus belt tensioner and adapter to suit - not installed yet but looks like a good improvement on the standard kit. The cams I have are supposed to be timed at 104 MOP.
There is a very good spreadsheet by Tim Engels which lists all the alternative cams with loads of useful data.

http://www.theymightberacing.com/Projects/FrameOff/JH74G/Docs/Cam_-_Data_-_9XX.xls

roverman
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Thank You, roverman.

Jensen Healey
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QED also has the vernier pulleys. http://qedmotorsport.co.uk/
I haven't heard of anyone adapting VVT.
Kurt

roverman
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More likely to happen in phase II , with Zeus heads ? Could this be the first 32 valve rover V8 ? Cheers, roverman.

roverman
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Work is progressing well,on the "Rotus V8", modular cams. Plan is to use Honda/Acura adjustable cam sprockets,(round tooth).Plan is to support each cam with (3) split, and (2) non-split needle bearings. Cams will be approx. 40% lighter,than oem. Induction will be (4) 44mm IDF Webbers,(nostalgia look). Cheers, roverman.

Jensen Healey
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Photos?

roverman
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Not quite far enough along, for enlightening photos. I'm currently working on the modular cams, which should be approx. 40% lighter,(4 oems weigh 30.25lbs.). Richard at WCRCH, suggest port injection, for easier/better tune, under all conditions. I want nostalgia look of IDFs', but not the hassle, so may use them as 48mm TBs', minus the chokes, for more airflow. Using Honda/Acura adjustable cam sprockets. I may use a billet crank for durability,3.315" stroke, this allows use of a light sbc 6" rod and forged 305" sbc piston. Onward, roverman.

Esprit2
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roverman wrote:
What is the "wildest" cam spec's, heard of, for a racing 907 ? Thanks, roverman.There are a lot of aftermarket cam grinders offering street, rally & race cams for the 9XX engines. You'll just have to shop around. Start with Cosworth, Dave Bean, Dave Smith, Elgin Cams, Garry Kemp, Kent Cams, Paeco, Piper Cams, etc...

Note that "104" has become synonymous with "hot-street", and there are a number of aftermarket "104" cams available that don't match the factory specs for a Lotus 104 cam. Do your homework before buying.

For Lotus factory cams, it's:
Cam ID Part No ...... Old Part No ... Lift .... Duration.. MOP ......... Use
101 (C) F907E0101, C907E0351Z... 0.340 ... 272° .... 110° ......... 907 Lotus Fed & J-H
102 (D) G907E0102 D907E0351Z... 0.350 ... 270° .... 110° ......... 907 Lotus Euro
103 (E) J907E0103.. E907E0351Z... 0.344 ... 260° .... 102.5° ...... 907 Late & 911 Talbot
104 .... A912E0104 ...................... 0.420 ... 272° .... 104° ......... 912HC Lotus (Inlet only)
105 .... A908E0105 ...................... 0.433 ... 296° .... Per event... 911 Sunbeam Rally
106 .... A908E0106 ...................... 0.450 ... 320° .... Per event... Motorsport Cam
107 .... A912E0107 ...................... 0.378 ... 252° .... 104° ......... 911, 912 & 910
108 .... A908E0108 ...................... 0.460 ... 304° .... Per event... Motorsport Cam

101, 102, 103, 104 & 107 are Lotus street cams, used in series production engines.

105, 106 & 108 are Lotus Motorsport cams. Good luck getting your hands on one of them... it probably won't happen.

Cam Names:
The old letter names (C, D & E) come from the old Lotus part number's letter prefix.
The number names come from the last three digits of the new Lotus part numbers.

Last edited on 06-19-2014 05:45 pm by Esprit2

roverman
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Schneider Cams has int/exh. profiles I like. Intake likely 298deg. adv., with .460" lift, minus clearance. 286deg. with .429"lift exhaust. Thanks, roverman.

roverman
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Honda aftermarket sprockets are advertized as 7075 T6 billet aluminum/chinese. My rockwell hardness test confirms this. More difficult, will be finding Honda size crank sprockets, that will bore to RV8 crank snout size. Onward, roverman.

dwalls1
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Put a set of 1/2 moon pulleys and a T188 belt on about a year ago. Got the set off E-Bay from a private seller at a smokin' deal. Doing great and should get at least 30 thou miles, which is several years in J-H miles. And the black anodizing looks cool.

roverman
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Would this be a 3/8" pitch belt ? Honda/Acura measures this. Thanks, roverman.

Esprit2
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The stock J-H/ Lotus/ Gates T188 are 3/8" pitch Imperial belts... if that's what you're asking.