Vintage CDI Identification ? ! ?

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Vmax540

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I stole this idea from V.S. and would like to compile a list of Part#'s of CDI's and the numbers/letters that are on the outside of each box for easy identification. Thanks for any help. http://vintagesleds.com/bs/index.php/topic,61054.0.html

Trying to make a chart so, any help/corrections/additions would be great.

1976 SRX440 P#888-85540-10-00 T1A02-06-505
1977 SRX440 P#8F2-85540-10-00 T1A02-11-608
1978 SRX440 P#8G9-85540-10-00 T1A02-13
1979 SRX440 P#8G9-85540-10-00
1980 SRX440 P#8K2-85540-10-00 T1A01-32-906
1980 SS440 P#8K4-85540-10-00
1981 SS440 P# 8H4-85540-20-00
1982 SS440 P# 8N4-85540-20-00
1981 SRX 440 P#8K4-85540-10-00 T1A01-33
1981 SRX 440 (Updated) P#8R9-85540-10-00 it is used with the 8R9 stator
1983-86 Vmax P#8U9-85540-10-00 TIA01-43
1987-1991 Vmax P#83H-85540-10-00

On another note Speaking of Vmax540's and their CDI failures...... I ran into an older guy at a grass drag a month ago, who was into SRX's and Vmax540's back in the day and he said get the Original 81 SRX or 1980(?) SS440 CDI which has a straight timing curve and is very reliable he said this will end your CDI failure problems. He said you need to run a jumper to ground with this setup and could not remember exactly how ? Anyone seen this done ?
 
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the original srx cdi put out a flat timing curve, this curve was only 8 degrees.

The "new 8r9" box is the srx500 box, this cdi gives 12 degrees MORE advance at 5000rpm then the original 81 box, the curve is steeper thru out the rpm band and ends in near the same degree point. For those of you adding this up, yes, it has 20 degrees advance at 4000rpm, not 8. They did this is help accel. the engine and it ended up working and making more power all the way thru the rpm curve(which isnt very big on a srx440)...lol

the curve retards as the rpm goes up for topend power, ends at the same 8 degrees at 9000rpm
 
I believe the 1981 SRX number (early) may be incorrect
I have a brand new one in my hand and it reads
1981 SRX 440 P#8K4-85540-10-00(parts label) and hot stamped on the unit- T1A01-33 (not 38 )
WOT
 
YAMMIEGOD3:16 said:
THAT IS THE CORRECT BOX FOR THE 81 SRX BEFORE THE UPDATE TO THE 8R9. 3:16 (yammie tony)
Click to expand...

So, the early number I was given T1A01-38 what is it from or were there 3 different versions ? Be nice to get this correct.

1981 SRX 440 P#8K4-85540-10-00 T1A01-38
1981 SRX 440 (Updated) P#8R9-85540-10-00
1981 SRX 440 P#8K4-85540-10-00(parts label) and hot stamped on the unit- T1A01-33 not 38
 
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Vmax540 said:
So, the early number I was given T1A01-38 what is it from or were there 3 different versions ? Be nice to get this correct.

1981 SRX 440 P#8K4-85540-10-00 T1A01-38
1981 SRX 440 (Updated) P#8R9-85540-10-00
1981 SRX 440 P#8K4-85540-10-00(parts label) and hot stamped on the unit- T1A01-33 not 38
Click to expand...
Well I was thinking someone might have just mis-read it. I even had to use a magnifying lens to determine it was in fact a 3 not an 8. Someone with an 81 owners manual should be able to tell us for sure. Yamaha almost always put the Hitachi numbers in their OM spec sheets. (I see them listed my OM for the 1978 SRX p.60 )
It lists the 78 CDI as T1A02-13
YAMMIEGOD3:16 said:
THAT IS THE CORRECT BOX FOR THE 81 SRX BEFORE THE UPDATE TO THE 8R9.[font=Calibri","sans-serif]THAT WAS A VERY HOT CDI BOX AND WORKED GREAT FOR RACING. [/font] 3:16 (yammie tony)
Click to expand...
Yammie Tony, I was aware it was a "hot" box with a higher rev limit etc. than the 78-80 units. But do you (or anyone else) have any timing curve data for it?
I believe it still flats out at 8 degrees @9K but havnt observed that for myself yet.
Thanks
WOT
 
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Not to change the subject but has anyone ever tried one of those aftermarket cdi boxes (cdibox.com)? I was thinking of going that route after reading reviews?
 
My 81 Yamaha service manual has the original CDI # as T1A01-33 HITACHI. I agree with Tony I know of only two CDI's for the 81.The original had only 8 degrees advance, and the 8R9 the updated one had about 20 degrees advance and retarded back after 7000 rpm's to 8 degrees at 9000 rpm's . The 8K4 or original one is the same one that the 80 SS440 used as well.
 
vmax-540 said:
My 81 Yamaha service manual has the original CDI # as T1A01-33 HITACHI. I agree with Tony I know of only two CDI's for the 81.The original had only 8 degrees advance, and the 8R9 the updated one had about 20 degrees advance and retarded back after 7000 rpm's to 8 degrees at 9000 rpm's . The 8K4 or original one is the same one that the 80 SS440 used as well.
Click to expand...
Thanks for the verification!
That's all sounds 100% I have some notes from an early 80s Yamaha competition bulletin that says you can use the 1st design T1A01-33 as a replacement box for oval racing the 76-80 SRX. So the flat advance @8 degrees would make a lot of sense for an sled being essentially "pinned" at 9500-9700 RPM for 5-10 laps.;)!

Does your parts/service manual list the "holder" for the 81 CDI box by chance? In the the earlier SRX they were directly bolted down. But from the pics I have it looks like this CDI box (which is a different shape/design) was held/isolated in a square rubber fixture of some sort then fixed by just a wire tie?Must find one.
Thanks
WOT
 
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The part# for the rubber holder is 2A7-85546-00-00. The metal bracket that the rubber slides into was spot welded on the sled, they should be easy to make. The rubber was used on the 81 SRX & all year SS 440's Phazers, SRV's & a lot of other models. Should be easy to find & or order new.
 
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