Spal Radiator Fan Specification
Discussion
This is just for information and to help others who are looking to buy a replacement fan for their TVR Chimaera. Firstly and to be clear my car is a late 1996 (early facelift) so please consider this when reading on, TVR used fans from Spal which are extremely high quality but as always with TVR the exact specification of the parts used may vary from year to year.
Like all Chimaeras my car is fitted with two rad fans, in my case the N/S one is of a straight blade design while the O/S fan has curved blades, I have discussed the differences with the Spal technical department who confirmed at peak rpm both blade types will shift exactly the same amount air. However, the curved blade fan will shift more air at low rpm. This is only an advantage on fan startup (first few seconds) but it should also be noted along with the extra air the curved blade fan will draw more amps on startup.
In my case TVR used of one straight blade and one curved blade fan, this combination has certain advantages so I've stuck with the curved/straight setup. I did not explore the exact part number for the straight blade fan, a quick call to Spal will confirm what you need if you're looking for a straight blade model but I can tell you at peak rpm they both draw 14.2amps but they will also spike much higher than this on initial startup so make sure your fuses & relays are up to the job.
Some time ago Bluebottle recommended calling Spal direct on 01905 613714 as buying direct proved cheaper (thanks Bluebottle), on his advice I called the sales & technical team on this number today and found them very helpful and their prices better than I could find elsewhere.
The part number of the O/S curved blade fan originally fitted to my 1996 Chimaera is: VA10-AP50/C-61A
When broken down here is what the code tells us:
As an upgrade to the original VA10-AP50/C-61A Spal offer model VA10-AP70/LL-61A, this fan has the same newer 61A blade design earlier cars being fitted with a 47A design. The uprated VA10-AP70/LL-61A model actually shifts the same amount of air as VA10-AP50/C-61A, the only difference is it has a stronger long life motor (LL). The long life motor is 25mm deeper than the standard life (C) motor too, but there's plenty of room to accommodate it in a Chimaera engine bay.
All these fans use traditional brush type motors, the brushless motor fan to match VA10-AP70/LL-61A comes with soft start technology and draws less amps but is a whopping £200 more expensive (per fan).... so I didn't bother to explore this option further.
The final post Brexit 2017 price for the uprated motor VA10-AP70/LL-61A including V.A.T and next day delivery to a UK address (after I negotiated a 38.46% discount) was £131.95, Spal's stock ordering code for this fan as stated on the invoice is 102029A.
I hope this helps someone needing to replace their O/S curved bladed Spal fan on their TVR Chimaera? Please check what you currently have fitted to your radiator before ordering as TVR were notorious for making changes, as stated my car was built in late 1996.
Dave.
Like all Chimaeras my car is fitted with two rad fans, in my case the N/S one is of a straight blade design while the O/S fan has curved blades, I have discussed the differences with the Spal technical department who confirmed at peak rpm both blade types will shift exactly the same amount air. However, the curved blade fan will shift more air at low rpm. This is only an advantage on fan startup (first few seconds) but it should also be noted along with the extra air the curved blade fan will draw more amps on startup.
In my case TVR used of one straight blade and one curved blade fan, this combination has certain advantages so I've stuck with the curved/straight setup. I did not explore the exact part number for the straight blade fan, a quick call to Spal will confirm what you need if you're looking for a straight blade model but I can tell you at peak rpm they both draw 14.2amps but they will also spike much higher than this on initial startup so make sure your fuses & relays are up to the job.
Some time ago Bluebottle recommended calling Spal direct on 01905 613714 as buying direct proved cheaper (thanks Bluebottle), on his advice I called the sales & technical team on this number today and found them very helpful and their prices better than I could find elsewhere.
The part number of the O/S curved blade fan originally fitted to my 1996 Chimaera is: VA10-AP50/C-61A
When broken down here is what the code tells us:
- VA10 = 12" (305mm)
- AP50/C = Standard motor type / standard life
- 61A = Blade reference - in this case Spal's latest curved blade design that has now superseded the older 47A curve blade design
As an upgrade to the original VA10-AP50/C-61A Spal offer model VA10-AP70/LL-61A, this fan has the same newer 61A blade design earlier cars being fitted with a 47A design. The uprated VA10-AP70/LL-61A model actually shifts the same amount of air as VA10-AP50/C-61A, the only difference is it has a stronger long life motor (LL). The long life motor is 25mm deeper than the standard life (C) motor too, but there's plenty of room to accommodate it in a Chimaera engine bay.
All these fans use traditional brush type motors, the brushless motor fan to match VA10-AP70/LL-61A comes with soft start technology and draws less amps but is a whopping £200 more expensive (per fan).... so I didn't bother to explore this option further.
The final post Brexit 2017 price for the uprated motor VA10-AP70/LL-61A including V.A.T and next day delivery to a UK address (after I negotiated a 38.46% discount) was £131.95, Spal's stock ordering code for this fan as stated on the invoice is 102029A.
I hope this helps someone needing to replace their O/S curved bladed Spal fan on their TVR Chimaera? Please check what you currently have fitted to your radiator before ordering as TVR were notorious for making changes, as stated my car was built in late 1996.
Dave.
David Beer said:
Thank goodness you changed the current draws you last posted! Good work on updating.
Thanks David, if you look back I stated an assumption of amps based on the Spal code format, at the time I was clear this was an assumption on my part and never claimed it as fact.I have also been careful to provide the true breakdown of Spal's code format which helps correct posts made by others were information has been misleading at times.
The purpose of this post is simply to help others which for me is the essence and function of the forum, by contrast I suspect the purpose of your comment above is some what different.
A few key points to finish:
- The original VA10-AP50/C-61A fitted to my car is still available from Spal and is roughly £60 cheaper so almost half the price of the long life VA10-AP70/LL-61A with the bigger motor
- VA10-AP50/C-61A and the long life VA10-AP70/LL-61A I purchased shift exactly the same amount of air, the only differences are the VA10-AP70/LL-61A has virtually double the estimated working life and it's motor is 25mm deeper
- All the other dimensions (VA10 = 12"-305mm) of the two options are identical and both will fit a Chimaera
- The 61A fan blade type supersedes the older 47A type, Spal still have some 47A type fans in stock in both standard and long life configurations which are being offered at a discounted price
SILICONEKID345HP said:
How do both operate? One then the other or both together.
On the standard setup both fans are wired to the same otter switch, and both fans chime in simultaneously.On my setup fan one is controlled by my Canems ECU which uses the coolant sensor in the cylinder head, fan two is triggered by the original otter switch screwed into the bottom of the swirl pot. As such fan one & fan two can be configured to chime in at different times but they do function in a temperature range that crosses over each other.
Staggering the moment each fan starts up helps to reduced the high amp spike seen when both fans are configured to start simultaneously... as with the original arrangement.
[quote=ChimpOnGas]
Thanks David, if you look back I stated an assumption of amps based on the Spal code format, at the time I was clear this was an assumption on
The purpose of this post is simply to help others which for me is the essence and function of the forum, by contrast I suspect the purpose of your comment above is some what different.
I did say on the post the info was not right , in the interest helping others. Still all ok now.
Thanks David, if you look back I stated an assumption of amps based on the Spal code format, at the time I was clear this was an assumption on
The purpose of this post is simply to help others which for me is the essence and function of the forum, by contrast I suspect the purpose of your comment above is some what different.
I did say on the post the info was not right , in the interest helping others. Still all ok now.
SILICONEKID345HP said:
I just don't have the time and energy do do these brilliant mods ..
"these brilliant mods"?Mate, what I have is really not that complicated, lets break it down....
1. Disconnect one fan from your standard otter switch triggered arrangement
2. Use a temp triggered output from your Emerald ECU to trigger the second fan
3. Choose an otter switch value that can maintain coolant at idle at 90 degrees with just one fan
4. Use your ECU software to tune the on/off temps of the second fan so the period both fans are on is minimised and idle temps do not exceed 88 degrees
You're looking to keep your coolant temps within the tightest window possible either side of an 85 degree target, I aim to achieve a maximum of 88 degrees at idle on a hot day and min 83 degrees at speed on a cold day.
The truth is I can momentarily hit 92 degrees at idle on a hot day but the fans immediately bring this down, without a rad blind my running temps at speed in ambient temperatures below 10 degrees are 78 degrees although this is dependent on how quickly I join the motorway and start driving at speed after a cold start. If I get stuck in traffic before joining the motorway then even on a cold day my at speed coolant temps will be 80 degrees, on a hot day with no winter rad blind used my coolant temp at speed is maintained at 85 degrees.
A rad blind in this weather is definitely a good idea but be careful not to restrict air flow through the rad too much, I've tuned the size of my blind so my winter running temps at speed are kept at 83 degrees. However, my winter rad blind does influence idle temps too. Without it my average idle temps are maintained at 88 degrees irrespective of ambient temps, with the blind my average winter idle temps are closer to 90 degrees.
Fitting and sizing a winter rad blind is therefore a balance between keeping the running temps at speed as close to 85 degrees as possible while keeping the average idle temps no higher than 90. Obviously the TVR temp gauge is not to be trusted and really isn't accurate enough to tune your coolant temps, I have also found running a 88 degree thermostat during the winter works best and there are no issues with it in the summer either so it remains in all year round.
I do however run with all three cats removed from the exhaust system and my idle ignition timing is way more advanced than a standard Chimaera on a distributor, both these elements help to reduce my idle temps. I can also see my true coolant temps using my Canems software which has allowed me to fine tune my fans and the rad blind which is only used in the winter. As soon as ambient temps go above 12 degrees I remove the blind completely which is normally around the first week in April, it typically goes back in around the last week of October but all this does very much depend on the weather we're having that year.
Edited by ChimpOnGas on Wednesday 11th January 07:31
ChimpOnGas said:
SILICONEKID345HP said:
I just don't have the time and energy do do these brilliant mods ..
"these brilliant mods"?Mate, what I have is really not that complicated, lets break it down....
1. Disconnect one fan from your standard otter switch triggered arrangement
2. Use a temp triggered output from your Emerald ECU to trigger the second fan
3. Choose an otter switch value that can maintain coolant at idle at 90 degrees with just one fan
4. Use your ECU software to tune the on/off temps of the second fan so the period both fans are on is minimised and idle temps do not exceed 88 degrees
You're looking to keep your coolant temps within the tightest window possible either side of an 85 degree target, I aim to achieve a maximum of 88 degrees at idle on a hot day and min 83 degrees at speed on a cold day.
The truth is I can momentarily hit 92 degrees at idle on a hot day but the fans immediately bring this down, without a rad blind my running temps at speed in ambient temperatures below 10 degrees are 78 degrees although this is dependent on how quickly I join the motorway and start driving at speed after a cold start. If I get stuck in traffic before joining the motorway then even on a cold day my at speed coolant temps will be 80 degrees, on a hot day with no winter rad blind used my coolant temp at speed is maintained at 85 degrees.
A rad blind in this weather is definitely a good idea but be careful not to restrict air flow through the rad too much, I've tuned the size of my blind so my winter running temps at speed are kept at 83 degrees. However, my winter rad blind does influence idle temps too. Without it my average idle temps are maintained at 88 degrees irrespective of ambient temps, with the blind my average winter idle temps are closer to 90 degrees.
Fitting and sizing a winter rad blind is therefore a balance between keeping the running temps at speed as close to 85 degrees as possible while keeping the average idle temps no higher than 90. Obviously the TVR temp gauge is not to be trusted and really isn't accurate enough to tune your coolant temps, I have also found running a 88 degree thermostat during the winter works best and there are no issues with it in the summer either so it remains in all year round.
I do however run with all three cats removed from the exhaust system and my idle ignition timing is way more advanced than a standard Chimaera on a distributor, both these elements help to reduce my idle temps. I can also see my true coolant temps using my Canems software which has allowed me to fine tune my fans and the rad blind which is only used in the winter. As soon as ambient temps go above 12 degrees I remove the blind completely which is normally around the first week in April, it typically goes back in around the last week of October but all this does very much depend on the weather we're having that year.
Edited by ChimpOnGas on Wednesday 11th January 07:31
Have you LED's on or in the dash that inform you that the power supplies and returns are present at the cooling fan motors?
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