52mm throttle body upgrade on 05 TF 115

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ArntyR
Posts: 323
Joined: Fri Feb 06, 2015 8:37 am
MGF Register Region: South East
Model of Car: 2010 TF135 Style
Location: West Sussex

52mm throttle body upgrade on 05 TF 115

Post by ArntyR » Tue Oct 10, 2017 8:55 am

Hi All, just wanting to share…

I noticed an eBay offer for a larger 52mm throttle body and wondered how it would affect my placid ’05 TF 115. After research (thanks to all the forums) I found the Trophy owed much of its sportiness to an upgrade from a 48mm* to a 52mm dia tb (I gather their removal of the internal ‘wedge’ is beneficial too) - and a nearly 20% increase in fuel/air throughput ought not to be sniffed at.

I bit the bullet and ‘new’ seemed better v-f-m. Most Fs and TFs have 48mm tbs and some are plastic, so 52mm aluminium seemed an improvement imo.

Perhaps it was as much due to the fact that possible throttle slack was adjusted, rather-too-loose inlet studs were ‘sorted’, jubilee clips were added and existing clips tightened etc but the overall effect has been a much better throttle response, stronger idling and better low-speed engine stability. No major speed or bhp increase, though.

Originally concerned by possible idling inconsistencies, I did a throttle sensor reset cold and again when more fully warmed (I wish I hadn’t jumped the gun- just to see if it would have been a problem…) and idle speed has been maintained at 750 – 800 rpm when warm; a little more when cold, just as before…I’d expected to have to transfer my original tb sensor but there was absolutely no need.

Overall? I thought nearly £70 inc vat + del was definitely well spent in my case and a used tb might halve the price, giving even better v-f-m. Much better driveability plus a shiny new piece of kit to slurp over. I'm interested to see how fuel cons might be affected, if at all.

*(Apparently the 48mm SU tb was the last offering to MG/Rover from this firm, since the 52 mm upgrade was a Dellorto design.)

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talkingcars
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Joined: Tue Mar 09, 2010 10:44 pm
MGF Register Region: South East
Model of Car: mk1 VVC
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Re: 52mm throttle body upgrade on 05 TF 115

Post by talkingcars » Tue Oct 10, 2017 9:46 pm

ArntyR wrote:......but the overall effect has been a much better throttle response, stronger idling and better low-speed engine stability. No major speed or bhp increase, though.......
Much the same as most find, defiantly worth doing for drivability.
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