Rover V8 Boxer carb installation blog

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Riley RMF
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Re: Rover V8 Boxer carb installation blog

Post by Riley RMF » Wed Mar 21, 2018 9:50 pm

Video clip of my engine bay walkaround here:




And the initial start:




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ChrisJC
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Re: Rover V8 Boxer carb installation blog

Post by ChrisJC » Thu Mar 22, 2018 4:32 pm

Nice videos. It will be interesting to see the improvement when it's set up properly.

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Riley RMF
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Re: Rover V8 Boxer carb installation blog

Post by Riley RMF » Tue Mar 27, 2018 5:41 pm

Next instalment, first pass on getting the timing and carbs setup now available:


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Re: Rover V8 Boxer carb installation blog

Post by Riley RMF » Thu Jul 12, 2018 4:08 pm

Been working on other parts of the car for a time, but an opportunity to play around with the carbs this morning.

Just to recap, my engine is a 3.9 recon unit with TVR internals and so is a 4.3. Standard 3.5 heads, so a bit of a mongrel, but it will do what I want. For the time being at least. HIF44 carbs

I've fitted BBG needles as per the Fast Car article posted previously, and yellow springs - standard on the 3.5.

So here's my logic on the springs. I've got 23%ish more air flowing into the engine, so I'm using more of the needle range than I would have done with a 3.5. It's not going to be ideal, but it should work.

Balanced up all the carbs and the engine is now running really nicely. The car isn't driveable yet, so this is just stationary in my garage, but it seems pretty happy.

It'll probably be 3 months or so before I can actually hit the road so next update when that happens...

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Re: Rover V8 Boxer carb installation blog

Post by Darkspeed » Sat Jul 14, 2018 6:43 pm

You may have more engine capacity but with stock heads you have the same air flow. The increase in capacity will just mean things are all over by 4800RPM rather than 5300RPM - (figures are just arbitrary for example). Calculation for establishing the lower RPM maximum horsepower will occur at for the same head flow figure but larger capacity will be easy enough to find.

Not sure what you mean by using more of the needle range because unless you have the heads opened up to flow more air you will be using exactly the same as the 3.5 as they strangle that capacity. -Heavier spring just makes and SU richer for a given air flow - Lighter spring weaker - Engine capacity actually has little bearing on what goes on - apart from when the carb tops out on ultimate flow potential.

Yellow appears to be quite a strong spring so much richer . What the overall effect is you won't know until doing some WOT under load testing.
4.5L V8 Ginetta G27

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