supercharged v8 3.9

slims-v8 · Post by **slims-v8** » Tue Nov 30, 2010 3:49 pm

hi guys, im in the starting progress of building a supercharged with 3.9v8 with my uncle, i've already aqquired the engine, and the manifold, and the only problem being is im unsure of what charger fits onto the manfiold?? the pictures are as follows, any help would be gladly recieved

cheers mark

ChrisJC · Post by **ChrisJC** » Wed Dec 01, 2010 8:11 am

I can't answer directly, but that manifold looks home-made to me, i.e. somebody has modified a standard manifold to take a charger.....

Chris.

slims-v8 · Post by **slims-v8** » Wed Dec 01, 2010 8:58 am

rite, sorry guys have uploaded the pics, but looking at it im guessing it is homemade, because the ally square block on the top has been tigged all the way around,

topcatcustom · Post by **topcatcustom** » Wed Dec 01, 2010 11:13 am

The plate doesn't look square on the manifold from those pics?!

I reckon it is a standard twin carb manifold, and the plate is to fit a 3-71 by the size and bolt pattern?

slims-v8 · Post by **slims-v8** » Wed Dec 01, 2010 8:59 pm

topcatproduction wrote:The plate doesn't look square on the manifold from those pics?!

I reckon it is a standard twin carb manifold, and the plate is to fit a 3-71 by the size and bolt pattern?

sorry that went *wooooosshh* all the way over the top, i get the bit that its doesn't look square on the top, and partially about a twin carb manifold, but a "3-71"?? thats gone right over the top, sorry sp's are new things to me ha ha

kiwicar · Post by **kiwicar** » Wed Dec 01, 2010 9:36 pm

Hi
GMC superchargers come in different sizes, based on the length of the case, the other dimentions are the same. A GMC engine, which gmc superchargers were originall designed to scavange have a standard cylinder displacment of 71 cubic inches, spun at the same revs as the engine a 3-71 will scavenge a 3 cylinder engine (they were 2 stroke deisels by the way), a 4-71 is for a 4 cylinder unit, a 6-71 and 8-71 are obvious up to a 14-71. The point is that the basic supercharger is the same regardless, the end cases, rotor dimensions the lot just the length of the case (and rotors!) changes. A 3-71 displaces 213 ci (about 3.49 litres) per revolution, usefull for about 12psi boost on a 3,5 litre rover spun just under 1:1.
Best regards
Mike

mgbv8 · Post by **mgbv8** » Thu Dec 02, 2010 8:00 am

Thats the home made manifold from Ebay isnt it? I had it on my watch list for about a week or so back. I'm sure it is a normal twin carb mani that has had the top cut off. Still no reason why it wont work though?

kiwicar · Post by **kiwicar** » Thu Dec 02, 2010 10:46 am

Hi Perry
are you thinking of sticking a blower on the MG now? One way of getting all that nitrous to go into the cylinders

. Run it on methanol and you should be able to leave the line with 4 foot flames comming out the ends of the headers

Best regards
Mike

Darkspeed · Post by **Darkspeed** » Thu Dec 02, 2010 6:34 pm

Hopefully he would be saving his pennies for this

http://cgi.ebay.co.uk/DRAG-CAR-TVR-POWE ... 4aa6b92c6e

CastleMGBV8 · Post by **CastleMGBV8** » Tue Dec 21, 2010 8:02 pm

Or one of these.

Nicely made kit for rover engine.

http://cgi.ebay.co.uk/ROVER-V8-ENGINE-T ... 45f7a02e84

Kevin.