i was curious about purchasing a 780 big bore kit for my 02 viper and was wondering if i would need to add anything extra if i did this and was wondering where to purchase one anyone who has one and can tell me what they think of it any input is appresiated thanks 
mopar1rules
Active member
if you don't have the added srx rear heat exchanger, that's one thing you will definetly need. if you get a 780 that uses the stock head, run a hauck or bender super cool headgasket, that's machined open for the 780 bore. run a srx base gasket for stock head or aftermarket head. people to contact on a 780 big bores are mrviper (on this site), cpr, hauck, bikeman, and i'm sure a few others. 780's usually require the rider to keep a better eye on things.....jetting, egt temps, etc.
how much work is it to install the 780 big bore kit and what kind of horsepower gains do you get also how much can i expect to pay for the big bore kit and the other things i need to run it?
mopar1rules
Active member
usually around $2000-$2400. not any harder to install the big bore vs stock bore top end, provided all the machine work on the parts, is done by someone else prior. your power valves will need to be machined (have some for you if needed....need machining yet), the bores need to be bored (i would suggest using blown up cylinders, as its a waste IMO to use good stock bore cylinders), and your head or heads need to be machined. if you are doing the machine work yourself, along w/the assembly of the 780 top end, there is more work, than just dropping on a 700 ported top end.
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