6-71 or 8-71 blower on a '55 331 hemi

tryn to get an idea of what size of blower i should go with on my 331....i want this to be a beast. Ive heard that jumping up to the 8-71 would run cooler and obviously give me desired boost levels at less work on the blower. Gonna keep compression down to i believe 8:1. Also been told that I may have idle issues. HELP....any thoughts would be appreciated. Where the hell is Big Daddy Don Garlits when ya need him?

 

For a street car, a 6-71 with 6-10#s of boost will scare the shit out of you, I promise. No real need for the added expence of an 8-71. (and no, it won't run cooler than a 6-71)

Hit the search button for lots of good blower stuff...there are even a few guys with blown early Hemis that have stockpiled ass loads of knowledge.

Good luck, -Abone.

 

Agree, and the 6-71 is way more traditional.

 

I am no expert, but from what I have gathered so far on my 392 blown project, I would say 4-71 for the street, 6-71 for a bit of actual racing and 8-71 for full blown racing.

 

Well my opinion and 25 cents will not buy you a cup of coffee, but hear it is....

I have an 871 on a 409 Chev in my street driven hot rod with no problems at all.... Second, I run an 871 on my 392 hemi, nostalgic drag car, with no problems at all, however; two very different animals...

Do not listen to strictly drag guys for advise on your street driven hot rod with a blower, underdrive your blower for a street application with the max. of 8:1 compression.... Drag guys run everything too the limit, I know this for a fact !!!

I would certainly use the 671 for your 331.... 871, too much for a 331.

When you are referring to the motor running cooler with the 871, you may have mixed up a few details. The 871 allows more air and fuel than the 671 "using the SAME pulleys/drive ratio"... Too achieve the same boost with the 671 as compared to the 871, you have to increase the rotor RPM in the blower which results in more heat, remember you are squeezing air and fuel which creates heat.... Therefore; you have a hotter intake charge into the motor.... This is NOT an issue for a 331 blown street hemi....

You will not have idle issues with a 671 and it will give you the ride of your life and yes, it will be a beast which is your desire....

Have fun, there is nothing like a blower.....

 

Ive played with blowers before.....just not a lot of easy access info for early chrysler....I have a book thats got some great info on building a strong Chrysler 331-354-392...but its vague in some areas....like which blower is the best bet....blah blah blah. Appreciate the replies so far. If only the alliance was teamed with hot heads

 

Now that would be nice! I've never ran a blown Hemi but they sure do look great!