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Topic Review (Newest First)
11-19-2012 04:14 AM
67Mustang Al.
Quote:
Originally Posted by David 377 View Post
My concern is overheating on the street with too much overdrive heating the air in the supercharger and causing detonation E85 fuel runs cooler right? Anyone have a supercharger with E85 and what do you know about how it works.
We have raced a 3 series BMW here in AUs for the last three yrs using E85 fuel. Yes it runs cooler than our 91 octane pump fuel, but not as cool as methanol. It is harder to start on cold days as well so your plugs may need to be a stage hotter. You need about 30% more volume of fuel going through the injectors to get the dyno hp up. We have around 300 hp out of a stroked 6cyl. (2970cc0) We increased the injector size and duration and run GM triple coil packs and tossed the standard distributor in the bin. With two carbs running E85 + supercharger, you will probably need to up your jet sizes to flow more E85. We havent played with carbs and E85 so it will be a case of research. We have learnt quite a bit over the three yrs with E85 but still learning.
Al.
11-18-2012 10:02 PM
David 377 Thanks guys!
11-18-2012 09:26 PM
bentwings After 22,000 miles on the street with my blown 355 I see little reason to run as much boost as you are planning. Frankly you just can't step on it long enough or hard enough to really get up a head of steam. I can exceed any speed limit in the state in 4 seconds and you can hear the motor, tires and exhaust for several blocks just stepping on it......So can LLE. You will attract them quickly ratting around doing burnouts and what not. Believe me they can appear out of nowhere. So plan on taking it easy on the street.

You are way over thinking the blower. Put a couple 750 dp, referenced carbs and underdrive the blower...either one so you get no more than 6-8 psi boost. If you can get E-85 easily fine run it. You will need a big tank.

You will need an AFR gage to get the tuning right. E-85 will read differently than gas but you will just have to compensate for that. I think you will do well to spend your time studying how the carbs work with the blower and tuning so you can drive easily and reliably in traffic. You will get some really nasty looks and Universal love salutes if you stall traffic or cause problems.
11-18-2012 05:32 PM
David 377 At 12 lb of boost I don't think I need to worry - the car has always rub around 190 - 200 when 80 - 90 degrees. Also blowers produce heat - I guess i'll find out - Thanks
11-18-2012 02:56 PM
techinspector1
Quote:
Originally Posted by mustang 671 View Post
if your bothered about heat introduce some water meth inj to bring the inlet charge down.
The OP is gonna use E85, so I'd be more worried about icing up than I would heating up. You start whippin' alcohol around in a blower case and you can expect some very cold inlet temps.

When you see a crew member spraying WD40 or some other lubricant on the blower hat throttle blades and shafts on an alcohol car at the starting line, that's to help prevent the whole mess from freezing up solid.
11-18-2012 01:48 PM
mustang 671 6/71 due to its size . weight and it requires less bhp to run . if your bothered about heat introduce some water meth inj to bring the inlet charge down . the higher octane the better . think your spot on with your carbs for the street , if you can fit the blower cooler below even better . dont worry too much about the blower spining faster . wetten it up a tad more and it will be fine . torque wise there will be a difference for sure . 8/71 much better low end but 6/71 will be better mid range i feel and watch the 8/71 after 5000 rpm . thats why i would use the 671 as its safer and more suited to your engine size.

good luck
11-17-2012 02:50 PM
David 377 Check thihttp://www.performanceboats.com/pb-open-water/49891-e85-790hp-sbc-epa-carb-complient-supercharged-engine.htmls out!
I guess I found what I needed - Thanks everyone
11-17-2012 09:43 AM
David 377 I appreciate all the input yet alot of what I originally asked has not been discussed. E5 with superchargers - who can answer how much cooler it runs. 8-71 at 1:1 ratio vs 10 overdrive 6-71 - 411 per rev 6-71 - 436 per rev 8-71. How much torque loss will the 8-71 have with the extra air being forced at a lower 1:1.
This car is at 2500 altitude and running anywhere fro 40 degrees to 100 in summer
Bottom line looking for the proper application for this lil puppy motor!?
11-17-2012 01:46 AM
68NovaSS What are you talking about with "torque loss"?? A loss of torque due to fuel inlet temp or heating of the fuel by the blower?

That's waaay over thinking a blown application for the street. That said, I would assume the 6-71 overdriven will generally produce more heat.
11-16-2012 10:47 PM
xxllmm4 Just another thought, from a performance, durability standpoint I would seriouslly consider a modern supercharger. Whipple Industries
11-16-2012 09:51 PM
David 377 Thanks - yet I'm still worried about the torque loss with the 8-71 how much cooler is 1:1 vs. 10 over - is it enough to be concerned or to help keep it streetable?
11-16-2012 09:37 PM
68NovaSS
Quote:
Originally Posted by David 377 View Post
My concern is overheating on the street with too much overdrive heating the air in the supercharger and causing detonation E85 fuel runs cooler right? Anyone have a supercharger with E85 and what do you know about how it works.
You're going to heat the air regardless, a 6-71 overdriven will be spinning faster than the 8-71 at the same boost level. I wouldn't be too concerned about the difference in fuel charge temp at reasonable street rpm's, the 8-71 is capable of higher boost, but you don't really "need" it...did I say that??
11-16-2012 09:31 PM
68NovaSS Also, you don't need to come close to 7k rpm's, the roots blower makes a ton of torque off idle and at low rpm.

Whether it's a 6 or 8-71 isn't the issue with torgue, torque at 10 #'s of boost is what it is, given the same motor specs, regardless of what's bringing that boost on.
11-16-2012 09:29 PM
David 377 My concern is overheating on the street with too much overdrive heating the air in the supercharger and causing detonation E85 fuel runs cooler right? Anyone have a supercharger with E85 and what do you know about how it works.
11-16-2012 09:05 PM
68NovaSS First of all, a 6-71 on a 383 running 10% overdriven is 15.5 pounds of boost, an 8-71 at 1:1 is 14.4 #'s.

Your motor is a 377 so you'd be somewhere in between.

Secondly, a 383 8-71 motor with two BG 750's isn't too much for the street, mine is very well mannered. 850's? depends on the build. 650's? Posing comes to mind.

I don't really understand what your concerned about with this temp thing, but I would shy away from teflon for a street blower, just from a maintenance stand point.
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