Turbojack

What are the specs on your cam? From what I have been told you need between 112 & 114 degresss of lobe seperation. What kind of vacuum are you getting at idle, in & out of gear? I am assuming you are not running water to the intercooler while at idle.

Brad Perry

It's got 114 degrees. No water at idle. I didn't pay attention to vacuum.

birdog

I was thinking of Intercoolers this year,but I don't understand about "No water at idle"? Why & how do you achieve this ?Thanks


I richened up the idle on mine also....I helped alot....

boater31

i had to have some surge on mine to get a proper idle for shifting but its not severe. depending on the weather, it will surge a little and quit or just slightly surge the whole time. if i took it all out, the motor died during shifting.

Bird Dog, what do you have in the bullet and what speeds are you seeing? are you running stock bravos? i have a bullet as well.

birdog

Hey 31.....468 ci...BHS Blowers....4lbs boost...
81 mph..GPS.....I am up against the rev-limiters
I need to try some labbed 30,s or ?
Stock Bravos......I baby them BIG time !!!
How about you ?

boater31

i am running 496 strokers w/ 250 blowers and 1280 nickersons. at 5200 its showm 82 on gps but the motor needs to spin 56-5800 to get peak hp. looking at props now but am spinning stock 28 bravos now and need to lab em to get rpms up. this is speed in flat water and trimmed way up. no tabs. havent run in any good chop yet but should pick up a few mph. looking at 2'shorties too as i am running 7-9 on trim indicator to get speed. would like to talk more w/ ya. call me when you can 912-313-8686. Russ

Dennis Moore

I am a firm believer that most high horsepower engines need a heavier flywheel to smooth out the idle. Flywheel weight is an important consideration when designing an engine. Very little attention is paid to this when we modify our engines. Automotive Pro Stock racing engines have huge camshafts and still idle very smoothly. They typically have 40 or 50 pound flywheels with heavy clutch pressure plates(mainly to blast off the starting line with a lot of inertia). I would like to see someone test a supercharged engine with different weight flywheels. I bet the heavy flwheel would allow a monster (stroker) motor to idle like a kitten and be easier on the crankshaft bearings by absorbing crankshaft harmonics (like the balancer in the front of the crank).
Please give me your thoughts.
Sincerely
Dennis Moore
FAMILY AND PERFORMANCE BOATING MAGAZINE

RumRunner

Dennis:

Intereasting thought. I just got back from dynoing a Blower Shop 250 on a 468" we're doing for an article in F&PB. If it wasn't an externally balanced motor that was already together I'd try it for you. I'll get in touch with Marv Hineman @ The Blower Shop I believe the 540" he has may work.


Doug
Tech @ Barry Grant Inc.

P.S. Did you get the bypass we sent out to you ?

Dennis Moore

Thanks Doug,
The bypass looks great, been really busy lately trying to get ahead on the magazine deadlines so I can take some time off for the SEMA and PRI shows (and a little vacation around Christmas).
I will see you at the SEMA show and we can talk then. I would like to do an article about installing a return line to prevent vapor lock within the next few months.
Sincerely
Dennis Moore

RumRunner

Dennis

Not going to make it to SEMA this year, (someone has to stay home and do some work) but I will be at PRI. If you have a few minutes at SEMA stop by our booth and talk to Steve Cole from my advertising dept. Look forward to seeing you @ PRI.

Doug