Originally Posted by 8490
:cry: need help i have a blown small block chevy 406 ci. 11.0 comp. 8-71 blower big ugly injection, afr 210 heads, it has in hat it has 37 nozzles and port has 37 nozzles we have tryied by passes from 60 to 105 does not make any differance had pump rebuilt what kind of tune-up is someone else running
thanks
To answer your question without the rhetoric or telling you what we have (which is moot in your request for help)...
Is there anything wrong with Alky and 11:1? No. Is 11:1 "perfect" for compression? Maybe, maybe not. It all depends on cylinder heads and blower efficiency. There is no perfect compression ratio and all of the current top alky teams that I converse with are running different compressions.
The big and ugly, while maybe not the best choice, it certainly looks cool as shit, and will work just fine. Change your barrel valve linkage from 1:1 to accelerate the barrel valve open quicker as you depress the throttle. This will compensate for the large surface area opening of the butterflies.
If you're changing main jets from 60-105 and not seeing any changes in the performance, the tune up is soo far off it doesn't matter what you do.
Once again, I will point you, like many others, to Bob Szabo's book (I should ask Bob for commission sales)...
www.racecarbook.com
It contains ALL of the formulas needed to setup an alky injected motor, so long as you know what your fuel pump and nozzles flow.
Without knowing:
1. CID
2. Compression Ratio
3. Blower size/style/stripping/manufacturer (CID if you have it)
4. Over/Under drive ratio
5. Fuel pump flowed GPM @ 100 PSI @ 4000 pump rpm
6. Hat/Port Nozzle Sizes
I don't know anyone who can spit out the magic tune up based simply on hat/port nozzle and main jet size.