SpeedTalk Store - Opinion Columns

methanol A/F ratio on race engine

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Postby hellfirejim » Wed Jun 20, 2007 7:40 am

Air fuel ratio for an alky motor is between 5 to 6 to 1. It sounds like you are way to rich. However I will say the rich is far better than lean.

The advice you got on how to set up the fuel injection was very sound and works in the real world.

when you get to the track once you have a safe setup, tune for lowest et to the 1/8th mile. Once that is established you can then start to bend the fuel curve over by using the high speed. Though I believe a dyno is great and highly recomend one, nothing beats tuning in the real world.

jim
hellfirejim
 

thats why!

Postby seefour » Wed Jun 20, 2007 4:56 pm

Thata why I installed a wide band 02 in the car so I could see whats going on, I know nothing beats real world tuning but the wide band 02 is a tool just like any other tool. its to be used, just like egt and water temp.
I have one year experience with a single toilet and the new motor is bigger and has 2 toilets. I over shot the choice of pills for the nozzels wich I take into account.


thanks Mike S
Do it right the first time
seefour
Member
Member
 
Posts: 192
Joined: Sun Jun 17, 2007 12:10 pm
Location: Brenham Texas

should I say

Postby seefour » Wed Jun 20, 2007 7:49 pm

I didnt foul any plugs or lose any cylinders

Mike S
Do it right the first time
seefour
Member
Member
 
Posts: 192
Joined: Sun Jun 17, 2007 12:10 pm
Location: Brenham Texas

Postby hellfirejim » Wed Jun 20, 2007 8:09 pm

Just something that happened to me. With the blown alky funny car we wanted to see just how rich we could make it and it still run. We had it so rich raw alky was coming out of the pipes and it was a soggy pig but it did run......

The point of what I am saying is just because you didn't foul the pulgs and/or drop a cylinder does not mean that you were not too rich. The beauty of alcohol is the it CAN be run rich and still run unlike gasoline.

Good luck with the chase to find your problem and i would be interested in what you find out. always willing to learn sometyhing new.
jim
hellfirejim
 

didnt take it that way

Postby seefour » Wed Jun 20, 2007 9:02 pm

I mean it was rich , I know that. Im talking about hydlalicing the motor or beating the bearings out. I didnt take any offense to your statement

thanks
Mike S
Do it right the first time
seefour
Member
Member
 
Posts: 192
Joined: Sun Jun 17, 2007 12:10 pm
Location: Brenham Texas

I changed pills today

Postby seefour » Thu Jun 21, 2007 7:18 pm

I changed pills today and just the idle mixture a/f came up to 4.0 from 3.2
during the chassis dyno pass the highest a/f reading I got was 4.8 so thats a change of .16
, if at 4.0 I get the same change it will be 5.6
I might need the 33's after all on pill size but i will wait and run it at the track

Mike S
Do it right the first time
seefour
Member
Member
 
Posts: 192
Joined: Sun Jun 17, 2007 12:10 pm
Location: Brenham Texas

Postby 358T » Thu Jun 21, 2007 8:54 pm

Seefour,

Good choice talking with James. He's the man with Ron's systems. Bill Jones has also given you some very good info.

Can you post a link to CHI's website? You have a 4" stroke but only 410" inches... that must have a small bore. IMO, 785hp is pretty optomistic for that shortblock and those heads.

But anyway, back to your problem. I run a 421"sbc that I would consider to have somewhere around 750ish corrected HP. It has an old set of Brodix-12 15* heads on it. It runs 7.7's at 173 in good air at 1690lbs. It is Ron's injected. I run a waterman .500 pump and a 35 nozzle with a 92 main pill. The waterman 500 pump puts out slightly less fuel than a 0 1/2 rons twin gear or black pump. Which 0 1/2 pump do you have?

Going by your wanted HP and the looks of your combo I'd say 650-675hp max. Therefore you'll probably end up with a 31 or 32 nozzle and a mid to high 90 pill if you have a 0 1/2 black or twin gear pump. We build a 414 that ran high 7.8's in good air at 1620lbs and that is the nozzle, pill, pump combo it used. If its a gold and/or vane pump the tuneup may be different depending on what shape the pump is in.

How old is the injection system? Is it a toilet or terminator?

Scott
User avatar
358T
Pro
Pro
 
Posts: 304
Joined: Mon Sep 06, 2004 7:04 pm
Location: Highland, Illinois

well its ...............

Postby seefour » Thu Jun 21, 2007 9:12 pm

Well its a toilet system.
two toilets 1435 cfm each
beck mechanical sheet metal intake
CHI 3v heads flowed 340/240 cfm on 4.0 bore 218 cc runners, ports cc'd
4.0 stroke, 6.0 rod,14.0 compression
comp roller .775-.757 lift 266-274@.050 295-306 duration 108 sep 1 degree advanced 104-112 but is 107-109
moroso vacume pump, JE low tension rings
all manely vave hardware
crower sever duty roller lifters and rockers.
MSD cranktriger and ignition 7 Al2 box with there best coil , mutlifunction ignition controller
hearers at 1 7/8 x 3.5 collector

it better make more than 675, many people have made 700 plus on pump gas

bore is 4.04,

www.chiheads.com

check out the car and motor on
http://www.youtube.com/stangofnitro



thanks
Mike S
Do it right the first time
seefour
Member
Member
 
Posts: 192
Joined: Sun Jun 17, 2007 12:10 pm
Location: Brenham Texas

Postby clevo » Mon Jun 25, 2007 1:08 am

seefour :D
You are way too rich, you want the A/F between 5.3&5.6
We just finished an Injected 400 SBC 800hp at 7100rpm :wink:
Downunder
clevo
Pro
Pro
 
Posts: 208
Joined: Tue May 23, 2006 10:06 pm
Location: Australia

GOT IT

Postby seefour » Mon Jun 25, 2007 5:16 am

GOT IT ! 5,6-5,8 YESTERDAY AT TRACK
i HAVE TRACTION ISSUES BUT STILL RAN 6.19 1/8 MILE AT 112


mIKE S
Do it right the first time
seefour
Member
Member
 
Posts: 192
Joined: Sun Jun 17, 2007 12:10 pm
Location: Brenham Texas

Postby hellfirejim » Mon Jun 25, 2007 7:11 am

Congratulations!!! :D It's like any problem, perserverance pays off. How much better do you think it will get?

jim
hellfirejim
 

MUCH BETTER

Postby seefour » Mon Jun 25, 2007 3:42 pm

I HAD A 1.443 60 FT ON THAT PASS, CANT USE 1ST GEAR AT ALL, MUCH REST CALTRACS AND TRAVEL LIMITERS, CAR NEVER GOT ON REAR TIRES, SHIFTING AT 6600 RPM
I THINK IT WILL GO 5.90'S EASY

MIKE S
Do it right the first time
seefour
Member
Member
 
Posts: 192
Joined: Sun Jun 17, 2007 12:10 pm
Location: Brenham Texas

Postby 358T » Mon Jun 25, 2007 4:49 pm

How much does it weigh with driver? Looks like it is coming around. What nozzle and pill are you running now?

Scott
User avatar
358T
Pro
Pro
 
Posts: 304
Joined: Mon Sep 06, 2004 7:04 pm
Location: Highland, Illinois

WEIGHT AND PILLS

Postby seefour » Mon Jun 25, 2007 6:55 pm

IT IS 3040 WITH DRIVER AND #35 PILLS WITH 094 RETURN PILL
26 DEGREES TIMMING- HEADS MILLED TO 52.5 COMBUSTION CHAMBER SIZE.

MIKE S
Do it right the first time
seefour
Member
Member
 
Posts: 192
Joined: Sun Jun 17, 2007 12:10 pm
Location: Brenham Texas

Previous

Return to Engine Tech

Who is online

Users browsing this forum: 01z28auto, Bing [Bot], BirdMan, Google [Bot] and 16 guests