Dommination of FI cars. - Page 5

Dick Butler · 12-17-2007, 12:51 PM

I have not run an injected car. I have seen the results of the original "weak factoring" job done from NHRA in the past for these cars. Some thought probably of getting some new blood in the racing. It worked as many went to the new cars for various reasons.
I have learned alot about the improvements from this post and knowing how it works in SS too. Injected 305 puts out the similar HP to carb models without expensive manifolds.
Seems with all these comments the discussion should move to the one thing which needs to be done to protect "everyone" with any combination who runs S or SS. Tighten up the AHFS and make it more effective in all cases. That would help everyone not just the FI versus carb but the bogus untested motors no one has seen but Bob Dennis or Bob Shaw or other creative builders.
AHFS is the only current method of adjustment. Push for making it better and all the problems can be better with time..
Good discussion of this problem...

SSDiv6 · 12-17-2007, 12:59 PM

Quote:

Originally Posted by Dick Butler

I have not run an injected car. I have seen the results of the original "weak factoring" job done from NHRA in the past for these cars. Some thought probably of getting some new blood in the racing. It worked as many went to the new cars for various reasons.
I have learned alot about the improvements from this post and knowing how it works in SS too. Injected 305 puts out the similar HP to carb models without expensive manifolds.
Seems with all these comments the discussion should move to the one thing which needs to be done to protect "everyone" with any combination who runs S or SS. Tighten up the AHFS and make it more effective in all cases. That would help everyone not just the FI versus carb but the bogus untested motors no one has seen but Bob Dennis or Bob Shaw or other creative builders.
AHFS is the only current method of adjustment. Push for making it better and all the problems can be better with time..
Good discussion of this problem...

Dick...the Olds powered/Cadillac F.I. engines that Bob Shaw and Bob Dennis are running are not bogus; they were in the books for many years. The same applies to Mark Yacavone's Mustang and Neil Smedley's Turbo Pontiacs and Buicks. Do you think because it is not a Chevy, that any other make that runs fast and under the index is bogus? It is just the fact that there are many racers that take the challenge to build cars that others are not willing to.

Bernie Cunningham · 12-17-2007, 01:11 PM

Evan,
Thankyou very much for your input on this thread, very well done, I'm glad you did the typing ! Now all we need is for the whiners to be able to READ and UNDERSTAND the contents, (hopefully a few times to digest it).

Grouping all of the "FI" cars together (all having the same outstanding performance) is really silly too and most FI combos will only run really well in outstanding conditions becauase of the small throttle bodies. Also worth mentioning is that most are 'batch fire' systems with a single coil, fuel injects when the valve is closed, how is that so "dominating". Yes it's possible to individually cylinder time these, but, so can a carb combo! As you stated, only mutli-pak coil systems can use the very expensive and time consuming sequential system for individual cylinder tuning.

I can't wait to hear the outcry when the newest batch of FI cars hit the track in '09.

Rich Biebel · 12-17-2007, 01:27 PM

What Bernie just said is exactly correct. My LT-1 with it's puny throttle body ran well when it was cool out but fell off dramatically in hot weather. I changed my fuel map constantly and tried various setups and was using some feedback trying to get it better. I was able to get it more dialable and consistant but it was also slower. It was frustrating to say the least! I should have paid way more attention to the short converstion I had with Dan Fletcher a few years ago......right before he changed from a EFI powered car to a BB carbureted Camaro.......He seems to have done quite well with an old school combo.....YA THINK!

Dick Butler · 12-17-2007, 02:30 PM

Definition of Bogus "factored" motors : motors which have inadvertantly been overlooked when the factoring was done. 400 chevy, 350 FI chevy, 305 FI chevy are at the top of the list. I find no fault with motors FOUND in the books for years. They exist but Bogus in the sense they are in some cases very much under rated and therefore initially a Killer combination. Many very intelligent racers use this method of qualifying high on the ladder. I am not referring to motors which are paper combinations....Thats another problem...Which would also be corrected by tight AHFS.

Jack Matyas · 12-17-2007, 02:56 PM

Dave--Could't get back to you yesterday as the Nor ' Easter that hit the East Coast knocked out our power.First of all I have never intentionally raced at 200-300 LBS. heavy to slow my car down--EVER !!

As for my "Meds"--the problem if there is one is that i'm back on some of them and it clouds my thinking.

Although I'm a member of the 1000' club --I'm neither a charter member nor Alumni .

As for the" FI Police"--I have no idea who exactly "they" are--please inform me ASAP.

Happy Holidays......

Evan -- Give it up pal , you're trying very hard to educate some of these guys on FI issues and they simply don't want to learn . There are those out there who think racing an LS1 is a bowl of cherries and don't realize how hard or costly it really is. From a cost standpoint a racer could probably build 2 to 3 Chevy 350/255 hp for every one LS1 engine he builds and do it in 1/3rd the time .

Bruce Witherspoon · 12-17-2007, 10:31 PM

Quote:

Originally Posted by Bernie Cunningham

Evan,
Thankyou very much for your input on this thread, very well done, I'm glad you did the typing ! Now all we need is for the whiners to be able to READ and UNDERSTAND the contents, (hopefully a few times to digest it).

Grouping all of the "FI" cars together (all having the same outstanding performance) is really silly too and most FI combos will only run really well in outstanding conditions becauase of the small throttle bodies. Also worth mentioning is that most are 'batch fire' systems with a single coil, fuel injects when the valve is closed, how is that so "dominating". Yes it's possible to individually cylinder time these, but, so can a carb combo! As you stated, only mutli-pak coil systems can use the very expensive and time consuming sequential system for individual cylinder tuning.

I can't wait to hear the outcry when the newest batch of FI cars hit the track in '09.

Bernie,

You don't need individual coils per cylinder to run an engine sequentially. All you need is the ability to know cam position relative to crank position. The LT1 has always been capable of running sequential, thus individual cylinder tuning

LNorton · 12-17-2007, 11:43 PM

Quote:

Originally Posted by Bruce Witherspoon

Bernie,

You don't need individual coils per cylinder to run an engine sequentially. All you need is the ability to know cam position relative to crank position. The LT1 has always been capable of running sequential, thus individual cylinder tuning

Also, you can tune individual cylinders with the factory computer...

Gale Forse · 12-18-2007, 02:39 AM

How can you guys ever think that FI cars will not domminate? Last time I was starting A fire one gallon of gas made alot bigger fire than just one half gallon and with unlimted injector size you can put in as much fuel as the pump will let you. Tranlation bigger explostion and more power. No rocket sience here just plain good sence.

Evan Smith · 12-18-2007, 08:29 AM

Mr. Weak Forse,

I don't mean to be rude, but I seriously reccomend a trip to Borders or Barnes and Noble this holiday season. Your gale force is a weak breeze at best and I am feeling quite a bit of hot air. On your trip, pick up one of the many books on internal combustion and educate yourself, and please get a dictionary for your spelling. You have made but one correct statement so far, more gas will make more power. But it will only do so if you can supply more air and if the engine maintains the proper a/f ratio. Fuel in the internal combustion engine burns (it does not explode, Top Fuel cars explode). Furthermore, the mixture must burn rapidly and at the precise time needed to complete combustion, thus releasing heat energy from the fuel in order to get the necessary rise in cylinder pressure. This is needed to apply maximum pressure on the piston when it is about 7-14 degrees past TDC. Burning the mixture before this time (often results in detonation) or after it (rich condition with elevated EGTs) will have little to no effect on MBT (maximum brake torque). In lay terms it means more fuel doesn't mean more HP for you, EFI or otherwise!

This is one reason larger displacement engines make more power than smaller ones. They flow more air so more fuel can be burned while maintaining the proper a/f ratio. Proper a/f ratio in just about every naturally aspitated engine is about 12.7-13.3:1. You can burn more fuel with a smaller engine if you provide the airflow to match. This requires forced induction, nitrous, or any combination of larger cams, larger induction, more compression, stiffer valvesprings (for the larger cams) and/or increased rpm.

A carburetor dictates its own flow of fuel due to a pressure drop in the venturi, which draws fuel from the fuel bowl, into the boosters, thus causing it to shear of into tiny little particles (read: atomization) where it is then deliverd to the ports. Over jetting will result in a rich mixture and a loss of power, just like with EFI. I'm quite sure you could create a situation where the engine has way too much fuel with EFI in easier fashion than with a carb, but the poor drivability and loss of power would be the same.

You can throw all the fuel you want (which I recommend you try with your Hot Wheels car) at any engine, but it is likely you will see a huge loss in torque and hp, not to mention MPG, which will be a concern to racers as gas prices go up.

Lastly, put down the gasoline.

Evan

12-17-2007, 12:51 PM	#41
Dick Butler VIP Member Join Date: Oct 2002 Location: Richmond Indiana Posts: 1,197 Likes: 5 Liked 32 Times in 19 Posts	Re: Dommination of FI cars. I have not run an injected car. I have seen the results of the original "weak factoring" job done from NHRA in the past for these cars. Some thought probably of getting some new blood in the racing. It worked as many went to the new cars for various reasons. I have learned alot about the improvements from this post and knowing how it works in SS too. Injected 305 puts out the similar HP to carb models without expensive manifolds. Seems with all these comments the discussion should move to the one thing which needs to be done to protect "everyone" with any combination who runs S or SS. Tighten up the AHFS and make it more effective in all cases. That would help everyone not just the FI versus carb but the bogus untested motors no one has seen but Bob Dennis or Bob Shaw or other creative builders. AHFS is the only current method of adjustment. Push for making it better and all the problems can be better with time.. Good discussion of this problem...

12-17-2007, 01:11 PM	#43
Bernie Cunningham Senior Member Join Date: Jun 2002 Location: Southern California Posts: 558 Likes: 25 Liked 53 Times in 17 Posts	Re: Dommination of FI cars. Evan, Thankyou very much for your input on this thread, very well done, I'm glad you did the typing ! Now all we need is for the whiners to be able to READ and UNDERSTAND the contents, (hopefully a few times to digest it). Grouping all of the "FI" cars together (all having the same outstanding performance) is really silly too and most FI combos will only run really well in outstanding conditions becauase of the small throttle bodies. Also worth mentioning is that most are 'batch fire' systems with a single coil, fuel injects when the valve is closed, how is that so "dominating". Yes it's possible to individually cylinder time these, but, so can a carb combo! As you stated, only mutli-pak coil systems can use the very expensive and time consuming sequential system for individual cylinder tuning. I can't wait to hear the outcry when the newest batch of FI cars hit the track in '09. __________________ Bernie Cunningham 7053 STK Last edited by Bernie Cunningham; 12-17-2007 at 02:02 PM.

12-17-2007, 01:27 PM	#44
Rich Biebel VIP Member Join Date: Jun 2007 Location: Northern New Jersey suburbs Posts: 2,275 Likes: 25 Liked 510 Times in 200 Posts	Re: Dommination of FI cars. What Bernie just said is exactly correct. My LT-1 with it's puny throttle body ran well when it was cool out but fell off dramatically in hot weather. I changed my fuel map constantly and tried various setups and was using some feedback trying to get it better. I was able to get it more dialable and consistant but it was also slower. It was frustrating to say the least! I should have paid way more attention to the short converstion I had with Dan Fletcher a few years ago......right before he changed from a EFI powered car to a BB carbureted Camaro.......He seems to have done quite well with an old school combo.....YA THINK! __________________ Rich Biebel S/C 1479

12-17-2007, 02:30 PM	#45
Dick Butler VIP Member Join Date: Oct 2002 Location: Richmond Indiana Posts: 1,197 Likes: 5 Liked 32 Times in 19 Posts	Re: Dommination of FI cars. Definition of Bogus "factored" motors : motors which have inadvertantly been overlooked when the factoring was done. 400 chevy, 350 FI chevy, 305 FI chevy are at the top of the list. I find no fault with motors FOUND in the books for years. They exist but Bogus in the sense they are in some cases very much under rated and therefore initially a Killer combination. Many very intelligent racers use this method of qualifying high on the ladder. I am not referring to motors which are paper combinations....Thats another problem...Which would also be corrected by tight AHFS.

12-17-2007, 02:56 PM	#46
Jack Matyas Live Reporter Join Date: Nov 2001 Location: Bethlehem , PA -Christmas City , USA Posts: 4,849 Likes: 340 Liked 1,667 Times in 340 Posts	Re: Dommination of FI cars. Dave--Could't get back to you yesterday as the Nor ' Easter that hit the East Coast knocked out our power.First of all I have never intentionally raced at 200-300 LBS. heavy to slow my car down--EVER !! As for my "Meds"--the problem if there is one is that i'm back on some of them and it clouds my thinking. Although I'm a member of the 1000' club --I'm neither a charter member nor Alumni . As for the" FI Police"--I have no idea who exactly "they" are--please inform me ASAP. Happy Holidays...... Evan -- Give it up pal , you're trying very hard to educate some of these guys on FI issues and they simply don't want to learn . There are those out there who think racing an LS1 is a bowl of cherries and don't realize how hard or costly it really is. From a cost standpoint a racer could probably build 2 to 3 Chevy 350/255 hp for every one LS1 engine he builds and do it in 1/3rd the time . __________________ Jack Matyas 1547 FS/C 2015 Camaro COPO # 62- 2012 Camaro Convertible COPO

12-18-2007, 02:39 AM	#49
Gale Forse Junior Member Join Date: Dec 2007 Posts: 7 Likes: 0 Liked 0 Times in 0 Posts	Re: Dommination of FI cars. How can you guys ever think that FI cars will not domminate? Last time I was starting A fire one gallon of gas made alot bigger fire than just one half gallon and with unlimted injector size you can put in as much fuel as the pump will let you. Tranlation bigger explostion and more power. No rocket sience here just plain good sence.

12-18-2007, 08:29 AM	#50
Evan Smith Member Join Date: Nov 2001 Location: Tampa Posts: 403 Likes: 4 Liked 94 Times in 4 Posts	Re: Dommination of FI cars. Mr. Weak Forse, I don't mean to be rude, but I seriously reccomend a trip to Borders or Barnes and Noble this holiday season. Your gale force is a weak breeze at best and I am feeling quite a bit of hot air. On your trip, pick up one of the many books on internal combustion and educate yourself, and please get a dictionary for your spelling. You have made but one correct statement so far, more gas will make more power. But it will only do so if you can supply more air and if the engine maintains the proper a/f ratio. Fuel in the internal combustion engine burns (it does not explode, Top Fuel cars explode). Furthermore, the mixture must burn rapidly and at the precise time needed to complete combustion, thus releasing heat energy from the fuel in order to get the necessary rise in cylinder pressure. This is needed to apply maximum pressure on the piston when it is about 7-14 degrees past TDC. Burning the mixture before this time (often results in detonation) or after it (rich condition with elevated EGTs) will have little to no effect on MBT (maximum brake torque). In lay terms it means more fuel doesn't mean more HP for you, EFI or otherwise! This is one reason larger displacement engines make more power than smaller ones. They flow more air so more fuel can be burned while maintaining the proper a/f ratio. Proper a/f ratio in just about every naturally aspitated engine is about 12.7-13.3:1. You can burn more fuel with a smaller engine if you provide the airflow to match. This requires forced induction, nitrous, or any combination of larger cams, larger induction, more compression, stiffer valvesprings (for the larger cams) and/or increased rpm. A carburetor dictates its own flow of fuel due to a pressure drop in the venturi, which draws fuel from the fuel bowl, into the boosters, thus causing it to shear of into tiny little particles (read: atomization) where it is then deliverd to the ports. Over jetting will result in a rich mixture and a loss of power, just like with EFI. I'm quite sure you could create a situation where the engine has way too much fuel with EFI in easier fashion than with a carb, but the poor drivability and loss of power would be the same. You can throw all the fuel you want (which I recommend you try with your Hot Wheels car) at any engine, but it is likely you will see a huge loss in torque and hp, not to mention MPG, which will be a concern to racers as gas prices go up. Lastly, put down the gasoline. Evan __________________ Evan Smith 1798 STK Last edited by Evan Smith; 12-18-2007 at 08:39 AM.