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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 10:31 am 
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You have 2 separate fuel pumps with 1 line feeding feeding each fuel pump? So then you have 2 separate fuel lines each coming to a separate regulator and each regulator feeding a separate bowel on the carb???

What is one black pump rated at??

Not saying this was right but never had any issues with it, but I had 2 Holley blue pumps all #8 lines linked together in my Vega with a BBC 468 in it and would say around 600/650 hp running 9.50's with one little Holley regulator feeding a 8896 Dominator with #6 lines from the regulator to the carb and never had an issue with that..

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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 11:23 am 
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shrinker wrote:
I see no reason why it needs a skirt on the booster if it didnt need it before in the other car.
How much power is this engine?
What fuel is it running?
To answer your air bleed question; Its possible you dont have a large enough air bleed. I would put in .028" MAB's all round and .028" emulsion bleeds all round. Id use a top bleed and a middle and a bottom and start with that setup. The emulsion air flow is actually there to lower the fuel level in the well thus creating more flow through the main jet. Without enough air flow it can run lean. The viscosity will remain high and the level in the well will remain high, both these things will reduce main jet flow. IF its setup like a stock holley it will run correctly and be rich.
Of course you needs fuel in the bowls and you need no air leaks or funny business going on in the manifold.
The plugs in the top of the blocks are meant to be down low there should be a step there to stop the plug from going too far.
You need to look at the sparkplugs.



Yes I dunno, maybe the other car with the different exh set up,and not solid lifters was not making as much power? close to 600 hp? 91 pump gas. Or maybe it was lean too! So your saying to open up the bleeds to .028, So three emulsions? Usually i only see most run 2 ? Which main jet size would u recommend then to start with that setting? Last thing i want to do is blow this bitch! ,lol.. I plan on looking at the plugs tonight, just to see how they look. I can look at the track too, but i can't throw it in neutral at the stripe, as i don't have a clean neutral in trans. I can get it stopped tho and pull one then after i get off the strip is that good enough? Oh and u also said what esel changed from other car, well like i said in a few pages back i added that screen and the car picked up, maybe it leaned it out too much too? Never used that on my grandville.

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Last edited by 74 firebird461 on Wed Sep 26, 2012 11:49 am, edited 2 times in total.

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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 11:26 am 
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Beretta wrote:
You have 2 separate fuel pumps with 1 line feeding feeding each fuel pump? So then you have 2 separate fuel lines each coming to a separate regulator and each regulator feeding a separate bowel on the carb???

What is one black pump rated at??

Not saying this was right but never had any issues with it, but I had 2 Holley blue pumps all #8 lines linked together in my Vega with a BBC 468 in it and would say around 600/650 hp running 9.50's with one little Holley regulator feeding a 8896 Dominator with #6 lines from the regulator to the carb and never had an issue with that..


Barry correct, two seperate pumps two seperate lines going to each big holley reg going to each bowl, i think their 140? This is the fuel system that was in the car was all new in 09. Fed a 1100 hp pontiac blower motor just fine into the low 9's at 150. I just didn't want to f**% with the system it was all setup and it worked for that and i didn't see any issues with running it either.

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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 5:17 pm 
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Okay so I looked at fuel pressure gauge it is stuck at 3 so its not working right obviously . I would say fuel pressure is still at 7, also I pulled two plugs today just too see how they looked, now before this jetting change they always looked clean from just normal driving, racing, whatever when i would pull one after sitting etc.. I ran this car on monday for maybe 20 minutes just to check timing with a different timing light as mine was not working right at the track that day , and just wanted to verify if it matched what i set it at that day with other light and it did was still 29 total. These plugs are dark brown!.. #1, and then i took out #8

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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 6:21 pm 
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Tip on how to take plug photos. What happens is the auto focus on cameras focuses on the background to get it to focus on the plug hold the plug in your hand with your hand wrapped around the plug so that it fills the screen then the auto focus will focus on your skin. Or you can put the plug through a hole in some cardboard and do it that way. The main thing is to get rid of the background.
The engine is not lean.
The reason why its running such a large jet and going better with it is its got the wrong fuel for the compression pressure and cam. Your over fueling it to compensate for another issue.
Chuck the WB away or calibrate it or do something with it
I would definitely run a bleed at the bottom location that will pull fuel up into the booster from as low down as possible and make the main jet fill the well faster. Then the main jet could be smaller and the atomization will be better.


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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 6:28 pm 
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shrinker wrote:
Tip on how to take plug photos. What happens is the auto focus on cameras focuses on the background to get it to focus on the plug hold the plug in your hand with your hand wrapped around the plug so that it fills the screen then the auto focus will focus on your skin. Or you can put the plug through a hole in some cardboard and do it that way. The main thing is to get rid of the background.
The engine is not lean.
The reason why its running such a large jet and going better with it is its got the wrong fuel for the compression pressure and cam. Your over fueling it to compensate for another issue.
Chuck the WB away or calibrate it or do something with it
I would definitely run a bleed at the bottom location that will pull fuel up into the booster from as low down as possible and make the main jet fill the well faster. Then the main jet could be smaller and the atomization will be better.


Yea thats my stupid phone it takes s**t pics! sorry!.. So for summary do u want me to do the 3 emulsions at .028, and bleeds .028, and what about jets? Where do u want me to start for a baseline for saturday? Do U want me square jetted? What do u mean the wrong fuel? Thanks!!

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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 6:43 pm 
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I would do my plan for the emulsions as I wrote it. Because i think you have the wrong fuel, or your over fueling and it going faster, is actually a compensation for another issue, I would start with a square jetted no power valve setup. With 98 jets and fresh plugs and do a half pass and pull a plug and read it from there.
What cranking compression does it produce?
What was the cranking pressure in the old car when it had smaller exhaust and hyd lifters?
What fuel is it running?
You havent posted enough engine details.

So just confirm this please, the main thing that has happened that can cause a change in the running of the engine is the exhaust and the lifters.


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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 7:07 pm 
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shrinker wrote:
I would do my plan for the emulsions as I wrote it. Because i think you have the wrong fuel, or your over fueling and it going faster, is actually a compensation for another issue, I would start with a square jetted no power valve setup. With 98 jets and fresh plugs and do a half pass and pull a plug and read it from there.
What cranking compression does it produce?
What was the cranking pressure in the old car when it had smaller exhaust and hyd lifters?
What fuel is it running?
You havent posted enough engine details.

So just confirm this please, the main thing that has happened that can cause a change in the running of the engine is the exhaust and the lifters.


I did post it up above a few , but is 10.7 comp, cranking psi is 175-180, runs on pure 91 octane no pinging etc same I ran last year for gas, the cranking psi with hyd lifters, not sure i checked that ever? Can't remember right now sorry. I usually just do a leak down at end of the year just to see where engine is at.
Okay so I will do what u say, will i be able to tell anythign with a new plug? don't they usually take alittle to show color? Am I putting them in here or when i get to the track?

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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 7:38 pm 
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Put the new plug in to do the run. If its rich it will color the plug a little in one half pass.3 passes is enough to fully color a plug.
You can run whatever jets you need, just always go richer before you go leaner. Always test richer first, get it?
Check idle mixture after jet changes.
Look for detonation on plugs which is tiny black dot or blisters. Use a loupe so you can distinguish between carbon flakes and actual detonation dots. I dont think there will be any but its what you have to be careful off.


We still have no idea what the cam is.
How much power does it make?
What heads and flow etc?
What cubes is the engine?

Street fuel is difficult to go racing on, its distillation temperatures are very high compared to race fuel. Street fuel has more long average carbon chain length molecules and they are low autoignition temp species. Small amounts of manifold vacuum (smaller carbys so that vaporization is optimum) can help street fuels a lot by ensuring these problematic molecules get burnt to completion on the first cycle and thus avoid free radical formations.


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 Post subject: Re: 1050 Dominator
 Post Posted: Wed Sep 26, 2012 7:45 pm 
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shrinker wrote:
Put the new plug in to do the run. If its rich it will color the plug a little in one half pass.3 passes is enough to fully color a plug.
You can run whatever jets you need, just always go richer before you go leaner. Always test richer first, get it?
Check idle mixture after jet changes.
Look for detonation on plugs which is tiny black dot or blisters. Use a loupe so you can distinguish between carbon flakes and actual detonation dots. I dont think there will be any but its what you have to be careful off.


We still have no idea what the cam is.
How much power does it make?
What heads and flow etc?
What cubes is the engine?

Street fuel is difficult to go racing on, its distillation temperatures are very high compared to race fuel. Street fuel has more long average carbon chain length molecules and they are low autoignition temp species. Small amounts of manifold vacuum (smaller carbys so that vaporization is optimum) can help street fuels a lot by ensuring these problematic molecules get burnt to completion on the first cycle and thus avoid free radical formations.



The cam is what is called the road paver by the place that did my heads SDPerformance in canada, It is made by comp its on a 112 LSA set at 108.5 ICL. It uses comps magnum high lift lobes 3115 / 3116 ,244/252. .400 lobe lift .total lift minus lash just under .600, 1.5 HS rocker arms
the heads ARE KRE heads D port ,2.11 int 1.77 exh flow 290@ 550 lift. According to some of the calc my times it shows around 580-600 hp. this engine when dynoed with a smaller hyd cam 236/245 made 559 hp 600 torque, True pontiac Engine Stroked 400, using a 4.25 stroke crank along with chevy 6.800 rods. 461 CI
I have a otoscope for the plugs

FWIW Afriend of mine runs a pontiac also, 463 CI only uses a solid roller and a carb set up by the same guy that did mine and here is where he ended up on jetting at 500 DA , specs below 3750 pd 73 lemans car.

Engine/car specs show a 68 463 stroker with KRE 341 heads, Victor intake, Comp 306 roller and 1050 Dominator. 3800 Continental convertor, 4.10 spool and 325 ET Streets. IIRC I think we were pretty similar on engine specs? alot more head flow true, but seems like alot of jet too right? 95/102

Best 60' time was 1.48
Best ET was 10.67
Best MPH was 124.55

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 Post subject: Re: 1050 Dominator
 Post Posted: Thu Sep 27, 2012 1:48 am 
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So this is 461 cubes making between 550and 580hp. 1.2 hp per cube. Thats fairly pedestrian so why is this thing acting up?
The power is what the head flow indicates so I wouldnt suspect any dramas like turbulence etc.
Its got the right compression for the ratio so nothing there.
It just leaves me thinking the carby is too big and there might be some weird thing going on with the way this guy sets them up.

If we assume that the WB is working correctly and we look at the sparkplugs we see opposite indications. This is possible if there is considerable Oxygen present in the exhaust stream.The sensor can only react gases and if we assume that the burn is incomplete when the exhaust valve opens there could be liquid state HC's and unused O2's in the stream. When the sensor is presented with this scenario it will read leaner than truth. This is why you have to do fresh plug runs and read the plugs. Advancing the cam like yours is exasperates the issues.
There needs to be much more investigation to find the optimum tune for the engine. I am familiar with engines with combinations like this and they definitely have Oxygen in the exhaust stream. I have no doubt there would be somewhere around 1.5% O2 at least. The unusual thing is that if the WB is correctly working and calibrated the amount of liquid HC to get the WB result I havent seen before. The WB's are usually not that inaccurate. So detective work is needed.


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 Post subject: Re: 1050 Dominator
 Post Posted: Thu Sep 27, 2012 5:28 am 
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shrinker wrote:
So this is 461 cubes making between 550and 580hp. 1.2 hp per cube. Thats fairly pedestrian so why is this thing acting up?
The power is what the head flow indicates so I wouldnt suspect any dramas like turbulence etc.
Its got the right compression for the ratio so nothing there.
It just leaves me thinking the carby is too big and there might be some weird thing going on with the way this guy sets them up.

If we assume that the WB is working correctly and we look at the sparkplugs we see opposite indications. This is possible if there is considerable Oxygen present in the exhaust stream.The sensor can only react gases and if we assume that the burn is incomplete when the exhaust valve opens there could be liquid state HC's and unused O2's in the stream. When the sensor is presented with this scenario it will read leaner than truth. This is why you have to do fresh plug runs and read the plugs. Advancing the cam like yours is exasperates the issues.
There needs to be much more investigation to find the optimum tune for the engine. I am familiar with engines with combinations like this and they definitely have Oxygen in the exhaust stream. I have no doubt there would be somewhere around 1.5% O2 at least. The unusual thing is that if the WB is correctly working and calibrated the amount of liquid HC to get the WB result I havent seen before. The WB's are usually not that inaccurate. So detective work is needed.



Yea When I calibrate the WB I have the sensor in the exh, but the car hasn't ran for a day or two like the book says is okay to do that way correct? Or should it be outside the exh and just hanging in free air? Also I think that is why Bo laws from BLP said that the pontiacs need a skirt cause of their intake , head design, tract etc. to get some booster signal coming into it. I will set the carb up the way say with 3 emulsions and .028 bleeds and 98 jets and put a fresh plug in for some runs, and se ewhat they say and i will watch the mph, the biggest indicator, and report back saturday night with my findings, I think I may still switch out the banjo for the skirted one too unless it picks up, but it is suppose to be 75 satruday.A far cry from what it was last sunday, but in smiliar weather with jetting and carb set previously this car was running 125 in that weather!.. Really tho what weird thing could he do we have the carb in front of us with all the info and sizes? Probably doesn't pull enough rpm to really take advantage of the carb and its size.

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 Post subject: Re: 1050 Dominator
 Post Posted: Thu Sep 27, 2012 6:03 am 
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I looked back in my notes, and the other car when i first got this carb after a bunch of tweaking etc, i was all the way up to 89/98, he setup it up at 86/91 jetting, til i drilled out those angle channels from .136 stock BLP BLOCK, to .154 then i was able to go to the jetting i ended up at here which was 86/94 , before this past weekend. Still boggles my mind that it only had a .020 rear main bleed. Generally how much do u increase/decrease for each .001 HS size?

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 Post subject: Re: 1050 Dominator
 Post Posted: Thu Sep 27, 2012 7:39 am 
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So Once again I will ask before i change this whole carb deal, does anyone think this is what is starving the motor requiring so much jet when the air got really good? I mean it picked up mph and e.t in hotter weather when i added it, but maybe that is cause it leaned it out more? I never had the WB hooked up til just this last race when the air was good. First time the car ever went 124 was when i added this, the only reason i did i didn't want to get rocks or anything in motor, otherwise i always ran without anything on top, just the pan is all and a bracket holding the pan to the air cleaner stud. I watched all summer as more people fell off in the hotter weather when i did not thinking i was picking up power when in reality i was probably just leaner in the hotter weather, and when good air came back they were fast ,but i was still lean cause of it?

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 Post subject: Re: 1050 Dominator
 Post Posted: Thu Sep 27, 2012 10:46 am 
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I feel that should work fine , maybe try the old BG fuel flow test with your pumps??


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