delcowizzid
on holiday
draw through carb setup there should be no need for raising fuel pressure you have no boost to overcome
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VK turbo
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hiy_po
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yeah but an SU is made to run at 4psi max fuel pressure, so when you are feeding the fuel in threw a 0.125 thou hole at 4psi and drawing it out threw a main jet at 0.100 thou by a turbo boosting at 10 psi. How are you going to stop the fuel bowl levels from dropping and leaning out the mixtures as they do??? I think I have solved the problem but if you have a better way that doesnt involve modding holley fuel bowls to supply a larger volume. I am all ears.
delcowizzid
on holiday
bigger float needle and seat 0.156 or bigger if you cant find one to buy there is a trick or 2 involving a ball bearing attached to the needle and drilled seat to really increase your flow 
hiy_po
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Yes you are on the money. My original needle and seat size was 0.040 and it made 175rwhp. The first change I made was to the 0.125 needle and seat and what do you know 235rwhp, so it had occurred to me going larger again would do the job nicely, I would rather get a larger volume than just add more pressure. The needle and seat I am using now has a ball bearing and spring setup, I have had a look at it with making it larger in mind but I really dont think it would be as easy as just drill it out. The ball bearing is so close already to the size of the hole that if I made it any bigger it would just fall out. If you know where to get these 0.156 needles and seats feel free to share the info. I do know I am trying to get something the wrong way as boost referencing is to overcome the higher pressures in the float chambers under blow threw conditions but it does seem to me that the way I am using it can help my lean at upper boost condition. The time I will see if it works or not is on the dyno. The old 0.040 needle setup was the older style with a Teflon tipped needle. I may drag them back out and see if they can be opened up to a bigger size but the needle may just dissapear too far down the tube so I wont know until I give it a try. But if you can post up were to get the bigger bore ones I will grab them.
delcowizzid
on holiday
dont know where you would get a 0.157 nowdays been a while since i bought parts for an SU
hiy_po
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VK 202 dyno run
Well I took it to the Dyno again today and got some good and some bad. Seems my ideas for the fuel system work as I hoped they would And I have a setup that although is very spikey it stays rich under boost. I think I have around 300rwhp but cant prove it with a dyno read out. My clutch just cant keep up with the motor and slipps as it pushes past 8psi boost. It is a severe duty RPM unit that was supposedly suitable for a turbo charged engine upto 350 hp but I see they mean flywheel horses because there is no way its holding on with mine now. So time to start clutch shopping. I dont think I am all that keen to get another clutch for the borg warner 5 speed as I have my doubts the box will hang in, so maybe time to start getting all the goodies for a supra conversion.
Anyway here is the latest sheet, 215rwhp is 20 less than before but the AR graph tells the true story and you gotta love the 217+kph it pulled, once the HP had fallen away and the clutch could get a grip again.
Well I took it to the Dyno again today and got some good and some bad. Seems my ideas for the fuel system work as I hoped they would And I have a setup that although is very spikey it stays rich under boost. I think I have around 300rwhp but cant prove it with a dyno read out. My clutch just cant keep up with the motor and slipps as it pushes past 8psi boost. It is a severe duty RPM unit that was supposedly suitable for a turbo charged engine upto 350 hp but I see they mean flywheel horses because there is no way its holding on with mine now. So time to start clutch shopping. I dont think I am all that keen to get another clutch for the borg warner 5 speed as I have my doubts the box will hang in, so maybe time to start getting all the goodies for a supra conversion.
Anyway here is the latest sheet, 215rwhp is 20 less than before but the AR graph tells the true story and you gotta love the 217+kph it pulled, once the HP had fallen away and the clutch could get a grip again.
delcowizzid
on holiday
least its not leaning out now
hiy_po
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Been a busy weekend but I have a new clutch in the old girl. Brass button puk jobby again by RPM but they reckon this one has an extra %35 clamping force from the pressure plate and the brass buttons : and I quote RPM :- will not slip. Looking forward to my next Dyno visit now and praying to the god of Holden that all this new grip doesnt kill the gearbox or diff. It is a sprung plate as well so thats a plus. A trip down to Fergys to fit my VL diff and 4wdisc brakes is the next big job.
I wasnt going to change my clutch but last week I jumped in the car to go to work and the clutch wouldnt disengage when I pressed the pedle. I thought I may have done a clutch fork but once I got it apart I found the locating dowel pin from the back of the crank had fallen out and jammed its self in between the clutch plate and flywheel. I also discovered my flywheel bolts were not loose but were not as tight as they shouldve been either so they got a retorque as well. Just hope they are not stretching and can see why people go to the trouble of drilling and retapping to 7/16 ARP flywheel bolts. If I get any strange vibratons in the future it will be on my to do list. I also think I will go the bigger bolts on any future engine builds.
My new clutch
I wasnt going to change my clutch but last week I jumped in the car to go to work and the clutch wouldnt disengage when I pressed the pedle. I thought I may have done a clutch fork but once I got it apart I found the locating dowel pin from the back of the crank had fallen out and jammed its self in between the clutch plate and flywheel. I also discovered my flywheel bolts were not loose but were not as tight as they shouldve been either so they got a retorque as well. Just hope they are not stretching and can see why people go to the trouble of drilling and retapping to 7/16 ARP flywheel bolts. If I get any strange vibratons in the future it will be on my to do list. I also think I will go the bigger bolts on any future engine builds.
My new clutch