sorry thats too small i cant read it
sorry thats too small i cant read it
hope this is better..
Have to use stnd exhauste manifold and down pipe. Cam modify after that.
Have to use 32/36
have to use stnd to pinto range..
Cheers madragon
Last edited by Dave; 27-09-2010 at 23:27.
so you have to use the 32/36 and a std inlet manifold, which means the 40 DFAV isnt any use anyway unless you want to cheat, but not only would such a cheat be very easy to spot
it means if you do win anything you wont really be winning.
the only real option you have is to raise the compression, with relatively restricted breathing as long as the engines set up right and doesnt detonate you can probably push the compression beyond the 10.5:1 CR normally considered safe maximum on cast pistons to 10.75, if you engines about 10:1 now then 0.75 more on the CR will make a noticable difference
sorry to change subject again but do you reckon the 40dfav is worth a try or do you reckon the 38 would be better for everyday then?????,
and if i was you madragon, i would just port the hell out of everything as much as i can and raise compression like graham has said, i belive you can also 5 angle the valves, but personally i'd look elsewhere for half a second like tyres or suspension, not much more could be done could be done to the engine to help with times that much i would think.
Hi. Compression is 10.5 -1 my spelling error.
I am not allowed to port anything. Thats why i use the injection head it flows slightly better.
On the carb idea if i raised the carb up by extending the manifold(tig and ally) then spaced with standard spacer will it help(more flow more fuel?)
i can modify the spindles and i could change the butterflies for thinner ones i would have to counter bore the holes for the retaining screws as i have to use stnd ones. Lastly is it worth making a air filter that works like a trumpet( poss bending the rules )
cars set up ok positive camber +negative camber ofset positve caster 3.9 locked diff
cheers madragon
Something you could do but I am not sure if it bending the rules is seal up a standard airbox and run the air inlet from a point of high pressure on the car. One location of the would be the the base of the windscreen or somewhere on the front of the car. THis would act somwhat like a turbo forcing air into the engine and would also help by providing cold air rather than the hot under bonnet air.
What modifications can you make to the exhaust manifold and system as there could be a lot to gain by modifying that.
Regards
Tom
[QUOTE]
On the carb idea if i raised the carb up by extending the manifold(tig and ally) then spaced with standard spacer will it help(more flow more fuel?)
i can modify the spindles and i could change the butterflies for thinner ones i would have to counter bore the holes for the retaining screws as i have to use stnd ones. Lastly is it worth making a air filter that works like a trumpet( poss bending the rules )
/QUOTE]
but all of thats cheating!!!!!!!!!!!!
[QUOTE]Hi. Compression is 10.5 -1 my spelling error.
I am not allowed to port anything. Thats why i use the injection head it flows slightly better./QUOTE]
then go a bit more on the compression, go to 10.75,
which is all going way off topic on this thread cos none of the carb mods in this thread can be done within the rules
well sticking to the thread, what carb do i use so i know what carb to modify so i can get some rolling road results on this thread. do i use my 40dfav or do i buy a 38dgas.
Last edited by caprimentle; 06-05-2010 at 22:03.
ultimately power is the name of the game here so modify the 40 DFAV, but make sure you also port the manifold to make the most of the carb
thanks .. just looking for a mod to the carb that isnt cheating... back to the drawing board
llike i say i'll definately port the manifold but will it become undrivable on the road and have catastrophic affects on the fuel gage compaired to the 38 dgas, coz the car will still be everyday, and i dont want fuel economy and drivability to suffer so much more compaired to the 38 just for the sake of an extra 5-10bhp or so. i know nothing of these 40dfav's or mechanical power valves so i do appologise if these questions are irritating, its my last one i swear then i'll leave you alone till the next problem
i've never used a 40 DFAV on a pinto, but have used it on a 2.0 fiat twin cam engine, it worked very well
unless your engines heavily modified i doubt the DFAV would make 10bhp more than the DGAS
Last edited by SidewaysMk1; 30-06-2010 at 22:49.
1973 mk1 escort
1982 Toyota corolla ke70
1988 mk4 escort
I finally got around to putting the modified 38 DGAS on the bench today
The picture shows the actual depression the reading was taken is on the main screen and the little box in the corner is the equivalent flow at 25" - so I could take a comparison to the flows in Vizards SOHC book
The head is coming off the SOHC in the Ginetta in the next week or so for some head mods so I will drop the DGAV on there as well to test it.
Last edited by Darkspeed; 18-07-2010 at 19:07.
Oooooppps - serves me right for being so lazy and optimistic - I put the DGAV on and it flowed 302CFM - Not exactly right.... So I checked the calibration on the bench and it was way out - then checked the logs and the last time I used i was 6 months back!
So I did what I should have done and calibrated the bench and then ran the tests
32/36 DGAV - 260CFM - bit shy of what Vizard obtained but there or there abouts
38 DGAS - 295CFM
A flow difference of just over 13%
The only difference between the two carbs are the butterfly diameters which is why the difference is not that marked It would be interesting to find the figures for the stock carbs
The difference between the start and the finish of Vizards mods on the DGAV was just shy of 17% for a large choke size increase so an additional 13% is very good for the DGAS
Making a comparison between the stock DGAV at 227 and a fully modded DGAS at 295 is a 30% increase in flow this also ties in with the flow figures on the 40DFI at 330 CFM
I've got a highly modded 32/36DGAV here, I'd be very interested to see what it flows. I'm not all that far away from you so maybe I could pop over one day?
http://escort.accelerator.org
1968 MK1 Escort 1300GT
1969 'Big Wing' MK1 Escort
1972 MK3 Cortina 1600XL
1984 Sierra XR4i
And other junk I don't like to talk about!
You would be more than welcome drop me a PM
Will do
http://escort.accelerator.org
1968 MK1 Escort 1300GT
1969 'Big Wing' MK1 Escort
1972 MK3 Cortina 1600XL
1984 Sierra XR4i
And other junk I don't like to talk about!
Hi Graham. I'm quite delayed with my question, and also please excuse me for my poor knowledge of the english language. So, my question is: There is an improvement by adding spacers under de carburettor, but "mainly because the carburettor appear bigger". What do you mean by saying "the carburtettor appear bigger" ? Is that related with the carb improvement ? Sorry for my question, and look forward to you kind answer. Best regards.
Eduardo
HI Graham,
Sorry for my delayed question and for my poor understanding of the english language. My question is: what do you mean when you say improvements by adding spacers. . . . . mainly "the carb appers bigger" What that it means, I get a bigger cargurettor thus better performance ? Sorry for my question, and look forward to your kind reply.
Best regards,
Eduardo
Hi, this is a message to Graham Bahr,
Graham, I have a 1700 x-flow with a 285 piper cam kit and stage 2, (big valves), Vulcain Eng. head in my MK II. My carb is a 32/36 and since I put it to the engine it has the choke butterflies removed. Now, I have a question. In one of your posts you say add spacers to the carb for improvement. I'm doing this, and I understand I will give more speed to the mixture, but what I don't get is the meaning of "mainly the carb appears bigger". I'm sorry for my poor understanding of the english language, but please be kind enough and clarify to me this point.
All my best, and look forward to your kind reply,
Eduardo
if you have a carb which is restricting the engines powerout often adding some spacers under the carb will give a little more power
I carried out some further flow tests on the 32/36 today to compare the flows through the two chokes
Figures are at 25" and are comparative figures
32mm choke with 30mm venturi - 139 CFM
36mm choke with 30mm venturi - 158 CFM
The 36mm choke flows 15% more air than the 32mm with the same venturi.
I am assuming that this is because the shaft and butterfly create a proportionately larger restriction to flow in the 32mm diam choke than in the 36mm choke - I would have tested this but as I had screwed and glued the shafts in I did not want to disturb them.
I did a flow comparison between narrowed and standard AUX venturi and the difference in the 32 and 36mm chokes was no more than 0.5CFM - so dont waste your time on that mod.
Andrew
indded i came to teh same conclusion it didnt achive anythingI did a flow comparison between narrowed and standard AUX venturi and the difference in the 32 and 36mm chokes was no more than 0.5CFM - so dont waste your time on that mod.
Hi mates, I have this situation in this moment. My "big bore" was doing almost 100% OK with this configuration: Airs 170 - 160, Mains 150 - 155, idle 55 - 55. Now, I add one standard spacer to my 32/36 DGAV and things screwed up. Again clogged spark plugs very quickly. So I started changes in the mains. first 145 - 150, problem still there but not that quickly. second 145 - 145, that looks quite allright, but I'm scared of getting lean when I'm at WOT, since std mains for my DGAV are 140 - 140. So I came to think what happens if go all the way round and mantain my original mains at 150 - 155, but increase my Airs to 180 - 170. My thinking is that if I have more velocity by adding a spacer, well I'll rather need more air than less petrol in the mixture. These thinking make any sense at all ?
Please let me have your coments, since I'm in the process of "test and error", and I don't want holes in my pistons when I'm at WOT.
Thanks in advance for you fine cooperation.
Eduardo
Last edited by ebenech; 10-10-2010 at 15:11.
Hi, when i said added a spacer, means that now I have 2 spacers. Oh well.
what is WOT?
its not dead till it's buried!
T.I.T engineering. "Feel the power!"
WOT (Wide Open Throttle) Pedal to the metal, foot on the floor, etc etc
To finish first, you must first finish
aahhh o.k nice, been wondering what that has ment for a while lol
cant help you with your problem unfortunately but it does seem very odd, what your saying does makes sence to an extent but i have no idea to wether it will work, your best of setting it all back to normall untill someone here with more knowledge than us comes up with a logical explanation for it all
its not dead till it's buried!
T.I.T engineering. "Feel the power!"
Hi "WOT" Caprimentle, It's good that you now are awared of what WOT is, since you do it all the time. Also thank you for your advise about my jetting problem, already Graham gave me a clue to look in some other problems that might be happening to my carb.
Cheers,
Eduardo.
PS And don't forget, always WOT
Last edited by ebenech; 12-10-2010 at 11:29.
maybe you carb was leaking in air around its base and adding the second spacer helped seal the air leak????????????
i would think the idle would of been very rough for him though, and when my carb was letting in air it was making a horrible whistle, but like you say one spacer should not make such a difference.
its not dead till it's buried!
T.I.T engineering. "Feel the power!"
Hi Caprimentle, Many thanks for your reply. I'm working on my carb to see what happens.
Cheers,
Eduardo
The reason spacers under the carb work better by lifting the carb higher is because this gives the fuel a much better chance of turning the corner into the port runners and still staying in suspension with the air instead of dropping out of the air stream, air can turn a lot tighter than fuel can, fuel wants to go straight onwards instead of turning round sharp bends, fuel is a lot heavier than air
Last edited by RWD fords rule; 18-09-2011 at 17:08.
"Horsepower sells cars, torque wins races" - Enzo Ferrari
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