I think my carb is too small ??

bigaldart · Post by **bigaldart** » Wed Oct 31, 2012 10:42 pm

Bigger is better for a blower carb, what over/under drive do you run, I can work out airflow requirement from that. Blower moves same amount of air every rev. For reference we ran an 850 and then a 950 when we went straight alky. Injector flows 3,500 cfm.

Alan

mgbv8 · Post by **mgbv8** » Wed Oct 31, 2012 10:52 pm

I use an edelbrock 800 carb. I was told I should go for an 850 but this one came up dirt cheap and almost new.

Does this have the air bleeds?? Cant seem to find much about this in the edelbrock pamphlet I have?

Up to now I've been trimming afr from the nitrous system.

I'll need to check the teeth on the pulleys so i know the crank to blower pulley ratio when I get back on the car in a few days.

sidecar · Post by **sidecar** » Thu Nov 01, 2012 5:36 am

mgbv8 wrote:I use an edelbrock 800 carb. I was told I should go for an 850 but this one came up dirt cheap and almost new.

Does this have the air bleeds?? Cant seem to find much about this in the edelbrock pamphlet I have?

Up to now I've been trimming afr from the nitrous system.

I'll need to check the teeth on the pulleys so i know the crank to blower pulley ratio when I get back on the car in a few days.

The Edelbrock carbs do have air bleeds but that are pressed into the boosters and are not really adjustable. (Unless you drill them).

Really you are stuck with changing the rods and jets in order to trim the AFR. I have found that the carb is not all that sensitive to secondary jet changes, in other words you need to change the secondaries quite a few sizes in order to change the WOT AFR. Of course this could be different on a blower engine!

kiwicar · Post by **kiwicar** » Thu Nov 01, 2012 10:15 am

Hi Perry
Have you looked in the David vizard book on inlet manifolds/ carbs? I think you still have it, if not I will dig it out at home and get it over to you. Do you have the book "street supercharging" , can't remember who it is by, but I will look that out for you, it will have something on carbs for blowers in it.
Best regrads
Mike
PS If the weather is any good I may be trying to fire up the engine again

bigaldart · Post by **bigaldart** » Thu Nov 01, 2012 7:22 pm

Street supercharging is by Pat Ganahl, mostly talks about fitting twins rather than a single so the float bowls can keep up. Vacuum under the carb is what sends it rich needs to be less than 1.5" hg at max rpm for best performance. Holleys are only designed to work at that level so any more vacuum and the metering goes dead rich, even a huge air bleed won't cure it. Edelbrock will be similar I should imagine, especially with those vacuum operated secondaries.

Alan

mgbv8 · Post by **mgbv8** » Tue Dec 04, 2012 9:20 pm

I've done some sums and I should be able to max out the carb on 7 psi of boost. But if I want to run 13psi it seems I may need 930cfm to feed the engine. So I guess a 1000cfm Holley is next ??

The Weber 800 seems to be the biggest they do.

I dont want to be tempted to run nitrous under the carb to trim the afr and give the extra oxygen required. I want to max out the engine on boost only for 2013.

kiwicar · Post by **kiwicar** » Wed Dec 05, 2012 10:29 am

Hi Perry
There is a 1050 dominator on eurodragster for £100 been up a while, 24th of november, but he may still be selling it, the advert underneath the CS1 Lenco.
Best regards
Mike

mgbv8 · Post by **mgbv8** » Wed Dec 05, 2012 1:45 pm

Thanks Mike!
I just called and he still has it for sale. I'm calling him back later to arrange the purchase.

perry

kiwicar · Post by **kiwicar** » Wed Dec 05, 2012 2:04 pm

Hi Perry
good news, well I hope so, just have to get all the stuff for setting up a Holley now . . .
Best regards
Mike

r2d2hp · Post by **r2d2hp** » Wed Dec 05, 2012 2:24 pm

Mike, now look what you have done. Bet were back to the rollers after Christmas

Post by **Coops** » Wed Dec 05, 2012 2:34 pm

r2d2hp wrote:Mike, now look what you have done. Bet were back to the rollers after Christmas

mgbv8 · Post by **mgbv8** » Wed Dec 05, 2012 2:43 pm

I've got a big kit for Holleys. But its for the 600's I have. Hopefully things like jets, squirters, pumps etc will be the same??

I'm paying the guy online later on this evening so I should have the carb by the weekend. This carb weighs 16lbs ??

I've found an adaptor plate on ebay but now I can find the link. It was about £55 from the USA.

mgbv8 · Post by **mgbv8** » Wed Dec 05, 2012 2:45 pm

Found a cheaper one

http://www.ebay.co.uk/itm/Holley-Carb-A ... 415fff9640

kiwicar · Post by **kiwicar** » Wed Dec 05, 2012 2:49 pm

Hi
You two might be but I am on holiday from the 26th to the 8th january And I am pretty sure I won't be popping back for the odd dyno run

Best regards
Mike

r2d2hp · Post by **r2d2hp** » Wed Dec 05, 2012 3:30 pm

Did Pel authorise your holiday request