General Carby Questions

[gerg 10,871]

Update: no good... Pops open too sharply with the purple spring in. Will try brown next.

 

Update on the update: brown spring in and it's much better.

 

This secondary popping open thing might be a problem for others so thought I might give everyone a heads-up

[FORD_MAN 1,026]

isn't the metering block, the plug is in the top of the fuel bowl, & the $200 is for some one to fix it & basic set up

Can see the rear one that someone put some kned it on to stop it leaking. the front started leaking to.

 

[gerg 10,871]

Oh that's a non-adjustable bowl and the plugs are where the needles go. It would have been fuel pressure leaking out.

[MNTL.XD 3,831]

I found this site this morning:

 

Everything you need to know about Holleys, on video!!

 

It doesn't get much better than that!!

 

https://www.holley.com/blog/carburetor_installation_and_tuning/1/

 

There are 5 pages of videos right at the bottom of the page.

 

There is also a heap of videos down the right side of the page including:

 

- Carburetor installation and tuning/troubleshooting

- Nitrous installation

- Hose and hose end assembly

- EFI tech and more!

 

Hope it helps, i know i've learnt a bit already!

[MNTL.XD 3,831]

In relation to Greg playing with the secondary springs (on page 1) I also found this, which may be helpful to anybody else attempting this:

 

 

Cheers.

[gerg 10,871]

Yep seen those charts with opening rpm, etc. Very informative on how secondaries work, shows that even on a 350 cube engine, only the very lightest springs fully open at realistic rpms. My 302 with the 650 spread bore would fully open at about 13,000 rpm lol

[MNTL.XD 3,831]

Yep seen those charts with opening rpm, etc. Very informative on how secondaries work, shows that even on a 350 cube engine, only the very lightest springs fully open at realistic rpms. My 302 with the 650 spread bore would fully open at about 13,000 rpm lol

 

 

 

Ohhhh yeah! Gotta love the way a 302 revs! My XD has been a 302 up 'till now, i never had a tacho hooked up to it so would

 

just rev it until the valve springs screamed for me to change gear. lol. It ended up with a rattle that none of the mechanics at work

 

could pin-point so after changing a couple of sets of lifters, they told me to pull the heads back off, they looked over them and

 

couldn't see anything wrong so decided it had to be the skirt off a piston, ended up pulling the engine out and stripping it just to

 

find out it had been a bent valve the entire time!!  While the engine was apart i decided to keep the 302 rods (mainly because they

 

had been balanced) and threw a 351 crank at it. I now have a tacho but i'm thinking a rev limiter would also be beneficial this time

 

around. lol. I have also learnt not to trust mechanics.

[gerg 10,871]

Lol yeah I found a bent pushrod in mine when I had the manifold off a couple of months ago. Just smacked it with a hammer and block of wood while it was still in place, spun it by hand to check, straight as an arrow! Pretty crap though as mine's limited to only 5500.

 

I figured the bottom end on a 302C (if prepped right) could handle 8000 rpm seeing as a work colleague spins his 351C to over 7000 in a race boat with stock rods and 4MA.

 

Stock valve springs are poo in both clevos and crossys. I reckon at least 20% more seat pressure is needed for any performance upgrade. Decent pushrods too lol

[FORD_MAN 1,026]

My first time with my black ute at the drags, my auto in my was neutralizing between 2nd & 3rd,

checked the recall on my tacho after some runs and got 6800 & 7200 on my 302c which has a stock bottom end, scary.

Yeah stock valve springs are crap, my XF valve bounces around 4000.

First run you can hear a little valve bonce was the 7200rpm

 

[gerg 10,871]

At least with an auto, you don't have to worry about an exploding flywheel. Anything above 6000 in a manual needs a steel one. Sounds pretty meaty for a baby clevo

[FORD_MAN 1,026]

That was straight out the 3.5" collectors

Yeah it's alright pulls to 5500 so easy, I have top gear powerskided at the drags a few times.

[MNTL.XD 3,831]

Lol yeah I found a bent pushrod in mine when I had the manifold off a couple of months ago. Just smacked it with a hammer and block of wood while it was still in place, spun it by hand to check, straight as an arrow! Pretty crap though as mine's limited to only 5500.

 

I figured the bottom end on a 302C (if prepped right) could handle 8000 rpm seeing as a work colleague spins his 351C to over 7000 in a race boat with stock rods and 4MA.

 

Stock valve springs are poo in both clevos and crossys. I reckon at least 20% more seat pressure is needed for any performance upgrade. Decent pushrods too lol

 

 

 

Haha yeah done the same with the pushrods quite a few times, this was a bent valve, alot harder to get to. lol

 

I purposely left standard pushrods in so it had a weak link in the top end, so if something does attempt suicide,

 

more chance it will bend a pushrod first, but nope, wasn't so lucky. Then i was told standard pushrods are hardened anyway.

 

Dunno mate, dunno. The boys told me to do a skid so, being young and stupid i came out of the intersection

 

at the top of the street, got it in a straight line and pinned it, 1st, 2nd all the way through 3rd 'till it ran out of revs,

 

dropped back to second and right through third again. Being a single wheeler at the time i had passed the next side street

 

so had gone a bit more than the length of the block by the time it decided to stop wheel-spinning. lol. Poor thing. That engine

 

had only done about 400km since it's initial rebuild so i'm surprized it only bent a valve. But fk a Clevo sounds good at them revs!! 

[gerg 10,871]

There's been some discussion about fuel squirters and pullover effect, etc on another thread so i thought I'd find a more appropriate one to post this.

 

http://www.thompsonperformance.com/shop_products.html

 

These are called the "Thompson Power Blast Plate". They're designed to go on top of or underneath the squirter assembly on either a Holley or Carter-style carbies.

 

Ok the price. At US$40 I think it's bloody steep for what is basically a tiny bit of punched brass sheet. They don't even discount if you get 2 for a double pumper. I think they're priced not by how much they cost to make, but how much they think they're worth.

 

 

The idea is that the fuel comes out of the nozzle, hits the inside of the plate and the air rushing past the bottom edge causes a shearing action of the fuel as it leaves the plate, greatly improving atomisation.

 

I can see great merit in the design and it is brilliantly simple. However I do find their claims of power increases hard to believe. Throttle response yes, but not power.

 

I reckon they'd help prevent fuel pullover too, if only incidentally.

 

Anyone heard about them?

 

Sent from my CPH1607 using Tapatalk

 

 

 

 

[bear351c 10,270]

Nope, never seen them.  They a Speedway thing.??

[gerg 10,871]

Nope, never seen them.  They a Speedway thing.??

They're an anything thing, designed for street or race and all in between

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[ando76 4,354]

Yeah. Have seen them and the theory on them is very good. It definitely atomises the pump squirt better than the original Holley design. The ask is bloody steep tho. Especially for something that helps in such a small part of the carbs operation and something that could be tuned out with correct pump cam, accelerator pump nozzle size and pump cc. ....

[Thom 6,650]

I bought their edelbrock ones for my old man's a model for fathers day last year as it always had a slight stumble if you were in too high of a gear when you fed the throttle in, they definitely work and it has alot better transition wether you feed it in or mat it even if you should really change down it gear, he also seems to think it is a little better on fuel