Carb choice

[Petrol Head]

Hi Guys

I am upgrading my 454's to try to get close to the 540HP mark as quoted in the edelbrock dyno

http://www.edelbrock.com/automotive/7161pp.html

The spec calls for 750 cfm carbs.

I have 600 holley's right now, so they have to go.

I would like you're advice on what you think I should buy the holley or the edelbrock?


TIA
Steve

[Jon Fuller]

What manifolds/exhausts are you running?

[Petrol Head]

IN's as per package, performer RPM

EX's are stainless marine.

[Jon Fuller]

To really get anything out your cam you're gonna need true 'seperate runner' headers, or close to it.
The spec sheet quotes the normal 2 1/8" dia x 32" headers

[Petrol Head]

Thanks for that Jon

I cant do everything by their book for sure.:cry:

Which would you use.

Holley's or the Edelbrock's?

[Jon Fuller]

I think I'm right in saying that a the edelbrock's are only re-badged holleys or Carter quadrajets, so i'd go for holley's.

There used to be some really nice cast ali manifolds that had long separate runners, originally by a indipendant exhaust manufacturer, they are now marketed by an engine builder, Keith Eickert I think, or could be Paul Pfaff.

They were also fitted to the 600hp Volvo motor

[Jon Fuller]

It is KE,

Here they are

[Jon Fuller]

cutaway

[Petrol Head]

I'll have to look out for those pipes on the volvo stand. This year.

I havent had the risers off yet but Tony and Cronky say these have sperated runners up to the riser joint. They have that cast ally design too. I cant understand why the dont rot off, but stainless hadnt had one back in ten years??

I have Gil butterfly tips to work externally into the transom some time and I guess the best time to redo the pipes is when I rework the transom for these.

I heard that the Edelbrocks are carters.

I didnt know they used holleys too.

I was supprised to find that just fitting Stub stacks and freeflow arrestors was enough to put the 600 holleys out of tune. I dont see much point in retuning these things when they are already at the extreme of their operational range.

[Petrol Head]

Hmmmm. I like them !

[Jon Fuller]

I personally don't like Carters, so would have holleys every time, with vacume secondaries, not the manual type

[Petrol Head]

The blocks ,standard two bolts.

Reversion hasnt been a problem to date. I think if anything the current valve sizes are probably restricting this.

It might become a problem as the gas flow and C/R improve though.

[Jon Fuller]

Are you already using the #7162 cam then?

[Petrol Head]

Originally posted by Matt
Wouldn't it be cheaper, and less hassle, to put a pair of blowers on?

This is not hassle to me. I enjoy it.

Simply bolting on the heads that matched the manifolds and cams already in place was the original plan. No hard and fast aims.

A bit of fun

Then I saw that flippin Graph!

[Petrol Head]

Originally posted by jon fuller
Are you already using the #7162 cam then?

Cant say for sure I havent read the numbers on them meself.

Tony told me he bought and fitted the performer rpm inlets with matching cams.

The manifolds are marine performer RPM's.

[Petrol Head]

Originally posted by jon fuller
I personally don't like Carters, so would have holleys every time, with vacume secondaries, not the manual type

why whould you go for vacuum secondaries jon??

[Jon Fuller]

Much less likely to get flat spots.
If you open the taps real quick with manual jobbies, and the motors are at low rpm's, it may well have trouble 'carburating' till the revs are up, resulting in a nice big flop in the power, vacume secondaries wont let that happen. just MHO

[Petrol Head]

Thanks for that.

I would like the Vac secs too . I would prefer them to function with load rather than just follow track the primaries.

I ask because I am anticipating a problem .

I think the bigger valves and higher compression ratios bring with them less idle vacuum and a generally a more unstable idle?

[hutchy]

here,s 4 edelbrocks,carters,webers,federal mogel call them wot you want,they are not edel brock quadrajet spread bores .
these are750 cfm marine carbs and work well on these 700hp blower motors with no flat spots from 850rpm-5250 at 6psi boost.they also give better fuel returns than holleys ,tried both

[Petrol Head]

Originally posted by hutchy
tried both

Thanks for that, hve you run them on motors without blowers too?

I imagine you have a good idle vacuum with that setup!

Very nice.


More pictures please!


steve

[Petrol Head]

Im a bit confused by your post there.

Just who's marine carbs are they?

[hutchy]

edelbrock performer,still same as carter, federal mogul,at end of day their all webers.

[Petrol Head]

Thanks.

Do you find there are any real differences/ benefits in getting them apart ?

No one really slags them off, and everyone who has used them says the jet setup was right ,straight out of the box.

Was that the same with you?

[Jon Fuller]

I would NOT want to feed those babies!
Steve, have you become an international drug smuggler or summat? Feck, it makes me feel weak just thinking about it.

PS, hows ya new mate?

[Petrol Head]

No Jon

I am an international man of misery...mystery even.

[Jon Fuller]

Sorry Steve (Stamper) I was talking to Steve Hutchins (Hutchy) refering to his guzzlers! sorry for the confusion

[Petrol Head]

Thats the last time I mess with someones elses Avatar!:well:

[hutchy]

carbs do come ready for unblown motors,most work can be done without stripping carb.apart from second mains.full set rods ,springs,jets only about £20.00.we use model1410 manual choke but remove chokes and machine choke tower off to improve flow.

[Petrol Head]

Thanks for that.

Edelbrock are trying very hard with these.

I shall look further.

Did you source them over here?

[Petrol Head]

Originally posted by jon fuller
It is KE,

Here they are

KEP-K80401000
Keith Eickert Cast Aluminum Exhaust Headers
$3,663.50 plus shipping and duty, per engine.:cry:

Dont often see them in the january sales either.

[Petrol Head]

Them they're cams, not my choice.

Been in the bert since beforeI bawt it.

Zorst pipe picky page dont load?

[Petrol Head]

I wish it was as simple as coal and steam.

Dunno which of those pipes you were thinking of.

Have got these on boat.

http://www.stainlessmarine.com/bigblockb.html

[Petrol Head]

Has a moderator eaten my post?

[Petrol Head]

OK whatever..

I wasnt set on changing them at all.

Only if the reversion occurs after the head change. And that was only becasue the KE's would solve it.

They are no longer an option. IF it occurs, I'll pull the cams rather than feed K.E. and fit rollerones with a tamer profile.

I wont need the fuel pump lobe so I think I could use the Gen 5 ones ?