Carb for a 470" stroker

[scott1973]

I am looking for some carb advise for a 73 Charger.  I have a 470" stroker with a Comp Cams XE285HL-10 cam.  It's got 10.5:1, Edelbrock RPM heads with a little work, Performer RPM intake, TTI 1 7/8 headers, Comp rockers, etc.  This is for a street car and with 9 1/2" Dynamick converter.   I understand the formula is RPM x C.I divided by 3456.  I'm getting mixed reviews on choosing vacuum or mechanical secondaries.  Seems like a VS carb is more inline with my build, but I've been advised both a Street HP 750 VS and Quick Fuel SS-830 with mechanical.   Any feedback is appreciated.

Thanks,
Scott

[c00nhunterjoe]

On that build i would run an 850 cfm unit. The choice of secondary function for me would depend on the gear going along with that 9 1/2" converter. Im guessing 3500-4000 as a flash point on it with the torque you should put down. If you are running a 4.10 or better gear, mechanical secondary. 3.91 or down, vacuum

[BSB67]

I am looking for some carb advise for a 73 Charger.  I have a 470" stroker with a Comp Cams XE285HL-10 cam.  It's got 10.5:1, Edelbrock RPM heads with a little work, Performer RPM intake, TTI 1 7/8 headers, Comp rockers, etc.  This is for a street car and with 9 1/2" Dynamick converter.   I understand the formula is RPM x C.I divided by 3456.  I'm getting mixed reviews on choosing vacuum or mechanical secondaries.  Seems like a VS carb is more inline with my build, but I've been advised both a Street HP 750 VS and Quick Fuel SS-830 with mechanical.   Any feedback is appreciated.

Thanks,
Scott

My first choice would be a small venturi 950, followed by a 850.  Both DPs without a doubt.

[scott1973]

Thank you both for the feedback.  I went with a Quick Fuel SS830 DP.  We'll see how it works...

Thanks,
Scott

[XH29N0G]

The SS-830 has a smaller primary venturi and large secondary like the 850 and is very tunable. The choke is also nice.  I found an A/F gauge useful for working through the tuning.

I didn't pipe in to the earlier conversation because the others responding know much more than me and your set up is slightly different than mine (3.9 stroke 383 with a slightly smaller cam).  

[scott1973]

Thanks for the reply.  I guarantee everyone here knows more about this than me.  I'm kinda winging it.  It's been a very slow and expensive process, but I'll get there some day.

Thanks,
Scott

[BSB67]

Thank you both for the feedback.  I went with a Quick Fuel SS830 DP.  We'll see how it works...

Thanks,
Scott

I have not used this one, but on paper, this sounds like a good choice.

[XH29N0G]

Any thoughts on contacting quick fuel tech for recommendations on starting points for jets, bleeds, IIFR, etc on his combination?  My inclination would be to try, but I don't know.

By the way, I am also happy to send along how my ss-830 was set up by the folks who built my engine, but I think your engine could have different demands.

[scott1973]

Good idea.  I may give them a call Monday to see what they recommend.  I did talk to them last week and apparently they are behind in production due to a shortage of parts.  Probably on the slow boat from China.   Mine was suppose to be built Friday and ships Monday. 

Thanks,
Scott

[68charger440]

I'm running a Proform 850 with mech secondaries that Ron recommended on a real mild 500" stroker. I settled in on 72 primary and 74 secondary jetting and the a/f readings are sitting in the low to mid 13 range.  I am at mid 5000 foot altitude though.

[justcruisin]

My experience with the QF830 is that it is rich OOTB. I came down from 78 to 72 in the front, went down two jet sizes in the IFR's, swapped out the rear 50cc pump and cam for a 30cc with pink cam. This is with a 448ci and xe275hl but otherwise same as yours. With the xe285hl your requirements will be different. Run it as delivered and see what you have. Interested to know what idle vacuum you get with that cam, my guess is around 10" at 900rpm. Carb is plenty big enough on my engine with a WOT vacuum test.

[scott1973]

Thank you everyone for your input.  It will be a while before we get it running as I'm pretty busy with work and kids stuff.  I'll keep you posted on how the carb works out.