Can some tell or better yet show me the difference between a fuel washed plug and a plug that is running too lean.The reason Im asking is Im trying to tune my hyperpac motor and it seems too lean still yet even with 56 jets in the primarys.Here is the specs on my mill.
.030 over 170

comp ratio 9.3

HyperPac intake with split plenum with dutra dual front half and modified rear

8007 390 HOLLEY with 31 shooter,50 cc pump,56 jets,throttle shafts paralell to head with primarys towards engine 1 inch spacer

Comp Cams 264 installed and degreed to 106 centerline

MSD 6al with recurved dizzy,15 initial 32 total mechanical allin by 2300rpm,52 total with an 11r vacumm can.

Thats about it.The engine runs well,doesnt overheat at all,idles well at 900 rpm and has decent power and doesnt smoke at all.It doesnt smoke black .
The porcelin of the plug is completely white with no trace of black at all which leads me to beleive its lean but you think that it woul;d be pig rich with 56 jets,especiallaly on a 170.Does the HyperPAK MANIFOLD REQUIRE THat much extra fuel becuase of the volume of air or do I need to make other changes to my setup.
Any and all help is appreciated.
HyperValiant

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1960 Hyper-Pac Valiant(rolling test-bed)
1963 Valiant V2OO(Son's summer project,- he just turned 15 )
1972 Valiant 4dr(Daughter Kelly's repair in progress)
1974 Valiant (v8) daughter Kelly's work in progress

What is your elevation above sea level?
Vacuum leak?
Secondary's stop adjusted open too far causing lean condition?
For your viewing pleasure.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Engine size has little to do with carburetor main jet size. Reducing the signal to the venturi through large plenum volumes and long valve open duration will require larger main jets. Is that carb spacer divided like the intake?

Modern gasoline does not color the plugs unless very rich. You can still read the plugs, but not by color. Wideband O2 sensors are your friends. Otherwise you need to adjust the carb by ET.

With your combination I would have advanced the cam more and gone with a wider lobe centerline. 170s behave differently as the cylinders are much smaller. This affects the optimum overlap and lobe centerline. I hope you have larger valves and a ported head.

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Joshua

what is the plug heat range, maybe they are too hot and not letting any coloring ? when i ran a 390 on my 225 10/1 motor i had 54 mains and 64`s with a metering block secondaries.

Thanks for the replys.Josh,the head is mildly ported and gasket marched,and the spacer is divided just like the plenum.I done some more testing today with better results.I had inadvertantly installed the pump cam in wrong position,I corrected that and low speed drivability is much better.I installed 58 jets and and the car moves much better(easier)on the freeway.Im gonna try a some more vacumm advance as there is no pinging now so I figure that im safe to try a little more.
I do have a set of engnbuilder valves and a erson 270 cam and a Dutra prepped oil pump but was saving that for a future 225 build.
I do plan on a wide band o2 sensor but that will have to wait a while as the real world intervenes for a bit(Daughter is entering college shortly).
I put this engine together several years ago and have learned much from the board since then,so what Im trying to do is tune this setup the best I can while building a 225 to drop in later then slip a stock cam back in the 170 and set it in my daily driver Dart.
Thanks for the help.
HyperValiant

_________________
1960 Hyper-Pac Valiant(rolling test-bed)
1963 Valiant V2OO(Son's summer project,- he just turned 15 )
1972 Valiant 4dr(Daughter Kelly's repair in progress)
1974 Valiant (v8) daughter Kelly's work in progress

Glad to know you've made progress.

Your engine combination really isn't bad at all. I've certainly done worse! The Comp cams are ground on 110° lobe centers which is just slightly narrow for a stock valve size 170, but that just degrades the idle a little bit. The power won't suffer much if at all. Advancing the cam 4° would bring in more low speed torque, but since it's all together I say drive and enjoy.

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Joshua

Joshie,thanks for the replys,I used the offset bushing approach to degree my cam,so it wouldnt be to hard to pull the front off and drop in another bushing.Your correct about the idle ,it idles fairly smooth but only pulls at the most 15.5 inchs of vacumm.Tomorrow is tune day and plan on getting some miles on her,only has about a hundred real world miles on her so far.I will post back with the results.
HyperValiant

_________________
1960 Hyper-Pac Valiant(rolling test-bed)
1963 Valiant V2OO(Son's summer project,- he just turned 15 )
1972 Valiant 4dr(Daughter Kelly's repair in progress)
1974 Valiant (v8) daughter Kelly's work in progress

That's kind of low for that camshaft...need to get some advance on it, or rework your timing...

????

-D.Idiot

Yeah, but it's only a 170.

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Joshua

Went out testing today and yesterday and started with the combo above,ended up with 60 jets, installed blue pump cam, 17 initial timing,33 total mechanical,but backed off the vacummm advance 2.5 turns and seems to run much better on the freeway,sweet spot is 2600 rpm to 3300 rpm but starts sounding lean after that(loud and "dry") but will rev to 4000 rpm before it stops pulling(this is in od on the freeway).In 1st gear it pulls hard to 5500 rpm(4.56 gears,26 inch tall tires),and may possibly rev higher but havnt been that brave yet.BTW,I am running a quick change secondary with a plain spring.I should also note that freeway driving gives 10to 15 inchs of vacumm at 65-70 mph and secondary road driving is 15 to 18 inchs of vacumm.If more info is needed let me know.
HyperValiant

_________________
1960 Hyper-Pac Valiant(rolling test-bed)
1963 Valiant V2OO(Son's summer project,- he just turned 15 )
1972 Valiant 4dr(Daughter Kelly's repair in progress)
1974 Valiant (v8) daughter Kelly's work in progress

it might be the secondaries are coming in lean.do you have a metering plate or block, if you have a metering plate you can drill it with wire drills to increase to fuel flow but start small.if you get a block just try more jet.

Terry,I do plan on a 4150 conversion but right now only have a plate setup.Will all secondary plates interchange?I have a ancient 450 cfm vac.sec.Hollley that might have a bigger secondary plate.I was under the impression that drilling plates was a no-no or maybe thats just drilling out the main jets.If its ok to drill I will get a set of bits and start experimenting.Also would colder plugs help anything?
HyperValiant

_________________
1960 Hyper-Pac Valiant(rolling test-bed)
1963 Valiant V2OO(Son's summer project,- he just turned 15 )
1972 Valiant 4dr(Daughter Kelly's repair in progress)
1974 Valiant (v8) daughter Kelly's work in progress

i have drill them but use a wire hand held drill set not a power drill, i found that using the main jet as a guide helps to find the drill size, as far as i know all plates are interchangable, the larger the last number means richer (-34, -39), with 9/1 comp i would use nothing hotter the a rn9y champion or it equivalant in another brand.