The Dodge Challenger Message Board

I am having the Dodge Challenger R/T, chassis dynoed,(mustang), next month, I installed a complete Pro-Max "kit" on it. The kit consists of billet and hard anodized metering blocks capable of accepting Holley Jets instead of a fixed metered orfice. The rear carb baseplate is also billet and allows adjustments without removing the carb(s). Has anybody else used these before and could you inform me of the results either positive or negative,Thanx,Eddie.

Just got the call from the dyno-shop and my challenger posted 405 H.P. 420 Lb.Ft. at thr rear tyres! Yeah Baby! Time to get my credit card paid off, I am gonna need the credit for new B.F. Goodrich Tires.

That is probably around 480hp at the crank. That is very good indeed for a car with stock exhaust manifolds.

I am impressed!

Dave, Thank you for the kind compliment. I am sorry but it has a complete TTI 1 7/8 Headers into a 2 1/2 TTI x-pipe system all ceramic and thermal barrier coated. That little piece of hardware was 2300.00! That includes TTI stainless tips. I had to send the pipes off to JET-HOT and have them coated as well, as the exhaust pipes are just "aluminized" and I wanted ceramic/metal particle coating which according to the coating experts is even more resilient to corrosion than stainless. Also the thermal barrier coating inside the headers reduces underhood temps by an unbelievable 50-75% which can save paint on the engine and rubber/plastic parts in the engine bay. Here is a pic of the engine, sorry that big shaker covers a lot!

Here is an underside pic.

Another

Last one, hope this loads right?

Whoops.

airfuelEddie wrote:Dave, Thank you for the kind compliment. I am sorry but it has a complete TTI 1 7/8 Headers into a 2 1/2 TTI x-pipe system

Ooops!

Oh well. In that case it's rubbish.

Just kidding man. That is one totally cool car and will go like poop off a stick with that much power and still drive like a stocker I bet?

Love the photo of the dog.

How did you know I had to get mine put down last Friday?
God I miss that dog. She used to have a lot of fan mail when I had a web page about her. She was just 7 weeks off her 17th birthday.

I am truly sorry to hear about your baby, I hope she didnt suffer. She sounds like she lived a good long life almost 17 years, wow! I wasnt kidding about the St. Francis,(patron saint of animals), she is in heaven. 2 years ago I lost one of my Dauchshunds, I have two and a Bishon Frise that I love cause I rescued Him from abusers that put ciggs out on him. ALL my animals are loved and cared for, Hershey my choc. lab is terrific around kids and he loves pretty young girls, not too young though, are you gonna get another doggie Dave? I hope you do, it will help with the hurt but nothing can take their place, I am always sorry to hear that, I also have two birds a cat and three hamsters. Eddie.

My plan is another cheap genetically strong one like Lizzie was and I also quite fancy a Saluki or a rescued greyhound (racers have them put down when they are not fast enough).

But not for a while yet.

Yeah those breeds are really cool and its a crime that people use animals such as the magnificent greyhound and then dispose of them in unusually cruel manners, such a waste. I understand about the time "thing". I hope that the weather is good enough for another "run" before the R/T goes up for the winter. We have some scenic, long stretches of road with enough flatness and curves to entice even the magnificent Carl Fogarty around here. And this is what I am craving, if the weather is good. Its been 30-40F wet,cold, rainy,damp. Has your engine project coming along ok? I read from prior posts,(old), about your crank and bearing problems? What size is your 440, Dave? I wish I had used a 4.15 Stroke crank, but I had the engine built in 1998, and stroker cranks werent that cheap, still arent for a callies,bryant or other U.S.made crank.

I don't go with the stroker crank fashion. So mine is stock stroke and only 30thou over.

The engine would have made more torque at lower rpms with a stroker but with some loss of peak HP. Also the piston speed would increase (causing more wear/friction and stressing the rods) and the throttle response decrease.

I am old fashioned and prefer my bore to be a good bit larger than the stroke.
You ever see the stroke on a F1 engine? Very little. Hence the high rpm capability.

Changing to a solid lifter cam should give me a lot more lower rpm torque and only drop power that is past my shift point anyway.

Yes, Dave I too am old fashioned, BTW its gone full circle, Heads are key in any build anyway, and you are right on all accounts about friction/rod ratio and bottom end geometry,(we are talking about engines eh)! I do wish I had gone with a solid lifter camshaft setup, this was right before shubeck lifters came out on the open market,(700.00 approx) just for the lifters. BTW no valve lashing needed after proper install at least for the first 35k miles is what I have beeen reading and hearing! They are on backorder currently as the military is buying up all ceramic for their ammo.Im sure they could be had but it would take awhile,btw the other solids arent that bad anyway. Oh well I am elated with what I have. The Pro-Max parts I feel are an absolute MUST-HAVE for all six-pack owners trying to keep their Holleys in tune.The dyno operator at the shop called me and requested all the contact info for promax he was very impressed at how easy it was to install and tune.They are also hidden under the shaker bubble so yes its stock man!

The ProMax parts sound great. But I have my six pack tuned very nice now and I am not messing with it again if I can help it!

My six pack is from a British Jensen 440SP. They were using 6-packs on these for a few years after Chrysler stopped fitting them. Mine is one of the later ones.

The reason I know this is because there is no provision for idle mixture control in the outer carbs. They do not have the "hidden" air screws that the '69-'71 carbs had. So the center carb has to supply the idle mixture for the whole thing.

The metering block was no good for a big cam either. Very restrictive idle circuits. So I fitted a metering block from a 850 double pumper. Even then I had to drill out the idle fuel restrictions in it.

To get enough air in so it idles right I had to drill holes in all six throttle blades. This allowed the engine to idle at 800rpm with the throttle blades covering the transfer slots for good off-idle action.

I later upped the idle speed to 900rpm to get some output from the under driven alternator. But i did it by enlarging the holes in the blades a touch more.

I also had the carbs converted to manual operation by "Six Pack To Go" in order to loose that vacuum secondary hesitation. It works very well indeed.

Dave, I am impressed didnt know you were such a carb tuner! Man I sure am not. I can rebuild/restore old Holleys,Carter,bbds ect. But man, you went to great lengths to get that Jensen setup just right, also I was wondering do you have a vacuum advance port on your Holley center? I did but with the billet metering plate that pro-max offers there is no provision for VA. Not that I need or want it anyway, just curious. My cam would not allow for any vacuum advance at low speed, this would cause surging, bucking and other horrible drivability issues. My M.P. dizzy,(mallory built for chrysler, accell reportedly built some as well), is set to 34 degrees all in at 2400 rpm. Vac. Adv. plugged. Now I know who to ask for Carb Help!! 1-800-grumpy old carb tuner!!!!

You can adjust the vacuum advance in the MP dizzy. At least you can adjust the rate at which vacuum advances the timing.

I used to use the vac advance but I fixed the vac can so that it only added 11 degrees (I was aiming for 10) total. This prevents "pinking".

Vac advance only works at part throttle with the engine under load. It should not work at idle at all. This is one of the the reasons it is so important to get the primary throttle blades closed enough with a bigger cam. If they are open enough to give you vac on the timing port then the idle circuits are not working either.

The benifit of a bit of vacuum advance is better mpg and cleaner spark plugs. When you floor the throttle there is no vacuum advance so it plays no part in timing when drag racing for example.

However my new MSD dizzy has no provision for vac advance. So from now on the port from the metering block will be blocked off.

I forgot to say. My timing is usually around 34 degrees all in by 3000rpm or just over. I like around 14 degrees initial. Half the timing in by 2300rpm. the hotter the cam and higher the convertor stall the faster they seem to like to see the timing. But timing is very indivdual for an engine. You cannot apply the same rule to every one.

Yes you are right on about vac. adv at idle and the throttle blade position in reference to the idle slots in the carb body. Having an auto tranny also is another factor with the stall speed. I use a MSD dizzy in my PowerRam with the crate 380/360 and it has no vac adv either. Yes it can help with plug issues and chamber deposits ectt..I noticed very little change in fuel consumption on my truck, and I still change the champions in it every year. What plugs do you run in your R/T Dave? I have NGKs in my chally and it seems to like them. I have typically been a "champion" or Bosch man myself. I will use the NGK again. STAY AWAY from spitfire those things should be outlawed,(total junk)!!

I was using Champions, then NGKs (good), then Denso's (what Accel's are in real life and very good plugs) and now I am going to try NGKs 'Iridium' plugs because my physics tells me sparks like jumping from sharp points (and some reacers used to sharpen the center electrode on race plugs) so I think they are worth a go.

http://www.ngk.com/more_info.asp?AAIA=1078501&pid=3557

What heat range are you guys using , say in the Champion line. I am having FBO recurve my stock electronic distributor and Don says I may now experience some detonation. I have been using the stock RN9YC with a purple shaft cam and iron heads with no problems. But that was with limited total advance in the stock curve and ECU. Would a colder plug help?
Another question:

Colder in the Champion line would be a lower number?
Colder in the NGK line would be a higher number?

Let me know how those Iridiums work Dave. At 7 bucks a plug a little pricey but acceptable if the plug stays in tune longer. That iridium is very hard and has little resistance, both good properties of a conducter! Dave do they make them in 5/8 instead of 13/16 ,this will give a little bit more "header" clearance. Oh and by the way my challenger will be in an upcoming issue of MoPar Muscle Magazine. They are doing an article on six-pack tuning, the chrysler six-pack carbs and how to make more power with PRO-MAX six pack parts. Thank God they didnt ask for a pic of my mug, all that beauty and my mug would ruin everything,(think that little bald guy on the benny hill show), whew!!

Jon wrote:What heat range are you guys using , say in the Champion line. I am having FBO recurve my stock electronic distributor and Don says I may now experience some detonation. I have been using the stock RN9YC with a purple shaft cam and iron heads with no problems. But that was with limited total advance in the stock curve and ECU. Would a colder plug help?

Only change the heat range of the plug if the plug tells you it wants changing. As i said in another post the other week, The ideal timing curve is made by advancing the timing at 2000rpm, 2500, and 3000rpm under heavy load and seeing how much timing you can dial in at each rpm stage before detonation. Only then do you know what the ideal timing for YOUR engine is.

Don seems to time everything as if you are driving a light weight serious gear full race car.

I bet he said you "need" about 18 degrees initial timing as well? He usually does.

Now this is what I don't understand about Don. Why would he change your timing to make your engine detonate? he should be timing your dizzy so that you get as much timing as possible WITHOUT detonation.

That guy drives me up the wall.

You cannot "guess" what the ultimate timing curve should be for ANY given engine. Even if it is the same spec. There are too many variables.

I don't trust Don and I don't like him.

Here is an example. His UK supplier gives me a one piece six pack gasket to try. The holes for the carb bolts work but are a few mm out so they don't center and the bolts are hard up against the sides of the holes.

Also the accelerator pump lever hits the gasket.

His conclusion? Chrysler manifolds were all drilled erratically so my bolt holes in the manifold are out. He used a super dooper new one to program his CNC gasket cutter that is super dooper special for some reason I can't even remember. So either my manifold is out of whack or I am just not capable of measuring anything.

So took some photos and explaned that the holes in each carb base match the holes perfectly in the manifold. The error in his gasket is not between carbs but is between the bolts FOR each carb.

His reply. My manifold is wrong.

Again I explain and photograph the gasket against the bottom of the center carb so he can see the holes in the gasket do not quite match the holes in the carb.

His answer. He can't make mistakes. I am an idiot.

He then went on to tell me how I have tuned my carbs all wrong and that my timing is all out of whack. He has never seen my car in his life and had no idea what it has run on the strip yet he is telling me I don't have any idea how to tune my own car that I have owned for 17 years?

What an a-hole.

(Sorry for the rant. Had a couple of glasses of whiskey. )

Actually Dave is absolutely right on. There is no way you can cover all the bases with a set timing curve. Jon what do your plugs look like? If the number is lower on the champions yes its a colder plug. Have you tried Champion plugs in the 10 series a step up in heat range. If you or somebody you trust can look at the plug and tell if you have a proper burn pattern on the insulator and tip and ground strap,(all important), what size is your cam to run 18 initial, which BTW is more initial timing for the larger the cam. I HAD to run 16-18 initial in my Crate 380/360 M.P. engine just to get it to idle decent and not load up. It had the infamous 292/508 purple shaft in it with 74 degrees overlap. A pretty hairy street cam! Also JON can you post any pics of a plug? We can help you "read the burn pattern on it!!

Thanks Eddie, but, I know how to read plugs. Mine currrently look perfect. All the same color as a bonus. Just wanted to know if colder plugs reduce detonation as more juice will be forthcoming. Sent Two plugs into the shop as requested by FBO for analysis. That tells me they know something.

Dave, nice rant I have been there too. You probabaly resent my password that time. Hope you are wrong or else I am in for some major tuning hassles . If it pings bad, I am going to ask for a solution real quick. Got to give it a chance though. We Will See.

Jon, as a rule of thumb, the "hotter" the engine,(more cam, fuel, cfm or air), the colder the plug to do exactly as you described, reduce the chance for detonation. What are your planned mods? Any Nox heh, heh. If so then you must run more fuel which generally means colder plug and less timing. More cam, carb and compression also dictates the same logic. Also since you run iron heads, detonation wont "hurt" as bad as an aluminum head engine. Oh,by the way do you have a single plane intake and does your engine recieve underhood air or forced air inducton like a scoop. The reason I ask is a friend was running colder plugs in his rod and when he installed a fresh ram air kit he had better results with the stock heat range. Also remember the "colder" the plug the longer it takes to self clean. Like Dave said Jon ya gotta find that "majic" combo which your and only your engine wants, without detonation of course. Hope this helps in your tuning and future mods.

Yes Don always asks to read your plugs.

Sounds really professional dosen't it.

The short answer (if I hadn't had a couple of large 12 year old single malts last night) would have been - no. Changing the heat range of the plug will not have much effect on detonation unless it is way out. Like glowing white hot. Just suck it and see. Keep an eye on the plugs and let them do the talking.

I agree that you should give Don a chance and try it out. He does know some stuff and is a real expert in some areas. I just think most of it is based on his work on things like his 10 second 318 powered car which launches at about 7000rpm. That is a long way from a street car.

He also has a MASSIVE ego. And you all thought I was bad?

Eddie, I am running 10.5 to 1 compression with 484 lift and 284? duration hydralic cam. Edlebrock LD 340 manifold (dual plane with center divider removed), 650 double pumper holley carb. The best gas in my neighborhood is 91 octane and sometimes that claim is suspect. I set it up for 2500-6500 RPM but rarly hit the top due to past connecting rod disconnection memorys.

Yah Dave I hope he didn't set it up for a strip racer. I needed the ECU mainly and he kinda talked me into the dizzy recurve. With my luck you will probabaly get to say "I told you so". The motor runs fine now and I think it is jetted pretty well. Never a hint of pinging that what makes me think I have a little more total advance available. A couple of times however, it detonated really bad for no good reason. I think the timing weights would get stuck giving full advance at any RPM. Hopefully that should be resolved also.

Back to the heat range numbering. My experiece jetting and reading plugs with dirt bikes (using NGK spark plugs) is the higher the number the colder the plug. I heard Champions and many other mostly automotive oriented brands are opposite. Is that true?

Thanks

Yes Jon the Champions=lower number is a colder plug. That 284 Mopar cam is a great cam isnt it. Oh and if it is detonating at WOT or high RPM I personally couldnt hear it at all. I use to run a 750 Holley#4779 on my 5.9 crate engine on the street in this!Even in Indiana winters which are not that bad. It might get 10 degrees with 16 inches of snow total. My concern was loading or fouling plugs every 2-3 months. I kept that thing in tune with a MSD dizzy. If you have never used one you will be amazed at how easy it is to adjust and plot your timing curves. They even have a version for S.B. only that has vacuum advance curves! It is the E-digital and has hundreds of possible curves, both mechanical and vacuum. 3 wire hook and its burnout time! You could easily bump up your timing and reach that detonation area then back down 1-2 degrees and it would be perfect. A budget way would be to put a timing adjuster,(msd), and it would give you 18-20 degrees adjustability at the dash! BTW Jon did they curve your dizzy and send it back to you? This summer,(07), I think I am going to purchase the digital msd e-curve dizzy and I will have a extra MSD billet dizzy if you want to go that route, Ill save it for you. I want to try and get maybe 2-4 more MPG with Vac. Adv. since I changed that beast of a cam to a smaller one. 292/.509 to 264/.495. 4.10 Detroit Locker with a truck,(granny gear), 4-speed.

I used to run a 284 MP cam years ago with a 2800 stall convertor too.

That is a pretty mild cam by todays standards but still stands as a first real step up the performance ladder without a rough idle or real increase in fuel consumption (although you use more fuel because you push the car harder to get that grin on your face. )