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DRR Sportsman |
Same coil on both, never tried a diff. coil. (Really hoping the HVC2 coil is hurt like Pat mentioned) Block has a #4 ground Frame to Pass. head, also ran a #10 jumper head to head. Never tried to switch polarity of pickup... My expectation was 1100 hp., real life Asphalt Dyno with my weight / et figures to 1084 h.p.. Dyno sheet from previous owner/PAR engines, on gas, 36.5 timing, 1163 hp @ 7000 / 927 t @ 6000, 14.40 AFR., (Dyno's lie!!) Cam: Erson, .510 (.867) / .475 (831), @.050 288/310, 116* inst. 115.2* > I installed @ 114*, never checked compression #, guess 15:1 I changed it to Alky & 5 stg. dry sump. Previous 601 w/ 365 oval, 1150 GAS APD switched over to Alky TERMINATOR - could keep the same dial in on the window.This message has been edited. Last edited by: Richie, | |||
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DRR Pro |
If its a Duggins cam its not gona like alky period. Scott doesnt care for alky on these bigger motors and will tell you that himself. The other sr20 deal I mentioned earlier is a PAR motor and he said from the get go it probably wasnt going to run on alcohol and he was right. | |||
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| DRR Sportsman |
I called PAR after my purchase to ask about switching to Alky and they said most likely I would lose H.P., but I was fine w/ that, I was looking for consistency and to help control heat. They did not say anything about it not working period..... | |||
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DRR Sportsman |
Richie, I have a couple old Dominators a 1050 and a 1150 you can try. Just let me know, they aren't being used and are just sitting on the shelf.  Man was not built to fly ... That's why he built HEMI's Frank Zeffiro ALIAS -- BIG KAHUNA | |||
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| DRR Sportsman |
Thanks Frank!, Thanks for the offer - I'll keep that in mind.  | |||
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| DRR S/Pro |
The call is yours to make. My question to you, is: For such a simple switch to a gas carb, and put gas into it, why is it that you won't proceed with this test to alleviate that out of the equation? Is it that, it is very possible that you won't have an issue anymore, but won't do it because you're determined to get it fixed on alky? You ask "how can I make a statement like that? We'll after 33 years of building engines, both alky and gas, owning a fully equipped engine shop, i've seen my share of odd occurrences, and I say what I say because it comes from experience. When your dynamic compression ratios become so extreme, you will put the ignition system under undo stress. The additional fuel in that chamber will cause this. The incorrect exhaust lobe will prohibit the burnt and unburnt fuel and air to escape. It's been proven time and time again, that in certain alky situations where as the dynamic pressures become excessive, that it causes a miss up on rpm and under load. strangemagicperformance.com oldsperformanceproducts.com WD dealer for just about all your performance needs. | |||
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DRR Top Comp |
I to agree with putting a gas carb on it to try. Since it takes so much less fuel for a gas carb that can quickly narrow it down to fuel supply / carb issue or electrical. Yes the car may be slower on gas but if it does not miss then you look at fuel system, carb or even cam selection. Once you put that question to bed you can move on from there. That is so easy to do and will answer so many questions and give you direction to go. I can guarantee you I would not be changing converters or any of that bull until I have eliminated the cheap, simple things. If you are determined to make alky work that is cool but still try a gas carb on there to narrow down where the problem is so you are not chasing your tail and wasting time and money. https://postimg.cc/gallery/np3zpruo/ "Dunning-Kruger Effect" -a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge. Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue. 4X NE2 CHAMPION. 2020 TDRA NE2 Champion | |||
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| DRR Sportsman |
Strange, ya got me on the experience end of things, with that being said....If alky was the issue why would it run Awesome for 1 pass and then 15 minutes later run like it wants to self-destruct??? that makes no sense to me, if it ran chitty all the time > YES! & I'm NOT using a alky carb...INJECTION.... huge difference. I changed torque converters trying to get it closer to the peak T. #'s which is 6000, first converter was 6800, others were 6500 > not to fix the miss.This message has been edited. Last edited by: Richie, | |||
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| DRR Top Comp |
Sometimes alcohol is hard to light off and some cam profiles just do not work well with alcohol. My first thought was ignition box but then you said you had already changed it out so I started thinking of next most likely reason. https://postimg.cc/gallery/np3zpruo/ "Dunning-Kruger Effect" -a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge. Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue. 4X NE2 CHAMPION. 2020 TDRA NE2 Champion | |||
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DRR Trophy |
Richie have you tried closing up your spark plug gap ? | |||
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| DRR Sportsman |
Bill, I have not, was at .035, will drop to .030 in Spring time. STRANGE...can you answer my question? | |||
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| DRR S/Pro |
Are you making a suggestion that only electrical can create an intermittent issue? On certain occasions there is no exact science as to why sometimes and not other times, and it's no different then what we classify as "intermittent".....and we also say to ourselves, why the number 7 rod and not the others, or why the number 2 rod and not the rest, and the examples go on and on and on. Mechanical injection is the crudest form of fluid delivery known. It is prehistoric in technology when you come to think about it and understand it. A system that continuously delivers the same amount of fuel regardless of the engines varying different torque outputs through the rpm range? Think about that for a minute. When you have mechanical injection, all your doing is tuning into an average over 1320 feet or an average over 660 feet. There might be 175 to 200 feet of that race track that it's actually optimized. P.S. I know exactly what would happen if you stick on a gas dominator and run it on gas, and a set of new plugs. It will run without issue. It will have zero issues at that point. P.S.S.
Might not be a bad idea to actually figure out what you have, especially when on alky. How can you plot a camshaft out if you don't know the compression ratio? Piston speed, cubic inch, static compression, type of fuel all have a serious impact on how the camshaft should be ground.This message has been edited. Last edited by: Strange Magic, strangemagicperformance.com oldsperformanceproducts.com WD dealer for just about all your performance needs. | |||
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| DRR Sportsman |
I RESPECT your opinion Strange, But I disagree...What your claiming is: When your dynamic compression ratios become so extreme, you will put the ignition system under undo stress. The additional fuel in that chamber will cause this. The incorrect exhaust lobe will prohibit the burnt and unburnt fuel and air to escape. <<< this is all mechanical, my cam isn't changing going down the track > it's going to let the same amount of air/fuel in. A system that continuously delivers the SAME AMOUNT of fuel regardless of the engines varying different torque outputs through the rpm range? Putting the 632 back on GAS would be my last ditch effort, I would put my 601 back in (ran 8.00 @ 169) to determine if the miss is car related or not, first lets see how my coil & MSD check out w/ Pat. As far as cam selection, this was a starting point for this motor...I'm VERY OPEN to changing the cam to make it happier if indeed that was the problem. STRANGE: what would YOU select for a cam? Putting this 632 back on gas & on the dyno, might not tell me a thing, except costing $400, atleast buying new parts I have something to show for my money. Compression ratio, I would have to assume PAR engineered it close to 15:1, while re-building I kept everything as close as possible to the original build.This message has been edited. Last edited by: Richie, | |||
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| DRR Sportsman |
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| DRR S/Pro |
I am not here to argue or debate this topic. Do remember it is you that is having an issue, and it is you that has been having the issue for quite some time. I won't continue, as I and many here, years before have spoken their peace from actual experience and correction of this miss issue in an alky application. P.S. Don't assume anything. Take the cylinder head off, cc it, and get a number off the piston, or ask what the positive cc is of that piston. I can't, and I won't recommend any camshaft if the end user doesn't know exactly what compression ratio the engine is. The engine could be anything from 14.4 to 16.5 P.S.S. All the 632's, 637's and 638's that I have done, have nothing less then a 118 lsa, and have nothing less then a 116 intake install. strangemagicperformance.com oldsperformanceproducts.com WD dealer for just about all your performance needs. | |||
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DRR Trophy |
G,day, Only my 2 cents worth here, I'd have the plug gap around 22 - 24 thou on alcohol. You're not running too much timing? Have seen too much timing cause an audible miss around both peak torque and further up the rev range, engine was on an engine dyno, would pull past these points but clearly misfiring. First one or too pulls of the day, no miss - perfect. Get some heat soak and real temp in the engine, miss is back again. Plugs showing some pepper, pull a few degrees, - no miss what so ever. Hope you get it sorted, be interesting! Cheers | |||
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DRR Sportsman |
Assume nothing in the world of engine building. There was a fella here a few years back that assumed he had a lot of compression in his 600" BBC..... like 15.5 or something like that. Never verified with cc but as he found out later it was down about 3 points or so. Low compression and big duration camshafts dont work very well, lazy air speed, fuel puddling, to start with. Moroso makes a plastic slab that bolts to the block and after Vaseline over the ring gap you can calculate cc with a 1" bore reference, then cc the head, and know exactly where you are. Period. And as far as opinions,everybody will have one , but you need real info to find what the issue is. And my opinion is camshaft / compression related. And personally experiencing the fuel puddling, low velocity syndrome with a set of heads that had too much runner volume, fuel would just fall out at the fallback of the shift and it would not go anywhere but spit. | |||
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| DRR Sportsman |
O.K., I contacted my Engine man, we went thru the numbers and came up w/ 15.3 / 15.4, he has a gauge that I can 'ping' the motor while assembled to get the compression # and I will borrow that & test my motor to confirm. I sent MSD & Coil out today, Hope to hear from Pat by the end of the week. Thanks all... Paul, I run 32* | |||
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| DRR Top Comp |
I am sorry but can not understand why you would change converters, consider changing cams etc but not try a gas carb? If you have a fuel supply issue or electrical problem a new cam is not going to fix it. Lets assume you have a clogged fuel filter and it does not have enough flow to feed the alcohol you need. Since Gas uses about half as much fuel it may work well. If it does then you have just eliminated much of the ignition or electrical possibilities and narrowed it down to fuel or fuel supply. If it does same thing then you know to keep looking for electrical. Had a hose get messed up during assembly, it had a flap that came down blocking the flow. Looked perfect on the outside and did not leak but did not flow much fuel. Could be something like that. I will never go back to gas but would certainly put a gas carb on so fast it would make your head spin to narrow down an issue. Then resolve the issue and put alcohol back in it. Also I always run .028 on the plug gap to help fire off the mixture. I am a firm believer in dyno testing but I think in this case you are better to test in the car as I think the issue may be with the car. Maybe a clogged fuel filter, bad or kinked hose, bad ignition box. If it is one of those things a dyno may verify that it now works but would not tell you what the issue is. One other thing, when I had a miss on one pass I jumped out of the car and dampened a rag then wiped it on the headers to find dead cylinder. Good cylinder will boil water off in just a second. Dead or weak cylinder will not. Changing carb in the car is easier than changing motor and probably tell you more. https://postimg.cc/gallery/np3zpruo/ "Dunning-Kruger Effect" -a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge. Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue. 4X NE2 CHAMPION. 2020 TDRA NE2 Champion | |||
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| DRR Trophy |
G,day, I know nothing about your type of engines. I know with what I race, I run 24 - 26 with a flat top and 30 - 31 with a dome. Cheers | |||
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