Ok, I'll forgive you on the Red pump thing. I'm sure you meant well but I wouldn't recommend droppin the pressure switch down to 4. On the 75 shot it pretty hard to hurt things but I would make a habit of trouble-shooting things that way. With your fuel cell up front, that helps things alot. That is the best way to configure it. Mounting the safety switch to the open port will work fine and should keep it from surging. If you need 5 psi, set the switch for 4 3/4. Get that filter away from the solenoid! Put a larger filter just before or after the pump. You don't want any restrictions between the regulator and the plate. The fuel wont respond fast enough. Shimming the pressure spring and going to a bypass regulator was a good idea. It might just work. Start with a better filter in a different spot and moving the switch. That 75 shot won't keep you happy for long. THe first car to beat you by a fender will fix that. :rant: :TU:
I had up to 275 Hp jets but then had some back-firing as you might remember. This was before I bought that compucar plate from you that wouldn't allow things to fit under my hood It'll have plenty of room under the Olds hood though . The bigger jets are much more rewarding... Anyway, OK on the filter. I blew through it and it seemed a bit restrictive. I have already installed a 3/8 filter before the regulator. The diagram that came with the regulator recommended both filters, so that's what I went with, but I'll take your word over theirs and ditch the little one. It helps explain the problem. I'll also re-set the hobbs switch. Bob and Rick, thanks for the help, and I'll update you when I get the changes made.
I'm glad you are relocating that filter- if you have 5 PSI from the regulator, that will be lower after you go through a filter. The regulator should be the last thing before the solenoid (except the "T", which will be in parallel and won't cause a pressure drop). I think as long you have a filter on the outlet of the pump, that will be sufficient. Let us know what happens. By the way, I have recently acquired a 350-2 in a Sportwagon, I am considering putting a small nitrous shot (50-75 HP?) on that. The nitrous should be able to compensate for the small carb, especially at higher RPM. -Bob C.
V.E...... Don't count on not needing more carb with nitrous. Nitrous tends to increase the volumetric efficiency of a motor putting a high cfm demand on the carb. I've seen dynos and runs at the track where a smaller carb slowed down a nitrous car. Nitrous will definitely pick it up but don't expect more rpm. :Smarty:
Update on my setup. I moved the hobbs switch and trashed the ford filter from my solenoid. The system works great. I dusted off a friend's 740 hp blown dualie (don't ask me why, but he bugged me to race) and really gave him a show when I hit the juice at the top of second while in front of him. Hoosier quick-times won't hold even a 125 hp shot at ~60 mph. He now says "wait until I get my other pulley and nitrous hooked up." I think I'll be seeing what a 454 looks like spread all over the pavement when it happens. I've got the right fuel pressure and it's just clean hard-pulling power. I'm almost afraid to try the 175 hp jets. Looks like it's about time for some ET streets too. hee hee, what a rush! You don't have to inhale the stuff to make you giggle, that's for sure. Oh yeah, the oil turned black right after. I can think of 2-things; too much blow-by, and blowing all the carbon off of the pistons, or both. Thanks again Rick & Bob!
Forgot to mention, I'm running a 9x11 converter (YANK Converters) which stalls at about 3800. I think it may need tightened if I start to use the juice regularly.
Spark Plug tuning... I found this page that deals with reading plugs and it has pictures to go by. It saves me alot of typing. :TU: http://www.angelfire.com/fl4/pontiacdude428/Readplugs.html I would post it if I didn't think it was good S%@#!
Plugs are clean, however it has a bit of a sloppy idle with the hemi killer cam. I assume the overlap contributes to carbon buildup as well as being a little rich to help smooth out the idle... using that great link, I'd say my UR-6's are very close for daily use and I might be able to lean it out a bit (I haven't shut down correctly to do a proper plug reading.)
New Nitrous Cam Is In..... Here are the specs of my "Nitrous" cam. 256/278 .773"/.714" (w/1.7 rockers)112 LC. :shock: Power band 4800/5200-7000/7200-shift point. installed at a 107 ICL. Recommended stall @5000 on the nitrous. This cam will get the bolt-in TA lifter girdle instead of the bonded in plates. Plus the NEW Schubeck Roller-X lifters. Not what I would have picked for a cam but after talking to Jay Allan of Cam Innovation he changed my mind. He's not your everyday "Cam Guy", he's more of a cam design engineer. I initially told him if it wasn't bigger(more duration) than what I was currently running, I didn't even want him to touch my cam blank. He is extremely intelligent and runs a lot of numbers to get the cam figures he wanted me to run. After he expained to me the things I needed to know I had him grind my cam. Not that the "Big" Azz Nitrous cam wouldn't have worked but just not as good as this one should. I wont say YET that this is the way to go but I wouldn't have spent the money I did if i didn't believe it will. It cost a good bit more to have a cam designed for your motor over just picking some numbers and having them ground to a stick. If you think my cam has "stupid" fast ramp rates, I have seen #'s to a turbo Ford SB with 248degrees w/ .785" lift(.462" lift at the lobe) 1.7 rockers. :jd: Ford's do have a much bigger base circle to work off of. I actually have 2 cams that were ground for my motor. The other is a low lift cam: 262/278, .714/.678" 112LC. This was a small core that didn't have enough material on it to grind what I initially was suppose to get so Jay had to redesign a new cam profile. I ended up buying another "soft" blank to get the core I needed/wanted. I did have to pay extra to get it heat treated.-Twice!After it was ground to get it to the Rockwell hardness needed to keep it from failing or twisting. I was told my cam was one hard Moe-Fo.... TA doesn't sell the "soft" blanks any cheeper than a heat treated one. Go Figure..... o No: :af: But it is heat treated After it is ground which is better than a cam that is heat treated Before it is ground which makes mine much stronger. Also, my old cam obviously wasn't heat treated good enough/deep enough since the back lobe on my old cam started "flaking"-"Breaking up" on the top of the lobe. I had noticed the roller was "tracking" on the lift portion of the lobe on the last take down of the motor. I chose to run it anyways and now it is broke thru the top hard layer of the cam. At least I didn't sell it before it failed. If all goes as well, I will have my 55mm cam for the new block ground on the same concept except a little more insane since it will be based on a 55mm core. :Brow:
How did you arrive at the 107 intake centerline? I dialed my 308s in at 112 based on my dynomation software, (not that it is necessarily right). I thought maybe it would like being retarded more than the average 455 because of the 494 cubes and relatively small heads. o No: But that's just a guess...
Jay Allan had the information all on the cam card/build sheet. It also had a cam doctor run on prior to it being shipped giving me .006, .050, .200" duration numbers. The 107 ICL is the cam recommend installed ICL. Most "nitrous" and some "boost" cams use excessive exhaust duration to help evacuate the cylinder better. Nitrous specifically has a faster burn rate due to the increased oxygen content in the chamber. As a result of the faster combustion burn, you have to retard the ignition timing, but also complete the burn process sooner which allows you to open the exhaust valve sooner without a power penilty. So by taking a cam that is ideal on motor and using it as a baseline, you add most of the duration to the opening side of the exhaust. What this does is, with everything staying the same, is shift the exhaust centerline giving you a wider lobe seperation angle. Let say you add 10 degrees to the opening side of the exhaust on a 108 LC cam. This now makes the cam a 110.5 LC cam. So to keep the same ICL as before you would have to advance the cam 2.5 degrees. For example Take a 260/260 @.050 with 108 LC install straight up with a 108 ICL Add 10 degrees to the open side of the exhaust to make the Cam a 260/270. Now since 10 was added to the opening it only shift the exhaust centerline half the amount which would be 5 degrees so the exhaust now has a 113 centerline. Now take the 108 ICL with the 113 ECL, this gives you a cam with a 110.5 LC advance 2.5 degrees. Get it? This is just a baseline "rule of thumb". To get the added power in the range your looking to use it in, some add duration to the cam ,some add lift, some widen the LC, some you a combination of all or some. It depends on the motor combination, its limits, and air limitation. I don't think retarding your cam beyond 108 is a good way to go. If you want to keep the same duration then widen the LC to get more rpm out of it. Retarding the cam just causes it to loose power across the board.
D-Con... Its nutty but the 210S Ive got in mine now runs way better on n2o than my 308s ever did..only did it cuz I killed the 308s at Reynolds when I ate the motor burpin it with the gas after the burnout..didnt have the timing taken out and it was set on kill (125s in bigshot with super bigshot noid)...call me crazy ..go ahead :beer fish
Aw geez, another question I should have asked earlier. Now I have to decide whether to pull the front cover off again or not! :rant: JW told me he pretty much sticks to a 108 ICL, I shoulda listened... Nitrousfish: I wonder if the 308s was too much for your heads?
Kick IT" No, it's was from try to stuff 15lbs. of crap in a 5lb. bag. ou: I believe the 125jet is for 400HP shot of nitrous. Yes the 308 is very wrong for a 400hp shot w/iron heads. To get away with a 400Hp shot of nitrous with iron heads, in my opinion, you would need 9.0-8.5 comp, 230/255 or 235/265 cam, 114 LC advanced 6-8degrees. Everything staying together, this would put a 350hp motor in the 700+ Hp range on nitrous. At minimum, you would need a TA single plane and headers plus a fuel system to keep up. The best way would be to put a 1 gal fuel cell up front for the nitrous and run a Holley Blue pump and regulator. Don't plan on much rpm past 5200-5500. An 11" nitrous converter or even a very tight 10" would be plenty. A window switch would also be a must as a big shot at low rpm would tear the ring lands off the pistons. I wouldn't engage the system below 2000-2500. A two stage would be best. :blast: :eek2: .
Rick- I've thought about doing something like this, but I'm worried about finding one that will mount safely, and also passing IHRA/NHRA tech inspection. Have you done this successfully (or seen someone else do it)? I would love some more info, perhaps in a PM since it is kinda off topic for this forum... Thanks, -Bob C.
Bob, Jegs and Summit sell one just for this purpose; JAZ brand. I have one in my car (on Rick's advice). I think it's the only way to go as it almost totally eliminates the question of fuel supply to the N2O system. I mounted mine where the battery tray used to be. So far the inspectors haven't given me any flack, but the tracks I go to aren't exactly sticklers...
1 Gal Fuel Cell Part #'s Summit: SUM-290-122 JEGS: JAZ NITROUS ENRICHMENT CELL#547-220-001-01, Mount#547-400-001-03 There is no problem with mounting this up front. The only rule is that it has to be outside or seperate of the drivers compartment. :TU:
I do believe if the cell is in front of the core support there must be tubing around the cell to protect it from frontal impacts.
Rick... Yeah I was not thinking when I did that...musta been too much icehouse the night before and not enuf brain cells left over ..fish ou: :error:
