How deep was dish when you had heads off and looked? Not positive, but I think they still used the .020 gaskets in 70. You may only be at 9.2 :shock: High comp 4bbl 70 block I had used flat top cast pistons. No dish or valve reliefs. Your running well if that's the case! :TU:
Here's a vid of what a stock 350 can do (and how well it holds up) under nitro. Low comp engine, TH350 trans with stock 'verter, 3.73:1 gear, and one of those 'crappy' stock cams, as well as (probably) plenty of miles on it. http://www.youtube.com/watch?v=co7fE0BNWt4 Plenty more videos on Youtube with him running mid-12's. Gary
--Your 60 ft. times are still better than I could get at 1.90's no matter what I had my son try that day,.. that stiff suspension seems to hook pretty good.. Also, nice compression figures.. ---LOL, I can't remember what the pistons looked like, honestly,.. dish I think,... and the motor was a factory 70' 350 2bbl - 260 hp,.. would they be that much difference between a 2 bbl. & 4 bbl. pistons, just because of the carbs... --- I know the SP 350-315 hp was listed 10:0-1 comp. motor.... ---I wished I would have CC the heads ,.. I know they were milled at least .030 if not more, because looking at the hour dial and dots were cut into pretty deep... I've learned to look at heads this way when somebody tells me the heads were cut when there off the car for inspection,.. ---I've had my 455 heads cut .030, .040 and .060 thou. before, and you can tell a difference how much was cut off.. some of you might know what I'm talking about... its just what I do with buick heads for a quick check for milled heads.. thanks for listening,.. jerrold ---------- Post added at 08:35 PM ---------- Previous post was at 08:24 PM ---------- Gary,.. cool vid,.. who's car and how much juice are they feeding it... might have to get some slicks, that car left hard...lol
Not sure who it is, but he experimented with different bottles ranging from 125-200. I think He was on the 150 or 175 bottle on that run. The 150 and 175 bottles seemed to be best all around efficiency based on the runs. The 200 bottle didn't give much more than the 175 bottle. So I reckon for a bone stock Buick 350, adding a 150 bottle for 'emergency' use on the street would work out pretty good. Aside from the fact that it's just cool as hell, I posted that video to show people that the stock 350 is pretty durable and that beefing up a stock engine and leaving the bottom end stock works just fine. You also are demonstrating this yourself. :TU: Gary
Demonstrating my nitrous ignorance above, 'the bottle' I've learned typically comes in 10 lb. sizes, ranges from 50-250 (or 300) 'shot' calibrations (in 'wet' form), and can be adjusted to suit or set up in stages. Uses 0.8 lbs per 10 seconds for a 100 HP 'shot' and works best with a bottle warmer to keep velocity/pressure up. Seems the 'wet' mixture is the safest and most reliable way to go, albeit a bit more expensive. Most expensive part would be initially buying the 'kit' or 'system' from a reputable source with all the safety accoutrements (highly advised). After that, the refills wouldn't be too terribly bad. Did me some nitrous homework last night! lol Very interesting chemical. Also very tempting... Talk about a 'hang on to your nutz' button! :laugh: I imagine it would work great with a Quadrajet that typically doesn't use the full CFM potential of the secondaries (on a stock/mild 350), but would with a nice 100 shot added underneath it! I imagine it would bellow out pretty loud once the nitrous hit. Gary
Hey Gary The Nitrous "Shot" or amount (Wet System) is controlled by a jet for the Fuel and a jet for the Nitrous. Some systems have jets so you can get 25 hp increments. The bottle simply contains the nitrous. The Nitrous/Fuel ratio is based on the nitrous at a certain pressure and is typically around 900 psi. I believe we had to keep our bottles at 86*F to maintain a slightly higher pressure and purged down to 900 just before launch. It's been a while. As you use the nitrous, the bottle pressure drops and the system goes rich. The larger the bottle or nitrous volume the less pressure drop there is per second during use. Paul
Yeah I read up a bit about it last night. Pretty interesting. Now that I think about it, the Qjet comment I made would be more for the dry spray method. Seems it would be good up to a point with the wet system until the pressure got weaker and the shot richer like you said. With dry, it seems the carb (like in the case of the vacuum secondary Qjet) would be a bit more forgiving as it adjusts the fuel need to the added oxygen of the N2O. I would think a nice setup would be a switch for the valve to turn the bottle on, with another switch that didn't actually spray the nitrous until you were at full throttle, such as a switch set up like a detent solonoid for transmission kickdown on ST400 and ST300, to ensure it never sprays unless you're wide open. There's other considerations too, such as lower RPM WOT it should be less, then progress as the RPM increases so it's not in danger of pooling in the manifold. Having a pressure guage to read so you'd know when it was getting low, etc. I'm sure the systems have all that stuff, and if not, could be procured. Of course with all that extra energy comes heat, so a top notch cooling system, closer gap on plugs and/or higher voltage on coil for ignition with the heavier fuel/oxygen charge would be mandatory I'd think. Very true! One could make it more stable for longer periods of time if the pressure in the bottle was raised and the valve releasing it only released a certain amount (lower HP 'shot' mayhap), which is probably how the lower HP shots work I guess. So I reckon the harder you push the bottle, the less stable the results are (balls out at first, then goes downhill fast from there). A '250' shot bottle, or one capable of up to that, if pushed or regularly used at 250 (wide open setting) would be a bit quirkier I'd imagine than the same bottle regulated down to 100, for example. I dunno. Either way it seems it's like a hot young date that you don't intend on marrying. Hard and fast then burns out quick. lol Total novice here on this sort of thing, though the concept isn't new to me. Just never really had much interest in it to study it. (I'm talking about the N2O, of course :laugh: ) ...but then comes that video of the stock Buick 350 running mid 12's, and it made me go 'hmmm'. Main idea was to simply show how durable the engine is and it got me to thinking about Nitrous Oxyde. haha Gary
Gary,I'm no nitrous expert by no means,but I think the "dry" nitrous system is only for fuel injection systems that can read an O2 sensor to enrich the fuel for the added oxygen nitrous adds to the mix when burned. A carb can't enrich the system unless its setup to run with nitrous full time with some sort of a nitrous fogger system. But if set up like that,you wouldn't want to run it when the nitrous tank loses pressure.(trailer car only,unless you were to change the carb or jetting at the track) Derek
Derek, you are correct. Dry kits are made to use with a fuel system that can "read" o2 levels and adjust fuel delivery. Carb'd applications need an additional fuel source to safely add the n2o/fuel combo and avoid leaning out. Nitrous if used correctly is definitely fun (I havent had it on a car, but had a dry system on an injected motorcycle and boy was that a trip!:eek2 but if the proper tuning/fuel delivery isnt there, you are begging for big trouble.
Dry systems don't mix fuel with nos in manifold .just means manifold has no fuel in it.but O2 can't compensate enuff for nos by itself .different fuel pressure regulator and injectors with programming of ecm required.
I can tell you how much fun nitrous is it ripped the driveshaft right out of my car, tossed it aside and said I need stronger drive shaft and u-joints. You get about 4 -5 Good runs out of a 10 lb. bottle and a 125 shot. Running the bottle pressure at about 950 is the best spot. Heat the bottle up too much and the pressure goes up and you get a nice Boom when you hit the switch. I could keep up with a supercharged v8 95 Mustang on a roll and when I raced him from a roll out of first gear at 20 mph I got a car on him and he could not pass me. I hit the rev limiter almost instantly at 6200, I never lifted and just banged 2nd. I am surprised I did not blow the engine up on that run and I have made a bunch of runs at the track after this. When I used the turbo 350 with a 3500 stall the engine would go to 5 grand when stomped, I would shift at 5800 and it would only drop back to 5 grand. When I put in the 200r4 in I bought a 3000 stall to bring the rpm down and gained 1 mph in the 1/4 and got down to the 11.81 with this set up spinning the tires 10 feet out of the hole. I went from 13.50 to 11.81 in the same day and go from 99 to 114 mph in the 1/4. I had 420 rwhp and 460 tq on a Mustang dyno. It's like Dr. Jeckel and Mr. Hyde and launching the car out of the hole on the bottle is just ridiculous.:eek2:
Wasnt that TheGreatOne or TheOne ..Nick A.? pretty sure he was in the 11s on on gas with stock engine
SWEET!!! :gp: Derek ---------- Post added at 11:46 PM ---------- Previous post was at 10:36 PM ---------- As we know that nitrous is limited to about a 150 shot max when running a D/P intake. Just to add to the nitrous fun,when the S/P intake comes out you'll be able to do a 500 HP shot if you would want to go that much.:Brow: Derek
Why not use a direct port system if you need more nitrous? Think about it for a second. Port the heads with larger valves with a lot of attention to the exhaust ports. Forged pistons with a true 10:1 compression Good rods. Nitrous cam 224/236 on a 114 LSA. Use the aluminum D/P manifold with the port nitrous nozzles. Add a 300hp shot. Drive all day on the street with a tame 300 hp. Go to the track with 600 hp Paul
TTT,..Updates to car:.. Better Exhaust system, 2 1/2 pipes into 15" flowmaster bullets dumped at the rear axle..,putting battery in the trunk for weight transfer,..and changing to a shorter drag tire in back in hope's of moving the car faster off the line,..will also be unbolting the sway bar links for weight transfer...at the track... Looking for that 12:99 at 103 mph...:Brow:........ Test -n-Tune in 7 wks. Thanks for listening,..
Ttt,...Update;.. We did race high school nationals and broke out first round with a 13:24 at 100.7 mph, do to tinkering with the 750 holley DP,.. I had jetted the 750 a little lean and it would not pull hard in 3rd gear, the first pass showed that at 97 mph at 13:55,.. and 13:35 at 99 mph...jetting 73 frt. prim. and 79 rear.. Remember now,.. the 850 holley was 78 prim. and 80 rear and ran 13:24 at 102,.. so I figure jet it like the 850 holley dp and let it rip... we have nothing to lose except first round ..lol So first round with new jetting also we added 90/10 shocks I had laying around and loosened the frt. sway bar did help launch... and put on smaller/ shorter 27 x 10 x 15 hoosier quick time tires,...everything else on the car staying the same,.. dialed at 13:30... ==My son stalled the car hard at 2800 we launched and went 13:24 at 100.7,... 750 is still on the car and drives great around town just like the 850 holley did,.. I don"t know if I can pull the 102 mph out of the 750 holley,.. there was no other runs made with the 750 holley that day and we left the track, might be some tuning left on the table,..so I might put the 850 back on to back up the previous times at the track,.. The track air temps were close from the fall temps to spring temps if anybody was wondering,.. This little 350 sbb is alot of fun and surprises alot of people,.. my son took it to the dairy queen and one guy thought he was running a big blk by the sound of it, that 310 cam has a wicked sound,.. LOL,..
