All runs were made with open headers. Last December this motor made 801.4 at the same dyno and the air conditions were identical. I decided to freshen the motor up because I was having a problem with oil in the combustion chamber and a leakdown revealed numbers in the 6-12% range. It appeared as though the rings never did seal properly and they gradually went away over time. This was probably due to an incorrect cylinder wall finish.
While I had the motor apart I decided to upgrade to the Speed Pro Hellfire rings. Because of the large doses of nitrous I am planning to run, these rings should fit the bill perfectly. I set the end gaps at .032 top and .028 second which should allow me to easily run in the 400hp nitrous range. I also added a vacuum pump. On the dyno, the vacuum pump resulted in a 15hp gain and that is with only 10" of vacuum.
I would like to give a special thanks to Jim Moore(427Hotrod) for allowing me to bounce ideas off of him and giving me access to his experience. It proved to be quite valuable in a number of areas.
Re: 838.1hp on racing gas, 834.2 on pump gas - new numbers! (542C2)
That is beautiful!!!!
Ok, so I missed my guess by either 1.9 - 7 hp or 5.8 - 10.8 depending on gas used. I think you gave up too early....there had to be a few more in there!! :yesnod:
That sucker looks like it never stops pulling. I can only hope my next incarnation of mine will work somewhere close to that well.
Great job, and we're all looking forward to some strip runs. Is there still time this year?
Re: 838.1hp on racing gas, 834.2 on pump gas - new numbers! (542C2)
with a vacuum pump on the engine the oil mist in the engine is greatly reduced and you should make special provisions for oiling things like the wrist pins. drilled rods is the best way to do this. :chevy
Location: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
Re: 838.1hp on racing gas, 834.2 on pump gas - new numbers! (542C2)
Quote:
Light84vette: 542 cubic inches.
427Hotrod: No racing until next year. It's that rollcage thing.
69 N.O.X. RATT: I've divulged everything except the exact compression ratio and the cam. You've got to have a few secrets...
Cant blame me for tri'n. You should have a very good shot at a single digit time slip (without the NOS), especially with that new tranny. With the NOS it will be interesting just how fast it will be, hang on and bring some clean undies. There are some guys going very fast on 10 in. tires. What kind of heads and intake are you using, did you do the porting? Titanium any where in the valve trane? What is you open spring pressure? Any other tid bits you want to add, feel free :chevy
One last question, are you going to use a progressive controller for the NOS, 400 all at once could be tough on traction.
Very nice engine, and car for that matter, I am looking forward to seeing some time slips.
Re: 838.1hp on racing gas, 834.2 on pump gas - new numbers! (542C2)
So you probably have Drag Radial on your singray. But how much does your car weigh and is it an originall Corvette with stock chassis and body or is it a kit car Corvette because thats pretty old I think it would cost a lot of $$$$ to get one. If you have 400hp N20 then these numbers are w/o it right? 438hp ona 542ci seems kinda small so are you plainin on 1200hp!? WOW that would be some thurst machine. :yesnod: :yesnod: :yesnod:
Re: 838.1hp on racing gas, 834.2 on pump gas - new numbers! (542C2)
Truely impressive results Steve. Awesome. I can't imagine how much work and tuning must have gone into a 542 that makes over 800 on pump gas.
Jim is a great guy! He's helped me with just about every aspect of my 540 build. Hopefully, I'll get it finished soon so I can share the results with him!
Re: 838.1hp on racing gas, 834.2 on pump gas - new numbers! (69 N.O.X. RATT)
Thanks for all the feedback. Keep in mind that this car is actually my daily driver. Of course I have other cars to drive when this one is laid up but this is the one I prefer to drive. After having driven this car for a number of months with the 801hp motor, all I can say is that every drive is an absolute blast.
69 N.O.X RATT: I am still using all the parts I originally outlined when I first started posting to this forum. This includes the Dart Pro 1 CNC'd heads and a Dart manifold. I haven't done much to the heads but I did do the intake. The only titanium is in the retainers. Open spring pressure is around 750 lbs. And yes, I will be using a progressive controller with the nitrous.
Light84vette: I will be using Hoosier Quick Time Pros, 28.0x11.50-15. The car weighs around 3200 lbs, give or take. The numbers are indeed without the nitrous. I plan on buying the nitrous system this week. My past posts outline some of the things I have done to the chassis, they are quite extensive.
Flareside: There is a tremendous amount of work that goes into an engine like this. In fact, with a motor like this the work never seems to end. But this is what I enjoy doing.
Location: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
Re: 838.1hp on racing gas, 834.2 on pump gas - new numbers! (542C2)
I looked into the progressive controller also. The two things I learned about them is the Jacobs unit is sometimes not really highly thought of and they are hard on the selinoids (sp) due to the pulsing of them. I have heard that NOS reccomends rebuilding them after 12 runs.
Re: 838.1hp on racing gas, 834.2 on pump gas - new numbers! (542C2)
Holy smokes 1200hp!!!. I mean I plan on putting in a 482CID big block in my vette and with the addition of a blower I hope for 800hp(Trannies weak ;) ) but your making all of that and its only NA. When you mash the gas does the front end shoot up pretty high, think of it its only a scant 5lbs to a HP. How much $$$ did it cost to get this engine to pull those number on pump gas? :)
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838.1hp on racing gas, 834.2 on pump gas - new numbers!
