A
Anonymous
Guest
What would be the most shot with nitrous on a basiclly stock 300 engne and feel safe as to not having any problems?
Chemical limits are the stock 150 hp net hp *1.47, gives 221 hp. Thats a 71 hp shot maximum.
Beware! FrenchtownFlyer has more experience with 1000 passes of 300 six quarters, plus a few years yeomen duty in a dyno cell. He says the stock cast pistons will most likely cray enough before then.
My advice, go a 50 shot as a undercarb kit using one conservative fogger N20 jet and a rich fuel jet.
Beware! FrenchtownFlyer has more experience with 1000 passes of 300 six quarters, plus a few years yeomen duty in a dyno cell. He says the stock cast pistons will most likely cray enough before then.
My advice, go a 50 shot as a undercarb kit using one conservative fogger N20 jet and a rich fuel jet.
A
Anonymous
Guest
Would a Hypereutectic piston help any on withstanding this extra surge?
They should do. You'll get the fit of a cast piston and some extra strength; none of the cold rattle that can occur with forgies. The most recent Turbo Falcons run hypereutectic pistons and they have been boosted by owners way in excess of factory ratings - surely a similar stress situation to a modest shot of nitrous.
Adam.
Adam.
A
Anonymous
Guest
so does anyone think that a stock (minus intake and exhaust) EFI motor could withstand a 50 shot?
I'm unqualified to say if the 300 has a piston issue under nitrous oxide. I do know most 351 Windsors I've striped have had cracked pistons but still driven just fine. It is likely that the stock 300 has a lessor factor of safety than a 302 does because its primarily a low rpm engine. A 302 has varied from wild 4V GT, to lo-po plodder, then to wild 4-bbl the 5.0 EFI street screamer. As a result, 302 and 5.0's have had a lot of develoment work done on them with some very solid pistons over the years.
The 4.9 six is a low compression plodder which was never designed to go over 5000 grand with those pistons.
When I look at this happening on Wildjohns stocker, I'd make sure I'd never go over 50 hp shot, and dial the ignition back by whatever means.
I've seen records of Jay Storers 1932 Coupe with a rebuilt 300 with turbo runing 9 pounds, and propane, blow a gasket, and then live to do a 12.9 second qaurter in a 2800 pound car.
And 1000 FrenchtownFlyer passes with a rebuilt 300 in a wild state of tune.
If it were me, I'd beg steal or borrow a stock rebuild but with added forged pistons, and dial up 70 hp and 125 lb-ft of torque from an emissions legal truck.
The 4.9 six is a low compression plodder which was never designed to go over 5000 grand with those pistons.
When I look at this happening on Wildjohns stocker, I'd make sure I'd never go over 50 hp shot, and dial the ignition back by whatever means.
I've seen records of Jay Storers 1932 Coupe with a rebuilt 300 with turbo runing 9 pounds, and propane, blow a gasket, and then live to do a 12.9 second qaurter in a 2800 pound car.
And 1000 FrenchtownFlyer passes with a rebuilt 300 in a wild state of tune.
If it were me, I'd beg steal or borrow a stock rebuild but with added forged pistons, and dial up 70 hp and 125 lb-ft of torque from an emissions legal truck.
A
Anonymous
Guest
I'm inclined to go with xtaxi, with my knowledge of the 3.8. A stock non SC CAN handle a 50 shot and they rev to 5500 (limited 5250 and bad things happen around 6000).
Since all N2O does is help it breath I'd say spend the money on a head, but hey thats just my perfrence. I want power from 0-just shy of redline, and that is why I perfer Roots/Screw over all else (well that is after N/A).
Since all N2O does is help it breath I'd say spend the money on a head, but hey thats just my perfrence. I want power from 0-just shy of redline, and that is why I perfer Roots/Screw over all else (well that is after N/A).
I do not like giggle gas; I've seen too many good engines ruined by it. So take the following analysis in that light:
A stock 5.0 Mustang makes 215 HP @ 4200 RPM (269 ft-lbs of torque) and 288 ft-lbs of torque (181 HP) @ 3300. Add a "safe" 50 HP shot to that and those numbers become:
265 HP/331 ft-lbs @ 4200
231 HP/368 ft-lbs @ 3300.
The torque numbers are what is important here. The torque increases by 28% at the torque peak and 23% at the HP peak. Since torque is a direct function of BMEP (brake mean effective pressure) that means that the average cylinder pressures increase by the same percentage.
Add the same 50 hp shot to a 300 and you get very different numbers. A stock 300 produces 150 HP @ 3400 (231 ft-lbs) and 260 ft-lbs @ 2000 (99 HP.) Bump those numbers by 50 HP and you get:
200 HP/309 ft-lbs @ 3400 or a 33% increase in BMEP
149 HP/391 ft-lbs @ 2000 or a 50% increase in BMEP
Basically, a 50 HP shot is almost twice as abusive on a 300 as it would be on a 302. I'm not at all certain that it still falls into the "safe" territory. It largely depends on how you use it but the capacity for major damage is definitely there
The point here is that low-revving engines can handle a lot less giggle gas than high-revving ones. That is how the 9000 RPM ricers get away with the amount of the stuff that they do (and also why when they do blow up, there's nothing but shrapnel left) If you're going to add nitrous to a 300, you may want to reduce the shot size or put in an RPM activated switch to keep it from kicking in at low revs, which sort of defeats the whole purpose.
A stock 5.0 Mustang makes 215 HP @ 4200 RPM (269 ft-lbs of torque) and 288 ft-lbs of torque (181 HP) @ 3300. Add a "safe" 50 HP shot to that and those numbers become:
265 HP/331 ft-lbs @ 4200
231 HP/368 ft-lbs @ 3300.
The torque numbers are what is important here. The torque increases by 28% at the torque peak and 23% at the HP peak. Since torque is a direct function of BMEP (brake mean effective pressure) that means that the average cylinder pressures increase by the same percentage.
Add the same 50 hp shot to a 300 and you get very different numbers. A stock 300 produces 150 HP @ 3400 (231 ft-lbs) and 260 ft-lbs @ 2000 (99 HP.) Bump those numbers by 50 HP and you get:
200 HP/309 ft-lbs @ 3400 or a 33% increase in BMEP
149 HP/391 ft-lbs @ 2000 or a 50% increase in BMEP
Basically, a 50 HP shot is almost twice as abusive on a 300 as it would be on a 302. I'm not at all certain that it still falls into the "safe" territory. It largely depends on how you use it but the capacity for major damage is definitely there
The point here is that low-revving engines can handle a lot less giggle gas than high-revving ones. That is how the 9000 RPM ricers get away with the amount of the stuff that they do (and also why when they do blow up, there's nothing but shrapnel left) If you're going to add nitrous to a 300, you may want to reduce the shot size or put in an RPM activated switch to keep it from kicking in at low revs, which sort of defeats the whole purpose.
A
Anonymous
Guest
..
I've got a problem with Venom. Their stuff may work great, but they insist on marketing it like complete snake oil. I realize that their primary focus (no pun there!) is the riceboy crowd who won't buy any bolt on that doesn't claim at least a 50 HP gain :roll: but I'd still like to see a bit of reality creep into their literature.
One thing I noticed about this kit is that it uses the stock injectors. That factor alone is going to limit how much HP you get out of a 300, which really doesn't have much room to grow in that department. If you swap to bigger injectors, you may need a re-flash or a piggyback chip, making this a less than "complete" kit.
One thing I noticed about this kit is that it uses the stock injectors. That factor alone is going to limit how much HP you get out of a 300, which really doesn't have much room to grow in that department. If you swap to bigger injectors, you may need a re-flash or a piggyback chip, making this a less than "complete" kit.
