im restoring my 78 f150 and rebuilding the old 351m in it i have been playing with the idea of building it into a nitrous motor and just wanted to see if anyone else has and howe did it hold up?? my plans are reground 400 crank and rods with arp studs edelbrock aluminum heads and tmi 14cc pistons to make the compression around 11 to 1 a lunati bracket master2 cam edelbrock performer manifold and a plate style wet shot nitrous kit probally only around 50 to 100 shot what do you think? will it hold up?

 

How often do you plan on spraying it?

I have a 400, .060 over, cast aluminum pistons, 8.5-9.0 CR, 10/10 crank, stock rods and hardware...

I spray it 60-70 times a year with a 100 shot using an edelbrock wet kit with the plate that bolts between the carb and intake.

It shouldnt have held up this long, ive probobally sprayed it almost 200 times by now, but it does, and its also my DD truck..

I havent had a single problem from using N2O with my engine, although i would never recommend for anyone else to do with thiers what i have done with mine, especially since my truck weighs in at just under 5,800 pounds with all the junk i have on it.

The 400 seemed to like the nitrous alot, dropped 2 seconds off my 1/4 mile ET at an un-corrected altitude of 5800 feet, the corrected air is usually around 9,000 ft.

Using Edelbrock intake, and stock heads, no 'porting' work, just a 3 angle valve job. .484/.510 $100 cam in it...

The truck actually does better with the exhaust capped and running thru the mufflers than it does with open exhaust...

Alot of the engine guys i talk to around here say that the bottom ends really wont support much nitrous use...I know it puts alot of force on the crank, but with nitrous i usually shift 300RPM lower than running N/A, and finish the run still about 600RPM higher in the traps than my best N/A run.

I dont think i answered much, but it may give you an idea of what i am doing, and how i am doing it, so you can have a better idea of real life experiences vs theoretical

 

well i apreciate any input and yea i wont be spraying it that often just want to get the ole 400 a little kick in the pants probally spraying it about as much as you not too often just when im at the track or when i pull up next one of them little ricers hahaha i love humiliating these kids in their cute little honda civics in a 30 year old truck

 

oh forgot one thing what mufflers are you running??? im indecided between flowmaster 2 chambers or moroso spiral flows

 

I am running the Flowmaster 40 Series mufflers, these ones, right here...

Flowmaster 40 series mufflers

The truck was actually snappier, and had more torque WITH stock manifolds on it too, but upper RPM died about 500 RPM lower than with headers.

The nitrous got me 2 seconds flat, like i said, but before the nitrous i also switched from an edelbrock crab...err...carb.. to a holley 650 DP. I spent about 2 days tuning the carb, went back out to the track and just switching from the 650 edelbrock to the 650 DP Holley also shaved 2 seconds off...

The 40 series mufflers have a pretty nice idle resonance, and a very attractive WOT. I highly recommend the flowmaster 40 series, ran all the way out the back, or atleast dumped infront of the rear tires. I have my exhaust setup : Header flange...reducer....6" 2.25dia exhaust, then mufflers. The in cab sound is annoying, but outside of the truck sounds great. I know the in cab sound would be reasonable if the exhaust was ran to the back.

Next summer i will most likely be switching back to stock manifolds, with single 3" exhaust, and ofcourse, a flowmaster muffler.

BTW, the 100HP shot of nitrous shaved half a second off of the trucks 60' time. Which is amazing , a 100HP shot dropping the 60' time half a second in a 5,800 pound 4x4 f-250..lol

 

yea ive pretty much decided on the flowmasters ive had at least one set of em on every truck ive owned and you gotta love the sound

i was planning on running a colector reducer 12" and 2.5" diameter flows then turndowns

 

Pffffffffffffffffffffffffffffft, this is the only way to run the exhaust on 400:

 

o my good golly gosh... wow i bet that sounds amazing and im not being sarcastic..cuz i liked the sound my truck made after i put the headers on and no exhaust

 

yeah sounds not bad, i go deaf if i'm not wearing a helmet when i drive the truck though lol.

 

What are you running with it? Speed pit??