41hp 426 - Dyno Sheet Included

[bkelley]

I was going through some old emails between a friend and I and found this. This was his dyno run for his 426 which includes an 88mm 11:1 JE piston, stage 2 cam, 42mm 450r carb, ESR Airbox Eliminator kit, full Sparks exhaust and a mild port and polish job. Figured I'd show you guys. 41hp is quite impressive.

http://img413.imageshack.us/img413/8476/dyno1.jpg

[tri5ron]

That is impressive, but seems a bit high. All things are possible I guess. very nice.

[smelly$cat]

Looks legit. I dyno'd 38hp with my 426 with a stock cam and stock carb, but, 12.5:1 compression. All other variables look about the same.

[PaRedneckRiders]

wow thats pretty impressive
Id like to put my 426 on the dyno when shes all said and done to c what kinda numbers i can pull

[416racer]

Do you know what gearing was used during this dyno run?

[bkelley]

Not sure on the gearing. And Ron, I promise you it's legit. He's a duner and runs with the piped and jetted 450s all day. This dyno sheet is what makes me want a 426 kit so bad. I still haven't decided what I'm going to do. I'll be in real trouble once I actually get the money together.

Edit:

Another sheet

http://img401.imageshack.us/img401/9709/dyno2.jpg

[ridgeracer]

MMMM....it's a beautiful thing

[JOHNDOE83]

Thats a really nice dyno run, Looks like he went fairly big on his jetting...id bet thats where alot of that power came from.

I wish there were some 440 dyno sheets around?

[bherriman]

These things aren't diesels..more fuel doesn't mean more power..at least last time I checked. I regular gasoline engine will make more power if you actually lean it out a little bit but it will also run hotter and you run the risk of burning a hole in the piston. If you go dumping fuel into a diesels it will make more power...and heat.

[JOHNDOE83]

Actually, anytime you add more air flow, you have to add more fuel to get the power, pipes, cams, filters, and bigger carbs need you to have more fuel flow...and anything with a bore needs alot more fuel.

So ya, you do need to add more fuel to make more power sometimes...in air cooled engines thats a mojor factor.

If what you said were the case, then we should have more power with stock jetting, and all this jetting for mods that has been done is useless?

[bkelley]

Generally speaking, more air plus more fuel equals more power.

[Barrymaxx]

For a gasoline engine 12.5-13 AFR is usually what I go by for optimum power for cars.

This seems a bit leaner. I wonder if it would make more power being a tad richer.

[bherriman]

Yea no kidding adding a pipe or filter cam and what not would flow more air and yes you would need bigger jets for it to run correctly. I understand more air equals more fuel and more power. You stated that he ran pretty big jets and THAT is where his power came from..which is incorrect. His power came from increasing the displacement and adding things like pipe and cam and then jetting correctly for these modifications. your statement suggests that I can just go throw in bigger jets and make more power.

[JOHNDOE83]

Originally posted by bherriman
Yea no kidding adding a pipe or filter cam and what not would flow more air and yes you would need bigger jets for it to run correctly. I understand more air equals more fuel and more power. You stated that he ran pretty big jets and THAT is where his power came from..which is incorrect. His power came from increasing the displacement and adding things like pipe and cam and then jetting correctly for these modifications. your statement suggests that I can just go throw in bigger jets and make more power.

No, actually I said "I bet thats where alot of that power came from", I never said thats "where" it came from.

I never once said anything about just throwing in bigger jets to add power.

I made a lil comment about his jet size and you went off about diesels??? which has nothing to do with the subject of the thread, and now your attacking my credibility?...which is fine, I dont mind, but please try to refrain from thread jacking!

[bherriman]

Originally posted by JOHNDOE83
Thats a really nice dyno run, Looks like he went fairly big on his jetting...id bet thats where alot of that power came from.

I wish there were some 440 dyno sheets around?

so " looks like he went fairly big on his jetting...id bet thats where a lot of that power came from" is not saying that the big jets he is running is producing his power? To me thats what it says. With out a doubt that is a nice dyno run. And yes a diesels do fit into what my post was about. You inferred that the big jets made the power which is incorrect in a gasoline engine. Running it a tad lean would actually make more power, its just hard on things. The only way to make more power with fuel alone is in a diesel. MY point here is not to try and prove you wrong. You post is just misleading to people that do not understand jetting completely, you are leading them to believe that the big jets made the power not all his motor work.

[tri5ron]

I think this has strayed into a case of perspective, context and symantics.

The only way to have a accurate debate, or to maintain a common line of conversation, is to stay on the same perspective, within the same context, and not be confused, or derailed with symantics.

Jmho.

Alot of youngsters come here to try to learn.
We,... as the more experienced,... need to remember that.

Accuracy is key.

Again,...
Jmho.

[JOHNDOE83]

WOW....in the atv dyno section....theres a 426 hiting 47 HP!!!!

http://www.exriders.com/vbb/showthread.php?s=&threadid=291086&highlight=426%2A

Its from turbo530r so id think it also was legit, it also has a 200main jet!!

[honda400ex2003]

Originally posted by bherriman
These things aren't diesels..more fuel doesn't mean more power..at least last time I checked. I regular gasoline engine will make more power if you actually lean it out a little bit but it will also run hotter and you run the risk of burning a hole in the piston. If you go dumping fuel into a diesels it will make more power...and heat.

I went down a jet size with my 450 carb from my 400 carb. so this does happen! steve

[honda400ex2003]

Originally posted by tri5ron
I think this has strayed into a case of perspective, context and symantics.

The only way to have a accurate debate, or to maintain a common line of conversation, is to stay on the same perspective, within the same context, and not be confused, or derailed with symantics.

Jmho.

Alot of youngsters come here to try to learn.
We,... as the more experienced,... need to remember that.

Accuracy is key.

Again,...
Jmho.

unfortunately true, it seems this one, like most others on this forum has seemed to go down hill quick again today. i posted the previous just to state the fact that it does happen. it really is getting sad that most of these once informative threads turn out to be, he said she said when none of it can actually be put with numbers. I have numbers for mine, as do you ron so i guess we can back up what we say. most cant.... steve

[MtnEX]

Sorry... but I have ridden very hot 440EX builds that didn't churn out that kind of power.

They MIGHT have made high 30's fresh after break in... 40hp would be extremely generous.


I say do a 416 when needed, then a 426 next time and so on...

Just because someone can show you a nice dyno sheet doesn't mean you are going to jump into the 40's with a 426... and you have just bypassed that 416 bore size you could have ran, worn out, and bored again to 426. So once the 426 burns down it's time for a sleeve.....

[dr qwerty]

I thought those numbers looked a bit low,
I ran a 39whp with 426 11.5.1 dyno tuned, open air box, lrd full exhaust....i would assume with a cam and 450r carb i would hit 45whp and run with modded 450's which is what they hit on the dyno

I know this thred is pointless with out my sheet, i will look for it today or tomorrow.

[JOHNDOE83]

What size jets were you running? just curious?

[jcs003]

the Hp numbers are nice but the torque is barely above stock. the curve also deviates from the more usable stock curve. im not completely impressed. but as a duner i assume the power is where it is needed.

[sc400ex_rider]

Originally posted by jcs003
the Hp numbers are nice but the torque is barely above stock. the curve also deviates from the more usable stock curve. im not completely impressed. but as a duner i assume the power is where it is needed.

Thats because stock the ex is a torque monster.