engine has been rebuilt, only 281RWHP, what is wrong?

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I have a good idea what dyno numbers look like...

Hell my friend stock bottem end, comp cammed, AFR 165'd, Edelbrock RPM II car made 247/258 to the tires. That is low, does that mean its the norm, obviousely not. Your going to see cars making higher and lower power with the same mods, it depends on a lot of variables.
 
Gotta be looking at the whole combo.. those numbers with AFR's or Ported E7s.. it is apples to oranges... dont ya think?? just look at the sig and what else they are running.. cool?? I know on the TMOSS site, they show 260 WHP with my heads.. and a stock ported intake and a SD cam .. blah blah.. there are a lot of guys running 280-295 WHP on my ported E7s and small valves, not too many but a few kicking 300 WHP!! But they are also using a better cam/ intake/ tune / injecters ect... Yes they Probably could make more on a set of 1200.00 heads, but that isnt what they were after!! I think that 280 is no problem on ported heads... 300 whp is also there IF the other paramiters are met!! Bolting on a set of AFR's /Canfields/ ect arent the magic.. just PART of it!! cool?? also I wouldnt bolt on alum heads till you are knocking on the door of 11's with the E7s ( n/a) , then upgrade !! To me.. if you have all the bells and whistles, then you should have the 11 or better ET's for all that cost... but then that is
Just me..................................................

Thumper
 
That's a lot of cam .542 of lift, the heads would need a VERY good port job I mean stock they hardly even work past .500 of lift.

Some bottom end stuff will give HP... Domed pistons for example to raise CR is easy power, a decked block will give more power than a "non even" deck block (you want even cylinder pressures). Windage tray is good for some HP, clean up the lifter valley, enlarge oil drainback hole at the filter will also net a little more power...
 
GTOReturns said:
25th no punn intended. But I hear it all the time. My stock bottom end.... If its stock or its bullet proof does it matter? I mean the bottom end doesnt make any HP, it just supports it!

It actually does matter, as a well built bottem end with all the fancy parts will definately give you power. If it didnt why do all the NMRA racers run lightweight parts, offset ground cranks, different pistons, etc... Saying stock bottem end just means there is that much more to be had in the combo with a well set up bottem end.

Also typical numbers, and numbers that some people see will vary. I see a lot of typical cars and those guys are usually street guys that see the track once or twice a year. Then I see cars that go above and beyond typical and those are usually guys that more or less race their cars, and hit the street every so often. These guys would care more about squeezing everything out of their cars and they get the number they need!

I think automatically telling someone a car didnt put down a number because you dont "think" it can is stupid. Keep an open mind about it, listen to people with similar comboes, and remember just because the only people out there doing it are racers, doesnt mean the car your talking about hasent been prepped by someone with the same skill or desire to get the number.
 
85_SS_302_Coupe said:
LOL like i said, vs. 1) either the stock carb setup or stock EFI setup, 2) the way Ford rated their engines back then, and 3) when you combine a Wieand Stealth intake with a good running 4 barrel, yeah i'm sure you could pick up 53hp at the flywheel when you take into account those details. The numbers they show are at higher RPMs as well. I don't really think 53hp at the flywheel for those two items are a big deal at all :shrug: I'm sure they also bumped the timing and adjusted the curve and tuned the carb too.

I agree.....I've seen a few engines in real life at my school (i dynoed the one myself) gain way over 35+ hp on the engine dyno be gained just from putting in timing and tuning the carb a couple jet numbers smaller......and also like he says above, where in the rpm did it make that power? its like saying my engine made 300hp at 5,900 rpm and his made 300hp at 5,200, obviously they still made the same number but the second has way more potential in it and isnt maxing out like the first one.......btw I made 280.6rwhp with my combo on the SuperFlow dyno we have at my school....and I dynoed my friends bone stock speed density mustang with electric fan, and somewhat straight mid pipe, i dont even think it was bolted to the mufflers, sounded like ****, he made 206rwhp through his 5spd.....although I only revved it to 4,700 rpm cuz well it was taking sooo long to get up in the Rpms, and sounded like it was gonna blow up lol.....then we took off the intake tube to his stock air box and stuck it up in the air so the fan we had in front of the car would help blow some air in and made 216rwhp
 
GTOReturns said:
25th no punn intended. But I hear it all the time. My stock bottom end.... If its stock or its bullet proof does it matter? I mean the bottom end doesnt make any HP, it just supports it!


A light weight bottom end could aid in HP production. Also, when you say stock bottom end i assume that it has stock pistons and cam, so to me that tells me that all the cam specs are stock and that the compression will be at least close to stock aside from whatever increase that the aftermarket heads might provide.
 
85_SS_302_Coupe said:
A light weight bottom end could aid in HP production. Also, when you say stock bottom end i assume that it has stock pistons and cam, so to me that tells me that all the cam specs are stock and that the compression will be at least close to stock aside from whatever increase that the aftermarket heads might provide.
I dont consider the cam bottom end.
 
wasn't there an old trick for 302's where you just install the pistons + rods the wrong way (opposite direction) and it normally gains up to 40hp... since the piston gets a little more stroke and the piston goes a little over the deck (or even) for higher compression...

I'm sure getting rid of timing chain stretch is good for a few ponies... I keep hearing that synthetic oil gains up to 7hp at the flywheel according to dyno guys... :shrug: But lots of people make mistakes when building engines, they put on high volume oil pumps which basically robs the engine of power when you only really need that if you're running an oil cooler or looser gaps on the crank... huge oil pans also don't help, too much oil can also rob power...

Plus peak HP is only good for showing off on the internet in real life it won't help as much on the street. I'd rather have a 250hp @ 4500rpm then 350 @ 5800rpm... Just like honda's peak 200hp at 25,000,000rpm lol
 
How does a large oil pan hurt power? I'm trying to picture this but it's not coming to me....i understood that more oil capacity equals more oil to circulate through the engine and cool down, which would help power production if anything else. the only issue i could think of is windage, but even still it's not like the crank is any further into the oil just because you've got 2 extra quarts in the pan?
 
too much oil... from what I've read puting 5 quarts instead of 7 yielded more power at the dyno but this is the type of guy who would write 2 pages on how to save 1.5hp lol
 
Boss 351 said:
too much oil... from what I've read puting 5 quarts instead of 7 yielded more power at the dyno but this is the type of guy who would write 2 pages on how to save 1.5hp lol


I believe the idea behind less oil is just to prevent windage isn't it? Less oil circulating is going to equal higher engine temps, that's for sure. Hot engines typically produce lower peak numbers...i dunno, most racecars run higher volumn oil pans for a reason.
 
I'll re-read that section tonight, you got me all confused now. I ordered a larger oil pan anyway lol But a windage tray would prevent any oil from being propelled by the crank...
 
the 340 and 360 Cry were the first to do this, if the pin is off center it will leave the piston at dwell longer and increase piston speed...and all that is HP !! tricks the engine into thinkling there is a long rod!! the 360 guys used to brag 20-25 HP!!

Just me..............................

Thumper
 
thumper460 said:
the 340 and 360 Cry were the first to do this, if the pin is off center it will leave the piston at dwell longer and increase piston speed...and all that is HP !! tricks the engine into thinkling there is a long rod!! the 360 guys used to brag 20-25 HP!!

Just me..............................

Thumper
I'd take a 360 anyday over a 340. 340's were slugs! Even the AAR Cudas!