33IMP
Well-Known Member
Wallace says 242-245 at the crank, depending on if you enter mph or et.
Horsepower Estimate?
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33IMP
Well-Known Member
ir3333
Well-Known Member
Tx 33imp....here's the build
lo compression 73 cast crank motor
1.88 intake valves
melling replacement cam .444/.429 and .204/.210 duration
600 cfm carb
3.23 gears what should this car run in the quarter?
lo compression 73 cast crank motor
1.88 intake valves
melling replacement cam .444/.429 and .204/.210 duration
600 cfm carb
3.23 gears what should this car run in the quarter?
I see it the other way around they unlock 80 hp.
The stock 340 x heads are good for about 400 hp gross with a reasonable build. So say a stock 340 does make 275 hp gross so there's 125 hp waiting to be unleashed what's mainly holding it back, Cam, Exhaust, Carb etc.. why wouldn't they add decent power?
Why do you think LS/gen 3 hemis make 150 hp gains with cam and headers, it's the potential not being used, even a 318 has like a 150 untapped hp out of stock heads.
Same with stock 1.88 j heads 375 hp should be no problem, what's holding it back Cam, Exhaust etc..
Now with compression ratio it's just gonna raise or lower the entire curve a few percent for each point you move from. If you think of 10:1 as the middle of 7-13:1, I say with the appropriate intake/exhaust a 10:1 240 cam 340 with stock 1.88 j heads should make around 375 hp.
Op's engine falls a bit short of that but by not much.
33IMP
Well-Known Member
360?
Sounds like a pretty stock rebuild, so I would expect pretty much stock numbers. But of course, you know that it's ENTIRELY dependant on the car it's in. It'll run better in a 3000lb a-body with a 4speed and slicks, than a 4800 lb B2000 van. It'll probably run pretty good in a 2000lb tube chassis race car with gearing and a good converter.
You talking the OP's engine ? If so he's running a bigger cam then that 235.
That 391hp 340 article isn't close to reality. Back in the days when that dyno was fairly well know for being extremely happy. The stock number is really close to right, that last test... nope.
It was the source of a lot of disappointment when people went to the track with the same build and never got that 390-400hp expectation on the slip. Hard lesson.
It was the source of a lot of disappointment when people went to the track with the same build and never got that 390-400hp expectation on the slip. Hard lesson.
If you smoke the tires and run 13.@110 the 110 tells you at that weight its a making this much hp to turn that given mph. At that mph and weight if the gearing and traction are spot on you can run as quick 12.44
I never said et time slip but you can use it in other calcs
mph and weight is as close as youll get to figure quickest et based on weight and hp of said engine if you change something and mph goes up the et that you could run drops accordingly
At some point when everything is matched gearing converter /clutch traction etc @ a given weight 3400 lbs the only way to go faster is more hp or pull weight out
dynos are all different
The strip tells the truth
I would have expected you to know this from your experience
If i was street racing all i cared about was there trap mph so i could know if they would be running me down
57 chevy i street raced twice was trapping 110 111 at the track i trapped 108 highest trap speed so i knew he be comming for me
I had seen launch he had traction issues
I sucked the paint off him 1st race best pass i ever made in that car beat him a good amount
He went home race gas advance the timming ice in the cool can 2nd race i hit the spray@40 mph in 1st went sideways not a great pass he missed 3rd to 4th shift he was at my side mirror he was gone
He did not ask to race a 3rd time
57 chevy 327 sold cam single plane 750 dp 175 shot 4spd m-22 4.56s shifting @7500 i was told
70 duster 340 g/k243@50 108 in 106 508 lift rhoads lifters 2.02s 185 psi torker 650 dp unilite 1 5/8 headers 125shot 727 stock stall L-60-14s 26.99 tall 3.23s trapped in 2nd gear
About as unmatched a combo as you could get it needed slicks 4.10s and a 3500 verter and a 750 dp i think it would have run 11.80s
I always asked the pussies with gears if they wanted to race a 1/2 mile or mile no takers
This kid worked in and engine shop marine/race/passenger car
He had everything available to him
He laughed at my car when i asked him to race
His eyes lit up when i said 3.23s auto no stall
Which setup had more potential Mr Newbomb Turk?
Even if so, most of these magazines builds are done by the same people dyno by the same people and are the numbers most are familiar with. Generally when people think 350 hp there thinking in line with these numbers not Joe Blows Dyno Room no matter how more correct his numbers maybe.
Does it matter if Magazine hp is 390 hp, Joe Blows is 360 hp, and 1/4 mile calculator is 290 hp ?
To me as long as we know they equal each other that's all the matters, and generally were not privy to Joes Blows numbers so they don't matter much to me since I don't have access to them.
PRH
Well-Known Member
Indeed.
It got fixed after one of the Enginmasters competitions.
Initially, the prelims were done at 3 locations.
It was something like the best 3 from each location would meet up at Westech for a shoot out.
The entries from the other two locations miraculously picked up a bunch of power on the Westech dyno.
Then there was some statement made regarding some anomalous weather system, and that was the reason for the discrepancy……….but then at some point after that the story became, the barometer being used at Westech was pretty far off.
I seem to recall it being said that with the new barometer readings, the power numbers were about 5% lower.
But……..I saw some old tests from there where 5% lower numbers would have still seemed too high.
We used to joke here that the Westech numbers were “retail HP”.
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I've monkeyed with the weather station in a dyno a few times to make the corrected numbers look a bunch better than they should be. Had a customer at the shop wanting X hp and it was close but not there.
An old vicks vaporizer does wonders to a correction factor. Real temp 70 and 15% humidity 29 in. What the dyno thought 115, 80-90% humidity... correction factor way up. LOLBefore I learned how to get into the software and change up the code!
I'm not disagreeing Westech has a happy dyno or not, IDK, but for most of us those are the numbers we generally have had access to and know, be it magazines, engine masters show, Richard Holdener etc.. To you guys in the know maybe those numbers are like generally 20 hp higher or whatever, to me the main thing is the hp added, don't care if on their dyno it went from 290 to 390 hp but in reality it was 250 to 350 hp.
PRH
Well-Known Member
This is a rhetorical question……..since I’m not going to argue about it.
Post 100……..which is the truth?
Newbomb Turk
Well-Known Member
I’m not sifting through all that.
My point stands.
You don’t have a clue how much power an engine makes by a time slip.
You only know what it did in that car on that day with that driver.
That’s ALL you know.
Maybe the engine is making 100 hp more than the time slip but the junk car is eating it up.
Your lack of experience with engine dyno’s and what they say is clouding your judgement.
Your time slip without a dyno sheet is as worthless as a dyno sheet without time slips.
So your time slip doesn’t tell you everything you need to know. Not even the half of it.
what did it make
pretty close to my engine minus the headers and miles
Then dont respond i never said time slip et
mph turned and weight is more correct then a dyno
clearlt et cant
mph and weight are dead nuts on the nose
Newbomb Turk
Well-Known Member
PRH
Well-Known Member
You had a good guess…….
378tq/343hp
The magazines create unrealistic expectation. An xe268 will likely be a high side of 1.1hp/ci stick in an oem style/stock headed 340-360 with a great tune up.
If I told you Billy Barty was 7 feet tall and had a tape out (dyno) that showed he was 7 feet tall, would that be ok? What if you met him and he was really 3ft 9in. Just because it's the data you see or read doesn't make it valid, nor supportable when other data shows the build is way off base. I've said it many times, built a couple 360's with a xe268, rpm/ld, 750dp, dougs/tti/5204's and good OEM heads (equivalent to the dyno derby pieces) and NONE of them made more than 360hp. NOT ONE.
I'm not going to engage in this with you, carry on if you like.
Selling parts is job one for them.
If I told you Billy Barty was 7 feet tall and had a tape out (dyno) that showed he was 7 feet tall, would that be ok? What if you met him and he was really 3ft 9in. Just because it's the data you see or read doesn't make it valid, nor supportable when other data shows the build is way off base. I've said it many times, built a couple 360's with a xe268, rpm/ld, 750dp, dougs/tti/5204's and good OEM heads (equivalent to the dyno derby pieces) and NONE of them made more than 360hp. NOT ONE.
I'm not going to engage in this with you, carry on if you like.
Selling parts is job one for them.
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PRH
Well-Known Member
Imagine how bad you look then
that is how nhra fctors hp for the classes 40 or so years
wake up
thats what said
you cant say why ask?
if the 60 foot time sucks 15.0
if its the best it can be 60 foot 14.0
no point
both could turn the same mph
is it in 3000 lb car or 3600
cant even guess
cmon
Newbomb Turk
Well-Known Member
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