Hi, I recently bought a stock motor home 454/ th400 combo for my 1970 c-10. I would like to get about 500 hp. Can someone help guide me in the right direction?
I think he can get pretty closeHotrodrobert said:Three choices:
1. Lots of NO2
2. Lots of boost
3. Spend enough on those heads to buy a 500HP engine.
For sure you will want to confirm that you do in fact have peanut port heads. I harvested a 454 from a '79 motorhome and was surprised to find that it had the regular oval ports.techinspector1 said:Remove one valve cover and post the casting number you find there between the valve guides.
The assumption is brake HP unless RWHP is specified, at least to me. YMMV.butlerana said:no one asked rear wheel hp or fly wheel hp makes a big difference!
cobalt327 said:The assumption is brake HP unless RWHP is specified, at least to me. YMMV.
Given the same H.P. weather.Flywheel,Gross or rear wheel B.M.E.P. decreases with increasing displacement.And B.M.E.P.plays a great role in the durability of any engine weather S.I. or C.I.painted jester said:With me its always rear wheel horse power that pops into my head (probably because I ran rear wheel Dino's And did high speed tune ups on r.w.dino's)! Its hard to lean over a hood at 80 miles an hr on a drag car LOL
Its funny, people buy Big cu inch monster crate engines thinking their 500 horse power is guaranteed because of the adds and litrature says they were dino tested ! Then they bring em in and find out they have 275 hp at the rear wheels!! A lot really get upset and yell at me After doing quite a few crate motors that were installed in vehicles they average a little over 1/3 less hp at the rear wheels compared to their advertized brake hp!
But then you get the young guy that built a strong mouse motor himself did it right and its pullen 275 hp at 6500 rpm and climben the look on his face makes my day.
people dont understand you can put that same 275 hp mouse into another car and only get a reading of 210 hp at the same rpm or change to a lighter rear end dope and gain 3 hp! The big one I see most are the people putting in high volume higher pressure oil pumps and their oil pressures reading 90# at idle hot! they just dont understand how much hp and torque it takes to power that pump. Just changing fans can give your eng 5, 10, or more usable hp
I didnt have to write all that! I already know cobalt knows this and a lot more! but some visitors may not
topwrench said:Given the same H.P. weather.Flywheel,Gross or rear wheel B.M.E.P. decreases with increasing displacement.And B.M.E.P.plays a great role in the durability of any engine weather S.I. or C.I.
I know this statement is arguable with how you get to the same H.P. but it is generally true!
Decreasing internal component friction by the use of lighter oils always gives a small increase in H.P.
Removing ancilliary loads also gives increases in H.P.
Dyno adjustments,ambient temp,exhaust header internal condition(rust or carbon build up)can also affect the readings
I know Im splitting hairs here.Ive never seen two different dynos give the same readings.
Im not bashing dyno tuning,I think its a great thing!
Ive personally seen a S.B. load up to 800 G.H.P. at 9200,n that was at 209 C.I.D.with a little less than 2 ATM of boost!
topwrench said:You are right Jester,I think Dyno tuning is a great tool for getting the most H.P. out of an engine.
Sure beats running up n down the road to adjust stuff.
The number at the rear wheels is like you say always lower than the FWheel number.
Wow I dont no how many Flywheel H.P. would be needed to put 600 to the ground probably well over a 1000.
Some of you guys r lucky to live in a place where there is dynos available,
I moved here from Miami n its culture shock for Hotrodding
Nice work 12.3 is a very respectable time :thumbup:ethn_bert said:I used the article cobalt posted for my Nova
However I ended up running 8 to1 compression In order to run 87 octane. I get 21 m pg with an overdrive transmission. Naturally aspirated I run 13 flat in the quarter mile. With a 75 horsepower shot I run consistent 12.3 in a quarter mile.
Im very happy with the results. It was a blast on the Hot Rod Power Tour. It didn't cost me a fortune in fuel and I was able to cruise 70mph. I also enjoy participating in the real street class(7.50 and slower index w/ street tires) at the local track during the street racing events. I run a consistent 7.58 in the 1/8 mile if I get it to hookpainted jester said:Nice work 12.3 is a very respectable time :thumbup:
I also, have based my engine build on that series of articles (it helped me choose a cam)ethn_bert said:I used the article cobalt posted for my Nova
However I ended up running 8 to1 compression In order to run 87 octane. I get 21 m pg with an overdrive transmission. Naturally aspirated I run 13 flat in the quarter mile. With a 75 horsepower shot I run consistent 12.3 in a quarter mile.
Yes, If you read my thread it states that I used the peanut port heads with a Comp Cams xs256s camshaft. I ported and polished the heads with bulk of my concentration on the exhaust side. I used stock valve size, upgraded springs, and the matching comp cams stamped steel roller tipped rockers with 1 piece push rods.matts37chev said:I also, have based my engine build on that series of articles (it helped me choose a cam)
but I was a little farther into the head and cam upgrades that they did in later articles, with the same motor.
so do you have the peanut-ports?
and did you use the XE268H cam?
the reason I ask, is I am curious about the lower CR
sorry, but what thread?ethn_bert said:Yes, If you read my thread it states that I used the peanut port heads with a Comp Cams xs256s camshaft. I ported and polished the heads with bulk of my concentration on the exhaust side. I used stock valve size, upgraded springs, and the matching comp cams stamped steel roller tipped rockers with 1 piece push rods.
are the XS the same as the XE but soild lifter?ethn_bert said:Yes, If you read my thread it states that I used the peanut port heads with a Comp Cams xs256s camshaft. I ported and polished the heads with bulk of my concentration on the exhaust side. I used stock valve size, upgraded springs, and the matching comp cams stamped steel roller tipped rockers with 1 piece push rods.
very good, missed that i guess :thumbup:ethn_bert said: