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Gypsy Jo 11-21-2009 07:34 AM

napa engines
Questions: are all 454 the same horse power?
Napa engines as good as anybody?
Thanks in advance I know 350's come ina lot os different hp.but when I asked napa what horse power 454 was they said it didn't list hp just said standard 454 will this work in 77 Argosy?

silverleeper 11-21-2009 08:31 AM

what is horsepower? WikiAnswers - Whats the difference between horse power and torque

Just like 350s, 454s can be built for different applications. A standard 454 will probably do fine and puts out about 220hp but a built one can put out around 500hp. Lets say you add some thing like an RV cam. You can increase the torque and thats better for hills. Just a few changes can make a world of difference.

Do some research and find out what you want out of the engine and then talk to good local gear-head and find out how to build that engine.

Mikethefixit 11-21-2009 08:58 AM

Check out Jasper Engines also.

overlander63 11-21-2009 09:56 AM

There are three basic versions of 454: Car, light truck, and RV/medium duty truck.
The car engine usually has higher compression, lower torque and more horsepower. Light truck has lower compression and more balance between horsepower and torque. RV/MDT generally has more torque and less horsepower.
Torque is how much an engine will pull, horsepower is how fast it will pull it.

Gypsy Jo 11-21-2009 10:12 AM

Lee, thanks for the info put that site on my favorites list.Cleared up hp and torque differences.Good thing to know.
Roger ,checked out jasper engines very helpful about 2500 more than a napa I'm sure its worth it.
Terry ,I want both!I really hate going uphill slow and if I'm not careful I find myself doing 75 or so in my sob mh.
So I called back napa cause their engine is so cheep.Wanted to know about an rv cam in engine he said no I would have to buy one and install it but when I talked to jasper engines they said since it was for a moho theirs would have an rv cam in it . Do you think the guy at napa knows what he is talking about ?Also checked with Jasper on atranny not a bad price. Many things to think about.

2airishuman 11-21-2009 02:30 PM

who will do the INSTALL?

IF planning to PAY some1 ELSE do the engine install...

ask them about where to get the crated or rebuilt 454.

a 28 gosy isn't THAT heavy so there aren't a lot of internal mods needed on the 454.

and it CAN be enhanced with headers, exhaust, better intake and so on...

also the tranny issue needs to be addressed ideally before assembly.

also the issue of MPG matters and these things can be THIRSTY if not done correctly.

generally napa is a reliable source for parts and with good warranty service.

BUT an entire engine is a big deal and the warranty might be worthless, once the 454 is tweaked for rv use.

these are just remanufactured engines right? whereas many of the enhanced crated engines are NEW=more $$

find your craftsman mechanic.

IF they've done many transplants it's likely they will have an opinion on the best source for the 454...

and IF it's a diy job, best of luck!

this one was tweaked out, such that i received an award from a montana state trooper...

for going 80 something UP hill in the mountains...:D

the honor of 'fastest damn moho he's seen' cost me 5$.


Stefrobrts 11-21-2009 04:32 PM

In the gearhead circles I travel in (mustangs, mostly) Jasper has a pretty good reputation, where Napa is regarded more as the place to buy your engine when the grocery getter has blown it's motor and you need to drop something in just to get back on the road long enough to sell it. I think the response that the Napa engine comes only one way (because they are remanufactured and mass assembled by cheap labor somewhere), compared to the Jasper engine which probably has a lot more options available because they will assemble it the way you want it before it heads out the door tells you what you need to know.

When I needed a 302 for my Mustang I bought a kit from PAW and got exactly what I wanted right down to oversized valves and whatnot, picked out my cam, and assembled it myself. It was actually easy and fun. And when we got it in and heard it fire up, man was I proud. That motor is still running strong. Building an engine isn't rocket science, just takes attention to detail and an accurate torque wrench.

Another thing to consider is that a remanufactured engine might already be bored out as far as it can safely be done, and the next big rebuild might require a new block - so if you plan on keeping it a long time, and think that next rebuild might come on your watch, you might want to go with a motor that hasn't been bored out too far. A good shop should give you those specs when you buy the motor.

And of course the biggest consideration is how much your wallet can handle. Sometimes you have to go with the one your wallet likes best, and deal with the rest down the road.

Picking up a book like this might help you get a feel for what all goes into the rebulilding process, and help you ask the right questions when you pick one out How to Rebuild Your Big Block Chevy (0075478001750): Tom Wilson: Books

Gypsy Jo 11-21-2009 05:57 PM

I get what I pay for .So I'm thinking the jasper engine and tranny might be the way to go. It will certainly deplete the restoration fund but I can always get more money I only want to do this once .If I start out with a goodstock 454 with an rv cam I could go back with all the original equipment ,intake manifold,exhaust and replace later on.i have more research to do have been searching the threads and have found favorable mentions of jasper Also they will deliver to my door!!Great option when youare staying in the boonies.
2air 80 uphill woohoo.I would probably get a ticket too.Did you do the work ?This will be a diy but I can call in backup when needed with mechanical experience.
Stephanie I had thought about rebuilding it .I have had a lot of ideas .With my situation now it looks like a crate engine is my best option.Wallet is probably going to scream but what is money for except to spend.

garry 11-21-2009 07:39 PM

For me;

1st choice would be from Jasper built for MH application highest $$$

2nd would be a crate 454 from GM Chevy dealer (36,000 warranty) for MH application.

3rd If you know the history of your current 454 rebuild from a local shop.

Last NAPA crate.

safari57 11-21-2009 09:04 PM

Doing an engine swap is a ton of work. I have swapped engines I've built engines I've bought, many times over the years. There are a lot of extra costs like fluids, hoses (don't use the old ones, it just isn't worth it to not change them),block heater, hose clamps, etc.

Try to get an engine that has been broken in on a dyno first so you don't have to go through the cam break-in at start up (this is where a lot of new engines get killed from the get go) and you know it is a tested engine that should light right up when you are ready to go.

One thing I learned about rebuilders is that they frequently re-use parts that "look" good or are still within acceptable tolerances. The problem is that these can also be on the backside of the average scale so still okay but no where what you'd get with a new engine, which means you have already limited the life of the engine this time. Keep in mind a rebuilt engine was rebuilt because it has already been worn out and typically the re-builder will not know what life it lead before they got it. You should be asking what parts in this engine are not brand new? Most rebuilders reuse rods, cranks, and other parts that are (hopefully) properly tested and resized, but others have been known to also reuse the oil pump, timing chain, push rods, rocker arms, etc. Many rebuilders reuse the old valves, regrinding them and doing the seats and may not replace the guides, then put in new valve seals. So is the life of these parts 90% of what a new one would be or 50% or????

Surprising to many people is the number of people who build hot rods who now buy GM/Ford/Chrysler crate engines. They just got tired of doing it themselves, running back and forth to the machine shop, making sure the parts guy gave them the "good" parts and not something made on the cheap in some distant land. They got frustrated at having rebuilt engines that they bought crater much sooner than they should have. It is not uncommon to install an engine and find out it has low oil pressure and then find out the re-builder used the old oil pump "because it looked good and was within acceptable tolerances". And most of us have realized that we really haven't saved all that much by the time we were done.

So if you can afford this it makes sense to buy a new crate engine and you get a decent warranty that is honored anywhere they have a dealer and the life span should equal the one that comes in a brand new vehicle. Or, if you are going the rebuilt route, make sure you buy from the best re-builder you can find, with the best record, good warranty, and find out who they use nationally (since you are traveling) to deal with warranty issues. Check Better Business Bureau, on line forums, and you are also getting lots of feedback from folks on the Airforums. Also, make sure you understand what the impact of you doing the installation versus a licenced mechanic has on the warranty. And in all cases find out if the engine has been dyno'd (and thus broken in) which is a huge bonus. It may add some cost to the engine but well worth it.

It is a lot of work pulling the old engine out and replacing it and this is all done at your cost and your effort so doing the swap once with the best quality parts you can afford is well worth the extra bucks. Yes, one can live on Kraft dinners for a few months and not bloat significantly:D. And remember, if the replacement wears out quickly or breaks you are the one doing all the work again, eating the costs of fluids, etc. all over again.

We don't have Jasper here so I cannot comment on their product. I do know several folks who have bought kits from PAW and done their rebuilds in the past and been very happy with the results. The prices are good and the parts quality seems good. Make sure you can access a quality machine shop if you go this route.

It is not hard to rebuild an engine. Just make sure you have a very good assembly manual. You mention you can call in knowledgeable assistance when needed which is good. There is a lot of pride in doing a rebuild, but it still feels pretty goshed darned good to also install a quality replacement engine you bought. It is still a lot of effort and cost on your part and with that completed you can feel pretty good about having done that. One is LOT of work, the other is still a lot of work. Most people wouldn't even attempt to do that much.

Good luck and let us know how you make out.

2airishuman 11-21-2009 09:31 PM

and barry...

as difficult as it is to do a swap in an OPEN hoodless auto...

double that effort and time for an classic a/s moho.

it's like working on an old vdub, only sae.


how about a nice diesel ?


safari57 11-21-2009 10:51 PM


Originally Posted by 2airishuman (Post 774145)
and barry...

as difficult as it is to do a swap in an OPEN hoodless auto...

double that effort and time for an classic a/s moho.

it's like working on an old vdub, only sae.

You are right 2air, a van or a MoHo swap is much more difficult than compared to a car. Once would be quite enough for me at least. Actually, nowadays, I don't think I'd do it myself. It is surprising what some small shops are willing to do the work for if you aren't in a huge hurry. You bring them the vehicle and the replacement engine (and transmission if you are doing both) and they have all the tools, the knowledge, to get it done quickly and correctly. And while they are doing that you can use the time to earn more money to pay for it all........:innocent:


nti06 11-22-2009 12:16 AM

When I read:

"So I called back napa cause their engine is so cheep."

I almost closed the window.
For what you are doing, you do not want cheap. You want quality, however at a reasonable cost. At the Ford dealer I worked at, we did service motorhomes. They are hell to work on. The labor rate at that dealer for motorhomes was $100 per flat rate hour. Coach builders build coaches with no regard to serviceability of the chassis. Techs at the dealer I worked at have had screws into gas tanks, chassis harness spliced into and cut into. High amperage battery cables routed next to fuel lines. Its ridiculous.

So if you want to fix it, it will cost money, but spending the right amount of money to fix it right the first time, will keep you from spending twice that amount to fix it all over again.

Locate a local engine builder, who can build you an engine for power and durability.

GlenCoombe 11-22-2009 06:23 AM

The last post makes more sense that most anything said so far. Work with a local builder if you can. That way if you have any trouble the guy who built it is at hand.

Your new motor is the heart of the beast and should be the highest torque, to get you rolling easiest, and highest horsepower you can afford.

It is hard to get everything in one motor but with a little effort you can get the best compromise for your needs.

If you use a local builder you should look at the old block to see if it is serviceable and rebuild it. You may want new heads, flow and port them. And research fuel injection as the prices for complete systems have come down. The smallest I've found is 750 CFM which is about 100 cfm too much.

Dyno the engine prior to installation! Great advise above too. If you can find a performance shop builder they will understand what your looking for and it will likely be a bit of a departure from their normal routine of high HP but will be within their knowledge area.

While the motor is out it's time to figure out all the accessories that you can keep using or replace. Having just done this I replaced the rad and added an aux. electric fan up front of the rad to supplement the clutch fan. Heat is the enemy. Take a look at my photos and you'll see the 4" cold air intake build up of the air filter housing. Get good clean cold air into the motor in bunches.

Of course new motor mounts and belts... if I had it to do over I'd have changed the mounting for the alternator. New billet mounts aren't cheap but they sure work well.

Of course I could go on but it's your money not mine. Bottom line...go local!! Build gobs of low end torque. Remind your builder the engine will never rev beyond 3K rpms.

Don't forget MSD Ignition and headers into 2.5" max exhaust system.

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