G30 van and Edelbrock. Opinions?

Hi. Posted here quite a while ago. Time for more ideas. I like reading some of the great, informative posts here. It's been educational.

Ok..to help explain my cryptic subject line, I own a 79 class C motorhome built on a Chevrolet G30 van chassis. It has a 400 CID engine that runs very well. It has good enough power to propel the 5 ton vehicle on level ground quite nicely. It can easily keep up with all traffic..until I have to go uphill and, let me tell you, here in Alberta we have some nice hills. ;-)

It really runs out of breath to the point that I have my foot to the floor trying to keep it barely traveling at 70-80 kilometers per hour [about 35-50 miles per hour]. It could never make a trip to British Columbia, which is ironic since it was built in British Columbia. It burns no oil and compression is 140 at the lowest and 150 at the highest. I have rebuilt the carb and did all the standard tune-up stuff. [filters, plugs, wires, cap, rotor, coil...] I am happy with how well it runs, it just needs more grunt. I have verified that the secondaries are indeed opening.

It has been suggested by a few engine builders I have met that I might have great luck with an Edelbrock Performer Plus camshaft and a Performer or Performer Air-Gap manifold. I have decided against headers as the excessive heat may be too much under the doghouse. It's already rather warm for my front seat passenger. Not to mention my XYL's objections to the throaty sound that we all love. *sigh*

In the past I have considered engine swaps with a 454 or a Cadillac

500. Both would probably be great but I really don't need the extra work or expense.

The graphs at Jegs show a rather surprising jump in torque from 2500 to 3500 rpm which is right about where you need it most on the highway with a motorhome.

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I've noticed that Edelbrock treats the small block 400 a bit different compared to all the other small block Chevys with regards to the Performer Plus camshaft.
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Looks to me like it would all be good and quite inexpensive. Everything is in stock at a local speed shop just a few blocks away.

I am interested in a few opinions and perhaps a little discussion. I would not be opposed to more intense engine massaging during the off-season, depending on opinions regarding any potential benefits that any mods would provide.

I am really interested in your opinions.

Reply to
Opus-
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I don't listen so much to "graphs at JEGS" as to common sense. A low compression engine operating at low RPMs is not going to see miracle horsepower increases by switching the manifold.Switching the cam to an RV type may improve low RPM performance at the expense of top end passing power. But "Performer Plus" level parts are IMO not what you need if you are extending the duration of valves open.

Reply to
brianorion

ok i have a G10 van with 350 , had similar prob , great on flat ground , no power up hills , my prob was the lock up torque converter NOT kicking out uner exceleration , i dis connecter the converter wire and fixed my problem , you may want to see if you have a lock up torque or not ... also my boss had a 83 chevy van style motorhome , he wanted more power , and we put in a 400 cid ..with edlebrocks 400 performer cam ...and it sucked going up hills . we ended up changing the cam to a seal power / TRW RV cam , lower duration for more bottom end torque .. he siad if he went up the hills in 2nd gear it was fine but motor screaming around 3000 -3500 , and thats were you siad it made your power on the graphed ...not were you want it , you need peak power around-2000- 2500 in heavy vehicial also check your Mechanical advance , use timing light , remove vac hose from disributor , reve engine , timeing should advance , maybe total around

15-20 ... . if it dont move then wieghts maybe siezed , get that fixed , remove cap, rotor spray wd40 around wieghts and work back and forth with hande ( put rotor on and move with hand ) they should snap back on there own ... and if you do have a cat converter , maybe good ideal to cut it out and just put in pipe , 30-50 $ fix at exhaust shop ... hope this help

Reply to
Chevy

On Sun, 23 Jul 2006 16:08:40 GMT, "Chevy" spake thusly:

Were other parts changes, or just the cam? Was the distributor re-curved? In my case, I do not have a lock-up converter.

Well, my motorhome has 4.56 gears and it turns at 3000-3500 on the highway. Might be ok.

The previous owner installed a 2.75 single exhaust system with a Flowmaster muffler [part number unknown]. I will be installing both the cam and intake and I will re-curve the distributor for quickest advance, as per Edelbrock instructions. The vacuum advance will run on manifold vacuum, not ported vacuum.

I have also posted my inquiry on several other forums plus read up on other motorhome owners experiences with similar modifications. The majority of responses have peen positive, with regards to improved power where I'll need it. We'll see if I will see any gains.

Reply to
Opus-

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