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Need some more hp from a 350 in a 85 suburban towing a trail

General engine tech -- Drag Racing to Circle Track

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CamKing
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Post by CamKing »

randy331 wrote:Camking, will that cam really improve mileage,
As long as the driver's name isn't Andretti.

It's like Keith said, If you increase the low-end power so the driver won't have to put his foot down or have the tranny down shift every time he gets to a hill, the milage will go up.
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drifter
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Post by drifter »

Hey KEITH i emailed you a few times now about this combo using the melling cam and i have gotten no reply.I wanted to ask a few more questions since you have built a bunch of these towing combo's.My first question was with the added compression and cam lift do you have to do anything to the stock quadrajet carb? What about going 1 heat range lower on the plugs from stock is that needed? or not really How many miles do you guys like to see the customer put on an engine before he hooks up his 6000# trailer and starts hauling?
RW TECH
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Post by RW TECH »

Guys,

I helped a friend's dad years ago who had an 11K lb. welding truck that lacked power & drank gas like nobody's business.

We went for the gold by putting together a 400 small block and mileage IMPROVED over the 305 that was in it originally.

If this deal was mine, I'd put a torque cam in it like Keith or CamKing is recommending, and I'd definitely make it into a 383.

What oil do you run in it? If you do a rebuild, set everything on the mean to tight side and run light oil with a cooler. Switching from 5W30 to 5W20 is usually a 1% fuel economy improvement......

Also, you may want to consider replacing the exhaust catalysts if the engine's degraded in power & fuel mileage over time.
Keith Morganstein
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Post by Keith Morganstein »

drifter wrote:Hey KEITH i emailed you a few times now about this combo using the melling cam and i have gotten no reply.I wanted to ask a few more questions since you have built a bunch of these towing combo's.My first question was with the added compression and cam lift do you have to do anything to the stock quadrajet carb? What about going 1 heat range lower on the plugs from stock is that needed? or not really How many miles do you guys like to see the customer put on an engine before he hooks up his 6000# trailer and starts hauling?
Hi, I did not see the email. I'll check the junk or spam folder.




Start with the q-jet as is and go from there. You should have plenty of vacuum and a good idle. If it's a worn out tired Q-jet, you should rebuild or replace it. Secondary air valve adustment is important.

It will run well with an out of the box Holley 600 vac sec and minor tuning. I usually replaced the carb because it's just easier and ultimately cheaper to start with a new carb.

Use the regular AC 45 heat range or equiv. You can use the 44 heat range for extreme service, but I don't think they run as well.

Break-in? A few drives to sort things out, make sure there are no leaks, get the timing set, right make sure the cooling system is o.k. etc...
Automotive Machining, cylinder head rebuilding, engine building. Can't seem to quit #-o
econo racer
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Post by econo racer »

I built a 350 bored 40 over with flat tops used 74 cc heads-probably about 9.2 compression-used a 268 comp hi energy cam-218 dur at 50 and 454 lift-Alum intake and a holley with headers and it really has good torque. The old 268 cam seems to just about work with anything :D
want-a-be

Post by want-a-be »

I'd go with the air gap type intake.

The cam I've used, and have had very good luck with, in the engines I build for towing has a lil' more duration then whats being suggested here. 218/222 @.050 with around .445 lift and 112 LSA. If you don't like that then the 214/218 @.050 duration still staying under the .450 lift. 112 LSA. These are very drivable cams that tow very nicely.

Good valve job with a mild pocket port won't hurt ether.

Also might conside a different ignition. Maybe the MSD 6a or something like it.

The cam choice I use has picked everything up for the tow vehicles I've built for using these 2 cam numbers. Including the mileage. :wink:

Thanks, Don 8)

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Post by n2omike »

I'd build a torque 383. Pulling that much weight, the increase in displacement should allow better hill pulling without downshifting. Use one of the recommended cams or a similar Comp Xtreme, smooth the heads out a bit, install an Edelbrock carb on a dual plane intake, try to talk him into headers and a free flowing exhaust... and call it good!

Personally, I'd go with the CamKing shaft, as it does look like a good grind, and he offers a lot of good, FREE advice here.

(I'm assuming he's doing a rebuild. If he just wants to pep up his existing engine, nevermind) :)
pdq67
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Re:

Post by pdq67 »

Keith Morganstein wrote: Fri Feb 29, 2008 10:56 pm
drifter wrote:What is a mtc camshaft? who makes it?
MTC-1 is a melling cam #. (MTC = Melling Torque Cam)

It is a basic garden variety torque cam that has been around for a long time and works in those types of applications. An extra point of compression from the flat tops helps too.

This cam is sold under many brands and labels. MTC-1 is the best known. I have it in Engine-Pro brand. Just look for specs (204/214 .420 /.447)
drifter wrote:Keith have you used Engine Tec kits? Are there bearings and pistons ok for a build like this or should i go federal Mogual?
Engine Tec kits are likely o.k.

I buy from an Engine Pro warehouse that has name brand components and a few of there own label. All good parts.

You can PM me if you need more info on Engine pro kits
Right, the old, "Performer", cam!!

What are the centers and install numbers?

112/110? Or 114/112?

pdq67
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Re: Need some more hp from a 350 in a 85 suburban towing a trail

Post by pdq67 »

Towing!

Gen 1 SBC.

Might think about an old Wolverine Blue Racer W-1127 hi-cam.

Spec's:

250/184, 260/194, 107/117, .368"/.398" lift.

It is the smallest my old WBR catalog lists.

The next smallest the W-1128, is almost the same as a stock, -929 hi-cam.'

Then the, "Performer", hi-cam.

I tried accessing CC, but got bogged down, but if not mistaken, their smallest hi-cam is the, "top of the page", cam, the, "Pure Energy"??

Also from my way old catalog so they might have a smaller one now?

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Re: Need some more hp from a 350 in a 85 suburban towing a trail

Post by dfarr67 »

Put some decent heads on it to complement cam- vortec type.
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