cruising speed

[tomdalrymple]

Once i get my brakes better, speed is my next issue. I suspect my truck has a 235, not a 292. It has a hei, but otherwise looks stock. When i first got the truck it was very happy cruising at 55. Any faster required foot on the floor, and the engine noise/vibration made much faster seem not a good idea. Top speed was around 65. It was turning just under 3000 at that speed. I figured gearing would help, so I put a T5 out of a S10 in it for the overdrive. Now the truck is much smoother, much quieter, but no faster. It basically seems like it only has enough HP for 55 or so. It will still go 65 if you have a long enough straight, but the highway I drive to town is two lane, and people stack up behind me. I'm not trying to make a hot rod, I just would like to be able to stay up with traffic without killing my truck. The engine seem solid, no smoke and no oil use. So far I've only checked the timing and full throttle. Both are OK. Is this normal for this truck, or are there areas i should be checking. I haven't done a compression check, but that is next. I really would like to keep the original engine. Anything these engines really respond to? Thanks

[raycow]

What year truck do you have? Even a stock 235 should pull the truck about 80 if it is in good condition, but you wouldn't want to go that fast with stock gearing. Your T-5 takes care of the gearing issue, so I suspect an engine tuning problem.

Ray

[tomdalrymple]

The truck is a 63.

[enick72]

I would agree with Ray. I put a T5 in my truck with a 230 in my 65 and it rolls down the highway great with 3:73 rear gears. It will go as fast as I need to go for the handleing of this truck.

[collins10672]

sounds like you need a higher gear rear end for faster cruising speeds.

[Captainfab]

The last year for the 235 was 1962. So your truck could have the 230, or 292 from the factory. It could have a 250 if someone put it in there. A quick easy way to ID a 292, is by the offset motor mounts. The 230/250's have the motor mounts directly across from each other. I would recommend starting with a complete tune up (cap,rotor, plugs, plug wires, set timing) oil change and oil and fuel filter changes. If that doesn't help, take a look at the carburetor.

Originally Posted by tomdalrymple

The truck is a 63.

[kalirodding]

I have a 61 with a 235 and I cruise the highway about 65. Not sure about what rear end or gears it has though. Could go faster but I don't push it.
Posted via Mobile Device

[jocko]

tomdalrymple - any idea what your current rerarend ratio is? When you mentioned you were just under 3000 rpm at 55 (before the T5 instsall) that sounds roughly around the 3.73 area. Since the T5 smoothed things out - I'd have to agree you may have an engine issue. The engine only sees rpm, so if it's not able to get you to the 70's (at least) with a T5, then you either have incredibly deep gears (which you've essentially ruled out by your previous description of it getting smoother) or you have a tuning problem. Then again, one person's definition of smoothed out (or rough running) can vary from another's. I would have suspected some deep gears if you hadn't said you were previously at 3000 rpm at 55 (in 5th gear), so - what rpm are you at now at 55?

I'm with the Captain, a serious tune-up may hopefully uncover something. I'd pay particular attn to your timing and change all the things the Captain mentioned first.

Have you checked the parking brake? (just kidding, couldn't resist)

[tomdalrymple]

I have checked for brake drag. I do suspect i have 230, not a 292 or 235. The truck lives out in the country so i don't see it every day. With the T5 I think I remember my calculations giving me 2600 RPMs at 70. I wonder about the temperature controlled exhaust butterfly not opening fully. I've lubed it, but only seem to get about 1/4 turn of motion.
The truck mainly drives on pasture roads, and really runs good. The lack of power only shows up when driving to town on the highway. I'll try to do a compression check and maybe learn something there.

[raycow]

Originally Posted by tomdalrymple

I wonder about the temperature controlled exhaust butterfly not opening fully. I've lubed it, but only seem to get about 1/4 turn of motion.

1/4 turn or slightly less is normal for the heat valve, so yours is probably free. I am thinking you could have a timing problem, either initial, or maybe the automatic advance isn't working properly. This would be easy enough to check out with a timing light.

Ray

[Martin64]

I'd also like to suggest a fuel filter. My truck hadn't ran to it's potential since I bought it...I just wrote it off as being a 230. I even change carbs (for other reasons) and it didn't really occur to me since the truck seemed to run "fine" (for what I thought it was).