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lightemup 11-01-2004 07:48 AM

crappy mgp
Hey guys
New here, got a question for ya

I have a 65 chevy p/u with a 327. We had to put a new tranny in it b/c the one that we bought it w/ blew up (rear seal came out leaking out all the fluid while they dragged it to the show where we bought it). We put in a TH 350, and because of the cam in the engine we had to put a 2200rpm stall converter because it wouldnt idle. The thing runs like crap on the highway and gets HORRIBLE gas mileage. It gets 10 on the highway and less in the city. Im 16 and cant afford that! So my question is should i get a new tranny? A 5 speed would be awesome...

PS it has 3.72 in the rearend.

troy-curt 11-01-2004 07:58 AM

10 isn't bad for a hotrod.

Get an overdrive or change cams.


lightemup 11-01-2004 02:51 PM

It only gets 10 on the hw...not throught stoplights. We looked at the overdrive, but thats more than a new transmission. And for the cam.....we prolly will change it if we ever rebuild the engine.

poncho62 11-01-2004 03:39 PM

If it's a 1/2 ton you should be getting better than 10..............3/4 or 1 ton, I could see 10.

Do a tune up, check to see that the choke is opening all the way.............could be a number of things.

The fact that it wouldn't idle tells a lot...............

troy-curt 11-01-2004 04:54 PM

Don't add overdrive, replace the transmission with an overdrive transmission.

10 is not bad for a hotrod.

If it has a big cam there is no telling what kind of compression or carb. and jets it has.


lightemup 11-01-2004 08:55 PM

poncho, it wouldnt idle with the stock stall converter because of the cam. its a 1/2ton

We really dont know much about the doesnt run very good. We dynoed it and it made 240hp and 260ftlbs@RW. not very impressive at all....

It was very rich so we put new jets and rods in the carb(which is too big, 750). I think that made a difference...but not much.

poncho62 11-01-2004 08:58 PM

Even with a fairly radical profile cam, it should still idle.

lightemup 11-01-2004 09:00 PM

Its pretty radical....

It would idle in neural, not drive. Every time i came up to a stop light i would have to put it in neutural.

poncho62 11-01-2004 09:02 PM

OK...that and the hi stall converter (slippage) are probably the reason for the bad mileage.

lightemup 11-01-2004 09:04 PM

Yeah, that is part of it, but also having a 3 speed tranny doesnt help at all either. Don't you think it would be much better with a tranny that had an overdrive.

Siggy_Freud 11-01-2004 09:06 PM

Yes. Worth a couple of MPG.

poncho62 11-01-2004 09:07 PM

Sure...if you want to spend the money. Why not go with a more streetable cam, will be further ahead for less money.

If you are not worried about the money, don't worry about mileage.

lightemup 11-01-2004 09:11 PM

Not changing the cam because im not gonna take the engine out and apart.

Siggy_Freud 11-02-2004 01:17 PM

Well short of changing the internals it seems the only big increase you'll see is going to be from an overdrive, and/or a MPFI system. Both of which are going to run you 1000+ bucks. You have your answers, its up to you to decide what to do with them.

ChevelleSS_LS6 11-02-2004 07:15 PM

Here's what I'd do...
1. park the truck and drive a boring economical car as a daily driver
2. save money
3. get OD tranny, 600 CFM carb, more streetable converter, and a cam designed for torque (a fairly mild cam); the 327 if I'm right is more of a midrange-hi rpm performer. Then, it should get better mpg.

750cfm is wayyy too big for a 327 unless that thing was built to kill.

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