305 swap question

[Stewart G Griffin]

Please describe the swap in great detail as i found there was little to no room to work with.

[Stewart G Griffin]

OK, i did a little investigating and i came up with GM Part# 464607.  This pan has the stick going directly into the pan on the drivers side and they supposedly came in malibus only (?).  This should be what you need; i may look into myself if time permits.

[SUX2BU99]

I have a driver-side dipstick on mine, and I see the end has been cut off a little below the top FULL dot. Can I just any SBC dipstick in there and not worry about it hitting the oil pump or soemthing? I'm not sure why the dipstick was cut off but it concerns me a little.

[dumbucket1]

I have the knocking motor out. I'm researching what it would take to put a 400 in it instead of the good 305. I would like to keep the tbi.

[VileZambonie]

Not much other than a 400! Good swap!

[Stewart G Griffin]

I have a driver-side dipstick on mine, and I see the end has been cut off a little below the top FULL dot. Can I just any SBC dipstick in there and not worry about it hitting the oil pump or soemthing? I'm not sure why the dipstick was cut off but it concerns me a little.

i'll get back to you on that one (as if i would know).

[dumbucket1]

Ok I decided to use the good 305 and save the 400 for another project. Couple questions though. Are the tbi heads worth the trouble of swapping onto the 79 motor? And after pulling a valve cover on the 79 motor I discovered roller tipped rockers with 1.6 stamped on them. What exactly do those do and will they mess with the trucks computer?

[Stewart G Griffin]

1)RE: tbi heads:  probably


2) RE: 1.6 rockers:  probably not.  Why not just ditch the computer?  My bad---i just re-read your original post.

Please keep us updated and hopefully discuss any little nuance you feel is important(as i'm in the midst of swapping a pre-80 305 also);  i especially am interested in your dipstick solution;  You could try that part# recommendation above.

3) Sux, i will, hopefully, get back to you, or maybe not.

[eventhorizon66]

Ok I decided to use the good 305 and save the 400 for another project. Couple questions though. Are the tbi heads worth the trouble of swapping onto the 79 motor? And after pulling a valve cover on the 79 motor I discovered roller tipped rockers with 1.6 stamped on them. What exactly do those do and will they mess with the trucks computer?

Roller tipped rockers are a good idea for any OHV engine.  The 1.6 rocker simply multiplies the cam lift a bit more over 1.5:1 rockers (and also increases valve velocity).  Unless the cam is already a bit too big for the TBI to handle, I'd say no they won't cause any problems.  But you should verify that the rocker tip sweeps across the CENTER of the valve tip.  Most people think that 1.6:1 rockers are a simple bolt on affair (the major magazines are mostly to blame).  The pushrod length may need to be changed.

Also, according to the teachings of the great David Vizard (I'm sure you guys are sick of me mentioning him, LOL), unless you are certain that 1.6 rockers on the exhaust will achieve the results you want, stick with 1.5:1 rockers.  You reap most of the gain from high ratio rockers, with minimal drawback, by using them on the intake only.  The exhaust side is more sensitive to changes in duration rather than changes in lift.