SulphurDave

I know this is probably the millionth thread on this subject but please bare with me, I'd like my own thread. BTW I have browsed the forum but I'd like some answers directed more toward my situation. I'm no newb to cars/trucks or motors in general but I still have a lot to learn.

Here's my story: My father bought a 1984 GMC P/U Short Wheel Base, 305 V8 700R4 Transmission way back in 1984 brand new and has had it every since. It has been in our family for 22 years now. It was the first vehicle I drove when I got my license at age 16 (I'm 26 now) before I bought my own truck later on. It was his work truck all this time so the truck has seen its better days. In the meantime I have been into forced induction 4 cyl cars which was always way out of league because he's real old school when it comes to hot rods. He's had a couple of 69 Camaro Z28s back in the day in his younger days so he was into old school carb'ed V8s.

The reason I keep saying "was" is because my Father just passed away a couple of months ago of a sudden massive heart attack which was a total shocker to EVERYONE because he was in such great health and never complained of anything prior. So needless to say I sort of acquired the truck from my Mother to keep it running and to take care of it. My first intention was to totally rebuild it frame up with a huge race prepped V8 and turn it into a drag truck but it would definately get into my other project turbo race car and I'm sure my Mother wouldn't want me to tear the truck up and be unrecognizeable. So here's my plans:

Clean up the interior which I have already started on, change out the wrecked bed (possibly a step side bed?), smooth the whole thing out and prime it for now and eventually paint it back to stock, lower it with old school wide offset wheels/tires and rebuild the motor/transmission. The motor rebuild is where I would need help with parts/specs etc. I'm not going to go with anything radical but I do want more muscle out of the little 305 as it will be a daily driver. I do want to build it with high performance parts though such as new heads, mild rumbly cam, a new crank to punch it out 327, intake manifold, bigger carb, headers, exhaust, etc. etc. I really want to just wake it up not run 10s or anything. I'm not interested in dropping in a 350 although it would probably net me better gains. I really would like to stick with the original motor. So I need to just get a good run down of parts that would complete the package that I want. I would pull a boat with it or a trailer with my car on it that's about it. Something my Mother would appreciate, something my Father would have liked to have & something that I would enjoy driving. Thanks in advance for any help. Here's some pics of the truck. Be nice... she's old and needs some TLC.

:::UPDATED::: 2/24/08
New video of roughly 1/8 mile run through 1st and 2nd gear (post #51)

SulphurDave

16 views... no replies. Great site.

orange88

iTrader: (1)

so what do you wanna know?

Camaro396

iTrader: (14)

well first of all how much are you looking to spend on this motor? give me a price budget and ill set u up with a list of some nice parts..

SulphurDave

Well is it worth the effort to stroke it to a 327? Do you have to change out rods/pistons etc? how much work is involved with this build up? What parts would I need to wake it up some? Better flowing heads, a mild cam, intake manifold, bigger carb, headers, exhaust, etc. etc. I mean what am I looking at as far as, is it worth it and how much dough are we talking? Take consideration that this will not be a 1/4 mile drag truck just a daily driven muscle truck to some extent. What would $1k do? What would $1500 do? What about $2k? (that would be way overboard on just the motor) because I also want to fix the body and paint the truck. I want a reliable setup that will last another 100k miles if it doesn't rust to the ground by then. Thanks for the help guys.

91Z28

If you drop in a 3.75" crank it'll be a 334. 327s have a 4" bore and your 305 has a 3.76" bore, so you're not going to drop in a production stroke crank and get a 327.

Camaro396

iTrader: (14)

you can stroke the 305 to a 335 go to www.powerhouseperformance.com they have the kits avalivble with the new crank, pistons, rods, bearings and what not, and a decent set of heads is going to be around 800.00 dollars and a good set is going to be around 2000.00 so its all up to your budget..

SulphurDave

good info.


considering all of the above mentioned parts what would that net me with hp figureatively speaking?

what $800 heads are you talking about? what about the intake manifold & carb?

Camaro396

iTrader: (14)

You can crack open a Jegs catolog and find a decent set of cast heads for around that price. Aluminum heads would be ALOT nicer, but ALOT more expensive. Intake and Cam depend on what heads you go with, everything has to work together. I would say no bigger than a 650 4BBL carburator.

3rdgenguy

iTrader: (1)

u can pick up a set of trick flow for around a grand

-db-

I just got rid of my '84 C10 Custom 350/4-speed. I know you say you want to keep the 305 but these trucks really need at least a 350. They're not light trucks and I remember wishing I had a 383 instead of the mild 350 (RPM intake, Magnum stick, headers, the normal stuff...) while hauling a bed full of everything I owned at the time moving from MI to CA a few years back. You're talking about towing a boat so you need some torque. For just a few bucks more than you'd spend hopping up that 305 you could get a 350 or 383 crate engine and make a lot more power that would still give you good mileage and durability.

Good luck with whatever you decide. Those are great trucks.

SulphurDave

I realize that the 350 would be the better route. It's just the fact that the 305 has been in there since it was brand new and my Dad took care of it.. I would hate to take it out. It's amazing as it is with it just still running. I'm not sure what to do. All I know is that I want to keep it running and keep it driving on the road and use it for taking my kids to beaches, camp sites & towing a 15' alum. boat to go fishing etc. I was just hoping I could get some muscle out of it while doing so.

CTSV05

Well, here are my thoughts, as I've said before, I like the 305, the factory killed them from the start, they just need to breathe.

Leave the stroke alone, do a good quality rebuild, be sure to add good fasteners, esp the rod bolts.

Try to find a set of 305 Z28 heads with the small chamber and 1.94 valves. have a mild street port and gasket match, be conservative on the porting, as you'll want to keep port velocity up. You'll need premium fuel, but its worth it.

I would stay with a more conventional hi-po dual plane, keeping the drivability issue, and the fact you are going to want the powerband in the 2500-4500 range, in mind.

I would look for a cam with no more than 220* @ .050. Preferrably in the 210-215 range. Get the most lift you can find with the dur. specs there. Also, I would go with a 1.6 rocker too. 305s like lift, but too much duration will kill your towing.

A good Quadrajunk will be a great carb, as they do really well for daily use. But, it must be a QUALITY rebuild, or new. Keep this in mind if you choose that when buying an intake.

I would go with a conv. rated at about 1000 over stock, again, too much and your towing becomes a problem.

This should bump your 305s power up a significant amount, whille keeping some economy and towing use in mind.

duffman

i would get an exhaust, hei distributor, proform or accel i think is alot cheaper than msd, intake manifold, carb, k&n filter, cam, and maybe some higher compression forged aluminuim pistons, and head work. then just line-x the bed, slap on some wheels, and insall a footprint gas petal. it would really be better if you could just get a 350 or 383 but if you want to keep that engine and get some cheap realiable power that should do it.

SulphurDave

Thanks CTSV05... now that's the kind of info I'm needing. Thanks to everyone. It sounds like I can wake that little 305 up a little. I'll continue to do more research and talk around with buddies. I'll update this thread as I continue to build it up.

SulphurDave

i finally finished making the interior look a little nicer. now i need a bed, prime/paint, and i'm gonna tear into the motor to some degree. who knows what i'll do... might just go ahead and do the 350 thing.

Camaro396

iTrader: (14)

lookin real nice, big diffrence, but yeahh youd prolly be alot better off with a 350..

SulphurDave

thanks. i just found out that one of my buddies is selling the motor out of his Nova because a tree fell on it and the chassis is no good. the motor went untouched though. this was a nova drag racing car. it has a fully built 383 and built turbo 350 tranny & 5000 stall (i know its high). it put down close to 400 whp. just for ***** & giggles if that motor was in my truck with stock rear end gear what would it run in the 1/4 mile figureatively speaking (good launch etc. etc.)?? just curious because im pretty sure he would sell me the motor. would the truck be streetable? i dont know what cam is in it but it's pretty "lopey". i can find out details if that's necessary.

04LS1GTO

I am in the same boat except my truck is a 84' 4x4 w/305. This is the route I am going

Parts Price
383 stroker kit $745.00
machine work ?? $500.00
edelbrock intake $240.00
comp cam kit 12-239-3 $170.00
oil pump $25.00
bolt kit $75.00
vortec heads $520.00
head bolts $50.00
roller rockers $260.00
pushrods $30.00
speed demon 650 carb $400.00
timing chain $35.00
water pump $65.00

Total $3,115.00

04LS1GTO

get that motor and swap the cam, lifters, converter for something more streetable