K10 Project

[TSTONE]

Some of you probably already saw i put a dual exhaust kit on. Ordered it from LMC and used aerochambers instead of the supplied mufflers. I'm still working on perfecting the hanger and fit situation but for what i have invested im pretty happy with it so far. I want to try to add an h-pipe and i am probably going to cut/relocate the tailpipes and add tips. Right now i think they are too close to the tire and directly in the way of where a mud flap would be. But anyway, the little 305 is definitely happier now that it can breathe.

I'm still trying to figure out the rattling in the transmission. I have it narrowed down to either a throwout bearing rattle (not the bearing itself but a worn clutch fork), or an input bearing. Hoping its the first.

That had to be the weakest video ive seen in a long time and what the hell was that at the end???

[JoeliusZ28]

Its just a snapchat clip and appears youtube reduce the quality of it.

[JoeliusZ28]

Figured this thread is due for an update. Its kind of been forever.


First of all, after pulling the trans out a second time, replacing the clutch and some seals (and creating more problems with those in the process ) I figured out the noise its been making has been 100% spark knock. This 305 has proven to be one fussy SOB in regards to the timing it wants. (possibly fuel as well but i haven't learned how to tinker with carbs enough yet).



Second, I also finished off the exhaust much nicer now with upgraded hangers and exhaust tips. Photos attached.


That pretty much brings us up to speed with where im at with the truck. For the last 6 months I have been trying to decide what to do with it and I am all over the place. For the next year, the truck is going to stay as is because i want to focus on other things for a while. A couple months ago i would have told you I 100% set on selling this truck and trading up to a K30, mainly because i don't want to hurt the originality of this one. But the other side of my brain is saying "theres nothing nostalgic about a 305 anyway, lets swap in a goodwrench 350 crate engine with a warranty, add a fitech fuel injection kit and *enjoy* the truck".

The 305, as it currently is doesn't have anything specfically wrong with it. It sounds great and runs reliably as a cruiser but I would hesitate to say it runs 'well.' It certainly is not a performer and dialing the timing (and fuel) to get it run right has been an exercise in futility so far. I spent many hours on distributor configuration and modification last summer such that i had it running "perfect" and as soon as i put a trailer behind it and got some temp in the engine it was right back to rocks in a coffee can and i had to pull an absurd amount of timing out of it to keep it driveable with the load behind it. and retarding that much timing turns it into a slug. Its a lot of drama for a 160hp engine even having the help of an oversized radiator and cooler thermostat.

I've also debated getting a fitech and new distributor for the 305 as i believe even that would make a night and day difference, but the goodwrench 350 makes some impressive numbers for the cost. So we'll see.

For this summer I plan on finishing a few more cosmetic details and enjoying the truck as she is I've been driving it every chance i can get on nice days because its still a fun truck!!

[MP81]

The exhaust looks great in person, such an improvement over stock.

And whatever it is, be it the distributor or the carb, it really does not like consistency one bit. Did the distributor lock finally decide to stay in place? I can't recall.

[JoeliusZ28]

Yes, the second advance lockout kit (MSD part) stays in place unlike the first one. That improved the situation drastically. I guess to put it simpler my frustrationis that the heads on this engine don't seem to cool worth a crap. So when you put a small trailer behind it and run it down a highway for 10 miles, you start out ok but then the combustion chambers get heat soaked and suddenly the fuel/timing requirements are different than they were when you started. Even though the temp reading on the gauge hasn't changed at all.

Just cruising around on the other hand? Never a problem.

[MP81]

That's weird...the heat in the heads should definitely be reflected by an increase in the temp reading...

[JoeliusZ28]

The iron castings are so thick (and also restrictive) on a 305 that that isn't the case. Its a problem I've never had with any of the other GM v8s Ive tuned. Just an all together underwhelming example of GM smog engineering that should have never existed. I can imagine a lot of people bought K20s in the 80s just to avoid the 305.

[MP81]

If you were set on keeping the 305 (like I am, until I go LS), I'd suggest the Trick Flow aluminum heads (specifically the set actually made for small bores), but at that point with your plans, I'd say it'd make more sense to swap up to the 350.

[JoeliusZ28]

I just don't want to bastardize a truck that's survived 34 years with original everything. But I also think the truck would be worth more, and more enjoyable with an injected period correct crate 350.

[MP81]

I absolutely sympathize about not wanting to mess up the originality, but I also agree with what you said in your earlier post - it's a 305. Most people would probably prefer it have a healthy-running 350 than the original 305 that runs okay most of the time.

And ultimately, if it makes you enjoy driving the truck a whole lot more over "dealing with" the 305...isn't that what matters most?

[JoeliusZ28]

Yes. and i think thats what it comes down to. I was going to trade up for a 454 K30... but I really don't need 500hp

Part of what is changing my mind is i helped my cousin put a Fitech on a 77 dodge D200 with a 360 a few weekends back (low compression california smog 2barrel). With just an edelbrock intake, headers, and the fitech that engine went from a complete turd to a pretty solid runner. Pretty sure we added close to 100hp with just those simple changes.

[MP81]

As much faith as I have in the QJet, I wouldn't mind switching to an "on-top" fuel injection system either. Given I want to keep the 305, but do some...things...to it, prior to the LS down the road, I'm not sure if I want to mess with tweaking the carb, and still having that weird idle behavior that it gets, or just go with something that won't give me issues ever.

[JoeliusZ28]

The only thing i'll miss about the q-jet is that awesome howl it makes. And an EFI throttle body probably makes some similar noises anyway.

[MP81]

They should (if they don't already) make an EFI throttle body with as asymetrical primaries/secondaries as the Qjet has. That would certainly help that. Because, it definitely does make some killer noise.

[JoeliusZ28]

The fitech is kind of opposite of the typical four barrel setup. Symmetric butterflies and it doesnt have "secondaries" - all four butterflies open together at all throttle positions. It probably makes a similar noise at WOT, but I couldnt tell at the time because the 360 still had open headers on it