Engine Build Plan
[COLOR=#141414][FONT=Tahoma]So the sbc350 went to the engine shop today...we are putting together a build plan and am contemplating some build ideas. I am not looking for a big hp, high rpm motor - its an old willys and will be a run-a-bout and mild wheeler - low end torque and smooth power band up to 3500 rpm is really the goal. In my discussion with the engine builder, I am considering some small additional expense items that would make a nice improvement of a completely stock build.[/FONT][/COLOR]
[COLOR=#141414][FONT=Tahoma]Heads: The GM factory 882 iron heads I have are pretty much a (below?) average, ho-hum, low compression head used commonly on truck 350s. The shop can obviously do a complete rebuild, valve grind, valve seats etc but wanted me to consider some other options:[/FONT][/COLOR]
[COLOR=#141414][FONT=Tahoma]*For an additional $200, a set of rebuilt iron Vortec heads - this would up the compression, improve and smooth out the power band in the lower rpm range and are well suited for lower lift, longer duration cam specs we are planning....trade off is it would require a different intake ($150) - probably an aftermarket aluminum performer style and that would save 20lbs or so - and that might also push me towards a new carb as well...its never just an additional $200...[/FONT][/COLOR]
*The next step would be to just go to aluminum aftermarket heads. That is an additional $600 over the original cost ($400 more than the vortec)....ALthough not required, it doesn't make sense to add the aluminum heads without replacing the cast iron intake as well, so add in another $100 plus carb etc, but over 50lbs in weight savings.[/FONT][/COLOR]
[COLOR=#141414][FONT=Tahoma]Roller Cam and lifters...This is a $900 up charge over flat tappet style....is it worth it? Seems like that really helps with longevity, but not sure how critical that is on a non DD vehicle like this. The shop that i worked with on the v6225 in the cj is also of the same opinion - they don't build flat tappet 350s anymore.[/FONT][/COLOR]
[COLOR=#141414][FONT=Tahoma]My original thoughts on this build were to keep it simple and 1970's original - partially for cost as I have iron intake and good q-jet etc, but also to keep from overbuilding the engine for this application, but at the same time, I may only get to do this once, so now is the time to do it. Anyway, i am leaning towards the vortec heads, but as that is really an additional $500+, its questionable, as I think a run of the mill, ho-hum 1970s truck 350 build is more than enough for the willys. The aluminum heads seem more than I need, and can also be added later in my own garage if so desired...and the roller cam/lifters, I just don't know what that is worth....
Re: Engine Build Plan
I have two questions:
If you increase compression, will the current starter motor have issues with the increased load (or would the starter need an upgrade $$$)?
Do you plan on keeping this vehicle - long term? I'd consider this a primary factor in cracking open the wallet. (if you sell, how much of the extra money would you get out of it?)
I have no concerns with non-roller cam for the motor. You're good with keeping oil in good condition and it's not a high demand (towing) vehicle or high miles per year vehicle. It's a 1/2 of the year weekend toy (at most).
Re: Engine Build Plan
[quote=Jim;343932]will the current starter motor[/quote]
there is no 'current starter motor'....still to purchase that....probably go with a mini, high torque motor, but shouldn't really be a issue anyway. It would only bring the compression to 9:1 or so, up from 8.5:1. Crate engine 350s run about 9.2:1 or so. The vortec heads are not so much smaller combustion chambers, but rather different shaped (kidney) that produces a faster, quicker, more efficient burn. I think I can see improved mpg...maybe?
[quote=Jim;343932]Do you plan on keeping this vehicle - long term? I'd consider this a primary factor in cracking open the wallet. (if you sell, how much of the extra money would you get out of it?)[/quote]
This has really been the big question...I am fighting the same question with the steering right now as well...I am trying to hack the old steering shaft back together with the column after having to re-route due to the new motor mount position...It would be way easier to just buy an all new set-up from the column through to the box, but the price is big. It would be way better in terms of both function and form, but what is that worth....if I sell it at some point, I pennies on the dollar back - well maybe dimes if I am lucky.
[quote=Jim;343932] It's a 1/2 of the year weekend toy (at most).[/quote]
Hopefully as its a hard top with heater etc...it will be a year round weekend toy! Actually, if we like it, the plan is to sell the tacoma and Jen's hatchback, use the willys as my DD, and get another tacoma like truck with auto that Jen would DD....but in reality, guessing the willys will never be a DD...and if it did the next engine (383 stroker) can have roller cam etc...
Re: Engine Build Plan
So I was really liking the cast iron vortec heads idea...they get great reviews for the exact uses I want. But the swap to a different intake creates possible issues with my accessory brackets, and probably requires a new carb (might be able to get an intake with combination spread/square). Anyway, kind of leaning away from that extra expense and hassle - or maybe its not but I won't know until the engine comes back and then its too late if it doesn't work out easily. So, I am open to the idea of all new aftermarket aluminum heads and intake in the gen 1 sbc style - they should work fine as exact replacement to current OEM iron stuff, but again, my budget is getting a bit tight and not sure if the design focus will be right. I am looking for a 'truck' style build with an RV type cam and low rpm usage, not 400hp at 7000 rpm. So, we'll see....the engine builder is going to dig through his pile of old iron heads and see if there is something better than the smog 882 heads I have, and see if we can work with those with full head job, valve grind and seats, a little porting etc - I kind of like this route due to the authenticity of it, and it would allow usage of my current intake and maybe even qjet carb. But he's also going to see what option I might have for low rpm torque focused aluminum heads. Hopefully later this week we'll have a plan...and while he's doing all the machine work and head work, and helping me order and get all the right matching parts etc, I will be doing final assembly, especially of the bottom end. Part of that is personal interest, part budget savings, and part is most shops won't assemble the engine for you without installing a roller cam...just too much to go wrong with break in and usage I guess, then the engine builder gets blamed. More to come...
Re: Engine Build Plan
Well...its almost time to start the engine build...I need to finish up the body work on the cj this week, then it starts....got the block and heads back from the machine shop this week, as well as all the small parts. The block was original 4.00" bore size, so now its .030 over. The shop installed the freeze plugs and cam bearing but the rest of the bottom end will be up to me.
I decided to stay with a sort of late 60's/early 70s style 4x4 build. Will try to run the non-egr 1969 cast iron intake with q-jet. Stayed with 70s style cast iron heads, but switched from the late 70's 882 casting that I had to the early 70s 993 casting which should be a small upgrade in durability as its a 'heavier casting' and maybe just a bit of low end performance....both are large 75cc chambers and open chamber 'smog' style so basically the same. OEM versions of these heads would have been matched to the early 70s non-EGR intake I am running, but these heads are aftermarket GM crate engine with the desired 'hecho in Mexico' stamp.
This head swap was an engine shop focus - I don't think there was anything wrong with the 882 heads for my purpose. Really, I am not to concerned one way or another - its not a performance build. The heads and valve seats were completely redone, new rocker studs, valves etc, but no porting or grinding in the valve area. CR will stay about the same and run on low grade pump gas. The cam is flat tappet style stock replacement as well. Its going to have plenty of power in that form, and probably enough to risk the 70 year old axles if I get a bit too rowdy as is. I just want it to be a good runner....If at some point I want some improvement, aftermarket aluminum heads, intake and or TBI are all options for improvement, and possibly a new cam....but that would be a long ways off....These old willys originally came with a F134 4cyl with 70hp gross...or the optional L6-226 with 110hp gross...this sbc350 will probably be around 190-200hp net...hopefully it blows up u-joint/driveshaft before the axles....
Anybody know how to build an old school engine in a garage? Beer and pizza await if you like....