Bang for the buck...goodwrench 350

[Carnut1]

I should really work on my reading comprehension skills. I missed the part you have him changing the rear gears to something more appropriate for towing. Those 2.73 gears are good for going downhill and that's about it.

Head swap would make the most sense. Cam/lifter package to compliment the heads would be ideal. Then of course a nice free flowing exhaust. I'm very good at spending other people's money. What kind of budget does he have left?

Roughly $400. The gear swap is pretty expensive (especially around here) and ate up most of the meager budget, but I think gears is going to be by far the most effective thing he can do.

I did a set of 434 heads with 1.94/1.5 combo for a truck that needed to haul heavy loads. They worked well, they have very small ports. Some are heavy casting with 70cc chamber. Thanks, Charlie

[fastblackracing]

Gears 3.73, Heads,headers, 1.6 intake rockers, cam in that order for biggest results.....although i understand the cam being cheaper and easier to do than the heads.....

If you do the cam try to get something with a really tight lobe center angle, I think the factory
cam was on a 112 IIRC, and of course re-working the advance curve will provide a nice improvement.
I would think something along the lines of a 206/206 on a 106-108lsa with 450-470 lift would be good.

Quadra jet i assume?
Also if you could set up the air cleaner to get its air from outside the engine compartment
could result in 20-40 degree cooler intake air temps.

Also do not over look the cooling system.

Chevrolet Performance GM Goodwrench 350ci Crate Engine 195 HP (Can produce up to 260 HP)
Chevrolet Performance 12681429 Details
Crate Engine
Specifications
4-bolt main with a 2-piece rear main seal
Nodular iron crankshaft
4.000'' bore x 3.480'' stroke
Internal balance
LT1/LT4 powdered metal connecting rods
Cast aluminum pistons (dished)
8.5:1 compression ratio
Hydraulic flat tappet cam (.383"/.401" Lift, 194 / 202 Duration @ .050", and 112° lobe separation)
Cast iron cylinder heads with 76cc chambers
1.940'' Intake / 1.500'' Exhaust valves
1.250'' diameter valve springs
1.5:1 ratio rocker arms
3/8'' pressed-in rocker studs
Block is compatible with left or right side oil dipstick (plugs for unused side included)
4-quart oil pan
Oil pump, oil pump pickup and oil pump drive shaft installed
Includes timing tabs for a 6-3/4" or an 8" balancer (balancer not included)
Recommended spark plug: 14mm thread, .460" reach, 5/8" hex, tapered seat, projected tip (AC Delco p/n 065-R45TS, Autolite p/n 417-144)
Not Intended for Marine Use
Requires p/n 809-19299222 or p/n 555-23605 Oil filter adapter (not included)
Not Intended for Marine Use
No core charge

Major Components NOT Included:

[Keith Morganstein]

I should really work on my reading comprehension skills. I missed the part you have him changing the rear gears to something more appropriate for towing. Those 2.73 gears are good for going downhill and that's about it.

Head swap would make the most sense. Cam/lifter package to compliment the heads would be ideal. Then of course a nice free flowing exhaust. I'm very good at spending other people's money. What kind of budget does he have left?

Roughly $400. The gear swap is pretty expensive (especially around here) and ate up most of the meager budget, but I think gears is going to be by far the most effective thing he can do.

A complete used rear axle is cheaper than a ring and pinion swap... if you haven’t done it yet.

[KnightEngines]

I did one of these for a boat last year:

Pulled the heads, flat milled a bit, machined for screw in studs & bolted them back down with .015" shim head gaskets to close up the quench & get some compression into it. Factory compression was a dismal 7.9:1 when I checked it! I got it up to 9:1.

I used a 213/213 on 108 cam & owner supplied 1.6/1.5 ratio rockers.
Staying with stock rockers I'd use a custom grind cam with less ex lift & 108 centres to build some torque.

Came out good for a cheap engine.

[BillK]

For the amount of money you are talking about spending I would tell him to lease a real truck for the few weeks. Will probably be a lot safer too in the mountains.

[cv67]

Like all these ideas but renting one that does the job would be his best route. No hands getting dirty, plus something new is always a plus to have.
if the guy picked up 30 or so lbs of torque is it really going to help that much (gearing too). WIll he feel like its worth it?

[F-BIRD'88]

Summit cam Sum-K00172
274-274-218-218 106lsa ***100/112 *** .450-.450
.050" valve timing 9 -29. // 41- (-3)
People report that this specific cam works very well on the 350 with 305 head swap combo.
Can advance to 100 deg in c/l.
Can use 1.6 intake rockers. Can drill and roll pin rocker studs
This gets the intake valve open at tdc at a higher lift
Where port flow is higher for power (torque)
The cr will not be excessive if the chamber is hand deshrouded a bit to say 60-62cc when ported.
(More flow too)
Use the shim gasket. Don't be shy with the porting.
Knightengines is right about the dizmull 7.8;1 cr.

Check the chamber size of your 601 heads.
They seem to vary. You do have them in hand.
Block the exhaust ports twinned egr cross over ports in these heads with thick long strips of aluminim foil balled up and jammed in these passages
The aluminum foil plugs does not need to be right flush in the ex bowls (recessed is great) but must stop twinned center ex port ex cross talk.

A must do for eddy performer intake manifold
(It gets too hot)
Use champion RV8c spark plugs. AC R42T
34° or < timing. Vac adv has to be custom dialed in under towing conditions. Do not over time when towing.
Its not the same as drag racing sprints...
Carb will need custom dialing in. A tall (wood) "combo spacer" (not open) can help. (Ducted) Cold air induction as suggested.

Headers ....

He will love the sound. Yup going to need gears.
(Not less than) 3.73 for 28" tall tires for towing.
Getting the (towing under load) rpm right is critical.
Get the truck (Hot rodded) engine rpm up where it makes TORQUE. 4.10's for this is not too much.
This specif combo creates a good torque boost right in the mid rpm range for towing power but the running engine rpm must be right (gears)(3.73-4.10)(28" tires)

The new truck rental suggestion makes a LOT of sence.
He will enjoy that....

[F-BIRD'88]

You can make your (wood) combo spacer(s)
By siamese-ing two of the 4 holes in this 4 hole style type carb spacer. Like this. Can be 4150 flange or QJet spreadbore 4 hole pattern..
The siamesed holes goes on the shallow plenum side.
You can make your own better than you can buy..
Can be 1/2" , 1/", 1.5", 2" tall as required for effect on a performer intake. A truck hoodline allows this...

[plovett]

I am not an expert on towing, but my opinion is to do the headers and better exhaust. I think it will gain power everywhere. The other biggie is lowering the gearing which he has already done.

JMO,

paulie

[F-BIRD'88]

The crate motor 76cc open chamber heads can be used for a 305 or 350 low cr street blower motor project.
Stock valves full home porting. On a stock dished or flat top piston 305 with a 144 or 177 blower and cam.
Big street power low budget simple build.
Do those crate motor heads have twinned center exh egr passages like a 305 head or single like the old 441/920/336 castings?
Any low cr 283, 305,307 ,327,350 sbc is just right.
What ever you can find, steal,borrow, donate is spot on.
The 142,144,177 roots street blowers all do sick power things to these low cr small cid engines for cheap...
Using those 76 cc crate motor heads (with full home porting) Your other friend with the Nova would love this ...
Just saying....

[F-BIRD'88]

If you build this 350 w/ported 305 heads 218/106 lsa .450" cam deal. This creates a egr effect at idle and low rpm.
You will want to recurve the hei diz for this.
It will want a lot of base idle timing 20 to 22-24 deg at idle yet want modest 34 +/- deg max wot timing.
So... Shorten the mech curve to about 10 deg travel.
Limit.. Then, use moderate tension mech adv springs to get a moderate stable mech advance curve.
Smooth , progressive mech adv maxing about 3000-3300 rpm.
Use no more WOT max mech timing than it wants needs.
32-34 deg ish. (Steady uphill Towing under load)

Then dial in the vacuum advance rate and limit as needed by drive testing.
No claim this will be 87 octane friendly.
Use 91-92-93-94 octane premimum as required...
But it will make impressive mid range torque for towing loads up hills with correct gearing.

[Truckedup]

The engine in it now will tow ok on flat ground with 3.73's running between 2500-3000 rpm, about 65 mph. I won't be the first to the top of the hill but it will make it...OP says low budget? what's low, $1000?.....If the gear swap needs to be done in a shop, pluss a tranny cooler and fluid change will burn up $500....Save the rest for gas,lol

[travis]

We both tried finding a complete rear end with 3.42’s or 3.73’s locally...found plenty with 2.73’s and 3.08’s and even one with 2.56’s lol but nothing lower. He should have the truck back this morning with the new 3.42’s in it.

He’s going to bring the truck by here later today for some tuning and a tune up and so I can change the mufflers on it, plus add the tranny cooler, check the brakes, etc. He wants to drive it a few days to see if he wants to go any further with it.

I did find a set of good used 083’s with a fresh valve job and seals for $150. Aren’t these 64-ish cc heads from TPI 350’s with 1.94/1.50 valves?

[novadude]

I think a 218/218 @ 0.050 on a 106 LSA in a 8:1 - 9:1 350 with a stock or "tow" type torque converter would be a terrible choice, especially with 2.73-3.42 gears and tall truck tires. That engine is going to be dead off idle and won't start making torque until ~2200-2500 rpm - well above the stall speed of the converter. Would work good in a hot rod with a ~2400 converter, but that is not a "tow cam". JMO.

I like the <215 deg @ 0.050, 108 LSA idea posted above.

[jeff swisher]

I have used the 252H and the 260H and the 268H and a twist on the 268H all comp masters.

Believe it or not the 268H did very well in my towing duties I had one ground on a 106LSA and used it in a 350" with .013 piston down the hole and .039" gasket ported 601 heads the chambers were stock at 53.5cc and I opened them to 58. mostly around the intake area near the sparkplug.

You do not need the 1.94 valve shrouding is terrible and you really need to kick the chamber out to take advantage of the larger valve..I end up at 61-62cc with the 1.94 and 1.50 combo in the 601 heads. Not really worth it.

I have done the 1.84-1.50 and 268H a few times in trucks and TQ is awesome You can use the Q jet iron intake with blending in the plenum and a Q jet or carter afb and get 18 MPG with no vacuum advance and a TH 350.

Like stated the timing I use is 18-22 initial and 35 total works very well 3 more HP with 38 total at the wheels in my testing.. so 35 keeps you very safe.

All my timing is in by cruise rpm which is usually 2200.
91 octane is what I use.. skip the 601 heads if you keep chamber small or want to run them without porting or if you want to run 87 octane.
They really need porting and peanut shape that chamber.

I can run 87 with mine but not with a load in tow..I could possibly with very light throttle but not my idea of a good thing.

Any head you have I say bowl port it if 76cc mill it .030 to get 72 that will really help as you know.
Usually 4 tenths in the 1/4 with bowl porting.
Makes more difference than a cam swap in my testing as far as coming out of the hole harder. Which is what a tow engine needs.

I had my best tow cam built with a 268H master the cam was ground with the intake lobe advanced like you would grind one on a 106LSA.
The intake valve closed 1 degree sooner than the 260H THEN I had the exhaust lobe pushed over to make it a 112LSA grind.

This reduced overlap and made MPG come up from 12 to 18.. the 12 was with the same masters but ground on a 106LSA.
I had to experiment you know.
Power at the wheels was the same to 5700rpm which is where peak HP was after 5700 the 112LSA cam fell off like a brick.
I did not care about that as this was an experiment on MPG and changing the exhaust lobe position only.
That 350 had 225PSI cranking pressure with the 601 heads and both cams.

It would get 18 pulling my 15 foot bayliner to the lake 160 miles away.
Much better MPG than my sons 2014 5.3 chevy truck can get. we used his and got no more than 12 MPG pulling the same boat on the same path.
I ran 3.25 rear gears and th350, tires are 235-75-15 goodyear wranglers.

My old Nova with milled and ported 76cc heads (72 after milling) and 268H would also get 18 pulling the same boat. That 268H was stock profile grind.
It had 3.08 gears and TH350 Q jet and Qjet intake.

Worst MPG ever with the 268H combo was 12 MPG pulling nearly 10,000 lbs which included the tow vehicle.

The 260H with low compression ported everything 302 ford in 6000 lb van and 3.50 gear got 17.6 MPG 2 barrel on iron intake 3" single exhaust.
Pulling loads it would get the same. No vacuum advance, timing all in by 2200 rpm. Drove it 13 years and MPG always impressed me for the brick it was.