Mockspeed88

I bought a 92 bird, with a lo5 truck motor in it, runs good, but it's slow.
Current mods on it as purchased
Weiland street warrior intake
Open element filter
Stock manifolds into a unknown diameter straight pipe
Block is a 638, and 193 heads, motor is not drilled and tapped for roller
I want to ditch the tbi, put a carb on it.
I'd like to put a cam in it, along with headers into a 3 inch exhaust
car has 3.42 gears in the rear with fresh rebuild 700r4

roadthrills

Aren't the 193 heads the "swirl" port style? They run out of wind at about 4500rpm. The 3:42 and 700r4 is a GREAT combo. Your block probably has bosses for the retainer and spider for a roller cam. If it were mine I would install a roller cam and some Vortec or other decent heads. Those 2 items will make a HUGE difference in the way it runs.

8t2 z-chev

I second 3.42s a good gear for general use with a t700 193s are swirl port,but not as bad as is often heard for use up to ~ 5500 on mild street engines. The truck LO5 can have dished or flat pistons,depending on capacity class of the truck it came from-possibly smaller valves on heavier duty engines too.

dmccain

iTrader: (2)

Summit K1103 or K1104 if you get a spring kit for the heads .Ofcourse swapping to Vortec heads would be great but you can get a lot more power out of the L05 with cam, exhaust, carb..etc.

midias

Swap the heads and put a roller conversion cam in it. Would need more info on what pistons are in the motor and what your final goals are before choosing the cam and heads

Fast355

iTrader: (2)

I had a couple of swirl port head engines with flat tappet cams years ago. I liked the old Crane 272H10 in them. Lunati makes an almost identical cam that works well too.

Headers, full exhaust and a cam like this one really wakes up a 305 or 350 without being too radical for junky vacuum assisted power brakes and ac. The stock swirl ports will make a lot more power than most give them credit. I am also not a fan of carb swapping. The TBI can also make a ton of power while keeping more reliability and drivability. An EBL flash and a big block TBI unit are a lot cheaper than a vastly inferior carb swap. I put a RS in the 11s with a TBI fuel injected 305.

https://www.lunatipower.com/high-eff...k-268-268.html

Schurkey

Did they use the correct intake gaskets? The TBI manifold uses "special" gaskets that don't have a functional coolant hole at the rear. A steam port rather than the open hole. You would NOT want those with a non-TBI manifold.


There is no "L" in Weiand.

Probably a mistake.

Headers, high-flow catalyst, and larger-diameter mandrel-bent exhaust tubes into and out-of your favorite muffler. "I" would use a large-diameter single exhaust rather than screwing around with "dual" exhaust.

The carb is a step backwards. The TBI cams are exceptionally weak.

Roller cam in a non-roller block will be expensive. Better-off getting a different core engine with OEM roller provisions.

Vortec heads will all but eliminate any chance of using EGR; it's possible but really, really inconvenient. Also, he'd have to drill the right cylinder head (I'd drill both heads so it doesn't matter which head gets installed on which bank) for coolant bypass provisions on the TBI block; and most Vortec blocks aren't drilled, either--so no coolant bypass even if the hole is popped into the cylinder head. SOME Vortec blocks do have the bypass holes drilled; and those blocks often have 4-bolt mains and fuel pump provisions also.

"Car" L05s (Caprice, Roadmaster, etc.) could have flat-top pistons. NONE of the trucks had flat-tops, but the heavier trucks could have bigger dishes than the half-tons. The difference between the "car" flat-tops and the half-ton dish pistons was approx. 1/4 point of compression ratio--9.2 vs. 9.4.

Thank you.
Downside is the difficulty in tuning the TBI computer. There ARE solutions, though.

8t2 z-chev

i think my 1991 G30 box truck has the deep dish pistons ~8,5 CR 190 hp

Fast355

iTrader: (2)

18cc dished should be around 8.75:1, often quoted as 8.8:1. Some claim the heads are 76cc, even Mortec has them published wrong. 191, 193 and 810 swirl ports are all ~65cc. The 18cc dished pistons have a valve relief similar in shape to a claw foot bathtub in addition to the normal dish. The normal 9.3:1 12cc dished piston has 4 eyebrows for valve reliefs. The flat tops have 4 eyebrows with 6cc worth of relief, they are 9.6:1. That one should be 180 hp and 300 tq. GM 929 equivalent flat tappet cam. Same cam the 300 HP 327s and 350s ran. The cam is not that weak for truck things, although there are other grinds that will perk it up alot.

8t2 z-chev

I thought the G30 had a cam similar to a 929 since it sounds about the same as my 350 '73 1 ton dually that engine has 993s with small 1,72 intake valves The G30 has a very heavy duty cooling system with big 4-core radiator: oil cooler in left tank,tranny cooler in right tank.

Fast355

iTrader: (2)

I forget the part number, but it is the supercession for the 929 cam. The newer part number is the same part number used in a LU3 Crossfire 305 and GM Heritage has the full specifications in their Camaro information package for it.

I have an aluminum dual core replacement that is dimensionally the same as your older 4 core in my 87 G20 with a ~380 hp L31 350 in it. Radiator manufacturers claim the dual core design sheds even more heat because the larger tubes have more surface area. Runs cool as can be with an 11 bladed plastic fan. I ended up using replacement oil cooler hoses for a 99 Tahoe and they fit pretty well. The van ones are unobtanium now.

I converted to the L31 accessory brackets and accessories. The TBI PS pump bolted right on the vortec bracket. I swapped to a 145a AD244 alternator and upgraded some of the wiring from that crappy junction post behind the battery. Proflow 4 injection with a new Vortec pump on a new sending unit in a new tank. Upgraded from the 22 gallon tank to the 33 since I was buying new components anyway and it only required another $15 in new mounting straps. The 33 gallon tank was a few $ less so it was a near wash. Gave the old pig a new lease on life. The Hooker 2.5" manifolds fit like a glove, but I wish I had gone with headers instead. One of the things I actually like on this 87 is it has the 3L80 aka Turbo 400 with a TH350 output shaft and a 3.08 gear for screaming down the interstate.



https://youtube.com/shorts/q6WOUPrYwDg?si=C0ubl_LuZDWRqxgF

8t2 z-chev

Noted that '99 Tahoe oil cooler lines fit .I saw the fan in the AC post-i have a couple of those in spares stash,1995.5- 2004 S-10 4.3. my G30 box truck has the 4l80E-one of the first of that transmission.