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Discussion Starter · #1 ·
I just got my 88 chevy suburban R10 4x4 with the 5.7 litre chevy 350 tbi motor. I have a flowmaster 40 series that i plan on getting a local austin shop to weld on, infront of the drivers side rear tire. I was wondering if anyone here had experience with the Tbi motor, and what should be my next upgrade? The truck has mickey thompson 32's on it now, and I am wanting to build a mud truck,with eventually a lift kit. I am looking for any suggestions where i can start on a budget. I was thinking heads intake manifold and cam to start. I have never had a Tbi motor, mostly carb motors, and am open to advice or suggestions.
 

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Welcome to the club. Edelbrock makes a PowerPackage for your truck. It's avaible in several stages, intake,cam,heads, headers and exhaust. Check out there website.
 

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Welcome to the club Phil. I went with the GM L-31 Vortec cast iron heads on my '88 5.7. They're cheap & a good place to start. Edelbrock makes a good dual purpose cam EDL-2102, it's 204 degrees duration on the intake, 214 on the exhaust, intake lift .420", exhaust lift .442"
For serious HP for offroading/mudding you may want to go with smth a little wilder, but then you'll also want to dump the TBI & change over to a carb & different distributor if you're looking for a lot more power.
 

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So you're looking to build up a motor to push some big tires, and have power to go wheeling in the mud?

Motorwise, I'd start with your intake system. Either a kit from a vendor (KandN is a good choice) or build your own. My set up, is a homemade intake tube from the fenderwell to the air box, with the lid flipped over, and a KN Filter. Next, with more air coming, you gotta get that leaving. So a flowmaster would be a good choice, with new exhaust pipe and such. Depending on how much power you wanna make, I'd suggest headers. Long Tubes are my choice. After exhaust, I suggest ignition. MSD makes some good products. I have a MSD Coil, and MSD Plug Wires on my truck.

Vortec heads from a 1996-1998 truck would be a good upgrade also.

If your looking at going further than that, I suggest Comp Cam's 1.6 Roller Rockers, and their "Extreme 4x4" camshaft. At that point, I'd rebuild your motor, might as well if your in there. Also consider a chip or custom tune. I don't know who does custome tune for our TBI trucks, but TBIChips.com makes some good chips. They take your info from you, and burn your a custom one. Along with that, look at upgrading your transmission. Bigger stall, shift kit, and all new internals is a good upgrade also to handle not only the power, but the bigger tires.
 

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Discussion Starter · #5 ·
thanks for the advice. im not looking to go to a carb swap, cause i heard it was a pain in the ass, but i will check out edelbrock for the intake and tbi carb upgrades. One question i have is if i can get vortec heads, will they work with my stock cam, i imagine i need to buy new pushrods, and gaskets, but aside form that are they just bolt on and go?
 

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Yes Phil, the GM L-31 Vortec cast iron heads pn# 12558060 are bolt on & go. They have 170 cc intake runner volumes, 64 cc combustion chambers, intakes are 1.94" exhaust 1.50" & are the fast burn combustion chamber design. They also have the LT1 style ports, very similar to the Corvette 350 LT1 heads. They flow more than the GM Bow Tie heads pn# 10134392 as per GM. You can also buy the bare head castings but is not worth it dollar wise.
You can use them with your stock cam if you wish, but there's no problem with aftermarket cams either.
These heads came out on the 1996 pickups RPO L31
 

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If your looking for a Air filter replacements get aholda me. I'd use a TBI spacer on that old a truck. It helped my old one.
 

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Edlebrock also makes performance throttle bodies and maybe holley does to now. Definitely some $ to fork over for them but somethin to look at. Otherwise I completely agree with silveradotrailblazer and stephan!
 

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A set of crane roller rockers will free up around 20 hp.
 

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A guy I work with just got done building up his TBI 355, and he used Holly's new Thorttle Body. About 500 dollars, but he said it was worth it
 
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