cbr600rx7

iTrader: (12)

This set up will be going into a 87 4x4 Silverado. It’s a very mild street/trail truck that is being restored. The old 350 that we pulled of the truck had seen better days and the previous owner had hacked apart the electrical and vacuum system. They also tried to rebuild the motor using RTV and I don’t think they had a clue what a torque wrench is. The goal here is to build a strong, solid, and reliable TBI SBC on a good budget.

Truck specs 200,000 miles, 33 inch MT tires, 3.73 gears, 700R4 transmission, regular cab, 350 TBI that needs some love.

The motor is now out of the truck and we are taking it to the machine shop in the morning. I have had work done at this shop before but they do not know a lot about the TBI systems so I am looking for a little more guidance and hope to get some good feedback from people that know.

Parts we have:
Edelbrock 3704 Performer T.B.I. Intake Manifold
Edelbrock#350-3702 Performer-Plus Camshaft Kit .398''/.442'' Lift 244°/264° Adv. Duration 112LSA
Edelbrock 60859 - Edelbrock Performer Aluminum Heads 60cc with 2.02intake and 1.60 exhaust
Holley 670 CFM Throttle body
Hypertech power charger (goes from the tb to the intake)
Long tube headers (will be switching to short tubes with a y pipe for the 02 sensor)
Adjustable Fuel pressure Regulator and gauge

Full rebuild of bottom end and possibly considering going to at 383. Trying to keep compression pump gas friendly so thinking 9.25 to 1.

Truck currently has long tube headers and true dual exhaust but only has one 02 sensor. I am considering going with short tubes and building a 3 inch y pipe so it can read correctly.

I also understand that the truck will need some tuning so I am considering TBI chips unless someone has other recommendations.

Any advice or guidance is welcome.

bufmatmuslepants

iTrader: (3)

Wrong section. But the tbi is like a 2 barrel. You are completely wasting your time spending $6000 on a tbi setup. For a shitload less money you could do a 5.3 4l60e swap and make 300hp out of the box, more than all that edelbrock bullshit will give you on that tbi system. Throw 243 heads and a cam in that 5.3 and you will wipe the floor with any 383 tbi motor.


PLEASE PLEASE PLEASE plan your build before dropping it off at the machine shop and wasting all that money.

skinumback

iTrader: (1)

The TBI has air flow issues cause of the two barrell design, it has fuel issues cause of the only two injectors, so its never going to make a lot of power. now, that being said it is very reliable and can be upgraded some. If it were me i would do a stock rebuild with vortec heads and the tbi vortec manifold, id raise the compression up to aabout 9.5:1 and put in a high torque hyd roller cam and roller rockers. I would use the stock gm tbi with a adjustable fuel pressure regulator turned up to about 15 psi, a 1&5/8 set of full leagth headers and a 2.5 or 3" exhaust. then have a reputable chip burner make a chip for that combo. this should make a honest 300 hp at flywheel and 375 ft lb of torque, and be matinence free for years and years.

Ed Wright

iTrader: (1)

That's about right. I do chips for those all the time. I'm in Oklahoma, about every cowboy around here has a pickup. LOL
What I have found works best are stock '96/'00 350" Vortec heads, which can be bought very reasonably from the Chevy dealer parts dept, along with a small cam. I would use nothing bigger than about 206-212 @ .050". Put that 670 CFM Holley TBI on eBay where it belongs. Most are junk, with a very high failure rate. No more than 9.5-1 compression. It's never going to be anywhere as fast as a 4bl carb, I don't care what CFM rating. The stock TBI is fine. You can get higher CFM modified factory TBI units from Turbo City in southern CA. Near LA, I believe. Nice pieces, bored out for larger throttle blades. I don't remember the CFM rating, but I have several customers using them. I don't know of a single problem.
If somebody wants a crate engine the 330 hp GM works fine with a TBI, as does the HT383". Neither one will make the advertised power ratings with a TBI, but perform as well as anything your going to build.

cbr600rx7

iTrader: (12)

Thanks for the advice. We ended up bringing the build back down to earth and got some good advice from tbiparts and tbichips.

I don’t have the cam specs in front of me but they are something like 204/214 and a 112LSA. We are going to run a ported 350 TB with 65lb injectors set to 13-14 psi and TPI fuel pumps out of a newer vette. Manifold will still be the edelbrock and compression will be right around 9.3 to one on a 355 and of course we will be running long tubes on this set up. I was able to convice the owner to back off and go with a more mild set up and invest the money into other parts of the truck like the tired 700R4.