350 Build

[MOBS]

I've only had this information second-hand, but someone I know tested the 350 tbi in stock configuration(injectors mounted without any spacers) and the flowbench gave them like ~480cfm. I've also had the 350/290 once before, it was the model with 290hp/355lb-ft tq and the carb was the 750cfm quadrajet, unless they've changed the configuration, your's should have the straight-plug 64cc chambers. I'm just wanting you to understand you will be limited in future upgrades to that engine with the stock 350 tbi. You could always have it ported, or better yet, run a 454 tbi with the 350 injector pod; I think the edelbrock tbi manifold can be optioned to have the ports enlarged to clear the 454 tbi butterfly valves. Now when doing that, it's best to ofcourse get a custom tune, a tad larger injectors(or just increase your pressure 3-4 psi at a time till you hit the sweet spot). Oh there's a bunch of things to consider, if ya need any help with the aspiration, just holler.

 

[93Chevy_1500]

I will be ordering the 350/290 in a few weeks. Ive got to do a timing belt and brakes on my Honda before I start a new project. Im going to be buying a tbi motor (hopefully another truck) for all the pulleys, tbi, intake, and all the other extra parts. I have a few more questions though will my v6 starter work? (its 3 months old) and the alternators are the same? (3 months old as well).

 

[93Chevy_1500]

I've only had this information second-hand, but someone I know tested the 350 tbi in stock configuration(injectors mounted without any spacers) and the flowbench gave them like ~480cfm. I've also had the 350/290 once before, it was the model with 290hp/355lb-ft tq and the carb was the 750cfm quadrajet, unless they've changed the configuration, your's should have the straight-plug 64cc chambers. I'm just wanting you to understand you will be limited in future upgrades to that engine with the stock 350 tbi. You could always have it ported, or better yet, run a 454 tbi with the 350 injector pod; I think the edelbrock tbi manifold can be optioned to have the ports enlarged to clear the 454 tbi butterfly valves. Now when doing that, it's best to ofcourse get a custom tune, a tad larger injectors(or just increase your pressure 3-4 psi at a time till you hit the sweet spot). Oh there's a bunch of things to consider, if ya need any help with the aspiration, just holler.

They must have changed the specs. Heres the motor http://www.jegs.com/p/GM-Performance/GM-Performance-Parts-350-Engine-Package/755609/10002/-1

 

[dirtridinz71]

I may be wrong but a TBI intake will not bolt up to that motor, you will need a carb intake with an adaptor plate for the throttle body. The 4 center bolts holes on the older style blocks are on different angles.

 

[Tinbender59]

I may be wrong but a TBI intake will not bolt up to that motor, you will need a carb intake with an adaptor plate for the throttle body. The 4 center bolts holes on the older style blocks are on different angles.

you are corect!! I ordered a vortec motor for my '99 burb $2500. direct drop in. if I were you I would look into a vortec, "they run better" and get better MPG's than the older stuff. but hay I am putting a WS6 LT1 in my 97 k1500. !!!!!!

 

[MOBS]

Yeah, to run tbi, you'll need the edelbrock tbi manifold that's made to fit the old style heads....or vortec heads if you were to go with a vortec engine(vortec heads basically are new age camel hump heads).

Here's an idea about how crappy the tbi heads are....I had a performance shop test airflow on my yukon right before selling it and at 5,000 rpm it was only pulling ~430cfm. My 357 with the 268H cam and 041 heads pulls 515 at the same rpm, so you'll REALLY be getting an upgrade with just the heads from that 290horse motor.

WoW, they DID change the specs: 76 heads with 194/150 valves........cam looks close to the same, but those heads....where's the "cringe" smiley face? Those heads aren't bad, definitely better than the tbi heads by far, mine had the 64 heads with 194/160 valves and the cam was a 226/226 with 450/450 lift. So yeah, only 4 more duration on both sides, but your's has .010 more exh lift; they're about the same. When ya get it, give me the head numbers, I'm curious as to what they are.

 

[93Chevy_1500]

Yeah, to run tbi, you'll need the edelbrock tbi manifold that's made to fit the old style heads....or vortec heads if you were to go with a vortec engine(vortec heads basically are new age camel hump heads).

Here's an idea about how crappy the tbi heads are....I had a performance shop test airflow on my yukon right before selling it and at 5,000 rpm it was only pulling ~430cfm. My 357 with the 268H cam and 041 heads pulls 515 at the same rpm, so you'll REALLY be getting an upgrade with just the heads from that 290horse motor.

I plan to run an the aftermarket vortec heads in the future but right now they are out of my budget. Who knows by the time I get the motor some might have come along. So I will need a carb intake with an adpater plate to run the tbi. Thats no big deal. Thanks for the help.

 

[MOBS]

Ummm yeah pretty much, or the edelbrock tbi-to-standard head manifold....but for the meantime, a quadrajet carb intake with adapter plate should work fine. Some people are against adapter plates, but it's mostly bad when trying to adapt a 4bbl to a 4bbl(quadrajet intake to square bore carb or vice versa)....with the tbi up-top a quadrajet or square bore intake, the adapter plate will be the least of your worries when it comes to disruption of airflow....because your tbi will be what's bottlenecking the airflow mostly. If you can find one, I'd suggest the tbi be adapted to a square bore intake, and the best configuration you'll actually get with an adapted intake is one built like the performer rpm model that's dual plane with the opened bridge(allows crossing airflow) also known as an "AirGap" manifold. I wouldn't suggest buying one new though, that would cut heavily into your vortec savings. Keep an eye out on ebay for both a used intake and the heads.

 

[DRAGGIN95]

Also you can run your original intake but you have you reangle the center 4 bolt's, 2 on each side, I have done this multiple times with no problem's and I have one in my driveway that I did that to year's ago with no problem's. 1955-1986 SBC's had 6 intake bolt's on each side of the intake that all went in at the same angle, 1987-1995 SBC's also have 6 bolt's per side of intake, but the center 2 bolt's on each side go in at a slightly different angle, so if you want to put the newer intake on the older head's you have to take a drill and 3/8 bit and slightly reangle the holes in the itake to make them match the other holes on each end, it's very easy to do and takes about 15 mins, also all of the port's match up just fine. This does not apply to Vortec head's, they are entirely different.

 

[MOBS]

Oh hey, there ya go....and while the intake is apart, you can do some "ahem" grinding on it....*wink*