Can I make 400tq out of a TBI 350?

What says the GRM brain-trust?

I just acquired my 1993 Chevy Z71, and while 210hp @ 4000rpm and 300tq out of the TBI 350 (at only 2800rpm, compared to my dad's '04 5.3L which is 285hp@5,200 325tq@4,000).

Basically, I want to get as much twist out of the motor at as low of rpm as possible with no regard to hp for towing. Tranny is being rebuilt as we speak to handle everything :D

So, think it's possible? I sent emails out to CompCams and Isky to see what they came up with. While the factory heads are supposed to be beyond terrible, apparently that is in regards to hp, so currently (due to this being a cheap build) vortecs are off the table as again, all I care about is torque.

My current ideas are:

-basic bolt ons (intake, custom chip, y-pipe/true duals) -cam swap with new lifters and an Edelbrock TBI intake

I think the biggest gain is to be had with the cam, as the stock one just sucks from the specs.

I am not sure how much you will get out of a chip. They are EXPENSIVE (if you want something custom and can't make one yourself).

If you want it to be fairly driveable, do not do the monster huge TB mods. They effect driveability.

TBI intake is nice.

I agree the cam is going to be the biggest thing.

[rant]

tq is NOT a unit of torque!

[/rant]

I always thought torques came from a longer stroke. I know you said budget but 383 stroker kit? On second thought just find a junkyard 500 inch Caddy and stick that in there.

I'm not going to type ftpnds each time Angry, tq is much easier on the interwebs and everyone knows what it means. Plus, as an added bonus, it apparently pisses of the anal retentive types.

Forget your pills this morning?

Tq could just as easily refer to N·m as lb·ft.

back in the day long tube headers REALLY woke up my 89 tbi 350.

Watching this with interest.

Check out TBI Chips

What did you do after the long tubes? True duals?

A lot of internet wisdom states the stock y-pipe is the biggest culprit of the poor exhaust system, because it looks like this:

LOL! That can't possibly be a restrictive exhaust eh? I was thinking if I wanted to be REALLY cheap, I could just do true duals off the stock manifolds, and basically have chunk of pipe off of each manifold to a cheap turbo muffler, and then side exits behind the cab. Would probably save $100 in tube plus the additional labour (I may try to make it myself).

Edit- I'd like to keep the stock manifolds if possible because (I believe) they are part of the EGR system AND they also have something to heat incoming intake air. Now, I know that sounds dumb at first, but the problem is without the heat the TBI gets real cranky in the winter time and the truck will get about 9mpg :(

I have read through the tbichips website a lot, but his trucks are typically built for power. He talks about torque as well, but I find a lot of his info is very vague.

Oh, and I'm doing a 3" drop all the way around for better highway mpg. It'll still be more than capable when going into typical dirt fields and what not that rally locations tend to take you to.

find a 96-99 vortec long block and swap it in. the only special part you need to keep it emissions legal is a vortec TBI intake manifold that GM sells and the vortec exhaust manifolds to hook up the egr valve -or if emissions aren't an issue go cheap and use a regular vortec Performer and make a TBI adapter and run some small tube headers and good exhaust.

this might not get you 400 torques, but it will be much better than stock and make a good foundation to build on with later upgrades, with the built in advantages of the vortec heads, higher compression, and a factory roller cam being thrown in all at once..

or just swap in a 6.0 and be done with it.. i've seen them as low as $1000 on www.car-part.com and probably a few hundred more with all the accessories, ecm, and harness.

a 5.3 swap is another option that is cheaper than the 6.0 and maybe even cheaper than building the 350 you've got or the vortec swap i already mentioned, but you won't get to that magical 400 torques that your mind seems to think you need. but i can tell you from experience that even the 5.3 has plenty of oomph for most things you will do with a 1/2 ton truck.

i made a 2.5" y pipe with a flowmaster 2.5 into 3" Y and a single 3" exhaust.

the summit racing 3" single into 3" dual tailpipes exhaust was overkill on the tailpipe side but it sounded awesome and was really high quality, but this was 10 years ago. i had it on 2 trucks and still have the pipes and they have no rust on them. plus i got it on clearance there for $75 and the headers on clearance for $75 so i had my whole system front to back less the Y for $150.

vortec heads are nice. 6.0's are nice, but a stock tbi 350 should be able to tow anything you need. i pulled 10k with my dad's 2wd 90 burb last winter when my dually was down with bad clutch. the rear end was almost on the ground and i thought the tires were going to blow - the engine had no problems though.

i'd honestly find what you are going to tow and pull it to see if you need to bother with anything. the 94 K1500 burb i just bought is the same basic truck that you picked up, and i won't be doing a darn thing to it.

Well basically, the truck will be used strictly for towing at its max gvcw (through mountains). I think the truck is rated to tow 6600pounds(?), and you have to figure open deck 18' trailer (2000#), rally car (3500#), spare rally tires/rims (50# each, 5 to 10 extra, 500#), tools (300#), fuel (150#), crew (minimum 400#).

Hey, I'm already at the max rating and there is probably more I can think of

I've done a lot of towing. My father's '04 crew cab 4x4 with a 5.3L (tuned on 87 with all torque management removed) is what I would call acceptably adequate towing the same rig. But you have to figure, that thing makes 335ftpnds (happy Angry? ) at 4000 rpm! 400ftpnds is just a number. The 5.3L torque peak is simply too high. If I can get the torque peak to be 350ftpnds below 3000rpm, well yea, that is more than adequate imo.

Basically, I'm looking for cheap torque. Cheap is not doing an engine swap. In the USofA it may be different, but the only vortecs here are $1k and mile'd out. I can get assembled vortec heads for ~$600 shipped, but the vortec heads don't make more torque, just more hp. If you compare the TBI 350, Vortec 350, and Vortec 5.3 you'll see this. Plus all of the time to do the swap and nickle and diming to death. Or, I can spend $100 on a cam, $300 on an intake (intake has to come off to do the cam) and cobble an exhaust together for another couple hundred. And end up with the torque peak I want

have you considered TPI? Yes, the torque peak will be higher, about 3,600, but torque at any given RPM should be improved. L98 w/ full emmisions had 350lb. Entire system from an 80s Camaro or Vette usually runs around 2-3hundred. Just add a better fuel pump in the tank, again cheap, 50 bucks or so. What gearing do you have?

"ftpnds" is something of your own design, you're looking for "ft/lb".

A long tube header into either a good y-pipe or an x-pipe using not overly large pipe would probably be a good start. A better cam as well, sounds like you're working that angle. I don't know how bad the factory TBI intake is; if you're not looking to do a head upgrade, why bother with an intake swap? You could also consider working over the stock heads with a slight cut to the decks to boost compression but then you get into addressing the intake port side and keeping everything sealed up after a cut.

I'd look into one of those air cleaner elements that replaces the filter housing lid; TBI units feed air in odd ways and I'd want it to be available from any direction it wants to pull from. Car Craft worked a 350 TBI truck over a few years ago and they saw some impressive power gains from rather odd items like a device they called "the mixing bowl" if memory serves, a filter adapter that tries to feed air through the top of the TBI unit better than without. Something like 15hp to find with the silly thing.

Small tube headers, 2 1/4" - 3" Y pipe into a good free flowing muffler. I like dynomax super turbos for quiet applications. I built a 2 into 1 Y pipe similar to that for my last 355 race motor, and it worked really well. As much lift as is reasonably possible, and short duration in the 210 at .050" area. Compensate for low compression with timing. That's what I would do.

Ok. You've got to stop with this ftpnds business, it's hurting my head. It's ft·lb.

pres589 wrote: "ftpnds" is something of your own design, you're looking for "ft/lb". A long tube header into either a good y-pipe or an x-pipe using not overly large pipe would probably be a good start. A better cam as well, sounds like you're working that angle. I don't know how bad the factory TBI intake is; if you're not looking to do a head upgrade, why bother with an intake swap? You could also consider working over the stock heads with a slight cut to the decks to boost compression but then you get into addressing the intake port side and keeping everything sealed up after a cut. I'd look into one of those air cleaner elements that replaces the filter housing lid; TBI units feed air in odd ways and I'd want it to be available from any direction it wants to pull from. Car Craft worked a 350 TBI truck over a few years ago and they saw some impressive power gains from rather odd items like a device they called "the mixing bowl" if memory serves, a filter adapter that tries to feed air through the top of the TBI unit better than without. Something like 15hp to find with the silly thing.

First:

http://en.wikipedia.org/wiki/Foot-pound_%28energy%29

Second, I appreciate all of the responses to the people who actually care about the topic at hand and not the exact correct abbreviations for everything. When did GRM become dsmtuners, nasioc, etc?

The intake is unreasonably bad. If I'm going to go through the effort to remove the intake, I might as well replace it. Yes, it is a tad expensive, but it is supposed to be quite the bottle neck. Also, already found the salad bowl mod. I'll probably do it. As for touching the heads, there really isn't a point, and I'm not going to get crazy with a free truck, it just isn't worth it for me to pull apart a perfectly good motor.

I like your ideas Mike, thanks!

And I always thought it was lb/ft. Let's just call it Newton meters and be done with it.

Cheap torque? How about a turbocharger? Probably a small one that will spool early in the RPM range. Should also make the heads, cam, and intake less of an issue.

Teh mad lb-ft

Zomby woof wrote: And I always thought it was lb/ft. Let's just call it Newton meters and be done with it.

According to textbooks, yeah, that's the correct way. It's still pronounced "foot-pounds" but it's really pounds per foot of moment.

I vote we move to slugs/yd. Otherwise known as "yard-slugs."

No, it's not. A lb in this case is a force. A force applied to a displacement (the ft) gives you your torque (work) when you multiply them.

Hence, ftlb and Nm (newton metre).

Did you not even read the wikipedia article I linked, it lays it out real nice and easy:

It is the energy transferred on applying a force of one pound-force (lbf) through a displacement of one foot.

No division, no "x per y", no nothing.

HiTempguy wrote: First: http://en.wikipedia.org/wiki/Foot-pound_%28energy%29

HTG:

I'm not contributing to the lb/ft argument. I find it kind of silly, so I am on your side.

But that link is a complete riot.

In defending your name/ title/ spelling you posted a link to a Wiki "Bad Title"!

+1 for ironic awesomeness!!

Carry on...

unevolved wrote:

Zomby woof wrote: And I always thought it was lb/ft. Let's just call it Newton meters and be done with it.

According to textbooks, yeah, that's the correct way. It's still pronounced "foot-pounds" but it's really pounds per foot of moment. I vote we move to slugs/yd. Otherwise known as "yard-slugs."

Haha. You're an ME aren't you?

MG Bryan wrote: Haha. You're an ME aren't you?

I sure hope not..

As for my link SVreX, maybe I did that on purpose? Naw, I wish I was that clever I did actually go and find the wiki page, but considering no one was bothering to read it, I didn't find a need to replace the link. You win a internet cookie for calling my bluff