96-99 454 Vortec owners?

[skills4lou]

There's supposed to be a dyno shop opening up just north of me this summer. When they do I'm gonna get a baseline run in, then start playing more.
I definitely like my BBC towing. My 94 Sub 350/4L60E was OK, but definitely felt underpowered at higher altitudes. When I was in WY (6200') it was working just pulling my little two horse trailer. My current truck doesn't even really know it's there. Of course, the Sub got 19 around town, and 22-23 on the highway, so it's a trade off. Oh well, I don't put enough miles on to have that huge of a fuel bill. I've only put 10K on in over two years. And that's including one trip across the US!

[justin302]

Any other 7.4 owner try the smaller gap trick?? Did ya notice anything??? Here is one thing that helped out my idle and slight power increase. That is a 4" intake elbo with an adapter down to 3.5" to the mass airflow. I used the stock air box, so I can suck in cold air.[IMG][/IMG]

[N0DIH]

I just eliminated all the bends.... I went with a Ferco coupler and directly connected the TB to the MAF to the K&N and got rid of everything else. Mine isn't sucking in cold, gotta fix that soon, but still runs better....

Originally Posted by justin302

Any other 7.4 owner try the smaller gap trick?? Did ya notice anything??? Here is one thing that helped out my idle and slight power increase. That is a 4" intake elbo with an adapter down to 3.5" to the mass airflow. I used the stock air box, so I can suck in cold air.[IMG][/IMG]

http://www.fullsizechevy.com/forums/...post&p=2999976
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Mine is close to this but on the L29/454, mine has NO PCV though.

http://www.fullsizechevy.com/forums/...ec-trucks.html

[bankspowered98]

From the sound of it I really need to get ahold of Jesse. The ol dog is due for some more power.

[N0DIH]

If you can convince him to disable TM, you can probably smoke the tires off it, else, probably lucky to spin them on wet pavement without really trying hard!

[bankspowered98]

Alright then, its sounds as though I have some convincing to do. haha. Thats what I want, so I will try my best

[N0DIH]

I am not sure how much it will reduce trans life, so be warned, and I am sure he will....

[bankspowered98]

I have ran nothing but synthetic fluid through the tranny for the last 35000 miles. So hopefully that will help me out too.

[WideOpen]

Originally Posted by bankspowered98

I have ran nothing but synthetic fluid through the tranny for the last 35000 miles. So hopefully that will help me out too.

Did you notice any improvements in trans performance when you changed to synthetic?

[bankspowered98]

It felt smoother and the trans temp dropped around 15-20 degrees. I also got on average about 20 more miles per tank. My worry was since the trans had always had just regular fluid in it if everything would hold up and it did very very well. I have changed it once since then and comes out looking just like it does when it goes in. I bought the truck with 76000 miles on it and now have 129000, (turned that yesterday) and not an issue yet. knock on wood.

On a different not, I ordered my whipple charger today. It should be here either wednesday or thursday so I will keep this updated with the install.

[N0DIH]

I just got my FPR changed on mine (that is a pain to do.....) so if mpg responds well, I might just go synthetic in the trans. I hope to do all efforts now to improve mpg.... After 20K miles of 10 mpg, I am game for better!

[WideOpen]

Originally Posted by bankspowered98

It felt smoother and the trans temp dropped around 15-20 degrees. I also got on average about 20 more miles per tank. My worry was since the trans had always had just regular fluid in it if everything would hold up and it did very very well. I have changed it once since then and comes out looking just like it does when it goes in. I bought the truck with 76000 miles on it and now have 129000, (turned that yesterday) and not an issue yet. knock on wood.

On a different not, I ordered my whipple charger today. It should be here either wednesday or thursday so I will keep this updated with the install.

Where did you find a whipple charger at? I thought they quit making them. One of those would be real nice for towing.

[bankspowered98]

actually ran acrossed it on a web site called www.racingjunk.com I am on there quit a bit with all the racing we do throughout the states so a gentleman had one that I managed to pick up. It should be here by thursday. I also ordered a snow water/methanol injection kit and it should be here friday.

[jp1584]

i have a 2000 crewcab 2 wheel 454 with 46,000 miles on it. love the truck but it has the warm start issues. i hope somebody can help me out with this.i average around 14mpg,my truck is completly stock. i hope to upgrade the tires soon.right know im running wimpy 245/75/16. do you guys know of a good tire size that will not rub this truck. it sits up pretty good for 2 wheel drive

[N0DIH]

Cold start good? Honestly just solved my issue. Fuel Pressure Regulator. $46 @ Autozone, $77 @ NAPA, same IDENTICAL part, even PN on part itself is identical! I have been trying to troubleshoot this for a long time, I don't replace parts for nothing, (nothing ticks me off more than to replace a good part with a good part and waste $$$ on it, you can pay car repair shops all day long to do that for you, they do it all the time), and nothing could pin down 100% that this was it, but this was the LAST thing I could come up with.

I did a vacuum test, old and new were identical (even up to 25 inches, both held vacuum perfectly). Bleeddown of both once engine is shut off, same. But the new one is 10 psi less pressure. And the truck runs SOOOOO MUCH BETTER!!! The intake plenum was all wet with fuel. But fuel pressure test from FSM passed fine.

Only way I could confirm it was bad is the fuel that dripped out of the vacuum line when I pulled it off.

I would look into it if yours is stock.... My mpg has been 10 for the last 1.5 years over this stupid thing!

Toss in a cap/rotor if yours is old while you are in there. Or me, just polish up the old one..... Cleans up nice.

Starts warm like a DREAM! Nice and day difference....

My ride is a 99 K2500 Burb, I put on 265 75 16's, love the look. GM states NO tire chains with 265 75 16's, rumors are 285 75 16's fit, but that is the upper size limit. I have NO complaints of the larger tires, other than a little more stretch to get in the door... But it looks fantastic over the 245's..

Originally Posted by jp1584

i have a 2000 crewcab 2 wheel 454 with 46,000 miles on it. love the truck but it has the warm start issues. i hope somebody can help me out with this.i average around 14mpg,my truck is completly stock. i hope to upgrade the tires soon.right know im running wimpy 245/75/16. do you guys know of a good tire size that will not rub this truck. it sits up pretty good for 2 wheel drive

[jp1584]

thinks for the help, yeah i was kinda thinking it was the fuel regulator. i heard it is a pain to get to , not for sure if im going to try and do it.did changing the regulator out improve your mpg and did you notice a decrease with the bigger tires

[N0DIH]

Well towing I still got 9-10 mpg.... Heavy...

But with the tires, nothing stood out, 10 was still 10... Now with the FPR, I am anxious to find out, only driven it 50 miles or so now, so I really don't know yet, but I would expect it to run better, it feels so much better, exhaust smells better, it doesn't have that "laboring" feel now...

[jp1584]

let me know how that new fpr works out for you on the mpg,do i have to take off a lot parts to get to it

[bankspowered98]

I had the exact same problem a while back FP regulator solves it, good call NODIH. As far as tires, my k2500 4x4 has 305/70-16 Pro-Comp Xterrains on it now for the winter and I have no rubbing issue what so ever. It definately fills the fender wells but otherwise its good to go. If you dont want such a wide tire go with a 285/75-16. Same tires, just a shade bit more narrow. Check out my gallery if you want to see the clearence. GOOD LUCK

[WideOpen]

Originally Posted by jp1584

i have a 2000 crewcab 2 wheel 454 with 46,000 miles on it. love the truck but it has the warm start issues. i hope somebody can help me out with this.i average around 14mpg,my truck is completly stock. i hope to upgrade the tires soon.right know im running wimpy 245/75/16. do you guys know of a good tire size that will not rub this truck. it sits up pretty good for 2 wheel drive

I put 285/65R18 BFG all terrains on mine and had to trim a little off the plastic front air dam, no big deal. I didn't notice any drop in mpg. I think lowering the engine rpms while cruising makes up for the additional size and weight of the tires. My truck has 4.11 gears also. Just make sure to recalibrate the speedo. This tire size might be to big for a 2wd.