TIM Z

iTrader: (12)

Thank ALL you guys for the help and suggestions.^^^^^^^

Man i have a LOT to think about !!!!


Got a Pm from PAT G and he suggested obviously a larger exhaust duration in addition to ported heads and said that would get me where i want to be or close to it. Said i needed more airflow .

So Now, do i change the cam, or add meth and boost??????

Im thinking after talking with Pat(03sierraslt) that i should prob do the cam, then it will be a better support /addition to the meth and 2-3 #'s of boost i want to add.

Im not trying to be greedy, i just want a very low 12 sec/ high 11 sec street truck, is this too much to ask???

Hell i' thought i'd almost be there with my current mods but guess not

Mangled03gmc

iTrader: (95)

Meth and boost If that doesn't work for you, then do the cam. I have often wondered if I would actually see a gain if I went to a boost specific cam. I too like the chop. Duration will will make it chop some, but so will the lsa.. I have yet to see any numbers or times, on diff cams used with boost..

AKlowriderZ71

iTrader: (22)

My 60 ft's aren't much better at 1.77, but 7.82 @ 88.39 mph in the 1/8th, comparing to your 8.2 @ 84 mph, I don't think that's the converter. I think that your current cam is hurting you, you need more torque. Your mph in the 1/4 shows you have good hp, but you need tq to get that heavy truck moving. I think you should change the cam. Something near a 22x/23x with around 8-12 degrees split, and lift in the high .58x range, LSA 115-116.

I'm curious to see what you do, and what results you get. Lots of good ideas floating around in here, but my opinion is that you need to focus on something to increase your torque, and the right cam should do that.

TX Tahoe Z71

iTrader: (28)

My GT2-3 added some serious top end, 3000 rpm and on. I need to put it on the rollers again for some after cam numbers, but the day before I did the swap, it put down 402/455 in 108* weather. My butt dyno says in picked up 40-50rwhp. Results to come...

TIM Z

iTrader: (12)

Yeah John , i love having chop, the sound of a powerful engine is one reason i love my truck. What Cam do you run currently?

Meth and boost will come reguardless!!!
Again thanks for the post Roger, This is exactley the stuff i wanted to come out of this thread. Im still learning myself.

You said the MPH indicates i have the horsepower to get it done, but need more TQ to get the ET lower and get moving. I like this theory.

I do have a free restall on the verter, but am not going or wanting to tear it back out anytime soon LOL, Im hoping its not my prob, but see lots of blower guys running 2600-2800 verters.

I will def. post what i decide to do.

Sounds good man, the butt dyno is where its at haha! I'd like to see what improvement you get. I wish we had E85 more available here.

Mangled03gmc

iTrader: (95)

I am running a Comp 224 224 581 581 on a 112 lsa.. My heads are just mildly done( infinite angle valve job, some very slight porting.. I think that you would def beni from a bigger converter also.. Thats alot of truck, to get moving.. So better 60's means better 1/4 for the most part.. I am by no means a cam expert, but unless you get another cam on possible a different lobe, I can not see that much hp being had by just a change in the LSA, since the blower is blowing fuel/ air into the cylinders.. I see that all the cam's PAT G spec's are pretty big on both the lift, duration, then you have guys like stock48 running a smaller cam, getting excellent numbers, so is bigger isn't always better.. If the tight lsa is blowing boost out the pipes, turn the boost up

Beatdown Z

iTrader: (18)

Not going to suggest changing them, but what gears does your truck have? just out of curiousity...

skolman91

iTrader: (28)

With all this talk about more air and exhaust duration, dont you have the small ebay headers?? Whats your exhaust setup after the Lt's? Can only get as much in, as you get out..
just a thought..

AKlowriderZ71

iTrader: (22)

Just to prove a point, this is my timeslip is with stock exhaust manifolds & cats, stock 76mm throttle body, and a 5.3 liter with stock heads. Remember, the cam is the "brain" of the engine, valve events are everything. You need torque for that heavy 4x4 extended cab to get it moving. Once it's moving, it moves out well! His converter is already giving him 1.8 60 ft's, and once he learns the best launch, it will likely be in the 1.7's.

skolman91

iTrader: (28)

Yes i see your point, so why did you switch to arh Lt's and exhaust then? To make the blower breath better and upgrade right.. Also you had what i would call a more properly specd blower cam, and little bigger converter when comparing the two.
Now i wasnt suggesting he go out and get some $$ 1 7/8 headers, doesnt really need them to reach his goals he has in mind. Just sorta throwing it out there that he does have 1 1/2"primarys and 2 1/2" collectors combined with the lack of exhaust duration..

I think the problem is maybe slightly the cam and converter(not overwhelming factors), but mostly iat and timing problems.. Got any tracks logs?

Find some e85 tim, i know you guys got some corn over there somewhere..