Need Some Help Tuning The Truck

[RSWORDS]

Ok after only doing right at 300HP with my 89 its obvious I need some tuning. Right now I'm running the 6x16's 15psi of fuel pressure from a Walbro 392 (it does not pull down at all under WOT) 62/74/14 turbo and all the other basics like pins and what not. I really want to join the 500HP club running an automatic. I think that will be a 1st, correct?

First before you even say it Bill the intercooler is going in in the next week or so hopefully. Just trying to get all teh bugs worked out. Bill you have said you bet I'm leaving almost 100hp on the table from being non-ICed. That will bring me to 375-400HP if you are right.

AFC
Been alot of talk about tuning the AFC. What all are we tuning? I know my truck is fueling WAY hard down low... I mean REAL hard. Like putting the fire out hard. I have come up all the way on the star wheel and it helped a little bit.

Timing
Still runing only a 1/8" bump on teh 6x16's, BC went two teeth and stock mark, Others have gone 1 tooth and a little towards the head. I have to take the front off the truck for my intercooler so I might as well jump some teeth while its easy to get too. There are some old posts about shaving the advace piston. Dont see alot of talk about it lately. Have we giving up on this? I like the idea of more advance and overall timing because it wont hurt the spool up as much.

Turbo
I'm running the 62/74/14 S300. I know that fast spool up is the ticket for High HP 1st gens. And I know that twins are the way to go for high HP. Problem with that is I pull the truck And can only run a 2.5 (64mm) turbo in my class. Should I step up to the 64? How much spool up will I lose? I'm worried that the extra timing is gonna hurt my spool up but at the same time shouldn't getting the AFC tuned well help it?

What else? I hear people metion teh VE "book" or "bible" often. What book do you all have and were can I get it? I feel I have a set-up worth ALOT more then its giving me. I think its all in teh tuning now. Just need to get that tweaked. Thanks in advance for the advice.

[RSWORDS]

Oh and if it helps here is the video of the dyno run on Daves dyno. 1st run was fuel only. Last two were with nitrous.
http://www.youtube.com/watch?v=M6XPr6Oy-4U

And here is the graph. Is it me or does it look like Mike started teh pull way high in teh RPM's. Could that hurt my numbers on paper because we make all the power down low? These are corrected numbers.

[dpuckett]

What kind of convertor do you have? Stock or aftermarket? Count on a stock convertor robbing 30-40% of available power, i.e. if you make 500hp at the engine, you will only get 300-350 to the wheels with the stock convertor.

I'm thinking the 62/74 may be hurting your bottom end spool. From what I've read, they are more for higher RPM P-pumped outfits. Might step down to a 62/65? Anyone else have a rebuttal?

AFC- what kind of pin are you running? Have you tried a governor assembly from a later pump? Talking to Terry Blue, he said they changed the governor when they went intercooled- cut bottom end fuel to meet EPA regs.

Good luck getting it figured out. Not sure how much help I was.......

Daniel

[Tacoclaw]

What kind of convertor do you have? Stock or aftermarket? Count on a stock convertor robbing 30-40% of available power, i.e. if you make 500hp at the engine, you will only get 300-350 to the wheels with the stock convertor.

I'm thinking the 62/74 may be hurting your bottom end spool. From what I've read, they are more for higher RPM P-pumped outfits. Might step down to a 62/65? Anyone else have a rebuttal?

AFC- what kind of pin are you running? Have you tried a governor assembly from a later pump? Talking to Terry Blue, he said they changed the governor when they went intercooled- cut bottom end fuel to meet EPA regs.

Good luck getting it figured out. Not sure how much help I was.......

Daniel

*Points to R's sig.*

[crewcabxlt]

i think you on the right track, ive found the afc cone profile affects spool-up alot when running big injectors. i run a stock ground pin with a slightly ground afc lever, however I USUALLY RUN ON THE SHOLLOWER STOCK PROFILE. truck performs better. i like a turbo that lights quik to take advantage of low end fueling of ve. try a stck afc cone.

[peobryant]

Do you plan on running nitrous still? If so, timing should stay close to stock.

I think the best turbo would be a 62/71/14. Should be able to light it fairly quick, and Josh Ayers made 501rwhp with one of these.

[RSWORDS]

Yeah aftermarket Convertor, Might spray a little but I want the 500 on fuel only first. Its a pulling truck so i cant spray at the pulls. I like my 62/74 becasue of how free it flows up top. Things gets toasty as is up there I bet they would be real nasty with a 62/65.

In my reading it looks like inlet pressure to the pump has alot to do with the timing advance too. While I run a steady 15psi and it does not fall off should I hook up my boost reference on teh regulator to bring it up with boost?

[RSWORDS]

So i've dug throgh alot of info on teh advance piston. Not seeing alot from guys that that have done it though.

Looking for a little advice Bill and Brian...

[bgilbert]

Sorry Bobby, I don't believe in the non-lockup tranny in our trucks. IMO, even if you had the best 727 money could buy, to put down 500rwhp you'd probly have to be making 650hp. We know that's probly not ever gonna happen.

Maybe oldcool90 will remind me exactly what he gained going from nonIC'd 727 to IC'd 727.... Matt?? Seems like a gain of 60hp. Then without any other changes he gained around 100hp going from IC'd 727 to getrag, IIRC. Matt?

IMO it's hard enough to put down 500rwhp in a VE truck, and to do it, it's gonna take a manual tranny. Oh and we're talking fuel only, non-west coast bs HP numbers lol.

As far as turbo, I think you've got a good one, leave it alone.

And yes, hook up the boost referenced fuel pressure. Try to set it at 1/2 to 1. You don't want big fuel pressure when you're only pushing 20psi of boost... or less.

[RSWORDS]

cool bill. Yeah I have kicked the idea around of swaping a getrag but I like to go fast. I guess i'll find out how far the 727 will take me. I dont nessesarrly want to stick with it but I dont have any money for a swap right now. The tranny was built by a guy (minus teh convertor) who builds all his own trannys for his 9 sec drag truck. He used all the same parts as in his trannys and set it up the same. It should be the best you can do with a 727. Its pretty tight but still no lock-up. I figured it has to pass more then stock, but I know it still eats up alot.

Whats your thoughts on AFC tuning? Also on timing, Specifically triming 2mm off teh retard side of the Advance piston.

[bgilbert]

Is this 9 second drag truck a gasser? If yes, there ya go.

I haven't done anything to the timing piston.

AFC, what have you done to the afc lever? With a single turbo, I made more power the more I ground off the lever and fuel cone. With the twins, it's been the opposite.

[RSWORDS]

Good point, just saying its the best it can be... Still not great but the best it can be... Kinda like me...

The Foot is stock. I've been reluctent to grind it because everyone talks about needeing it for high HP.

[SChandler]

If you want to stay with an automatic, then I think your best bet is a 47rh with a stand alone controller for the lock-up converter. That should bring up the horsepower (and cost). Plus, with the overdrive gear, you could swap axle gears for something a little lower than 3.07 to help with the sled pulling and still be driveable on the freeway.

[peobryant]

If you want to stay with an automatic, then I think your best bet is a 47rh with a stand alone controller for the lock-up converter. That should bring up the horsepower (and cost). Plus, with the overdrive gear, you could swap axle gears for something a little lower than 3.07 to help with the sled pulling and still be driveable on the freeway.

I do agree with the 47rh being the best choice if he wants to stay with an automatic, but if it's a 47rh, he won't need a standalone controller. If it was a 47re he would need a controller. Just a couple switches for the 47rh, and he'd be good to go.

[SChandler]

If you want to stay with an automatic, then I think your best bet is a 47rh with a stand alone controller for the lock-up converter. That should bring up the horsepower (and cost). Plus, with the overdrive gear, you could swap axle gears for something a little lower than 3.07 to help with the sled pulling and still be driveable on the freeway.

I do agree with the 47rh being the best choice if he wants to stay with an automatic, but if it's a 47rh, he won't need a standalone controller. If it was a 47re he would need a controller. Just a couple switches for the 47rh, and he'd be good to go.

By stand alone controller, I meant controls for the lock-up. Thanks for clarifying what I was thinking.