OK Guys. Here is a good one that has me sooooo frustrated. I have been working on my lo3 91 camaro since Christmas and some of you secretly already know. Here it is. I have bore it .40 over with hyperutectic (sp?) pistons and speed pro light weight race rings. The heads are flowed to 230 cfm and now sport a three angle competition valve job. I got a custom ground comp high energy extreme cam with pretty good specs. (550 lift 224-230 @ 50...custom cut for my motor and specs) 1.6 roller tip rockers top it off. I have a throttle body from Turbo City (590 cfm) and 350 injectors on top of an edelbrock TBI maniflod. I also have all the spacers. this includes TBI and Injector spacers. Tranny now sports a corvette servo, recalibrated valve body, heavy duty clutches and sprags. It also has a b-n-m Torkmaster (yes it is spelled right...tee hee hee) converter. Poly motor and tranny mounts also. Last year I ran (I run in the eighth mile) 9.40's with a 60' of 1.93 ish. After I did all of this I ONLY RUN 10.75 with a 2.6 60'!!!!! WHAT THE HECK IS WRONG??? Would the chip make that much difference? It is still the basicly stock chip (ads thermo). This car was dyno'd (a healthy 384 ft/lbs @4000 363 hp flywheel)and expected to run 8.40's. Also the converter is supposed to stall at 2500 and the tires rip loose at a grand. What should I look at? I have upped fuel pressure and tested timing. Is it all the chip and converter? Please post any thoughts. I am frustrated being under the hood every day for 6 months. Thanks guys.

Eric

 

what would that be in the 1/4

 

My guess is that it is time to sort out that 2.6 60ft time....



Something is amiss here....
You indicated that your running a locker ...

What kind of shape is the rest of the rear suspension ?
Which way do the lca's point ?
(is the frame mount lower than the axle mount)

 

yeah....maybe it's too much power for the suspension

 

Sounds to me you are spinning up the tires pretty bad. Like its all been said before, power is nothing if it ain't getting to the pavement. If you're pushing that kind of torque it's time to change the torque arm, lca's panhard rod and even springs and perhaps look into sfc's as the stock ones can barely handle a 350's output.

 

Find yourself a good set of drag slicks my good man, attach them to good gears and a nice posi and find those times you've been looking for. A new set of LCAs would also go a long way.

 

It won't ever run right on a stock chip.

 

It does not spin the tires. I say it rips loose at a grand I don't mean when I mash the gas. I mean when I try to power block it. I hit the throttle and the car is like...you want me to do what?????? It just kinda sits here. That is why I figure it is the chip or converter. I also thought that the throttle body was 400 CFM and turbocity said it was 590. I upped the fuel pressure all the way up but I have not run it yet. The track does not open til SAT. By the way Chuck! it is a locker with great tires. I don't need a posi.

 

So let's get the details clear... you floor it and does nothing?

 

If you're cutting a 2.6 60' then you're spinning to all hell or you have a major problem from 0 - 40 MPH. With 350+ HP you should be just 1.7 or 1.8 60', once you get some traction then you'll find the times you're looking for.

 

Well, I hit the throttle and it has a HUGE hesitation. Also the mph's, which are an easy way to tell horses, are down BIG TIME. Last year I was getting 71.8 MPH in the eighth. Now only 69-70. Not getting the horses. So what I realy want to know is will not changing the stock chip cause my car to have the hesitation and loss of power after a 200+hp buildup? Any chip guys out there that can tell me?

Eric

 

I was driving a 383 450/500 ft-lb 91 GTA with 4.10s and street tires cutting 1.9xx 60 foots ON A STOCK rear suspension..

I think the dood just needs to learn how to drive the combo.

Kat

 

Because you were describing a hesitation, I would definantly double check your timing and fuel pressure, also you may want to start looking into getting a custom chip.

 

its in the tuning. play with the fuel pressure but you need a custom chip

 

The Edelbrock TBI intake is WAY too small for those heads and cam.

It's choking the engine off big time. Get a nice Performer RPM or Weiand Stealth and use a TBI adapter plate on it.

I just read that you don't have a custom chip. All I can say is I want to bake you a damn cake because I never thought in a million years that the car would even IDLE with that kinda cam.

 

Well, if no one else will state the obvious... I will. YOU NEED A CARB!!! No chip BS to deal with, no pooling fuel in the intake, no choking the engine... Get a 750 and be done with it.

 

Hmmm...
You would probably find the "carb board" more in
keeping with your expertise...

 

I don't think he would get anywhere putting a 750 on it because he would only need a 600cfm at most because it's still the 305. A 750 would be too much carb and if he bolted it on, he wouldnt get anywhere.

 

Wouldnt that come to a total of .580 inch of lift with the 1.6 ratio rockers??? ummm, thats really big. would you really need that much lift? Im hoping it was a mistype.

 

Ahahahahah who let all these comedians on the board! hahahahahah im dying


First off the car will NEVER EVER EVER RUN ANYWHERE NEAR RIGHT OR FAST WITH THE STOCK CHIP

YES THE CAR CAN AND WILL GET SLOWER with mods and the stock chip. Especially cammed like yours is.. .forget about suspension and all that jive its the chip.. been there done that it wont run right and right now you are way behind the curve as far as chip burning goes you should have learned about it before you did all this stuff the best advice i can give you is get a carburetor , like a double pumper, and a single plane


lets assume you keep going on the path you are going and do manage to get the chip tuned for it, youll need to change that intake manifold that is a terrible choice for the rest of those components

 

Hmmm...
Sooo...
You are suggesting either a milder cam combination
or a carb/manifold swap...

In your estimation what would you consider an upper
bound for a cam based on a stock prom and his
current intake combination.

 

ok guys. I have heard a lot of crap. so here it is. I am keping the throttle body, I am getting a custom burned prom, YES THE CAM SPECS ARE RIGHT, It pulled fine on the bench dyno, it is not spinning off the line, and yes the guy DOES know how to drive it. I wish I would not have posted. Every post here that I have ever done has turned into something like tis so I believe this may be my last post. I did not ask everyone if I made bad choioces, I simply asked if anyone else had this problem before a chip change.

Eric

 

Well at least run it after you get a custom chip and let us know how it turned out in the 1/8

 

The stock chip is basically dumb after heads, cam and intake changes. This is why Edelbrock themselves will supply you with a custom chip for free if you get a complete kit from them. They know full well the stock chip has no idea how to deal with massive amounts of air. Thus it automatically goes into limp mode when values are out of range. For those users who haven't had a complete sensor failure, the GM stock chip is designed that when confused or has input that is off the scale or out of range, it will go into limp mode which dumps the maximum amount of fuel it needs to run causing a super rich condition and almost no power basically enough to "limp" the car to a mechanic.

 

Yes you did ...
But try to take it in stride... What you are doing is
worthwhile and many will benefit from it.

The good thing about lists like this is it keeps me out of jail
Normally if I had the physical proximity and a few drinks...

At any rate I would be interested in your progress...
Just pour yourself a drink... and ignore the dick heads...