My Z28 has the factory L98 350 which is said to run around a stock 14.8. On the racetrack, my car will run 1.8 - 1.9 60ft times, with a 1/4 time of around 14.7. My car has several, several performance modifications to it, but yet I'm running identical to stock 1/4 times. What is the problem, here is a list of all my mods. I've heard that my computer is not nearly adapt to my entire setup, but it wouldn't hinder me from running low 14's like I should, right? It's actually quite saddening, someone sees this list and asks if I've broke the 13's yet, but all I can say is I'm running a stock 1/4 time practically. What do you think my problem is? I just absolutely do not understand it... (list of mods)

Holley Stealth Ram Intake
BBK Twin 52mm Throttle Body
Edelbrock Water Pump
MSD 6A Spark Amplifier
MSD Billet Distributor
MSD 8.5mm Plug Wires
Bosch Platinum +4 Plugs
160 Deg. Thermostat
Flowtech Headers
B&M 2400rpm Stall Lockup Converter
Hughes Performance Street/Strip 700r4 with Tranny Cooler
Crane Cams Roller-Rocker Arms
K&N Air Filters
3:23 Rear Gears
Custom Ram Air
Aftermarket Dual Radiator Fans with Manual Switch
Edelbrock Torque Arm Bar
Eaton Limited Slip Differential
Flowmaster Delta 40 Muffler
Hotchkis Strut Tower Brace
Hotchkis Subframe Connectors
Hotchkis Rear Control Arms
Hotchkis Adjustable Panhard Bar

 

how many miles on your engine?

 

I got it with around 100k, now it's around 102k.

 

i know your pain. run a compression check

 

I think you problem is tuning. You can check out your motor with a compression check, but I think it will come down to tuning. You can't bolt an intake like the Holley on to your car and expect big gains while still running the stock tune. Your computer has no idea whats going on. And add the fact that your car is a SD setup, which doesnt adapt to change the way a MAF car would, is all the more reason is get a tune!!

Try pcmforless, they tuned my 383 and I have no complaints!

 

Stock heads? That will definately choke up your intake/cam combo.

 

Yes stock heads. Heads/Cam are in the works, but what's the point of that if I'm not running like I should...

As for the compression check, how would I go about that? A shop? A special 'tool'? I have no idea how to go about that. And with PCMPerformance, how do I go about that, do I just tell'em what kinda car, what my mods are, what I want to do, etc.? Do you really think the computer is the key problem. There's also something funky with the transmissions, it's like a semi-manual valve body, it won't shift up on it's own unless if in Drive/OD... at the track, if I put car in Drive and race, I pulled 15.9's twice. To get into the 14's, I have to manually shift the car the whole way... dunno if it's terrible that my car sucks in Drive, but I don't think that's right. Give me advice on how I go about this stuff though, what will a compression check tell me? How much does a compression check run? How bout a new computer?

 

That sucks that Your times suck! You got all those mods and Your car aint doin ****!!! Something has definitely gotta be outta tune!

 

Yeah, way to go Isaac Newton, we've gathered that. Your input certainly isn't helping.


But honestly man, I think that if you did the heads and a PCM tune youd see massive gains. Also, give us YOUR 60' times and your MPH in the 1/4 mile so we can analyze where you are going wrong. If you are running a 2.5+ 60', then we've found your problem.

 

It's the stock heads they are killing your power I have the same problem right now I got a set of AFR heads that i havent put on yet they should fix my problem.

 

Stocks heads and cam are made for low rev power. The HSR is made for high rev power. And you shift points are set for a TPI powered car, not a HSR powered car.

I think you already know the answer to your problem. Get heads and cam to feed HSR at 6000 rpms, then move shift points to that rpm.

Then say hello to 13's

 

I say both the better (port matched) heads and the tune. PROM work is a necessity when you add intake/exhaust upgrades. But if your gonna do your heads, wait to do the tune until then. That is unless you tune yourself. You might be too lean/rich? I plan on data logging when I put on my new headers. My compression stinks as well. 130k on the clock. I burn 1 quart of oil between changes. I feel your pain! Check out my vbgarage. I'm still in the mid 14's as well.

 

I run 1.9 60ft's at around 94 - 95mph. I have plenty of low-end power, but not getting much on the high end. Through the 1/8, I'm runnin with or slightly beating LT1's, but after that... I got nothing.

So a new computer will run me around $125 + correct? As for heads, how much will a setup run? I've reseached cams, so that's no problem, but I haven't looked into heads that much... heard they can cost a pretty penny.

 

A well maintained stock SD L98 should net u mid 14's or better.

U either have something wrong that your missing or its could just be worn out.

Either way to take advantage of what u have already, go thru things 100% and check everything out electrically and mechanically.

Then begin reading the stickies on the DIY PROM board a few times. Then start asking questions and getting the stuff needed to do your own tuning.

I have a feeling u will find more power there.

later
Jeremy

 

Yeah, you are flowing more than your heads can handle. Once you start getting into that high RPM range, you've got nothing. That's the same kiind of number I have with my 1/4 mile slips, except I am running a 2.1 60', but getting a 14.5 at 94mph.

I mean, you are supplying the air for high RPM (HSR), you are giving your engine the ability to use alot of fuel and air together (cam), but you are just bottlenecked by your heads which are making the process of air/fuel intake, combustion, and exhaust flow rediculously slow. Everything else, besides a tune and shift points, is in order. I mean, your ignition is great, that will more than keep up with the power you want. Seriously, look into a set of good heads.

I suggest something aluminum with 180cc-195cc intake runners.
If you are strapped for cash, keep an eye on Brodix IK180 heads which retail for $1039.99, or Trickflow's Kenny Duttweiler Signature 23* Aluminum cylinder heads, which retail for just about the same. The Brodix heads flow slightly better all around, however, and are what I am ordering in a week.

 

Could keeping the stock heads but putting in an aftermarket cam be worth it... or do I really need the heads? It's just hard for me to round up $1000 to do heads.

Back to this computer thing, from PCMPerformance, it's showing it'll cost around $125, if you think that'll make a significant difference, I'll order that in a week or two. It says it's only like $50 for an update(for when I do heads and such I suppose?).

Again, the compression check... who could do that for me and how much?

As for the shift points, like I said in a previous post, I have to manually shift the car... if I put car in Drive, it's useless when racing.

 

Crap, I saw "crane cam" in your list, but you were just referring to the rocker arms. Yeah basically this is going to be a problem too. Getting an aftermarket cam with just your stock heads and springs isn't going to work to well, as your springs will not be able to handle anything more than just a mild cam.

I suggest this:

Pick yourself up a roller cam for about 250. Comp makes some good choices. Im going with a 270HR which has a .495/.503 lift.

I would suggest vortecs, but that would mean you need a new lower manifold to fit the heads, so that is out of the question. You can pick up a set of stock replacements or some Dart Iron heads and maybe do some porting as well, as there is potential to up to 20hp there alone (and with your combo you have already, I wouldnt doubt it for a second). All in all, you will be looking at about 800$-1100$ with the cam if you go that route.

Another thing you can do is have your stock heads machined for bigger springs, and just get new springs. Give them to a machine shop and let them have at it, and for a few hundred, you will have a set of decently flowing heads that will support your cam. If you are on a budget, this is the route I would go. There is potential in those TPI heads, believe it or not.

It sucks, I know, but it's something you can't cut corners with. Sure, a chip may pick you up about 20hp, but you will still not even be close to where you want to be. Start saving now my friend.

 

So do I have to pull the engine to do the heads or can I pull'em out without having to tinker with to much other stuff. Theres an O'Reilley's machine shop in town, could they do that stuff, or would it be best to find someone else to go? Any idea how long this would take and how much it would cost? I am definately on a budget(my car was up for sale because I couldn't afford it, so yeah, no much spending money), I'd love to pick up some fancy new heads but it'll be a few dozens years before I could afford it(haha).

 

ive got a mainly stock 88 l98 with headers hallow cat and a filter and she runs 14.1 14.2 depending on temperature u might need a new chip burned for ur mods and then see from there but it should be close to 13's with them mods also a set of gears would be good

 

You should look on ebay and in the classifieds for some good heads the stock heads ported wont support a 500 lift cam. My stock heads are fully ported and I have a ACCEL Super Ram with a .503/.510 lift comp cam and I only have 250 RWHP the heads are killing my power. So if I were you I would look for some good used heads.

 

See... everyone I know with slightly modded L98's run low 14's... and I have a huge list of mods and I'm running 14.7. I have a buddy with just drag radials and 4:10's and he runs 14.2's. That's what is confusing me, I figured I should stomp everyone with this stuff... I didn't think all these mods would actually hurt my performance(well technically, not going faster).

 

Honestly if your not willing to get into chip work(yourself) I'd check the reliablity of the engine(compression/leakdown test) make sure your getting good spark, the works.

Then put you heads and cam on, and then pay for a good dyno tune. It will be expensive, but without a tune your screwed and it'd be better to get a quality tune that some mailorder one. Alot better.

 

Does anyone think that maybe the nasty summer of Missouri could play a big factor in his slower-than-should-be times? What I am saying is, I never run my cars at the track in the summer. It's hot, and a waste of time, money, and gas. You got to be at least around 100* there, and humidity has got to be worse than here in AZ. We are seeing 34* humidity this week and it's a hellish 110*.

I think the heads are restrictive and so is the cam, but those aren't the big issues, IMHO. I think it's the weather and a stock SD tune. If you were running a MAF car you would be doing much better.

But again, don't expect the best times during the next few months.

Hope that helps.

 

dont take this the wrong way, im not trying to insulte you or anything, but it could be driver related. what were you running before? and if its practically the same, then do a full tune (should anyway).

 

hes got a good 60' foot time and with an automatic i doubt theres anyway to screw up anymore with an automatic. THough i left my car in D and ran a 13.9 with a 60' time of 1.9...mods are in my sig.

I think its gotta be ur tune though i really cant understand how it would hurt ur runs still id think u should easily be low low 14s...i ran my car in cold weather(40s) with a fresh tune up every fluid new all of it. This is after i got my car...i have not run it since my suspension and new wheels.

Ive always been told with a stock L98 car to just leave it in D and let the tranny do the work, its shift points are where they should be.

 

hey for now get a custom burned chip and see how much better the car performs, cause w/o a custom chip your sd doesnt know about the mods thus hurting your performance.

 

Like I said, with my aftermarket 700r4(Hughes Performance), the shift points or something is all jacked up, with car in Drive... the car itself will run a 15.99(did it twice). To run a 14.7, I have to manually shift the car(14.6 my fastest, 14.8 the slowest). As for the racing conditions, I made these runs in April in 50 - 60degree weather.

Should I get a PCMPerformance computer THEN a Dynotune... or is a Dynotune pretty much the same as buying a new computer?

 

I think you are getting a bit confused here. It is not a new computer you need, just the chip that stores the spark and fuel tables, ect.

Not sure what a dyno tune entails, but if you have the money and want to go that route, I think thatd be your best bet. I think they alter your computer a bit on the spot, but the benefit over just getting a chip burned is that they can find out exactly how much power you are making with the changes they make. At least this is what I am lead to believe.

 

since a stock can run as low as a 14.4 you should definatly be in the 13's. Id take it to a tranny shop and maybe see if your cables from the tranny to TB are adjusted correctly or have them figure out why it wont shift right in D. Sounds like you got nice 60' times so maybe your tranny just aint working right after 1st gear? Definatly get a chip burnt, if you dont have the money then sell somthing because its a must and they are only like 150 bucks or less.

 

So having a chip burnt means just buying one from like PCMPerformance... right(sorry newb here on this)? If so and if you guys think it's a serious problem, I can afford ordering one as soon as Friday. Then two weeks from that, I can take the car to a local town have it dyno'd... where they can make even more adjustments, correct?

 

If he buys a set of the AFR's/Brokix/Trickflow 23's, how much will that raise his compression over the stock heads? Are our PROM's sophisticated enough to change the L98 tune with just a compression change or is it more of being able to adjust for the better head flo rates? (I'm really naive on PROMs)


I've got some of the same 'slow' issues with mine (1988 IROC L98 700R4 9-bolt 2.77)

I feel like I'm driving an old chevy cavalair. My question is if this PROM company that's been mentioned is top notch? And how much should the 'average' head replacement job cost?

SPEED 88- you mentioned that they tuned your 383? What all info did you know to provide them? Was the new chip significantly better?

Insane IROC & Guitar Junki 17- between the 3 heads you mentioned; do all three of these heads pretty much make power over the same rpm range? and did either of you consider having a machine shop massage a set of the old corvette 113's???? I want a really wide power band as I live near the coast and deal with really winding roads. My compression is great, burns no oil but totally runs out of power by 4000rpm and it will barely chirp the rear tyres with the 2.77 posi.

Cam-aro- Would you be able to afford a set of slightly used ones that periodically show up on this board's Classifieds? The ones listed sure seem a chunk cheaper than new units.
Nitro

 

Each manufacturer makes heads with different sized combustion chambers, so you have a choice. If your stock chamber is 64cc, then you will find a head from either of those companies with that matching cc. If you have 58cc in there now, you should be able to find a head with that same combustion chamber. I know that the IK200 and IK180 from Brodix are 64cc combustion chambers. My stock heads were 64cc 083 castings, so this will keep my current compression ratio. I believe the trickflow heads, kenny duttweiler series come in different combustion chamber sizes, so you can find something that fits. You just have to look around, the info is out there.


As for the stock prom adjusting, I don't know much about it...all I know is that it doesnt take well to after market items like heads and cam, and there is ALOT of potential in a custom PROM burn, that will lean/richen out your A/F ratio to where it needs to be, so that you gain power, and your car runs better with the modifications you have done. I have heard very good things about PCMforless.com on this forum and on Camaroz28.com, and their dyno sheets do not lie. I will be getting a chip from them in the next few weeks after I do heads and cam (which are in the mail ) and I will post up my results.

My cost, with the Brodix IK200's, which are a great street/strip entry level aluminum head, and a huge step above stock castings flow wise (i did the math and looked up flow numbers) will be about $1100-$1200 when all is said and done with gaskets and whatnot. These heads are assembled, so springs, and things like that come with the head. You might need new pushrods to handle more power because stock ones may bend/break (i will be doing this). You can reuse your old rockers if you choose to do so. You will need gaskets too, which will be about 50$ for a good set. You may use your stock head bolts, or reuse the old ones. That price is for just a bare head swap alone with the necessities. Remember, the little things add up...sure the heads are only 1000$, but just keep in mind the other things.



AFR heads are a notch above, and so is the price. Don't get me wrong, Brodix makes expensive heads that flow even better than the IK series, but AFRs entry level head is 1300$ as opposed to 1000$. They do flow a little better, but one on a budget has to ask "is that 300$ worth it? Or can I buy my cam with that and stick with Brodix heads?". Remember, youd spend 1500$ alltogether with a set of AFR street heads, because of gaskets, pushrods, etc.


For the most part, with the exception of say: +/-100rpm, they will flow over the same rpm range, but with differences in HP being higher or lower at peak.

For example, in Desktop Dyno, the Brodix IK series heads made about 8 more HP in my application than the Trick Flow Kenny Duttwieler heads. The AFR street heads (1300$ ones) made about 8 more HP over my Brodix heads.

These numbers arent necessarily 100% accurate, but close...and the idea is there. AFR is top of the line, they flow better, so they will give you slightly more power. Brodix flows slightly better than TF, so they will make slightly more power...you see? DD is just a representation of the differences of these heads, a representation which is pretty close to what you would see in real life.


As far as the 113 castings getting machined out for flow and a bigger cam...there is potential there, but you won't see as good of numbers as you would with a set of aftermarkets (close, but not better, I would think. I've never seen dyno proven results that stockers flow better than aftermarket even when ported)...but again...you have to ask yourself: "is that difference in 600$ or so going to be worth 10-20hp? Can I put that money elsewhere?"



Hope this opens some closed doors for you. Feel more than free to shoot me a PM if you have any other questions/concerns.

Cheers
_Clark

 

That was really helpful info in a lot of ways.

I've spent untold hours over the past 6 months chasing down so many little mantainance issues and figuring out what parts to stockpile. It hasn't left me with much time to learn about intake/head flow patterns or to learn about PROM chips. I love fine tuning a vehicle and eventually will get to all the information to understand the 350 block internals.
Meanwhile, I've got to start coming up with a long term plan so I don't end up buying the same part twice or thrice because I didn't get the performance application right the first time. What I ultimately want to end up with is a car that I want to keep for the next 30 years and a drivetrain platform that will allow me road coarse abilities rather than just dragstrip numbers. I wish I knew enough to figure out how much horsepower and torque it will take to get this heavy car to Powerslide through corners without bogging down. THAT'S what I really need to figure out as a building base.

I'll order the PROM on Monday- Question: Since I live in Smog **** California territory; do you think I should keep my factory PROM for passing emission tests or just send in my original factory part. They seem to charge an extra $100 for a core charge. (My monthly budget is only $400 bucks a month, so an extra hundred dollars makes a difference in how soon I can buy another part)

Oh, one last thing: I havn't stopped to figure out what our stock compression ratio is on the L98 engine. Any idea how much higher I can go and still drive around in 112 degree weather with the A/C blasting without pinging???

(So Many Questions with To Little Brain Cells)
Again, major thanks for taking the time to answer me last post!! Nitro

 

I'm considering an LT4 cam and some new heads, obviously I'll need new springs and such too. The problem is finding a head setup that I can afford, if I can find a used setup that is GUARENTEE'D to work, then I'd definately be all over that deal... just a matter of having enough side money to be able to purchase the heads. I can obviously do it in steps, get the heads... save up again and get the cam... then save up again for labor(unless if I want to tackle the task). A PCMforless chip will run around $155 for everything... obviously I'd love to get a Dynotune, but a Dynotune will probably run around $500. I really can't justify a $350 difference for maybe a .1sec increase.

 

to me it sounds like the tranny is the big issue. In most cases shifting manually is slower then just putting it in D.

 

I read all through this long post and one thing I noticed that no one has pointed out yet is the fact that you're also running Flowtech headers. That's one more thing that's probably hindering your performance somewhat. IIRC the Flowtechs are only 1 1/2" primary tubes with a puny 2.5" collector. They're really affordable, and that's probably why. It should be against the law to throw a HSR on a motor with a stock cam and chip as well! At the very minimum, you need to upgrade your cam and valvesprings, port your stock heads until you can afford good aftermarket heads, get a custom prom chip, AFPR, and a better flowing exhaust system. I'm sure there's a lot of finer details that could use attention as well, but the above mentioned things should be mandatory. You've got a lot of tuning and wrenching ahead of you from the sounds of it, but as long as you do searches on this board and ask the very knowledgeable members here a lot of questions, you'll get everything running in great harmony eventually! After all, a member of this site made Car Craft magazine look like a bunch of novices on TPI engines recently! Just read the article in this month's issue on Don Lorentzen's T/A and you'll see what I'm talking about. Good luck!

 

I'm gonna agree with ZQ8Dude, first thing I would check is the transmission. I agree that he could do more mods to his engine setup to make more power (which would include a PROM) but thats only 1/2 the puzzle. The other 1/2 is getting that power to the ground, so drivetrain. You can make all the power in the world, if it dosnt get to the ground then it dosnt matter how much you make. Considering the transmission is already acting weird, thats where I would start first. Do you know how many miles are on the trans? Is it being properly maintained as far as fluid/filter changes? Is the TV cable adjusted properly? What kind of stall are you running? Once you verify the trans is working 100%, then I would focus on the engine. Whenever you doubt something with the engine I would always start mehanical, so do a compression test to make sure everything is still good internally. And along with that might as well change the plugs (since they gotta come out anyway). Once you know the mechanical aspect is good, then I would focus on the rest. Like these guys I would recommend a PROM change to account for your new mods. But me personally, I would do at least a cam change before re-tuning the PROM. And I would be sure to choose a Cam that compliments the HSR's powerband and matches whatever RPM stall converter you're using with that trans.

 

Hmm. Yeah that is slow for those mods. My 88 L-98 ran 14.21@98.5 bone stock with a 2.00 60 foot. Goodluck!!

 

I highly doubt that it is the headers that is holding him back this much, when other issues such as his finniky transmission, and stock heads and cam are still out there.

Read how many people ran better times than him with bone stock applications...that Includes stock exhaust manifolds. Guys are running up to a half second faster than him (including my old times) with stock manifolds. Besides, even though his may not be top of the line, it is at least SOME increase in flow over stock. Keep this in mind.




And I will also agree with ZQ8Dude, and Crazy Hawaiian about the transmission acting up. Explain to us EXACTLY your issue here so we can factor that into this equation. I know what it is like to have the power but not be able to put it on the road. It's called a 15.3, and its not fun =(. This was due to the fact that when I first got into this, I thought deflating my radial tires was a good idea at the track...wow was I wrong.

 

They Wont give you a new chip, you will have to ask for the adapter for a total of $150 so that you can put your stock chip back in whenever

Look at this link

Pricing

and scroll to "Custom Programming 1986 - 1993. They want 150$ for the tune, and they will send you an adapter, so your stock chip does not have to be sent in to get re-flashed, so you have no down time, and can put the stock one back in anytime. If you go for emissions, all you have to do is take the adapter out, and plug the chip directly into the computer. (Although your custom chip may give you a better A/F reading, which may equal cleaner emissions).


What heads do you have? I know that my L98 with 083 Iron castings has a 9.5:1 Compression Ratio. L98 engines in camaros were rated at 10:1 in 1991, and TPI engines with the corvette 58cc Aluminum heads had a 10:1 compression ratio.

 

The car has an aftermarket Hughes Performance 700r4 with tranny cooler and a B&M 2400rpm stall converter. The tranny was installed in '03, and from the day I bought the car(and with previous owner) the kick-down throttle never functioned properly. If you are in 3rd and cruising then slam on the gas... the car will stay in 3rd and accelerate from there, instead of dropping to 2nd. We pulled the tranny about a month ago to replace the flywheel and we also replaced all the fluids and filters, the original fluids and filter appeared to be in great shape. We did break the kickdown throttle cable but put in a new one... still doesn't auto downshift at full throttle, we even took the car to a tranny shop to have them look at it, they had no idea... unless if it had a 'clogged' valve or something, which the guy said would be very unlikely. The only thing I can do to make the car shift at higher rpm's and harder is adjust the kickdown throttle linkage, other than that, I have to do it manually to make the car really kick up and go.

 

The heads I have are whatever came factory with the 1988 engine.

I'm having my mechanic figure out an estimate this weekend for replacing the valve guide seals and will be able to compare that with just replacing the heads. Of coarse, I'd not stop at just new heads as I would have to do the cam at that time, plus with the heads off, I could go through the oil pan and pop in new pistons, I-Beams and bearings. Or at least I'm asuming that the pan can be dropped with the engine still bolted in.

That's always been a favorite repair item I've repeatedly done with some of my high mileage import commuter cars; just pull the pan and throw in new rod bearings as soon as I found any metal shavings in the oil filter.

I'm wondering now if my leaky valve guide seals would cause any compression leaks??????? I'm assuming it's the guides as once the vehicle has been started, as soon as I shut it off- withing minutes if needing to restart it, I get the cloud of smoke out the tail pipe. Initially there was so much raw fuel being dumped in from the sticking 9th injector/CSI that I didn't know there was a seperate issue.
Nitro

 

your TV is a big part about the tranny knowing when to change into gears. There are 3 ways that the tranny knows what gears to go into(speed sensor and 2 load sensors) if one misfunctions your tranny will stumble.

Fix the TV cable, and then run it at the strip. I garantee better times.

 

Ok first off, Cam-Aro:

There is a way to adjust the TV cable, and I dont know if you have done it yet. There is a link here that gives you an idea. If your TV cable has too much slack, your trans wont shift right. Found this out first hand when doing the shift kit.

https://www.thirdgen.org/detent

The way I did it was, I had someone in the car hold down the gas, and I adjusted it from the bracket in the rear using a flathead screwdriver, and made sure the cable was tight. This is what you want under WOT.




******************************************


Neagan:

As far as your valve stem seals getting fixed, I don't think that would be such an expensive job...well then again, it's a tedious job and will take a while so you might end up paying more than youd like. I think I'd rather put the money into a set of vortec heads.

And you arent losing compression from leaking valve guide seals, all that is happening is this:

Your seals are supposed to lock out oil that is applied to rockers and upper head valvetrain. When you shut the car off, the excess oil sinks to the bottom of the head, against the valve stem seals (which are supposed to block out oil from the chamber, remember). When these get shot, that excess oil is allowed to drip down to the bottom of the valve and it rests there until you start your car. So all this oil collects, and you start your car, and your valves open up. Along with that fuel and air is a little bit of oil, which is then combusted and spewed out your tailpipes.

So you see, you arent losing compression. Your combustion chamber is still sealed by the valves and rings. Therefore the only downside to this is a loss of oil over the long term, and maybe fouled plugs after a long time.


As far as doing a bottom end rebuild with the engine in the car.
I don't think you can just drop the oil pan down and remove the rotating assembly...you have the crossmember smack in the middle of the oil pan, remember? Unless you can get that down, what you do from there on is beyond me.

 

We know how to adjust it. If I go any tighter, the car will run up the RPM's higher and shift. If I make it any looser, the car will shift lower and softer. The problem is that when I made the TV tighter, the car would run the RPM's up to about 3000 before shifting... and that's at casual throttle. It'd bark the gears through 2nd when I was just cruising, but the kickdown throttle still didn't function right.

 

Thats so strange...

Well that kickdown cable leads to a metal rod that pushes a valve in the valve body in and out under acceleration/deceleration. The only thing I can think of is that maybe this rod is slipping out of the valve just a hair, or it is getting caugt on something. I wish I had a picture for reference for you but I don't beleive I do.

EDIT: Yes I do:


I know its a bad pic but it gives you the idea of what that TV cable is affecting.

 

I dont think I saw any mention of timing. What is your base timing?

 

I would contact Hughes Performance and see what hey have to say about the way the transmission is acting. Its unfortunate but waiting this long before saying anything decreases the chances of them helping, should have brought it up the first time it started acting weird. Its possible they made a mistake when building the transmission, wrong rod or something else wrong. I know when my guy built my TH350 he left out the kickdown bracket (but I didnt care).

 

Yea I would get your trans. taken care of then get a tune or learn how to do it your self and yes you can hurt your 1/4 mile times with a lot of mods and no tune trust me I was running 14.1 before a tune and now 13.6 after and I just did some more tunning on it so it should be 13.4 now so trust me a tune helps more then you think.

 

Would the TV cable need to be readjusted when putting on a new intake... like would the new intake(HSR) throttle body be located differently than the factory intake? Would this force me to need a new TV Cable? The tranny had the original TV cable with it when I got the car and it was still shifting wrong(maybe it was never tuned right, or the intake is off from the stock intake). Would a new TV cable come preadjusted if told what setup I have? Or would I have to tune practically all TV cables?