Well, with a whining 10 bolt, a 6 speed with only 5 working gears and an engine with something messed up with the bottom end, I had to do some serious thinking. And unfortuantly, my camaro is rotting away on the underside. After looking at all the options, looking into a buying another thirdgen was the best choice, and I can take the time to do it completely right this time.

Anyways, I ended up finding a very clean '91 RS with 80k on the clock/305. It does have T-Tops, which is kind of a downside for my application, but they have their plusses as well.

The only mods I have done so far are the open element, underdrive crank, 6* advance timing, and removal of the spare tire and jack. These simple and cheap mods have really made for a SOTP difference. I don't plan on too much more with the 305, but I will put the MSD coil and aluminum ds in these week, as well as doing the ultimate tbi mods to the stock tbi (now I'm glad I held on to it!)off my old camaro in hopes to gain some more pull up high.

Anyways, on the the interesting stuff........planned mods: Let me know what you guys think:

383: Bottom end rebuild/inspection, more bowl work on the heads, and installing my 1.6 aliminum rr in place of the 1.5s I had on there. Stock style motor mounts.

T-56: Either rebuild or d&d performance t-56 rated at 500ft/tq.

Rear: Strange 9" with 12 bolt gear setup. Posi (not sure which) w/3.42s

Reusing the spec stage 3 clutch, but hopefully going with a aluminum flywheel if in the budget, reusing the poly tran mount and spohn crossmember and adustable torque arm.

Hotchkis 1" drop springs, Koni adjustable shocks (have), Lakewood LCAs (have), LCA relocation brackets, TDS Wonder bar(have), KB subframes, poly bushings all around.

Exhuast: I would like to go with the Hooker super comps, but they seem like they might be more pain then anything with the t-56, as well as lowering the car. I think I'll probably go with coated 2055's with an electronic cutout precat, and a borla single 3" exhaust.
Let me know what you guys think on the header selection.

Odds and ends: Digital MSD 6, NGK plugs, MSD 8.5s, Mobil Synthetic, Prominator, 255/50/16s in the rear, smog delete, ram air setup(have),injector cleaning, Cervini cowl(have), and fuel tank w/ walbro 255 pump from the old camaro.

I will be reusing my modded holley 670 setup, and should have pics soon, since it will be off the car.

Let me know what you guys think, and please input any ideas. I am really iffy about lowering it, as I am more interested in the drag aspect as opposed to autocross.

 

Thats a great set-up but I assume you posted it because you are retaining your 670 TBI? You should have a killer TBI set up once it is all put together and tuned. I geuss you will test the tru limits of the 670 unit with your new combo

 

Well, the combo isn't all that new, but I do hope to test the limits of the 2bbl tbi again, hopefully with real numbers this go around. The engine setup will be the same, minus the 1.6rr, but I am really looking foward to tuning with the Prominator in hopes to reach the full potential of the setup. I was never able to get over a false knock problem, and thus my timing chart wasn't even as aggresive as a stock tune port vette. I guess the only main changes from my old setup is hopefully an aluminum flywheel, and the 3.42s as opposed to the 3.73s I had.

I have raced my buddies 12.7 sec mustang numerous times and have beat him everytime, even with very little traction. I am hoping the 3.42s help traction w/ street tires while staying in gear a little longer. I can honestly say 11 sec quarters are possible with the 2bbl tbi, and this car will be there.

Do you know which pin setup I need for the prominator?

 

Sorry I am not familiar with the prominator set-up. The DIY PROM guys may know.

 

what do you mean by pin-setup?

aslo, with a T56, i would run more than 3.42's i have always thought that 3.90 would be just about right for a T56.

another though if you are going to get a new tranny, what would you let the bum t56 go for?

the combo looks good, i can't recal what cam you have, but if you put something in the 230* range in there, and a 4bbl TBI unit, i bet 450 crank HP is very doable from setup. as much as i would like to see people push the limits , i really think that with the big cubes, if you cam it for much power, you are going to need step up into a 4bbl unit.

 

This is the cam the engine's got in it: Comp 305-8: dur. 220/230 lift .510/.510 LSA 114

Good luck with the rebuilt setup r90, are you hoping to have it up and running this summer?

 

i think something like the lunati 01-HR14-HR15-10-A01 would be a nice touch in that motor, with a 4bbl unit.

230/238 .530 .530 114

 

Gee, kinda sounds like my car. Ghetto rigged 9-bolt with a 700-R4 that has zero forward speeds under WOT.

I dont know if the springs will lower the car all that much. The stock rs springs are kinda mushy and usually sagging alittle to begin with so the actual loaded ride hight will probably be about the same. Although, the stiffer springs will effect the cars ability to roll about its instantanious center when you launch so they may effect the cars ability to transfer weight to the rear wheels under load.

 

you want the stiffer rear springs, you want weight transfer, you get that by unloading the front, and the momentum moving forward. you don't want the rear to squat, that will cause wheel hop.

 

Ok, spoke without thinking...

I can see why rear squat is undesirable because of moving the IC as well as causing wheel hop, but, what actually induces the usprung mass to hop? Ive never been real clear on what initially sets wheel hop in motion. Is it just the rapid upward motion of the rear? I used to have real bad wheel hop problems with low compliance racing tires, but with tires that are more compliant, the problem vanished and the car launches quite nicely on the street.

 

Wheel hop is caused when you load the suspension in a mannor the shocks and springs lose control. They become an unballanced system and do not perform the way they are supposed to. In essecne the shock cannot control the rate of the srping compression and it bounces up and down. The shock will just go along for the ride.

 

hmmm... to my understanding, and the way it was taught to me, the tires are the dominating force in wheel hop since the 'spring' rate of the tire is so much higher then that of the springs taht support the chassis. From there on in, the effect pretty much jsut involves the tires, shocks, and the rear as the system and the whole thing jsut bounces up and down with the chassis springs providing the downward restoring force. I was never clear on what actually set the whole thing in motion and drove it to begin ocillating.

 

Yea you are right and thats what causes the force overload if you will. The tire will rebound at a much greater force than the suspension can tolerate and than oscilation is a result.

 

Thank you for the responses.

I'm going with the 3.42s for a few reasons. The main reason is that 4th gear is still a 1:1 ratio, and I plan on trap speeds of around 120+mph (albiet after a commander 95o 900cfm swap down the road). The 3.73s with 255/60/15s yielded 118 mph at 5,500rpm. Also, even after suspension mods and nice street tires, I am sure this thing is still going to lack traction. The 3.42s should help cut back on that a little. But like you said dewey, the .5 overdrive in 6th would still make for nice highway rpms.

The cam, after 1.6 rockers will yield a .544" lift. If I were to swap cams, I think I would go one step up to the cc 306-8. I think the specs are 228/238 dur, .510/.525" lift (w/ 1.5 rockers), and 112 LSA. But I will probably stick with the one I have, as I am very pleased with the power/powerband, and think it fits my combo of protopline vortecs and rpm airgap well.

The rs springs are spongy, I hate the body roll! I will end up going with the hotchkis springs then as long as they are'nt going to drop me any more than an inch. Also, I'm pretty confident in my planned suspension setup, I just have to deside on front struts now.

I'm going to get a price on the t-56 rebuild soon, so I will know soon what the situation is on that, and can shoot you a price and what all needs to be done. Keep in mind I have to keep all the odds and ends off of it like bellhousing, slave/master cylinder, etc.

Bron,

I hope to have it going this summer, but it all depends on how much everything costs. I will definetely have the car out at 66 though, albiet with the 305 next month. Definetely let me know when your headed out there.

Any ideas on headers guys? I currently have the hedman TES headers, but am unsatisfide with them. Also, this time around, I am going air tube free, those things only got in the way!

 

A stiffer front sway bar will help as well. Like maybe one from a 1LE car. If your really into road setups, you can really balance the cars handling by varying the stiffness of the sway bars.

 

You could really benifit from some SLP's with the 1 3/4" primaries. My next suggestion would be long tubes with custom ypipe. I geuss we should get this back to TBI related. I am just as guilty as you guys on this. Lets try to let the suspension stuff rest and focus on his awesome TBI plan.

 

I think I will go with the hooker long tubes, especially if the hotchkis springs won't effect ride hieght too much. My main concern was ground clearence-but I'll have to do some research on the starter issue- LT1 starters are expensive!!!

I think the long tubes should compliment my tbi set up well. I realize I will lose some lowend torque, but I am willing to trade that for more hp.

One of my goals is to see how deep into the rpms the 2bbl will go while making good power, and I think the LTs will compliment that.

 

You will probably gain low end torque not lose it with the long tube headers.

Steve

 

More low end torque! I don't know what to do with the torque I have! Just joking, it sounds good.

On a 305 side note, and a warning to others-I tried to remove the torque bits for the blades on my old tbi, and the heads twisted off. It may be because the thing has been sitting unused for 2 years though, but still something to keep an eye out for.

Also, does anybody know of a place I can send my injectors out to to have professionally cleaned?

 

Turbo City has an exchange program for stock GM injectors.

Don't know if they will clean the Holleys, though.

 

Make sure you use a heated 02 if you go with longtubes. TBI systems get awefull goofy if the 02 is not is hot as it should be.

 

If you flip the injector over and look in the nozzle that should pretty much tell you if they need cleaning. If the inside of the nozzle looks to be deposit free and they dont leak then cleaning isnt really necessary IMHO. Thats pretty much the only part of the injector that can get fouled up. The pintle inside them is really too large to be affected by minor deposits. I did ultrasonically clean my 15 year old stock ones and I didnt really notice any diference at all since they where already pretty clean to start with.

 

Thank you for the replies guys.

Though I really would like to go with the long tubes, I'll probably go with the hooker 2055s from ACS. After yanking the tranny today, and doing some $$ figuring, LTs are just going to be too expensive in the end. A rough figure would look like this:

Headers coated/shipped: $700
Heated 3 wire o2: $100
new LT1 starter: $130
custom y-pipe(mandrel): $150?
misc. grinding to make work with t-56: More headaches!

Also, I am hoping to make peak hp around 6,000. I realize that may not happen with the 2bbl tbi on there, but I do plan on swapping to a commander 950 4bbl tbi eventually (albiet a ways down the road), and from what I gather, shorties are actually better for higher rpm hp. And though I do eventually want to run a heated o2 to the ecm and a wideband for tuning, I can get away with using the stock single wire o2 for a while.

Also, just incase anybody was wondering.....I am not reusing the hedmans for a few reasons, namely because they are uncoated and have the air pipes on there(I will have them removed at ACS on the 2055's), but also because of a few other reasons.

 

Eh, the verdict is still out on that. But for your combo long tubes would make the most power over every RPM power point. You cannot go wrong with the 2055's though.

 

Dimented,

My 85pph delphis aren't spraying the way they should. But they also only have about 7k miles on them. Any ideas on what it could be? I'm going to replace the o rings again to cure a minor drip on one side, but both spay all over the place. Could it be the screens? I have had some backfire through the tbi though, so I guess it is possible that could have spewed something up into the injectors. I will have to check them when I pull the tbi.

 

You might want to send your injectors to get flow matched. They are sloppy in stock form. The back-firing through the TBI is a timing issue.

 

Thats kinda what I was thinking. The LS1s make the best power with longtubes, and they have a redline similar to my setup. Man, I would really like to go with the LTs, but like you said, the 2055's are still a great choice. Who knows, maybe down the road, LTs will go on there.


Another question for you guys-kinda exhaust related, but ties into tbis power as well I guess...... single 3" or 3 1/2"? I know the 2055's y into a 3", but that can be changed. Would it be benificial to go 3 1/2" or would it be over kill? I will be running a cutout just before the cat.

 

Stay with 3" for now. You really need some wicked exhaust flow and velocity to truly max out a 3". I doubt you will do that with a 2bbl TBI. A 3" can support 400hp to the wheels with ease before it becomes a restriction.

 

Sweet. That is what I wanted to hear. 3 1/2" would be pricey as well.

I will have to give turbo city a call and see if they will flow match my injectors.