bud40oz

hi, just wondering, if 4:56 gears would be too much with the stock tire sizes on a 91 6 speed, also curious if the stock zr1 tires will fit with no problem i plan on buying new tires here this spring and i like the look of the bigger rear tire.

i already found the answer to my tires, it looks like you need the gs rear wheels with a 50 mm offset so they don't stick out past the wheel well. sounds like i need to call this house of wheels guy on that subject

i should also add that my car as i got it was already swapped from stock injection and intake system due to an engine fire from leaking fuel lines from the oirginal owner... to hei distributor and edelbrock torker 2 intake with an edelbrock carb, which will be getting swapped out again for a much better set up of performer rpm air gap and holly dual feed mechanical secondary carb, so the limited rpm of the stock fuel system is not a problem for me, sure i wish it had the stock fuel system but i bought this car for 500 dollars and i really cant see me spending thousands of dollars to put it all back to stock. this car will be a toy/hot rod for me not a daily driver, i will probably never drive it more than a 100 miles from home. it will be a street hot rod type cruiser that i put the top down and cruise around to lakes and have fun in, i know from past builds and cars i have owned. you can dump a ton of money trying to get that extra hp but the main thing to make the car throw you back in the seat is gearing,

65Z01

Does it now have the stock 3.07s?

Switching from TPI to carb will lose that low end torque so maybe 4.56s won't be too bad to drive on streets.

bjankuski

Too much gear in my opinion, 4.11 max. The tires are small diameter so it will be too rev happy with the 4.56 gears.At 6000 rpm you will be at 100 mph in 4th gear, and have to shift to overdrive. It will work but I think 4.11 would be better.

Rob Burich

Mate. I just recently ordered a complete zr1 centre fully reco with 4:88 everythings brandnew with a Dennys 1350 pinion yoke. But ive decided to go 9" ford rear. So if you wanf it cheap cheap. Make an offer. It was built by corvette parts online in florida. They specialize in corvettes . If interested message me. Never run or used. Ive just put a 632ci bbc in mine. I dont wanna risk it. Cheers bro

bud40oz

its stock 3.45 now with dana 44.. zf 6 speed

ex-x-fire

I think if you add 4.56s you'll basically have a 5 speed with a granny gear.

tequilaboy

If car is already:

1. Slow/under-powered and will trap < 110 mph
2. Capable of 7,000 rpm despite being slow
3. Not traction limited despite being slow (full slicks)

Its not all that crazy.

Use 811 rev/mile for tire size. Need about 6800 rpm to reach 60 mph in 2nd gear and trap in 4th at 110 mph. My Evo has more gear than this (stock drivetrain) but can turn 7500 rpm prior to fuel cut. Its also slow/under-powered (~350 whp) and is not traction limited (awd) by my standards.

Now if you want to use a 28" tire (720 rev/mile), that changes things and becomes quite a bit more reasonable.

Check out the gear chart and play around with gear and tire size to give you an idea.

http://www.pszweb.com/car/gears.htm

Side note: I thought the Torker II was a pretty decent single plane back in the 80s (up to 6k rpm). Not sure a dual plane would really improve upon it for what you're doing, but I'm out of touch with what's going on with carbs these days. For 7k rpm, probably want a big single plane.

bjankuski

I think the engine is stock besides intake and carb. I do not think the cam or heads will make power after 5500 RPM and the bottom end will self destruct at 7000 RPM. If the engine is capable of 7000 RPM for life and power then 4.56 gears are OK.

KyleF

Even witht he 6-speed, that is just too much gear.

You car will "feel" like a monster. The tires will brake loose a lot, it will be difficult to drive... oh and it will be slower int he 1/4 mile.

The TPI's short power band just runs out of breath to use a lot of gear.

I usually say nobody ever regrets going to low... but you are way over the deep end here. A factory TPI manifold loves a 3.4X/3.5X gear... 3.73 is pushing it. If you are willing to change to a mini ram or other style manifold, then the 4.56gears will work. Still a lot of gear for a street car though unless you are also doing traction mods.

bjankuski

As stated on first post, carb and torker II intake.

tequilaboy

In the event that it is not already apparent that this is a bad idea: the downstream parts (spider gears, side gears, half-shafts, u-joints and stub-axles) won't live long due to the torque multiplication. Blowing stuff up always makes for good stories, though.

bud40oz

the 4.11's would be a better choice probably, those dana 44 rear ends are a pig type aren't they so s guy could just get a whole new pig set up with different gear rations and swap them out real easy?..
and yes i also thought the torker 2 intake was a good one back in the day,. i was happy to see it on there until started reading and there is nothing really good said about them lol. in fact i read one place, worst intake ever made even..but who knows. i like the x style intakes myself hell its free and already there, maybe i will use it for now and spend money in other areas like gears.. 500 bucks for the polished rpm air gap would buy a set of gears. i dont really care about the engine in it now. i mean sure it runs, but its nothing really awesome by any means.. 250 hp 345 torque those are 6 cylinder numbers on today's standards. . i will blow the guts right out of that L 98 n build a roller 400 old school small block next winter

cv67

most complaints were from people who shouldnt have had one on their car in the first placeI

op gear the car for the cam not mpg or cruise rpm & youll be happy. Too many think they want some big cam, tall gear then complain it acts...like a big cam esp when they drive it like a granny.

KyleF

Yup missed that... and that is not staying anyway... RPM Air Gap and Holley.

What Cam is in it? Does it match the RPM range of the manifold? What Heads? You need to match these up for best performance. The L98 Heads/Cam won't pull to the stated RPMs of the intake and carb and your car will run out of breath fast!

4.56 is too much gear, with a ZF that is 12.22 multiplication in first compared to 9.48 with a 3.54, almost a 30% increase in torque multiplication... not just 30% more torque. You said you were going with ZR1 wheels. That is only about 26-1/4" in diameter(P315-35/17). If your cam matches the intake... which it doesn't if it has the L98 Cam in it, and can run to 6500RPMs in first, you will only get to 42mph (Which isn't bad I suppose), then shift to 2nd and hit 4400 RPMs, pull to 6500 and 62mph, then shift into 3rd at 4700 RPMs.... not a good spread for pulling and you will spend a lot of time shifting. Now 3rd extends to 86 and will shift to 4th at 5000RPMs and pull to 6500 RPMs an only be at 111mph.

This does not look like a good scenario on the stock L98 Cam, and even if you have a 6500RPM screaming 400... you will probably want to trap at a higher mph than 111mph.

Looking at it with 4.11's, You can get to 96mph in 3rd... so basically only 2 shifts to get to 100, and could trap as high as 123mph in 4th without adding an extra shift. This is assuming you have peak hp at 6500RPMs.

The real big question is going to be traction. My Viper had the 335's, a T56 and a 3.55 rear. Traction was a joke. I could break the tires loose anywhere in first gear. This was an older Viper with long intake runners and massive amounts of low end torque.

bud40oz

i am quickly seeing that this car, will not be very stock for long, i am fine with that, my wallet not so much..i understand how the cam and gears and all work, i have been playing with cars for 35 years. i think i will go with 4.11's eventually like i said i would really like to find one set up with all new stuff where i can just swap it out. the cam i have been eyeing up is the lunati vodoo series some where around 510 int 530 exhaust i think. not real crazy just a nice sound at the street light, The problem is though,bigger cam turns into heads not flowing enough and that turns into a compression loss after you change those, so then ur buying new forged flat top or even domed pistons.. then you mays well not half *** it at that point and go with a nice steel crank, and good rods.. and for that matter by now you may's well buy and msd ignition..... decisions, decisions i just need to figure out a starting and ending point for this 500 dollar car. to be honest it's seeming like i should just part the thing out and make a few bucks compared to being a big huge money pit, i really wanted a 1970 split bumper camaro anyway

KyleF

Are you stating that to qualify why you asked if 4.56 Gears are too much?

Yes, it is always good to lay out a plan. For $500, it wouldn't hurt my feelings at all to ditch the complete running gear and start with a stated goal and build the chassis to handle the motor, and then been a motor to deliver what I want.


This is how I feel about IROC's. I have always loved them and will never go without having one in the garage. If times get tough, the Corvette will depart first. It's nto that I don't love my 'Vette, it's just my heart lies with F-bodys. I have had so many different cars, but always come home to thirdgens. My advice, build on a platform you already love. You will enjoy it more.

I am not sure any project car or build can avoid the money pit status. You will spend the money on something, might as well be on a dream car.

bud40oz

well i just know you get a lot of performance from a good gear ratio. sure 3.45 is fair. but i plan on changing the gears, i was actually looking at prices on the 4.11's and saw a 4.56 set for the same price, that's why i wanted people's thoughts. i'm sure someone here has done both of them before. also knowing the stock injection system has much more torque than what i have now as the car is sitting with the carb and torker 2 intake, i figure the gears would make up that difference in performance as far as hitting the gas and getting pushed back in the seat. I'm all over the place right now with this car. i want everything all at once i guess and looking at the costs to do everything i want i am getting discouraged. i am not a rich person, only reason i got this car was because it was 500 bucks. i might be the only corvette owner to pull up to a soup line in a vette lol no i am not that poor but you get the idea. i guess it will be a fun project and just take it one part at a time like most other hot rods. its not an instant build for most

KyleF

The cheapest route I can think of is just run a carbed 350 with vacuum advanced distributor. Some things won't work with the dash (I believe), but you should be able to pick up a used built small block cheap. You should be able to have a lot of fun on the cheap that way. It won't be a nice finished car with everything working, but that doesn't seem to be your goal with this car anyway.

383vett

Everything on the dash works except the mpg readout. Been there, done that.

bud40oz

actually, everything on the dash works just fine, all gauges tach spedo, radio heater so on, all works. it really is a very clean car. the guy used to take it to car shows before the fire incident, then they did the carb swap and i don't think they really knew what they were doing and it sat for a few years. power seats do not work on either side.. but power windows do work, and the key fob doesnt make the power locks work, not sure it they work by the buttons. i have actually only had a few hours to inspect the car totally bought it on my birthday last november 19'th for 500 bucks and it has sat in the garage ever since, i will get on it soon as the warm weather hits us in michigan here. its a long ways from a pile of junk. it is a very clean car... i have the missing panel i just leave it off because i disconnect the battery while it sits... its all black leather interior black top and black paint, think thats called triple black? they chopped a nasty hole in the hood for the carb but he gave me a fiberglass L88 hood scoop which i plan on doing some custom firberglass work and some cutting and wrapping to make it fit the hood and blend in together.. i sorta like how it looks sitting on there, it makes it look almost like an older c 3 from the side profile in the front, the rims i see are on backwards in the front he had a set of aftermarket wheels on it while he drove it, but he wasnt letting those go for the 500 bucks