SLP Cold air intake....Worth the money?

[Vette73]

Anybody have any experience using the SLP cold air intake ?I have had good experiences using just the plain K&N air filter...


My car is stock now.....Looking to do a chip,exhaust and maybe some gears
Down the road.....Thinking of buying this unit....


Any suggestions?


Thank you...

[Vette73]

Anybody have any experience with this cold air intake?

What are the real horsepower gains? Any difference in torque? Looking
To do a chip, exhaust and this if it's any good for now....Maybe some gears down the line....
Thank you.....

[Kevin]

to put it bluntly, no. a stock box with a cut lid and a clean paper filter flows just fine.

[GOLDCYLON]

I thought Locobob had some data on this..

Yep here you go about 1 to 2 HP

http://www.zr1.net/forum/showthread.php?t=17159&highlight=claw

[Kevin]

Didn't Marc say there was no difference at all? 1-2hp is within dyno error anyway

[GOLDCYLON]

Didn't Marc say there was no difference at all? 1-2hp is within dyno error anyway


Honestly for this small of a difference anything is possible to include dyno error. Now if it was 15 - 20 hp now we are talking

[XfireZ51]

Anybody have any experience with this cold air intake?

What are the real horsepower gains? Any difference in torque? Looking
To do a chip, exhaust and this if it's any good for now....Maybe some gears down the line....
Thank you.....

Stiffening the stock air bridge will net u more power.

[edram454]

modify your current air cleaner holder. ebay sells modified air cleaner lids that are very free flowing and work good with K&N air filters. dont waste your money on the slp unit.

ed ramos #3028

[Paul Workman]

For a comprehensive take on what adds hp, this form Marc Haibeck's web site will shed some light on performance mods...

ZR-1 Specialist

An aluminum insert for the air bridge will keep the plastic bridge from collapsing, thus pinching of air flow; more of a preventative measure than a HP adder.

I would suggest looking at Marc's list of modifications and establishing a master plan, rather than succumb to the considerable gadget HP hype so prevalent in our hobby. Just sayin!

[Vette73]

I figured as much....Thanks for all the replies..
In the past I have used a plain K&N filter and I did
Get some results,slight,but none the less,results..

[c4koh]

Vette73 - a Marc Haibeck chip comes highly recommended (I have had 2 in my current and previous ZR1s), and this certainly helps... next would be exhaust imho as bang for buck and easy to do... K&N air filter helps, yes, but so does a clean filter.

[Paul Workman]

Vette73 - a Marc Haibeck chip comes highly recommended (I have had 2 in my current and previous ZR1s), and this certainly helps... next would be exhaust imho as bang for buck and easy to do... K&N air filter helps, yes, but so does a clean filter.

I respectfully disagree. The LT5 utilizes a MAP based engine management; not a MAF. Therefore they are much less tolerant of that type of modification w/o a tune.

Anything done to change or improve the air in or out, really requires tweaking of the calibration. So, to buy a "chip" from Marc or anybody, and then go out and install headers, or do some porting, etc, the tune is affected. Buy the chip WITH the calibration for headers BEFORE installing the headers, was my point.

[Vette73]

MyZR 1 came the other day from gateway classics in Chicago...
Never in my life did I buy a car sight unseen....

I have to say the car is super clean...Really really nice Black ZR 1..

If you google gateway classics corvette # 633 you can
See it.....I think it's still on the website, a video also..

I would def like to do some mods to the car..However,never
Had a car with this much technology...My 73 convertible
Is super clean and I have a worked 350 in that..

I'm looking for low end and throttle response with the ZR 1..

I won't be doing any real high speed driving...I mean,
At times I will punch it on the highway but not crazy..

I see a few of you have conflicting theories on
Modifications ....I had the car out today and it's
Got balls,it does ....

My thoughts are.....Chip,cat back exhaust,
Hi flow air filter,Allthough I checked-there is an
Amsoil filter in there already, and maybe some gears
After the winter....

Any input is appreciated....

Tried loading some pictures of car in my album
But photos did not upload...

[5ABI VT]

I recommend a green filter. I don't use k&n anymore. Green uses a better filtering method although similar and I don't mind giving up a tiny bit of power if any for slightly better filtering and still flowing much more than stock.

As for low end torque, perhaps you bought the wrong car !! With long gears (same as LT1) the LT5 in my opinion will always gain more up top with mods like porting and headers etc. I don't personally like gears... but if you want more snapping torque... 3.73s or 4.10s are my suggestion.

I have a long thread not sure if most will interest you but I did headers and exhaust in there and Im really happy with the gains.
http://www.corvetteforum.com/forums/c4-zr-1-discussion/3300001-admiral-94-comes-home-finally-let-the-mods-begin.html

[Kevin]

I respectfully disagree. The LT5 utilizes a MAP based engine management; not a MAF. Therefore they are much less tolerant of that type of modification w/o a tune.

Anything done to change or improve the air in or out, really requires tweaking of the calibration. So, to buy a "chip" from Marc or anybody, and then go out and install headers, or do some porting, etc, the tune is affected. Buy the chip WITH the calibration for headers BEFORE installing the headers, was my point.

headers yes, exhaust you don't really need a tune for

[Vette73]

Well I wouldn't say the car has no torque, I mean 370
Ft lbs is not that bad...Granted it's up in the RPM range,
But after driving this car most of the day today and really not
Taking it past 5,500 rpm I am happy with it..

Response is nice and when you hit that gas it moves...

My 73 has 390 ft lbs in the crank at 3200 rpm so
There's a good amount of torque in that motor..

A big reason why I bought the car is you just don't
See them AT ALL.......The little characteristics that make
It unique attracted me...The wide rear , the slightly wider
Doors and the huge tires in the rear...

Very nice blue color on your car....Very unique..

[Kevin]

the zr-1 makes over 350 ftlbs of torque at 3000 rpm and around 320 ftlbs at around 2000 rpm. It doesn't feel like it but it has 300ftlbs at 1000rpm

[Locobob]

Dyno graph from my testing years ago: Average torque up 3, average hp up 5

http://i418.photobucket.com/albums/pp270/locobob68/dynos/368dynoairintakecomp.jpg (http://s418.photobucket.com/user/locobob68/media/dynos/368dynoairintakecomp.jpg.html)

[Locobob]

Headers, exhaust, intake porting are the big three power adders that don't involve buckets of money and intrusive engine work. A tuned chip makes the most of the big three.

[edram454]

Headers, exhaust, intake porting are the big three power adders that don't involve buckets of money and intrusive engine work. A tuned chip makes the most of the big three.

This is correct. You would be very happy with these mods on your car. Dont blow money on your gears either. It will impact your top end speed which is where these cars shine and the grunt off the line with the 4.10 gears will just result in spinning tires. I have the stock 3.45 and a bunch of mods and it gets off the line just fine. Once you have the those mods done maybe a fidanza flywheel so you can rev up much faster.

ed ramos #3028:-D

[Locobob]

This is correct. You would be very happy with these mods on your car. Dont blow money on your gears either. It will impact your top end speed which is where these cars shine and the grunt off the line with the 4.10 gears will just result in spinning tires. I have the stock 3.45 and a bunch of mods and it gets off the line just fine. Once you have the those mods done maybe a fidanza flywheel so you can rev up much faster.

ed ramos #3028:-D

I tend to agree, think of gears as something you use to tune the car to your driving purpose/style, not as a hp adder. Try driving someone elses car with gears first if you can, one size does not fit all.

[PhillipsLT5]

I went 181.3 in 1.5 mile with 4.10's, still had more to go, but no more runway

[Locobob]

I went 181.3 in 1.5 mile with 4.10's, still had more to go, but no more runway

I went 181mph with 4.10's once... but traffic kept me from going any faster lol. One thing I didn't like about the 4.10's was that I had to shift into 4th right at the end of the quarter mile, now I have 3.33's and the quarter gets done in three gears with no pedal modulation in first (street tires). And the car can see its true top speed in 5th - somewhere north of 2 bills - should I ever get the nerve to try.

[Paul Workman]

As it happens, my wife Ami has a 69 C3 with a cam/headers 350 L46 with a 411 differential - pretty close to your C3 setup, I guess. But, you can ask =Jeff= about a little experience I had, attempting to leave his stock 91(?) ZR-1 in the dust. To say there is NO comparison between a early 70s 350 C3 and a ZR-1 would be a gross understatement beyond any doubt!!

Ami also has a ZR-1 which happens to have cams and 410s. That car is WICKED on the street or highways!:dancing

I'd think about gears before tearing into the drive train - at least for the first year. That way you'll have a better idea of what changes you want to make; gears or what all else!

[Vette73]

350 L 46 was the 350 horse version with 11:1 compression
Back in the day I think.....It's true,modern technology
Replaces anything from way back...Maybe,maybe an L-88 or a Buick
GS Stage one in the quarter mile will do damage..

Yes, before tearing into the driveline I will drive the car
And get familiar with it.....It's funny the day the car arrived
It was at dusk..Rainy windy and damp it was..So much for
Seeing it arrive in bright sunshine or even taking a small
Video.....Lol...

As far as the speed you guys are getting out of your cars,that's
Impressive.....Fastest I ever went was on a motorcycle..
163 on my GSXR-1100 back in the real early
Nineties.....I visited that speed many times on Ocean Pkwy
In Long Island....Have not been back since ...
The bike days are over for me as of now..

[Paul Workman]

350 L 46 was the 350 horse version with 11:1 compression
Back in the day I think.....It's true,modern technology
Replaces anything from way back...Maybe,maybe an L-88 or a Buick
GS Stage one in the quarter mile will do damage..

Yes, before tearing into the driveline I will drive the car
And get familiar with it.....It's funny the day the car arrived
It was at dusk..Rainy windy and damp it was..So much for
Seeing it arrive in bright sunshine or even taking a small
Video.....Lol...

As far as the speed you guys are getting out of your cars,that's
Impressive.....Fastest I ever went was on a motorcycle..
163 on my GSXR-1100 back in the real early
Nineties.....I visited that speed many times on Ocean Pkwy
In Long Island....Have not been back since ...
The bike days are over for me as of now..

Yep, you know your C3s. However, after driving your Z for a year, you'll come to understand the 4-valve DOHC's virtues too. I recon you'll be hooked like the rest of us! Oh, and if you have any doubts, maybe you can meet up with Frank and get a ride in his 441 LT5, built by Marc Haibeck. That will put the frosting on the cake!!:cheers:

Enjoy your Z. When are we going to see some pictures.

[Bob Eyres]

Dont blow money on your gears either. It will impact your top end speed which is where these cars shine and the grunt off the line with the 4.10 gears will just result in spinning tires. I have the stock 3.45 and a bunch of mods and it gets off the line just fine. Once you have the those mods done maybe a fidanza flywheel so you can rev up much faster.

ed ramos #3028:-D

The old "gears" controversy comes back every time performance is discussed.
My take has always been that the ZR-1, stock, is way over geared for pure performance.
4.10 gears are a good choice for the quarter mile because they allow you to use the full range of rpm. Actually 4.30's are theoretically better.
In the 1/4 mi., or top-end, it's where you top out in top gear that counts. A three speed ZR-1 is not preferable to a four speed in a drag race. It spends too much time under it's best power range.
If you spin your tires at launch, you have a tire problem.
And at top-end a ZR-1with 4.10's in fifth gear will not reach red line before it reaches 180mph.. The vast majority of ZR-1's will never see 180mph. anyway.
JMHO, others will certainly differ.

[Vette73]

Sound like you have a nice set up Bob..
Using the car stock for now....Once the northeast
Winter is about done I will do some mods..

Thanks for all the input....

[edram454]

Everybody has a preference in gears. I would not want to put on some very sticky drag radials wtih 4.10 or 4.30 gears then rev her up to 5 or 6k and dump the clutch.... these are street cars not professional drag race machines. I dont think a zr1 can take too many of those launches. I dont want to hook so hard that I stress the heck out of my drive train. I have seen more than my share of corvettes spill there guts on the starting lines.

I have the following mods: Jeal ported plenum and injector housings,ported 63 throttle body,z industries chip,drm ceramic coated headers with no cats or resonators flowing out to 2 chamber 40 series flowmaster mufflers, throttle body bypass,MAT relocation, grand sport brakes vbp drilled/slotted rotors/hawk race pads, brake bias, drm roll bar chassis stiffner, camber brace, new paint, weather stripping,carpeting, gauge cluster rebuilt,all vacuum actuators replaced, radio and all bose speakers rebuilt, all ac system new with r134, new plugs wires and hoses. modified open air element and stiffened and lined air duct.. previous owner prepared this for the track and ran it a few times. I am running deep dish amolds 315's on all fours. stock 3.45 gears.

[Vette73]

Wow....Sounds like a healthy ride...
I just picked up my ZR 1 last week...Furst one I have
Owned ( pictures in my album)...

I have a C 3 with a good amount of work to it so
It's a torquey street machine, also have flowmasters
On mine....

Since I guess the ZR1 has long gears and a 6 speed
You can get away with putting a bigger rear in it without
Stressing the motor, that's my guess...

I am a new comer here and I see a lot if members with the
4:10 set up,even that guy Chip Healbreck
Mentions them...

Down the line I will see about going w gears, reson
Being I don't see myself consistently going
130-150 MPH on a steady basis....My driving is mainly
3-4,500 rpm range....Now, that's a lot on my C 3, even though that's
The powerband I'm rarely above 3,000..

My first few mods will most likely be a full system
W headers ....I hear OBX is cost effective and
Not that loud, which is what I'm looking for..
A chip, high flow air filter ( there's one in there )
And hurst shifter ( can't stand stock shifters)

[Vette73]

Hello..Edram454

What's up with the shifter? I will take it if nobody
Has beaten me to it...
You can PM me..

(Help a new guy out) lol..

[edram454]

Good choices. exhaust is always a good place to start. the modified air lid is another way. I have had a few c3's and I like them quite a bit. I had small blocks and a big block car. 4.10 gears might be for you. Many people have them and seem to like them. Zr1's are unique cars and I am sure you will come to appreciate that the more you own it.

ed ramos #3028

[Fully Vetted]

I prefer 3.90's. Gives you the low end grunt you're looking for and keeps you in 4th gear in the 1/4.

[Hog]

I prefer 3.90's. Gives you the low end grunt you're looking for and keeps you in 4th gear in the 1/4.
Is there not enough revs to complete the 1/4 mile in 4th?

[USAZR1]

Is there not enough revs to complete the 1/4 mile in 4th?

4.10's are good for 130mph in 4th. I'm sure David's ZR-1 is fast in the 1/4 but it isn't that fast.(unless he's running a 250 shot) ;)

[KILLSHOTS]

If you're basing your choice of gear ratio solely upon trap speed, then it seems to me that your ZR-1 is now just a drag car and you should probably get busy gutting your interior to save weight.

But, if you're considering a gear change for a DRIVER, then overall driveability should most probably be your major consideration, as opposed to whether you'll need to shift once more during a rare 1/4 mile run. Having switched to 4.10s and being surprised with how mild the change actually was, I personally would never consider spending that much money to go with LESS than 4.10s...3.90s just aren't enough of a change to drop that much coin, IMHO. In fact, knowing what I know now, I would have put 4.56s in mine. Just my 2 cents on gears; I'm sure I've pulled the string and the floodgates will now open...

[mgg]

I am always amazed at the response to 4:10 gear ratios. The negative remarks surrounding these gears is almost comical. From a dead stop and launch it is more difficult to not have tire spin but I hate to tell you guys independent rear ends are not made for drag racing. Just in case you didn't know ZR-1s are not drag cars. I didn't say it isn't fun but the car was never designed as a drag racer otherwise it would have a solid rear axle like a mustang! How often does your car spend time at the drag strip or launching from a dead stop really hard. My car is a Haibeck 510 package that has 4:10s. From a five mph roll in first gear the car hooks great and rockets out of the gate. Exiting a corner and getting on the gas the car can be right in its powerband and accelerates , pulls and hooks tremendously. The coilovers and Rippie brackets help hook up out of the corner but coming out of a third gear corner at 4 grand and having 7300 rpm to play with the 4:10s prove how valuable they are. I raced c4 corvettes in scca and nasa for over 15 years at race tracks from Watkins Glen to Summit Point and VIR and to hear these conversations regarding the disadvantage these gears have is ridiculous! If you are going to drag race buy drag radials and take advantage of the gears! The only scenario that has any validity would be in a mile shootout. 1/2 mile would most likely favor the 4:10s as you would get there more quickly. There is not a right or wrong answer it is want you want our of your car. I can tell you my 4:10s are never coming out! Remember the road racing rule, "he who gets on the gas fist wins" if you can pull harder out a corner and get a jump on the car behind you or beside you " given that brakes are somewhat equal as well as driving skill" it is VERY difficult to get past the car in front. Just my two cents but this conversation always flips my switch.

[KILLSHOTS]

I am always amazed at the response to 4:10 gear ratios. The negative remarks surrounding these gears is almost comical. From a dead stop and launch it is more difficult to not have tire spin but I hate to tell you guys independent rear ends are not made for drag racing. Just in case you didn't know ZR-1s are not drag cars. I didn't say it isn't fun but the car was never designed as a drag racer otherwise it would have a solid rear axle like a mustang! How often does your car spend time at the drag strip or launching from a dead stop really hard. My car is a Haibeck 510 package that has 4:10s. From a five mph roll in first gear the car hooks great and rockets out of the gate. Exiting a corner and getting on the gas the car can be right in its powerband and accelerates , pulls and hooks tremendously. The coilovers and Rippie brackets help hook up out of the corner but coming out of a third gear corner at 4 grand and having 7300 rpm to play with the 4:10s prove how valuable they are. I raced c4 corvettes in scca and nasa for over 15 years at race tracks from Watkins Glen to Summit Point and VIR and to hear these conversations regarding the disadvantage these gears have is ridiculous! If you are going to drag race buy drag radials and take advantage of the gears! The only scenario that has any validity would be in a mile shootout. 1/2 mile would most likely favor the 4:10s as you would get there more quickly. There is not a right or wrong answer it is want you want our of your car. I can tell you my 4:10s are never coming out! Remember the road racing rule, "he who gets on the gas fist wins" if you can pull harder out a corner and get a jump on the car behind you or beside you " given that brakes are somewhat equal as well as driving skill" it is VERY difficult to get past the car in front. Just my two cents but this conversation always flips my switch.
I'm with you. Anytime anybody mentions gears, suddenly all that matters is shift points and trap speeds. It's great to know that our cars are capable of quick 1/4 mile times, but whose ZR-1 spends more than just an occasional Saturday afternoon on a dragstrip?

It's a bit like choosing a lifted Jeep as my daily driver to use in outside sales, but running around telling everyone how great it was in the mud, that ONE time I took it offroad. Really? Does that really matter? Wouldn't I have been better off choosing a more practical vehicle to drive on-road, since that's where it spends 99.9% of its time? Same situation as choosing gears for the 1/4 mile, in my mind. Again, JMHO.

[Bob Eyres]

The very fact that owners who run stock gears, or anything under 4.10's are running the quarter with a three speed proves my point. With a three speed you are sacrificing flexibility, and performance.
I learned that with my first small block chevy in 1965. My 57' hardtop was quicker, and more fun to drive with a four speed. Gas was cheap, and after popping 4.56's in the rear....yeeehaw, I had a real street machine.
Then in 1970, I built my first Corvette, a split window solid lifter 340hp/327 with 4.56's and low profile rubber. Once again amazed, that little car just squatted and launched, holding off my buddies L88 powered GTO for a block (before he hooked up :eek:).
To me the ZR-1 is a reincarnation of that car, a high winding screamer that will stay with anything on the road.
I'm obviously a believer in short gears, especially with our 7,200rpm LT5. Let the bitch sing,..... please.
And we have the luxury of TWO more gears after fourth, fifth for high speed work, and sixth for mileage. What could be better?

With 4.10 gears, a ZR-1 in sixth gear theoretically tops out around 270mph. Does anyone think that isn't enough?

[Fully Vetted]

The bottom line to me is you can only choose one gear. You have to figure out what your goal is and what sacrifices you're willing to make. Personally, I don't track my car. But, the stock gears are dogs on the street and I was tired of having to be just in the right gear all the time. The 3.90's still allow me to use first gear effectively while cruising while at the same time giving 3rd and 4th gear a ton more punch. I'm not saying 4.10's don't do the same but I have closed 80% of the gap between stock and 4.10's and I haven't given up anything. If you've done the mods and can pull a little taller gear I would say go with 3.90's or even 3.73's. I've always gone with the rule that for street cars the more power you have the taller gear you can pull.

BTW - there are plenty of threads about this very subject on this site and they all end the same. People have different uses for their Z and every one of them require a different gear set up.

[XfireZ51]

Bob,

You should speak w Pete. He ran 4.10s and went back to 3.45s. His 1/4 times and traps were nearly the same either way.

[Bob Eyres]

Pete's car is the strongest 350 stock block car I've ever seen. It's banging on the tens, even with a stock gear in the rear. But compare it to another legendary ZR-1, the white 415 built for SW by John Lingenfelter (now owned by WydGlydJim). This car has at least 100hp. more than Pete's, same IRS rear end but in this shot it is running 4.10 gears and does the quarter using all four gears.

http://www.youtube.com/watch?v=3ZrNvJxDD-

http://www.youtube.com/watch?v=SFNFOhGGlR4

I'm just saying that white car launches so well because of the gears and tires. And that the 675+hp 415 doesn't overpower it.
Just a guess, but I think that setup in Pete's car would get it deep into the tens.:dancing JMHO.

[Hog]

4.10's are good for 130mph in 4th. I'm sure David's ZR-1 is fast in the 1/4 but it isn't that fast.(unless he's running a 250 shot) ;)

I must have misunderstood what he was stating. I took it as he had to **** to 5th gear to get through the 1/4 mile.

[Fully Vetted]

My understanding from other ZR-1 owners with 4.10's was that they had to shift into 5th to finish the 1/4 mile. I don't have 4.10's so I don't know that to be true. But that is what I've heard.

[Bob Eyres]

My understanding from other ZR-1 owners with 4.10's was that they had to shift into 5th to finish the 1/4 mile. I don't have 4.10's so I don't know that to be true. But that is what I've heard.

Dave- I can assure you, that's not the case.
4.10's at 7,000 are at 130+, and at 7,500 are at 140+. That means that unless you have 550+ hp. or more you are not even using the full range of rpm that the 4.10's allow at the strip.
With a stock motor and 4.10's I usually go through the traps at 6.300 to 6.500rpm., well under the redline.

That means that 4.10's are still a "compromise" gear for the quarter mile. There is debate over whether 4.30's, or 4.56's are the ideal gear at the drag strip if you want to use all four gears.

[mgg]

One thing that has now been mentioned is how much nicer it is cruising in 6th gear with the 4:10s. A stock L98 in 6th has a bit of a low end advantage torque was which Gm found acceptable, even with 3:33 gears in 1990. Having bought one of these cars new it was marginally acceptable to be in 6th at 60mph. With only 4700 rpm to play with I understand it. However, a ZR-1 in 6th with 3:45s is just a frickn dog at legal highway speeds. NOt that 4:10s turn it into a torque monster by any stretch but it is much more pleasurable to drive and doesn't seem strained at all. With the rpm these cars have to play with it really seems to me to be a great gear for the street. I was actually schocked when I first drove my car after I installed the 4:10s as to how well they worked. I was really worried it might be too much but it is not even close. I could not be happier. As we have all discussed everyone uses his or her car differently, my best suggestion to anyone who is even considering the change to 4:10s or any gear for that matter is find a car with that gear ratio and go for a ride and drive. You will then have all the facts for yourself if it is in fact right for your needs.

[Kevin]

I'm not sure the l98 actually has a low end advantage in torque. I know if feels that way but I"m not sure if it's true

[KILLSHOTS]

One thing that has now been mentioned is how much nicer it is cruising in 6th gear with the 4:10s. A stock L98 in 6th has a bit of a low end advantage torque was which Gm found acceptable, even with 3:33 gears in 1990. Having bought one of these cars new it was marginally acceptable to be in 6th at 60mph. With only 4700 rpm to play with I understand it. However, a ZR-1 in 6th with 3:45s is just a frickn dog at legal highway speeds. NOt that 4:10s turn it into a torque monster by any stretch but it is much more pleasurable to drive and doesn't seem strained at all. With the rpm these cars have to play with it really seems to me to be a great gear for the street. I was actually schocked when I first drove my car after I installed the 4:10s as to how well they worked. I was really worried it might be too much but it is not even close. I could not be happier. As we have all discussed everyone uses his or her car differently, my best suggestion to anyone who is even considering the change to 4:10s or any gear for that matter is find a car with that gear ratio and go for a ride and drive. You will then have all the facts for yourself if it is in fact right for your needs.
This sounds too reasonable to me. I would plead with everyone: PLEASE make absolutely sure that you fully understand EXACTLY how many miles per hour your car will be going in 4th gear as you pass through the 1/4 mile trap. It is absolutely paramount that you have this worked out to within 1/27 of 1 MPH. Otherwise, don't even consider a gear change; the ONLY consideration should be altering shift points and speed on a drag strip.

[Vette73]

I am a new member and see a lot of members
With this set up,actually,a large percentage..

Back in the day if you had 4:11 gears you were always in the right
Lane on the highway......Since there are practically no ZR1s where I
Reside (Bk Ny or anywhere close) I'm going to have to
Take the word of the members....

Maybe to play it safe down the line 390s? .Undestand,I really
Won't be doing any consistent excessive speed on the
Highways,so gears wouldn't be a bad idea...Just,which size .

( 91 blk/blk ZR1 # 428)
(73 Stingray Convertible)

[KILLSHOTS]

I am a new member and see a lot of members
With this set up,actually,a large percentage..

Back in the day if you had 4:11 gears you were always in the right
Lane on the highway......Since there are practically no ZR1s where I
Reside (Bk Ny or anywhere close) I'm going to have to
Take the word of the members....

Maybe to play it safe down the line 390s? .Undestand,I really
Won't be doing any consistent excessive speed on the
Highways,so gears wouldn't be a bad idea...Just,which size .

( 91 blk/blk ZR1 # 428)
(73 Stingray Convertible)
If you want to "play it safe", my advice would be to keep your stock gears AND your money. It's an expensive mod and if you're going to spend that much money, get some bang for your buck and go to at least 4.10s. I'd go to 4.30s or 4.56s if I could do it over again, because I want my car to accelerate hard and I could not care less about all this shift point nonsense. Just the humble opinion of a guy who already paid to have this done.

[edram454]

One thing that has now been mentioned is how much nicer it is cruising in 6th gear with the 4:10s. A stock L98 in 6th has a bit of a low end advantage torque was which Gm found acceptable, even with 3:33 gears in 1990. Having bought one of these cars new it was marginally acceptable to be in 6th at 60mph. With only 4700 rpm to play with I understand it. However, a ZR-1 in 6th with 3:45s is just a frickn dog at legal highway speeds. NOt that 4:10s turn it into a torque monster by any stretch but it is much more pleasurable to drive and doesn't seem strained at all. With the rpm these cars have to play with it really seems to me to be a great gear for the street. I was actually schocked when I first drove my car after I installed the 4:10s as to how well they worked. I was really worried it might be too much but it is not even close. I could not be happier. As we have all discussed everyone uses his or her car differently, my best suggestion to anyone who is even considering the change to 4:10s or any gear for that matter is find a car with that gear ratio and go for a ride and drive. You will then have all the facts for yourself if it is in fact right for your needs.



A zr1 in 6 gear should be a dog. It is a cruising gas mileage gear. When I want to get high gas mileage I put it in 6th gear and watch my rpms drop and my gas mileage climb. Love it that way.

ed ramos #3028

[Kevin]

I am a new member and see a lot of members
With this set up,actually,a large percentage..

Back in the day if you had 4:11 gears you were always in the right
Lane on the highway......Since there are practically no ZR1s where I
Reside (Bk Ny or anywhere close) I'm going to have to
Take the word of the members....

Maybe to play it safe down the line 390s? .Undestand,I really
Won't be doing any consistent excessive speed on the
Highways,so gears wouldn't be a bad idea...Just,which size .

( 91 blk/blk ZR1 # 428)
(73 Stingray Convertible)

if you're doing gear go 4.10 or don't bother. I ran with a lightly modded 93, I think he had headers and exhaust to my chip, who would pull away from me easily but slowly. I'd claw back a few feet during his shift and then he'd keep pulling me.

I think kurt or dwights car was still a 368 at the time so I didn't feel super bad about it considering they could have put miles on the two of us