Nacho_ZR1

Screw my kiddos....This year, daddy comes first

Jeals - New 02 sensors and hi-temp painted


4.30's

solid dobe

ßill

The headers look cool. Are you sure about the 4.30s? I've got 4.10s in mine withe stock size tires and 1st gear is just about useless. If I was to change I would be looking at ≈ 3.80s. On the good side with 4.10s 6th gear is good below 50 MPH.
Enjoy!

xlr8nflorida

You need better tires, Nitto 555R and 1st gear won't be useless

I wouldn't do more then 410s though.

ZRWHAT

Nacho,

Do yourself a favor and have the headers Ceramic Coated, paint won't last a week once you really run the car like it was made to be ran.

Increadible difference in the underhood temps with coated headers, not to mention the headers will last a long, long time once ceramic coated, if you leave them painted, figure on painting them several times a season and if you don't, they will eventually deteriorate.

Good luck and I agree with Bill on the 4:30 gears, the multiplication of HP in your lower gears will be waaay too much with that gearset if you run anything other then a drag radial at all times, even on the street!

Gibby

xlr8nflorida

I agree 100% but didn't want to say it.


Even if you are on a bare minimum budget, at least coat the driver side which is what you will see, the passenger side you hardly see at it.




Actually do both, its only 300-400 bucks.

Goldcylon

Well now we know who bought them. Great price on those headers!! Another vote for ceramic coating I also have that other piece you are missing somewhere in the garage

Nacho_ZR1

Do you have a link or a contact person for the ceramic coating?

Goldcylon

Nacho. Pic sent of the right side or "passenger side" adaptor you are missing . GC

Paul Workman

If I may ask,

Have you done any quarter mile times? If so, couldja tell me what the rpm was when you finished and what is your RWHP?

Many thanks in advance.

To Nacho, I like the black headers. Hope you get all the gremlins chased away from your Z. Once all the gremlins are run to ground and old cracked stuff is replaced, it is just amazing what these cars will do! You're in good hands, looks like.

P.

VetteMed

IF Nacho doesn't want that passenger adapter, I'll take it, GC.

xlr8nflorida

Jet hot coating


http://www.mydigitalpublication.com/...=22398&p=1#_m0

ZRWHAT

Nacho,

Here are my Watsons with ceramic coating in Sterling.

Gibby

[IMG][/IMG]

Demps

I have 4.10s and 4.30s in cars. The 4.10 car is now a 415 and haven't run it. When it was a 350 it trapped 119.95 in Boise in fourth at what I remember to be around 7,000rpms.

The 4.30 car is another story--don't like the gears. The car is an SGC 350 with stage I cams. It looses some umph around 6,300rpms so the gears hurt it (bought it that way). I would do 3.73s in both cars if I were starting from scratch and 3.91s or 4.10s in a stock-ish car. The 4.30 car trapped 118 in fourth at BG (on very bad injectors) and it was spinning around 7,200rpms.

I don't have an rpm/gear calcuator for exact numbers but that is what I remember.

Ted

Okay, so my memory is not that good. Here is a site for calculating:
http://www.angelfire.com/fl/procrastination/rear.html

315 35 17 tire should have a 25.68 diameter. Fourth gear is 1.00:1.
4.10s trapping 120mph should be 6440rpms
4.30s trapping 120mph should be 6755rpms

A26B

+1 on Jet-Hot.
http://www.jet-hot.com/

Graybeard ZR1

This opinion is common on this board, but I don't understand it. By my calculations a car with stock tire size and 4.09 - 4.10 gears, at a 7K redline, is trapping over 130 mph in the quarter mile at the top of fourth. This is faster than any stock or mildly modified ZR-1 can actually go in the Qtr., so what's the problem?
In selecting the gears for my car, I wanted to peak in fourth gear in the qtr. and have 5th and sixth for cruising and mileage. 4.10's, like I have are actually not high enough by this criteria. 4.30's, or even 4.56's might do better.
First gear with 4.09, or 4.10's gets almost to 50mph., and what's wrong with cruising over 75 mph. at 2K rpm in 6th gear.(4.10's)

The car gets loose in first?...That's a Tire, or Driver problem, not a too low gearset.

Just MHO

locobob

It's probably not your memory Ted, most Z tachs run a bit fast. Mine is about 500rpm over at 7K.
The 4.30's would be good for a modified car trapping in the low to mid 120's but you'd have to run drag tires to hook first. For a lightly modded car with street tires I'd go with 3.54 - 121mph at 7200rpm in third.

locobob

I had 4.09's on my 368 for quite a while. It would blow away the tires in first at any speed. Once the tires got old it would spin them in second at 40mph as well - sure looked cool but not the quickest way down the track. I think it's important to be honest with yourself about what you want out of the car and to look at the drive-train as a whole (including tires). Not everyone is willing or can run drag radials year round. In the quarter 4.10's are not very efficient for a stock or lightly modded car - you end up shifting to 4th and only using half the gear.

ßill

That is my experience Bob. I'm not much of a drag racer and my 60' times prove it. My car had 4.10s when I bought it and like you said ran out of 3rd around 200' short of the lights.

Graybeard, My tach is showing abt 2400 rpm at 75 mph and giving 24-25 mpg in 6th.

Graybeard ZR1

IMHO running the quarter in three gears is "not very efficient". I've felt that way since I put a four speed in my 57' Chevy forty five years ago.
With a six speed I've got four acceleration gears, and two more gears for cruising and mileage. Best of both worlds.

Best- 91' ZR-1 - 12.06@117 mph. 1.76 60ft. (Stock motor,bolt-ons only) @24 mpg.hwy.