I recently picked up my second LT1 Z28. My first, I had way back in high school... and at the time I felt pretty badass with a drop-in k&n panel filter and flowmaster muffler welded in to the stock exhaust. It's been a long time since then, and with my recent second Z28... I'd like to approach things right. I've learned quite a bit when it comes to Mustangs, as I've owned a couple of those between my two Camaros... But the Camaro is a different beast so I'm clearing my mind and starting from scratch.

So, what are some good basic bolt-ons? Mainly looking to free up some power while maintaining good drivability, as the car will be a daily driver. How much power can safely be made before needing a tune? Are these things hard to tune?

Currently, it has a K&N intake, 1LE intake elbow, coolant bypassed throttle body, and SS catback.

Also, any widely known problems to look out for? I know heat was a big deal with my last Z28, as it overheated a few times in the summer. But I also drove that car harder than I should have most of the time.

 

Welcome to LS1tech!

As you've already learned, cooling is a big thing with these cars. You can never have enough.

A tune will always help your car run better.

Most of the bolt on mods will help in small increments-you won't feel much with them.

The best gains from a bolt on is long tube headers and an exhaust system.

 

1-3\4 headers, Lloyd Elliot of AI top end.

 

Stall if auto....

 

As mentioned already, headers (I'd get ceramic coated to reduce engine compartment temps, better longevity, and looks) are the best gain for the money bolt on wise, then I'd get a 160 thermostat and a PCM tuned to match the thermostat and your mods, it should not be overheating in the summer. Maybe consider an electric WP, they flow better at low RPM and idling in traffic, not really at higher RPM's though, also free up 5-10 hp. LT1's are definitely more sensitive to heat soak especially in the summer and you will feel the power loss more noticeably than say a LS1 or even a mustang with their plastic/composite intakes. Gears are a nice mod for the money although not "bolt ons", boxed/tubular control arms are also a must if you don't want axle hop and fairly cheap/easy to install.

 

Definitely address everything on the exhaust side! Can't go wrong with some longtubes.

If it's an automatic, consider an external trans cooler and converter!

 

Thank you. How accurate is the stock temp gauge? Is an aftermarket water temp gauge a worthwhile investment?

Sadly, I live in California... I don't know if LT1s have any street legal long tubes options. I know Mustangs don't... As their stock mid pipe has four cats, and long tubes remove two, and move the remaining two down stream... Which is illegal here.

Are shorties/mid length headers worth the money? I'd imagine there must be some CARB legal shorties or mids with the cat being in the y-pipe.

Is drilling the 160° thermostat advisable? With my Mustangs, I always drilled a small hole in them 1) to allow a minute coolant flow, and 2) allow air bubbles to escape.

It is a 6-speed manual

I loved my auto back in high school for drag racing. But I wanted a manual this go round.

 

There are no long tubes which are CARB legal since they all technically change the stock location of the cats, get Pacesetter mid-tubes, better than shorties but 50 state legal, I have them for ground clearance reasons.

I see no real reason to drill a 160 thermostat, unless you live in the desert or something....it would just take longer to warm up in winter. If you get the fans tuned to come on early and just put in the 160 stat, you should have no cooling issues assuming the WP is working properly.

Oh yeah, get an aftermarket shifter ASAP! The stock one is a POS.

 

Just curious what shifter kits?

 

Wow...there's LT1 cars in Russia!? That's got to be about as common as a Trabant or a good running Yugo in the US Hurst makes a good shifter, makes the 2-3 shift MUCH easier as it's self centering, and shorter throws, there's also good reviews for the MGW shifter for these cars:https://ls1tech.com/forums/lt1-lt4-m...w-shifter.html

 

OP

On a stock car the basics are CAI & exhaust. Sounds like you have those already.

Any CARB shorty will be better than stock, unfortunately not as much as mid/long tubes but I understand the Calif. deal.

other basic steps:

better valve springs and 1:6 RR
PCM tune
160 stat

 

that was a couple hours ago. he could be in Ukraine by now...

 

Can valve springs and roller rockers be installed at home by an amateur? Or would that be better left to a professional?

Would a TB airfoil and new MAF housing be worth the money?

Also, is the y-pipe easy to swap on and off for smog time every two years? Would an off-road y-pipe be worth running?

 

TB airfoil is worth it IMO, they are $25-30 on ebay, the cheapest bolt on you can buy, the stock MAF is fine, as mentioned already, Pacesetter midtubes are CARB legal even in the **** state of Cali, AND they come included with the y pipe which keeps stock location of the cat/s; there are NO long tube headers which are CARB legal, if you can pay somebody off to look the other way, that's another story entirely, you got a hookup? That is the question... If so, go for the longtubes with a catted y. Cats only cost 5-10hp max, not worth the trouble of taking them off to pass inspection IMHO. You can do 1.6 RR and springs yourself, but require more time/expertise than the "easy" bolt ons, depends on your comfort level, but are worth a good 15+hp. As a plus, you need those anyway if you ever get a cam. Nitrous kit is also good "bolt on" for the money

 

As said earlier, mids and y pipe, EWP is good for dds or drag cars, not so much on road race cars. Valvesprings can be installed at home, I did it for the first time with Tim's Tool, it's easy. The real benefit of valvesprings and rockers is the ability to run up to 6300 rpm with no valve float and no fear about the rocker spinning off the pushrod (if you get NSA rockers). Just shifting at 6300 instead of 5200 drops your 1/4 mile time by .2-.4 seconds even if it only gains about 15hp.
For shifters, it's about feel and what you like. The stock throw is about 10 inches, I have a B&M ripper and the throw is about 7 but I love how it feels. My brother has an mgw and it's only about 4" but I don't like how it feels, too hard to push. The hurst one felt too sloppy. Havnt driven a car with the pro 5.0. You also definitely want a skip shift eliminator, it's basically just a resistor, but eliminates the annoying 1-4 skip shift.
You'll definitely want a mail order tune, after I did headers and hasn't gotten the tune in the mail yet I was pissed because the car didnt feel faster, as soon as I got the tune it got the car running right and I felt the huge difference of all the boltons. Full boltons and a tune and shifting at 6300 will get you 12s if you can powershift.

 

Thanks for all the advice and suggestions! I'm glad these older cars still have a strong following and aftermarket. I feared everyone moved on to the Ls1 and left these cars behind. TB airfoil is definitely on the list now. CARB legal headers as well.

RR and valve springs sound awesome. Is a 6k rpm shift point completely safe once the valve train is beefed up? The bottom end is fine spinning that high?

The ECU already has the cooling fans turning on at a lower temp. Previous owner said 190 I think? I'll end up adding a 160° thermostat as well... But I'm on the fence regarding an electric water pump. The car is primarily a DD and will see twisty driving roads and cruises much more often than the drag strip. What are the pros and cons for the electric water pump versus a factory pump?

The skip shift feature is also already disabled in the tune.

The current shifter feels decent. Not the tightest, but not too sloppy. It centers for 2nd-3rd shift but not as strongly as my last aftermarket shifter... So I really don't know if it's factory or aftermarket.

I forgot how large these cars are. It's definitely a tight fit in the garage compared to my previous Saleen Mustang.

 

Spray it.

 

I run a Pro 5.0 shifter with a UMI short stick. Worth every penny.

I REALLY wish Steeda made their Tri-Ax for these cars. I had a Tri-Ax with MGW's adjustable handle in my old Thunderbird Turbo Coupe and it was my favorite setup EVER.

I have 1.6rr's, hardened pushrods, 7/16's rocker studs and guide plates with LT4 valve springs. Car doesn't have a problem spinning to 6K with 207K miles on it.

 

I would get 4.10s for it if youre not concerned going down a couple numbers in gas mileage. 4.10s, legal full exhaust, and a tune will get you right. I think all that together if you do it yourself should be done for right around $1000.

 

The Air Foil is worth the money! Some people say it is a waste of money. I have a book where they did dyno runs with and without the air foil on a 350.

Mostly stock 350--- 6 horsepower gain at the higher rpms.

Highly modified 350---- 11 horsepower gain in the higher rpms

It made from 1-4 more hp in the lower rpms. This also makes sense because at higher rpms there is more air turbulence and the air foil smooths the flow out.

Don't forget the throttle body bypass to keep that hot coolant away from the throttle body. It's worth at least a few hp. 6 here 3 there it start to add up and make a difference with bolt ons. Hey wait a minute? I still have to do these two mods to my Z28!