I'm a long time forum member who usually hangs out in the C3 area, but I came across a deal on a C4 that I just couldn't resist, so they're now a nice polo green 93 in my garage. :) I gotta tell you guys, this car is WAY more fun to drive than I thought it would be. I had driven an earlier C4 in the past and wasn't really into it, but it was somebody else's car so I couldn't drive it the way I wanted to. These cars really keep their composure when pushed hard, much more control than the modified C3s that I'm used to.

The LT1/ZF 6-speed combo is great, but I'd really like a little more power. Where to start? I tried the forum search, but it's pretty useless right now. What type of rear wheel numbers can you get out of one of these motors with head/cam/intake work and a stock bottom end? Is 350-400 rwhp a stretch while maintaining decent drivability and good traffic manners? I think that's the general range that I'll be looking for, even if it requires short block work to get more cubes. I'm not really interested in nitrous or forced induction (at least not yet :D)

Thanks all! I'm looking forward to a long and happy history with this car.


[Modified by Flareside, 9:41 PM 2/2/2004]

 

Welcome to the life of an LT1 owner, you'll never go back.

First mods, do the free stuff, open-lid (just cut the metal plate in front of the filter and throw a K&N in), tb bypass, simply re-route the coolant from the throttle body straight into the radiator. There are a few other free things as well I'm sure.

LT1s love gears, get some new gears, you'll already have a Dana 44 so just throw some 4.10s in there or 3.92s. LT1s sound great with exhaust as well, much better than LS1s in my opinion, get a nice cat-back or just do some muffler elims. 350rwhp is easy in an LT1, hell you start out with what? like 255 or so in a well maintained M6. With the mods I have @ 135,000 miles I dynoed at 265 to the wheels and I have only a couple bolt ons, plus I'm automatic so more drivetrian loss. Heads and cam would easily get you 350 to the wheels with good tuning. You could always get the hot cam kit as well. Like $510 from Summit and includes rockers, cam, springs, shims, and something else I believe, lots of people love the cam, but it's not EXTREMELY powerful or anything. Suspension on these cars is already good, but stiffen it up some and you'll be amazed as well. Really just depends on what you want and how much you want to spend. Knowing how much money you want to fork out will probably get you abotu 100 responses that have parts that fit directly into your budget.

:cheers:

 

Gears, head porting, LT4 Hotcam and 1.6RR youll get that 350rwhp.

I know Nathan Plemons had LT4 hotcam, 1.7rr, ported heads, and was putting out 370-something rw.

So if you want more, pick a slightly bigger cam.

Realize that any cam change also requires a computer reprogram.

 

:iagree: And you might as well throw in a set of long tubes to fully utilize all the increased breathing.

 

a lot of his mods are gonna be limited by emission regs... and long tubes won't fly in NJ...

I would look at a cat-back system, I recommend Corsa.

To improve the overall driving experience, I would suggest an aftermarket shifter. The Hurst is what I have, and is a nice part... the B&M is popular with drag racers - very positive and direct shift. The Hurst is more sublime.

Either way, you will shorten the throw.

Beam Plates. You will hear about them around here. They go on the c-beam that joins the tranny to the rear differential. The beam plate is a mounting plate for the bolts. They help to distribute torque better. I have them, what I have noticed is a reduction in the rear wheel kick to the right under hard acceloration.

Finally, brakes... The C4 brakes are ok, but you might want to look at upgrading to 13" rotors... unless you already have the J55 option.

RPO's are under the center console lid.

The factory stereo is junk, too... the CD player will quit and so will the speakers... ick...

you might want to consider improving the ignition. http://www.bailey-eng.com/ltcc.html

Great product.

Great choice in colours! Mine is a 92 - Polo Green/Tan! And a 6spd!
:cheers:

Welcome to the C4's! :seeya


[Modified by bogus, 10:58 PM 2/2/2004]

 

[QUOTE]a lot of his mods are gonna be limited by emission regs... and long tubes won't fly in NJ... [QUOTE]

Bummer, ain't it great to live in a free country? Damn shrub-huggers.......

 

:withstupid:

 

Ironically I am from Austin, home to 123490283409823409823409832 tree-huggers, yet we have no emission control other than visual. I'm quite suprised every time I go get an inspection.

 

Yea, but if I remember correctly from when I lived in Texas (admittedly over 20 years ago) everyone is issued a pickup-truck rifle rack in school. ;) If I were a mechanic I wouldn't want to go pokin' 'round another man's compartment when everybody's armed. :flag

 

:withstupid: I live in California guys need I say more? :cry then :cuss

I don't have that many mods and I'm doing ok HP wise. But I agree with the others as far as mods. Good luck :thumbs:


[Modified by WickedC4, 9:20 PM 2/2/2004]

 

Great info, thanks all!

I've already ordered a set of beam plates, and bought a Corsa exhaust from another forum member, so those items are covered. Looks like I'll be shopping for a shifter as well.

Who have you guys used for head porting, and how much should I expect to spend there? Should the intake be ported at the same time?

How's the drivability of the LT4 hotcam? The stock LT1 cam is way too smooth for me, but I don't want to make the car a handful in traffic either. Can the hotcam equipped motor idle for long periods without loading up and cruise on the highway in OD?

Thanks again.

 

ALot of people like the B+M Ripper. Its the shortest throw out of all the aftermarket shifters. THe other choice is the Hurst which is sorta medium compaired to the B+M. So its your call there.
You could get shorties which isn't as good as LTs but not too bad either. I would get some used here b/c I see em pop up sometimes.

Oh most important I would Vent your optispark. :smash:

 

Can you retain the reverse lockout with the B&M?

 

no. none of the aftermarket's retain the lockout... and GM ditched it in 1994, anyway.

Don't worry... the lockout is not an issue.

You may or may not like the B&M for daily use. I would suggest finding forum members who have one and testing it out.

 

No one mentioned GEARS.... think about 4.10 to go with that 6 speed. at 60 mph you will still be turning about 2200 rpm in 6th gear..& it will WAKE the car UP!