General LSX Automobile Discussion - Contemplating H/C/I/E on a 100k LS1 & Trans

Hey guys,
I figured I'd post up to see what you guys would do in my situation. I have a 99 Z/28 A4 with about 97,000 miles on it. I've had it since 2005 when it had 62,000 miles on it. Its all original and I've added SLP LMII, Strano/Koni suspension, B&M tranny cooler at 77k, and minor brake upgrades. I have been getting tired of the car as it sits, and I don't want to sell it for nothing since its still a good car. I have been doing basic research on building up the motor, but with nearly 100k on it, would you? It runs like a champ and shows no signs of quitting (**knock on wood). I'd like to get Texas Speed's PRC Stage 2.5 5.3 heads and perhaps the MS3 cam, and of course the supporting mods to go with it as well as HP Tuners. Whats your opinion on my situation?

Go for it! as long as the cars been taking care of there shouldnt be any issues....i'd recommend replacing the timing chain, oil pump, lifters, lifter trays, pushrods etc though

With the significant increase in power you'll see from these modifications, and the fact that the cam you want will require much higher shift points than what a stock 4L60E was desiged for, and the fact it already has 100k on it, I would be prepared for a performance rebuild on the trans. It may not happen right away, but it's something you should be ready for finanically if you want to do this build.

I wouldn't worry about the engine though, if it's been well maintained then it should be fine.

Just remember that a MS3 cam is going to require a different stall convertor.

Thanks for the advice guys. I am also aware that I'll need to replace the seals, pushrods, springs, oil pump, timing chain, and anything else that I'll come in contact with during the swap. Without a doubt I know the rear and trans will need to be done at some point, but I figure that I'll do it in phases. I know alot of guys would rather build the trans and rear first, but I'm anxious to get that nice lopey idle and make this car unique. I want to upgrade the following as I progress:

- PRC Stage 2.5 Heads & MS3 Cam
- All supporting hardware for cam & head swap (rods, springs, gaskets, timing chain, oil pump, injectors)
-Stall converter
-American racing headers and catted y pipe
-Fast Intake with Nick Williams TB
-Strange 12 Bolt with Posi and 3.73's
-Upgrade to ARH rod bolts
-HP Tuners
-New set of rims & tires

I wouldn't worry about the rear too much with an A4 car. This is a much bigger concern for the M6 guys. You'll find tons of us that have done consistant 1.6 or faster 60-foots on the stock 10 bolt with an auto trans. If you can keep wheel hop away, you'll get a long life from the stock rear even with a big stall and more power than stock.

Your trans will likely need to be rebuilt long before you'd ever break the rear.

Go for it. Iam going to be doing a cam real soon just ordered all my parts. I have 143k on mine had it from 50k so I know it's service history.

OP, can i ask why u chose the stage 2.5 5.3 heads? I've been trying to research as I am looking to do h/c as well... but i read all u really get with the stage 2.5 is bigger valves which bearly add any HP for their cost... and i seem to be sold for the LS6 heads and not the 5.3.... better flow from what I read?


But as it pertains to your question. I notice you dont really have any other mods. I dont know how much money you have, but ur last post lists almost $10,000 in parts alone... you got that cash to throw at it at once? I just think ur shooting way too far ahead here. Do the headers and exhaust first if you ask me.

Udie, I saw the stage 2.5s 5.3s and they seemed like the best bang for the buck. I'm not opposed to looking at other options, but I seemed to settle on those heads if I was going to do it. I am aware that this build will cost roughly $10,000. I figure to lessen the sticker shock I'd just do it in pieces. I know that there is some risk associated with that, but I'm just exploring my options right now. My car is really boring at this point and I'd like to either build it or sell it.

Udie, I saw the stage 2.5s 5.3s and they seemed like the best bang for the buck. I'm not opposed to looking at other options, but I seemed to settle on those heads if I was going to do it. I am aware that this build will cost roughly $10,000. I figure to lessen the sticker shock I'd just do it in pieces. I know that there is some risk associated with that, but I'm just exploring my options right now. My car is really boring at this point and I'd like to either build it or sell it.

The stage 1 LS6 heads are cheaper. Anyway, right... doing it in pieces is what im talking about. This thread you're asking about h/c, but I think you should be asking about exhaust. Start with that, get yourself a full exhaust.

After that... get a stall... 3600 or so... that will really transform your car. I highly recommend a stall. My point is you got a while before you should be thinking h/c.

before you go ahead and do h/c ect. your gunna need to do other things first like headers and a converter like everyone has said or you will dump all this time and money into your car and its gunna drive like shit.

So you are going to be doing this and still running the stock intake.

i did my h/c swap at 100k also. I have 143k on it now and after 3 years it has been good to me. Still on the stock trans and rear and have been 1.67 in the 60'