Engine refresh & slight power increase
Here's what I know about ls1 motors:
1) They run on gasoline.
Now, I was going to take off the intake and heads to start, inspect to make sure everything looks good, look at lifters for uneven wear, push rods, pistons, rings, cam lobes. Then put it back together with new gaskets and new head bolts.
Should I get strengthened head bolts, or are the stock ones fine?
If there is a bad lifter, should I replace all 16 and the cam, and if I replace the lifters, do I use LS7 lifters?
Should I have the heads milled before putting them back on, even if they appear to be in good shape?
I'd like to increase the power just a bit to around 400lbs of torque at the crank, because that's where my drive train's breaking point is. Can I do this with just a cam? If so what cam, and where can I buy it?
I wish to get rid of the egr system, is there a kit for this? Where is the egr physically located?
Where is a good place to buy ls1 parts, such as accessory mounts, belt driven accessories, etc?
Thanks much.
Second, since you'll have the motor apart, replace all the wearable items such as, lifters, stock trunnion rockers (not wearable but they are known to have the needle bearings to come out and wreak havoc into your motor), timing chain, oil pump(new O-ring), better intake manifold (LS6 intake)- will get rid of your EGR as well.
Depends on your budget you can put a better aftermarket cam, replace the heads with either "worked" 241s either or 243s, stock or modded heads and then get a set of stronger pushrods in place of the stockers.
400lb tq at the motor is easy with minor bolt ons.
The stock replacement head bolts are fine, but are a bit annoying to install. You have to use a torque then an angle to properly tighten them. If you can afford to spend a bit more then go for the ARP bolts. They can be reused and if the heads have to come off again in the future they will save you money. Also if you don't have access to an angle meter and have to buy one you will spend close to what the ARP's cost versus the stockers plus the angle meter.
It is possible to reach your power goal with only a cam swap. It would be easier if you upgraded the heads to a newer design. The 241 casting is marginally better and can be picked up pretty cheap. A 243/799 casting can be picked up for 3-400 bucks and are a good for 15-20 HP over a stock LS1 head. Milling to bring the compression up would be a good idea regardless what head you go back with.
There are several sponsors here that sell camshaft kits that include the cam, valve springs, and pushrods. Some of the more common are Texas Speed, Futral Motorsports, Thunder Racing, and EPS. These vendors also carry the gaskets and headbolts that you are going to need to put your engine back together.
The EGR valve bolts to the passenger side head and has a tube that runs up from the exhaust manifold and then to the top/front of the intake(right behind the throttle). I don't know that anyone makes a kit to delete the EGR but all you really need is a block off plate for the exhaust manifold and a rubber expanding freeze plug for the intake.
Accessories are probably best sourced from a junk yard. There are a few places that sell new serpentine setups but they aren't cheap. What accessories you use depends highly on what you plan to install the engine in and the space available in the engine bay.
You don't have to mill the heads, but definitely have them decked to make sure they are smooth and seal well against the block.
Then on the bolts you will need new stock ones at least since the original head bolts are torque to yield and can only be used once. A new set will run about 50 bucks for both heads. The stock ones will be fine but for whatever reason if you needed to pull the heads again arps would be worth it seeing as they are around 100 bucks.
98's tend to have a couple little "quirks" to them so I'd also put these on the list. If you plan on getting any cam the rod bolts start to become a question above 6500 rpm in 98-00 motors katech sells upgraded rod bolts that are 200 a set. arp also makes some that are 89 a set. However the katechs are a direct bolt in and go while the arp's require you to have the rod bores line honed to ensure roundness with the new bolt... katech gets my vote there. also the oil pumps in the 98-00 were known to go out from time to time so an ls6 or ported ls6 pump would be a good idea as well as an ls2 timing chain.
as said above heads would be a nice upgrade for you, the 98 is an oddball yeard seeing as it was the only year for the fbody ls1 to get valve covers and heads with perimeter bolts on the valve cover . 99-up has different valve covers, coil brackets, and heads. A set of 241 heads (stock heads 01-02) that have been ported or a set of 243 heads (stock on ls2/ls6) would be a great choice for a mile cam build. a set of worked over 243's and a nice cam should easily put you in the neighborhood of 440-450hp through an m6 at the tires.
400 ft lbs of torque is easily attainable at the crank by just small bolt ons but a healthy cam will push the numbers way past that.if you want to stay very mild something in the low 220's is a good choice on duration. however for a daily driver that still drives awesome and has a punch something in the 228-234 range is easily doable with a good tune. either way with whatever cam you choose you will also need to measure for new pushrods seeing as the cam lobe will change the length required.
I already have a small fortune invested and still have quite a bit to buy, so I'm trying to keep things semi-reasonable. I appreciate the info, can anyone recommend a good reputable seller to pick up things like the head bolts?




