New Engine?
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Joined: Sep 2009
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From: Pittsburgh/Butler PA
New Engine?
So I have a 03Z with 111,000 miles on it. Have a very mild cam on car that was installed by previous owner; stock heads. Also have headers, exhaust and Vararam. Got car dyno tuned last summer and got 398rwhp. Car runs great, stalls every so often when AC is on, about it. I was looking to put a Cam/Heads package in it as the harmonic balancer needs to be replaced anyway. I have no idea of the cam thats in it now as I did not put it in. I am being told by local shops that with that many miles they would never open the engine up to do this?? They said It will throw the compression off, and had a few other excuses.
So now do i get a new engine to drop in it? If so what? I dont have a lot of money to put into it so it would have to be cheap. OR do I continue to roll with this one?? What do I do?!
Thanks!
So now do i get a new engine to drop in it? If so what? I dont have a lot of money to put into it so it would have to be cheap. OR do I continue to roll with this one?? What do I do?!
Thanks!
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Evaluate the condition of your engine, and make your decisions from there.
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From: Pittsburgh/Butler PA
25 years ago, I would have agreed with the advice.....not anymore. Provided the engine has been well maintained, passes a compression and leakdown test, does not burn oil, etc...... there is no reason why you can not do a head/cam mod. I'd really like to know, how it's going to "throw the compression off", especially if you stay with the same size combustions chambers....
Evaluate the condition of your engine, and make your decisions from there.
Tech Contributor
Joined: Jan 2007
Posts: 19,398
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From: Dyer, IN
Yea, the car does not go through oil at all, I change it every 3000 miles with synthetic. The car has no issues at all. I was VERY upset when i was being told this. He said about the compression and he also had an excuse about the bearings?? I forget exactly what he said about that...
Do the following, and move forward with confidence:
1) Oil analysis - gives you an idea how much metal is floating around.
2) What is you idle oil pressure, and at WOT?
3) Do a compression test.
4) Do a leak down test.
See what you come up with, and make an educated decision.
Race Director
Joined: Sep 2005
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From: Pasco WA
I think that Lucky's advice is pretty solid, but it's really a good idea to raise your compression when doing a head swap. It's cheap HP, great for TQ, and can even improve your gas mileage. IDK how it's affected by a higher miles motor, though; I've no experience in that area.
Melting Slicks
Joined: Dec 2006
Posts: 2,186
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From: Woodinville WA
The only thing I can think of about changing the compression is the dynamic compression, which a cam with more overlap will lower it which is why it's good to increase the compression ratio (as Zeevette noted) when doing a cam swap.
I think the shop is just afraid to do a cam swap on a high mileage motor, so they are comming up with excusses. They might be afraid if you take it out, beat on it and blow it up, you might try to hold them liable.
I think the shop is just afraid to do a cam swap on a high mileage motor, so they are comming up with excusses. They might be afraid if you take it out, beat on it and blow it up, you might try to hold them liable.
Melting Slicks
Joined: Dec 2006
Posts: 2,186
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From: Woodinville WA
The LS cylinder liners are usually only over-bored .005 inches and a 4.00stroke crank will up the cubes to near 383ci.
Not sure why you are thinking 111k miles is too much to rebuild, unless you are talking about just the cam swap? A rebuild with stock block, crank and rods would be good as new if checked and done properly.
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Thread Starter
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Joined: Sep 2009
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From: Pittsburgh/Butler PA
So I am thinking of installing a set of AFR 205 heads and leaving the cam that is in there, as I dont know what it is. I am guessing from my HP it is around a 224? And I will just go with that set up till the engine goes, whenever that may be. Since I dont want to do FI or anything, I am not sure if it is worth going through the hassle of a new engine?
Le Mans Master
Joined: Nov 2009
Posts: 6,119
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From: Huntington tx
I pulled my heads off and replaced my cam with a TP 228R and lifters at 93,000 miles. The engine internals looked new, everything was great. The only real wear occured at the valve seats and just barely. I lapped the valves, seats, and reinstalled everything and the engine runs fantastic now like it did when I upgraded. Looking for another 100,000 miles.
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Joined: Sep 2009
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From: Pittsburgh/Butler PA
I pulled my heads off and replaced my cam with a TP 228R and lifters at 93,000 miles. The engine internals looked new, everything was great. The only real wear occured at the valve seats and just barely. I lapped the valves, seats, and reinstalled everything and the engine runs fantastic now like it did when I upgraded. Looking for another 100,000 miles.
ALSO how do you like that cam as that is the exact one I was looking into and couldnt find many people with it? How does it drive? What were your power gains? I didnt want to go to a huge cam or anything, this seemed perfect, just want some feedback!
THANKS!
Last edited by Sidieux; Mar 29, 2011 at 12:29 AM.
Race Director
Joined: Sep 2005
Posts: 11,060
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From: Pasco WA
Most people have had greater success with split duration cams, such as 228-232, than single durations. As far as installation, there's a step-by-step guide @ ls1howto.com that works well. I'd change my valvesprings, too. Too many incidences of failure to ignore.
Last edited by zeevette; Mar 29, 2011 at 01:54 AM.
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Joined: Jul 2010
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From: Pittsburgh PA
Listen to Lucky's advice, it is solid.
I wouldn't go back to the shop that gave you that advice. They sound like a bunch of "lamer excuse" idiots.
My advice, take it for what it's worth (and it's free, and we know you get what you pay for, so consider that.........lol):
-a cam swap will NOT change your static compression ratio. The only thing(s) that will change your SCR are installing heads with a different combustion chamber volume or switching to a different thickness head gasket. Other than that you'd have to machine the block/swap pistons to change the SCR.
-Dynamic compression ratio CAN be changed by swapping the cam. Some argue that DCR is overrated anyway. I wouldn't worry about it.
My personal belief is that the heads are AS important, maybe MORE important, for gaining performance/hp, as the cam. If you're going to go to the trouble to swap the heads, put some good heads on there. If you're using 243s, send them out to Advanced Induction or TEA for some porting.
Match your head/cam combo. My personal fav is Ed Curtis (Flowtech Induction; Ed does mean porting, too). Patrick G. will also custom-spec a cam for your application.
Good luck.
I wouldn't go back to the shop that gave you that advice. They sound like a bunch of "lamer excuse" idiots.
My advice, take it for what it's worth (and it's free, and we know you get what you pay for, so consider that.........lol):
-a cam swap will NOT change your static compression ratio. The only thing(s) that will change your SCR are installing heads with a different combustion chamber volume or switching to a different thickness head gasket. Other than that you'd have to machine the block/swap pistons to change the SCR.
-Dynamic compression ratio CAN be changed by swapping the cam. Some argue that DCR is overrated anyway. I wouldn't worry about it.
My personal belief is that the heads are AS important, maybe MORE important, for gaining performance/hp, as the cam. If you're going to go to the trouble to swap the heads, put some good heads on there. If you're using 243s, send them out to Advanced Induction or TEA for some porting.
Match your head/cam combo. My personal fav is Ed Curtis (Flowtech Induction; Ed does mean porting, too). Patrick G. will also custom-spec a cam for your application.
Good luck.
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From: Pittsburgh PA
You can always pull the cam and have it "cam doctored" to find out what the specs are.
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Joined: Sep 2009
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From: Pittsburgh/Butler PA
When you state to match your heads and cam combo, this is what I am trying to do. I see people with lower cams get better results than someone with a bigger cam; probably just because their car is "built" properly. I have decided to do the cam for the fact that since the engine has that many miles, I figure I should do the timing chain and oil pump. I also want to know the cam that is in my car. Since I am doing the cam, I need to do some less expensive heads. I have decided to do the PRC stage 1, or stage 2.5? is it really worth going to the 2.5? Also will these heads transfer to a forged engine if thats what I do down the road in the future?
I have read numerous threads and cannot find a good cam recommendation to go with these heads. I dont want anything big because I dont want to put a lot of stress on the engine. I was thinking maybe the TS 228R??
I have read numerous threads and cannot find a good cam recommendation to go with these heads. I dont want anything big because I dont want to put a lot of stress on the engine. I was thinking maybe the TS 228R??
Last edited by Sidieux; Mar 30, 2011 at 10:32 AM.
Tech Contributor
Joined: Sep 2005
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From: New Market AL
I installed AFR 205 heads and a 224/230° cam in my '99 C5 with 155,000 miles on the odometer. It currently just rolled past 220,000 still with the stock shortblock. The only thing I did to the engine in the past 65,000 miles was to replaced the valvesprings due to the cam's .600" lift.
Quite going to whoever gave you the bad advice to rebuild your LS1 at 111k miles. Stay way from them. Absolutely go with a set of AFR 205s on your 346 - that is the engine they were designed for. Don't think twice about upgrading your LS1 with over 100k miles - and then run it hard without worry.
Now, what are you waiting for?
Quite going to whoever gave you the bad advice to rebuild your LS1 at 111k miles. Stay way from them. Absolutely go with a set of AFR 205s on your 346 - that is the engine they were designed for. Don't think twice about upgrading your LS1 with over 100k miles - and then run it hard without worry.
Now, what are you waiting for?
Thread Starter
Advanced
Joined: Sep 2009
Posts: 95
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From: Pittsburgh/Butler PA
I installed AFR 205 heads and a 224/230° cam in my '99 C5 with 155,000 miles on the odometer. It currently just rolled past 220,000 still with the stock shortblock. The only thing I did to the engine in the past 65,000 miles was to replaced the valvesprings due to the cam's .600" lift.
Quite going to whoever gave you the bad advice to rebuild your LS1 at 111k miles. Stay way from them. Absolutely go with a set of AFR 205s on your 346 - that is the engine they were designed for. Don't think twice about upgrading your LS1 with over 100k miles - and then run it hard without worry.
Now, what are you waiting for?
Quite going to whoever gave you the bad advice to rebuild your LS1 at 111k miles. Stay way from them. Absolutely go with a set of AFR 205s on your 346 - that is the engine they were designed for. Don't think twice about upgrading your LS1 with over 100k miles - and then run it hard without worry.
Now, what are you waiting for?
You just made my day!
Melting Slicks
Joined: Dec 2006
Posts: 2,186
Likes: 2
From: Woodinville WA
AFR 205's are awesome for 346 cubes. They may not produce the biggest peak HP number for a big cammed motor, but their throttle response and torque are often superior due to better flow velocity.
