LS1 Heads

[Phantom]

I've been talking with a guy on LS1tech.com and have been told some interesting things. First was that evidently the '98 motors have stronger connecting rods, crank and lower end bolts than the later models? I haven't been able to verify that but thought it was interesting.

On to the real news. We're talking about going to an LS6 intake, porting my heads, installing a better set of springs & valves and a 224/228 duration cam with about .580 lift. Evidently other LS1's he's done this on have dyno'd around 430 RWHP and 390 lb-ft of torque. It will also allow me to up my rev limiter to 6,500 and get a bit more use out of my existing gears.

What do you guys think? Does this sound reasonable based on your experience?

At this point it's about $1,500 parts & labor to do all this which sounds pretty reasonable to me. The worst part is that my car will be down about a month.

[mas28O]

You might want to look into using the 5.3 heads insteed of the 98 heads. You will need some new valve covers with the 5.3 heads. Your car should be down for only 1-2 days if you get all of the parts 1st. 224/228 cam is a good cam, are you going with a 114 or 112? I made 405rwhp cam only in my 240z 225/225 589/589 cam. Good luck

 

Mike

[Phantom]

Mike,

 

Not sure about 112 or 114. What are the pro's & con's? Actually I'm looking at spending an extra $150 and getting a set of '99 or newer heads and departing the peripheral bolt down pattern for the newer style. I don't think the '98 head has any advantage over the newer ones - only disadvantages. That could also drop my down time to a day beacuse it would essentially just be a parts swap.

[Mikelly]

Wait until tomorrow and I'll be able to give you the skinny on my build. I'm going down to Durham NC. to have the final LS1 edit done on the new motor, and get some dyno numbers. I'm using the TR 224/224 cam with 114 LSA and some 98 ported heads with 2.02/1.57 valves.

 

Using LGM long tube headers, LS6 intake/injectors, ported TB, and a full 3 inch exhaust with SLP cats.

Mike

[Phantom]

Mike, No problem waiting. My wife has other plans for my money right now. I'd really like to see your dyno results! Betting you'll be upwards of 450 HP & 400 lb- ft of torque. What I'm really interested to see is what it's like on the bottom end - down between 1,500 & 2,000 rpm because that is cruise rpm for my car.

 

No way mine can do as well because I won't have long-tubes or 3" exhaust but it will be indicative and the low end should be very close.

[DaleMX]

Phantom, the 98 heads have a different bolt pattern for the valve covers, and the mount for the coil brackets is different. Lower LSA develops power a little lower in the RPM range and idle gets worse with it as you get lower. I'm running Stage II 5.3 heads and the TR230 (LSA 110).

 

Tunning is the key with cam and heads for sure. I battled mine, but finally got the tune just right.

 

Be carefull with heads, some of the cheaper LS1 heads are sporting 225 or larger intake numbers and that will hurt your low end torque.

 

I agree with Mas and am really happy with the 5.3 heads The extra compression is not a problem with 93 octane gas. I run a little rich, and my timing is 28-30 with no knock. It screams. IF you go this route, you will need to get coil packs and valve covers.

[mas28O]

Mikelly, is using LGM long tube headers, they will make alot more HP than the 1.5" headers that you are using. So it might be hard to compare his ## to yours. Mikelly, I think that you will make 430-442RWHP 385-410RWTQ If you are using a 346 ls1 (let us all know).

 

I have used both the 112&114 LSA The 112 has more mid range power but the idle will not be as nice as the 114. The 114 will have a broader power range with a better idle. I am using 228/228 589/589 112 in my 240z and a 236/236 605/605 115 in my 402 ls2 RX7. you might want to look into some better headers for your car, ls1's like big headers.

 

Joey(LS1z) is using the 228/228 589/589 112 cam in his ls1/280z, you might want to get some feedback from him.

 

Mike

[DaleMX]

Phantom, I thought you had Sanderson's. I know the Sanderson's I got were 1 3/4". If your at 1 1/2 you gotta step up to 1 3/4 and true dual 2 1/2" or 3" for that cam and heads or you'll be loosing out big time.

[Mikelly]

Correct on all acounts...

 

MAS, I'm using the standard LS1 block and crank, with Eagle Hbeam rods and Ross pistons. Compression is 10.5:1. If I hit anything over 400WHP, I'm gonna do a backflip.

 

I went with the 114LSA because the Vette is a 99 model and we may eventually get mandated emissions inspections in my county OR I may move into another county that requires emissions testing. This car has got to pass emissions and from what Thunder Racing told me, the LSA was key to ease of tuning for both power and emissions... 112LSA was the break point (Can be done, but more tuning is required), according to Thunder Racing, So I played it safe and went with a 114.

 

I'm heading out in a few hours. I'm going out to the garage this morning to bolt on the Z06 MASS meter I had sitting in the box. Jeff wants me to drive down with it in place so he can see how far off it is from the current Air tables...

 

Mike

[Phantom]

Dale,

I'm the prototype for the John's cars stuff so I've got 1 1/2" primaries into 2 1/2" collectors to full 2 1/2" duals to the rear with an 'X' pipe. If I change out headers now I'll be pushing the cost of this up another 50-70% or more.

 

Educate me - what is the advantage of 5.3 heads? Are they just better in stock form so I could just get stock heads & coil packs or what? Obviously the affect the CR. What does it go up to? The LS1 is at 10.5:1 now which is getting up there for pump gas. I have visions of raiding under the hood of my 2002 Suburban.

 

I can tell from what y'all have said that I'll be wanting a cam that has a 224/224 duration with .588 lift & 114 LSA.

[mas28O]

Mikelly, When I used the z06 maf the Air tables where off alot. On my 402 ls2 I am running it mafless.

 

Phantom, The main advantage to the 5.3 is the smaller chambers, you want to raise your CR up to 11:1 and you will pick up some TQ. I am running over 11:1 CR and 28 deg of timming on 91 oct gas without any problems. Good Exhaust is a key to being able to run hight CR, You will need the 13/4 Sanderson headers to be able to run 28 deg timming on your car.

 

Mikelly let us know how it goes..

[kraymond]

Here is some discussion from LS1.com and Patriot Heads. I plan on getting a set of them.

 

 

http://ls1.com/forums/showthread.php?t=1447&highlight=patriot+heads

 

http://sites.reachtheworld.tv/waterNew/default.asp?T=505233&DID=1225

[mas28O]

Try and stay away from Patriot Heads, Look into some TEA heads if you want some better quality.

[Phantom]

Actually this all started from me talking with a guy in this area that is a custom head builder so I had no plans for Patriot or even TEA's at this point.

[Guest zfan]

Off the subject but couldn't help notice the lift your getting on that launch Mike (MAS280). Are you running a front swaybar? What suspension up front?

Thanks,

mike

 

Bill,

 

Your going to really need some new sticky tires with the cam/heads/header upgrades! Going to be one mean bugger.

 

Mike

[mas28O]

Z-fan I am using a stiffer front sway bar with coil overs on my 240z. That is what the car looks like with a 1.50 60'.

[DaleMX]

Phantom, the stock 5.3 heads will hurt performance as the valve size is too small for the 5.7 LS1. I had mine ported and larger valves installed. The smaller chambers will yield around 11:1 when all is said and done, but the LS1's seem to like them. Your porter should be able to give you the low down on them.

 

I also have dual valve springs (Comp cams 977's), titanium retainers and locks, hardened pushrods, and Yella Terra 1.7:1 rockers (I think about 275 bucks). I think the heads cost me about 1,600 bucks. While I had the cam out and heads off, I replaced the oil pump with a ported one from Thunder, and also did the dual timing chain upgrade, and new Comp Cam lifters. I think that cost was around 700. Then the LS6 intake I got was damaged so I ended up paying 60 bucks for it and fixing it. Of course all that HP needs a stage 3 clutch to hold it, so tack on a new flywheel and spec stage 3 clutch (chatter chatter). 75 bucks for the flywheel on ebay and 325 for the clutch from thunder.

 

With the smaller dia headers you might not get good scavaging, but I believe that there is a cam out there that addresses this issue and still makes really good power. I'll search LS1tech for it and post it later.

[DaleMX]

Here's the thread go about 6 posts down to Pat's post.

 

http://www.ls1tech.com/forums/showthread.php?t=250905&highlight=stock+exhaust+cam+power

[Mikelly]

Dart is getting ready to release a new set of heads for the LS1 and they aren't priced bad at all, considering you get the built head, with titanium retainers, and springs up to .630 lift, for under $1400 for the pair.

 

Yesterday, when I was getting the bad news that these heads aren't going to support my goal, I asked about what to do next. Jeff recommended the ASA heads or a set of LS6 heads. He said to much porting and clean up has hurt these heads, which is also why the Patriot heads out of the box are so "hit and miss" on consistancy.

 

I'm signing up for a track day rental in Richmond on the 11th of November, So I'll have an idea of what this Vette runs in the 1/4 then.

Mike

[Phantom]

Dale -

 

Thanks for looking up the link on the heads. Very good information. I talked to my head guy and he definitely recommended not doing the heads until the cam had been upgraded. Evidently it's an absolute necessity to gain the benefit of the head work. He also thought the cam like Mike has would be a good one. I'm going to investigate the other one tough. I need to see if I can get some comparative data on them.