Hey guys, I got a quick question about my lq4 and cam decision. Heres my specs so far:

1984 Trans Am converted to 1988 Formula

3.45 geared 9 bolt for now

2003 lq4 short block
factory dished pistons
TEA stage 3 5.3 heads with 58cc chambers
.650" lift springs
ls7 caddy lfters
Hardened pushrods

T56
spec 3+

I currently have a ms4 and a tr224 sitting on my shelf. Everyone tells me that the ms4 will give me piston to valve clearence problems.

What will the power differences be between the two cams?

Should I get my pistons fly cut so I can run my big cam?

I plan on running about a 100-125 shot on nitrous

Should I look into buying a new set of pistons for the spray taht are already fly cut?

What would you do in my situation?

 

Sounds like a good question to post in LS1tech. Alot more of the LSx community rolls through there than here. I will say its always good insurance to use the clay to check PTV clearance vs listen to online help. Same for measuring PR length vs guessing with aggressive cams

It does sound like a nasty 6.0 though

 

I can't help you on the PTV clearance question, but the power difference can potentially be between 35-50hp difference.

Texas Speed's site claims a 30-35hp gain over a stock motor with the 224R, and up to 80hp gain over a stock motor with the MS4.

 

MS4 is too aggressive a cam for your gears. I wouldn't use it unless you go to 4.xx gears. If not then you'll have a lot of trouble getting the car rolling in first gear with the T56 and the car will be pretty slow until you get revved up to about 4500 RPM or more.

 

Put the ms4 in and check for PTV. Its a decent sized cam and would be better with steeper gears but it should work ok well tuned.

MS4 will make a good bit of power over the 224 and the MS stuff loves spray. I wouldnt fly cut and spray but some guys have done that just fine. If you had an idea how much PTV you had, i'd sell the 2 cams you have and get a custom grind with a tad bit less duration than the MS4 and maybe a tad bit less lift as well.

 

Thats not entirely true. I agree to some extent but I have been driving mone with the MS4 with t56 and 3.42 gears for a year now and it's not as bad as you'd think. There's a bit of cam surge or "bucking" at low speeds/rpm, but it's doable. It might be annoying in a daily driver but certainly wouldn't keep me from going with that cam over the 224. I'm swapping for 4.10's in a couple of weeks which will help get rid of most of that issue though. The thing I love about this cam is it's an absolute screamer in the upper register.

 

Rear gears aren't an issue because I'm going to upgrade to a stronger rear end with 4.10, 4.30 or 4.56 gears depending on tire size. I'm just worried that I'm going to under cam my engine. I guess I could buy new speedpro pistons and scat rods for 600$ or so. I'm just not sure what way to go.

 

That the exact situation I'm in right now. Can I run a thicker head gasket for more space??

 

That the exact situation I'm in right now. Can I run a thicker head gasket for more space??

 

Does this car need to be reliable or is it a toy? Hard decision with a set of nice heads that could be destroyed.

 

Needs to be a reliable toy it's just a weekend drag car toy

 

Unless you can find someone running this exact combo, you wont know if that cam will fit or not til you try it. It certainly wont be undercammed with the MS4.

 

All you need to do is call Texas Speed and ask them what heads you can use with the MS4 on a stock LQ4 short block. They've put enough engines together to know. No need to use exactly the heads you have in mind. There are other good options out there.

 

I can't find a single person with a lq4,ms4 and 58cc heads.

 

I called them and they won't tell me anything for whatever reason. The 58cc heads aren't heads I have in mind. They are new tea stage 3 5.3 heads that I already have.

 

Sure they will. You just asked the wrong question. Tell them you have an LQ4 short block and you're wondering if you can use their 5.3 heads with the MS4 cam. If they say no, then ask if any heads can be used with stock pistons. Believe me, they will be quite helpful if they think you are shopping for a set of heads with that cam.

If both answers are no, then you should consider the MS3.

 

I tried twice now. First time I said tea and matt wouldn't say anything. Second time I tried I said I wanted 58cc to up my compression to 11:1 and said not possible with a ms3 but wouldn't say how much needed cut.

 

Why not get some 317's if you want to run that cam? You can pick up a bare set of those heads for around $100.

 

I have a set of 317, but I have a amazing set of tea so why not use them

 

The problem also lies int he head itself man, the TEA heads actually drop the valve height outward towards the piston, losing even more PTV. A set of 243 heads would have been the way to go. See if you can find someoen to trade you, ported for ported or the 243s and some cash your way, 243 heads milled .030 wil clear with the MS4, mt Trex clears with .110 with 317s and the 243 and 317 have the same valve height.

 

Just run a smaller cam then with the heads you have. If they still have good port shape and flow well, you wont give up much with a cam with less lift and duration. These motors do well with mild cams because of the intake/head flow.

 

Smaller like ms3 that won't need as much ptv?

 

exactly, something like that. If you had an idea of the valve opening/closing points you can kinda measure the lift til you hit the piston at various degs after the valve begins to open until it closes. It can give you an idea what cam profile will fit. You can just hang the valve on the head with the valve locks only with dial indicator on valve stem, and rotate the motor with deg wheel til you contact the valve and then sweep the range, getting an idea of the lift curve and duration points on the deg wheel for each valve.

example, Comp 285ls hr13.... it opens 32 deg BTDC and closes 72 deg ABDC advertised. you will have most of the lift coming in between 32 deg btdc and like 70 deg ATDC.
Exhaust valve opens 88 deg BBDC and closes 30 deg ATDC. So most of your lift concerns will be between that 30 deg ATDC closing point and something like 70 ABDC. Just rough figures i'm not exactly sure what numbers it will be.

 

You sir are very smart. I'll try that. On a plus side I hear the ms3 loves spray lol.

 

Both of the magic sticks love spray, you can't really go wrong with either one.

 

Did you lay down 420whp on stock heads?

 

317's

no porting and polishing, stock valves, just enough shaving of the deck to get a smooth surface

 

Fixed it for you

 

Wow thats pretty impressive. My buddy has a 02 and either a magicstick 3 or 4 and made 420 with evey bolt on and tsp ls6 heads. How much extra power is the .3 liters worth lol

 

Good call

 

Most of the gains in the extra few cubes is in the torque from what I've seen and heard. It takes a LOT to get the 5.7 over the 400 ft/lbs mark.

 

Well, IDK what my 89 is making at the back tires, but pulling the tires off the pavement and turning 7.1 at 97 at 3450 race weight is doing something right, stock 317s milled ,030.

 

I have tea 317's and love them. For a good all around camshaft if you were to buy one id look in the 230-240 range... Bigger isnt always better.

 

What does that convert to in the 1/4?

 

31 @ 24mph...

It snapped the driver side axle first time out in the water box.


Edit: nevermind. I just re-read the post and I originally thought you were shortening convertible to convert. LoL

 

Lol it's cool. A guy on ls1tech said the most you can fly cut stock pistons is .120. Can anyone tell me if I will for sure be able to clear a ms3 cam? If I can find out I'll buy the cam and have my buddy check my ptv for me so I can get my stuff cut.

What y'all think? Also any hp guesses?

 

Can you assemble it with the MS4 you have now and see what happens with PTV? You will need to make a makeshift solid roller or use a very lighweight checking spring to measure everything

 

Can I use a little thicker head gasket to give me some extra ptv clearance?

 

Yeah you can but watch your quench height...too much will hurt performance alittle, and may be detonation prone. You can also try advancing the cam on the install to get some clearance here and there...depends on how much you have to begin with. Atleast check with that cam first to get a starting point on how much room you have

 

Am I correct in thinking that a thicker gasket will help me clear a ms4? Speed Inc has cometic gaskets from .040 to .120 thick. How thick should I need?

 

yes a thicker gasket will help gain clearance but how much is needed is not easily known unless you had an idea how much clearance you have to begin with. I'd rather see proper gasket thickness for the engine and have a cam made to fit instead of trying to fit a cam by throwing gasket thickness at it.

 

I'm gonna try to put the cam in this week.