ZONES89RS

iTrader: (25)

Anyone running past 7000? I am on the rev limiter at 7100 in my LQ9, stock bottom end, no bolts or anything, it still makes power but i am not going to push my luck any more than i cam.

Now, i know the 6010 box can read to 7800 or so and i would like my next motor to be a SDT or .030 6.0 block with forged rods and slugs, and the end result will be a top end and cam that spin to 7700 or so to really scream.

Any of you guys ringing your motors out that far? What cam, springs and lifters are you using?

I have the single Ebay springs right now (conical beehives) and they are some stout *** single springs and my Trex seems to love them, they are good for .640 lift. But i am assuming a double might be needed if i dont want valve float, unless you guys can show me that they might actually work. I know the cathedral port heads have some pretty light valves to make it easier.

xpndbl3

iTrader: (23)

I wouldn't be spinning a single spring that high ever, but that's just me. PAC makes some nice springs and call bullet cams for a custom ground cam and you'll have no problem hitting 7700 or so, hope you plan on race gas type compression as well. You're looking at solid roller cam profiles and it won't be cheap, the real question is why do that instead of building a 408 that revs lower but makes the same power?

ZONES89RS

iTrader: (25)

Well, a 408 will require a crank that will cost more than i want to spend. If i find something used i will probably jump on it, but the stock 6.0 crank will work for me. Will be looking to 11 to 1 compression, or a touch higher. Going to stick with hydraulic, if i cannot get 7700, i will live, but i am sure i can get close to it with a hydro cam.

Plus, that much RPM sounds sick as hell.

LS_10

iTrader: (1)

I shift at 7000 my peak power is at 6600-6700

DMMizell

iTrader: (1)

I shift at 9200, have tried as high as 9700 so far.......

Pop N Wood

iTrader: (1)

I have always read it is the valve train and oil control the determines how much an engine can rev, not the bottom end.

Rev it too much and it won't blow up so much as just shorten the life of the motor.

NemeSS

iTrader: (127)

the engine i pulled from my ss would see 7200rpm shifts constantly.
redline was 7500.
243 heads were equipped with REV valves, some machine shop dual springs i used in the motors i built. about same as patriot gold extremes.
gm lifters, jesel sportsman series 1.7 rockers.
6.0 stock crank, rods. hypereutectic pistons.

ZONES89RS

iTrader: (25)

Hmmm, how high can the stock rockers go?

NemeSS

iTrader: (127)

idk. but they will come apart eventually. if there beat on constantly.
stock rockers spill there needle bearing guts.
you will prolly need yella teras or something similar eventually

250racer

iTrader: (10)

I went with comps trunion upgrade for my 403 it was easy to do and affordable.

ZONES89RS

iTrader: (25)

I heard they mod the stock units and they handle way better.

kmracer

iTrader: (1)

you're gonna spend a pretty penny on a valve train that'll spin to 7700+, alot more than you would spend on a 500 dollar crank.

melsie68

iTrader: (8)

I agree that a stroker engine would be a better option for many reasons but not necessarily price. Keep in mind you will need more than just new crankshaft. A stroker kit may come out a little more expensive once you get all the machine work done on the block and consider the down time, but I still think it is a better option. In the end the car will be more fun to drive and faster.

Quite honestly I don't really see how you will get that kind of rpm without the very best hydraulic roller style equipment. I believe you will need a high quality limited travel lifter like Morel, some very good valve springs and a cam that is still going to operate at that engine speed. I would suggest light valves- either hollow stem or titanium, titanium retainers and locks and the smallest diameter valve springs available. I wouldn't run single springs on anything performance oriented that is going to see past 6500rpm. I know a lot of people won't agree with that statement on the valve springs. At least if you have a dual spring and the outer breaks, you have the inner to keep the valve controlled enough to shut the engine down. If you really want to turn the motor that hard, you need to get the correct components for the job. Personally, I don't see the point, but everyone is different. If you just get some good heads and decent performance cam, it will sound just as nasty at 7000rpm or less and you will forget all about wringing that little motor's neck! Best of luck on the build.

ZONES89RS

iTrader: (25)

Will probably do a 6.2 or get some used **** for a stroker, probably be cheaper that way.

NemeSS

iTrader: (127)

your looking at round 2500 for some good **** like callies crank and good rods and pistons plus the machine work, bearings and assembly.
prolly round 4grand for short block.

try the 6.0 replacement pistons with stock rods and crank take it .060 over
375ci. and spend your $ on heads. and valvetrain. instead.
patrick g made over 500rw with the new afr heads and cam with 6.0
those heads would be the way to go instead of a stroker engine. imo

ZONES89RS

iTrader: (25)

Yea, a 6.2 will work fine and just spin it up to 7500 or so, think that will be great.

speedtigger

iTrader: (16)

I have an lq9 and I am curious as to what the regular RPM limit is for this motor might be. I purposely chose a milder cam so I would not be tempted to over RPM the motor. I am planning on keeping it below 6500.

ZONES89RS

iTrader: (25)

Let it eat man, these are not our old school SBCs, mine is on the rev limiter at 7100 and i am sure it would go allot higher if i let it, mine is all stock with a Trex cam.

JBarron

The higher you rev, the quicker the engine is going to wear. A stock bottom end is not going to look pretty after much of that. I would love to build an engine that revs to the sky too man, don't get me wrong, I just don't think it's the most rational way to make power, or to have a fun. I will probably shoot for 6500, because I really want whatever I build to last a long time.

ZONES89RS

iTrader: (25)

Well, "build" can handle higher revs all day, now the older small blocks are time bombs on higher revs, but the LS is designed to go higher and do it more efficient. Been beating mine to death since January this year, every time i drive it it sees the rev limiter at 7100 RPM and so does everyone i know with a stock bottom end LS engine, they dont wear much faster at all as they have low tension oil rings and a oiling system that is up to the job, with a combo like that, there is no wonder i have taken apart EVERY LS engine with higher miles, even my service truck 6.0 and they still have cross hatching in the cylinder bores, the old SBC cannot do that, they wear out so bad you have to get the ridge reaming tool to get the pistons out.