My engine will be going back together this week and next (see my sig) I've been looking at posts and it looks like springs are very critical to the longevity of the engine and drive train. Right now I have the springs that come with the GM lt4 hot cam kit (and 1.6rr) but are these good springs? Are there better springs that I should buy that will last me longer and give me more piece of mind? I'm going to be spending a lot of time with the engine at high rpm's (autocrossing). Is there anything else I should be doing while this motor is apart that I'm not thinking of?

thanks,

Joe

 

Joe, I have the hotcam and the lt-4 springs plus, the 1.6's. The springs are adequate for street use but, I think you are on the right track looking at higher pressures. The Lt-4 springs are maxed out with this set-up. I don't get any noticeable float with them so I can't tell you they won't work. They work very well with my set-up. Maybe you plan on pushing them past 6,000 RPM's. I usually shift out right there. The cam does pull hard to 6,500. I just don't choose to push it that hard. Do you plan on running past 6k??

 

Pony up the additional `$150 or so for Ti retainers and 10deg locks to go with the springs.

They will lighten up the valve train which will reduce stress at high RPM.

The reason I added them to my valve train is to allow higher RPM without valve float with less spring pressure. This too reduces stress and wear on the valve train.

 

real good idea also get a spring checker and test after it get's
run hard.... even stiffer springs brake

 

I went with the CC 26918 beehives and matching Ti retainers and the cc 4705 cups. These springs require no machining and have the right intial pressure (#) and rate (#/in) for hydraulic lifters.

Eric

 

Eric - How many miles do you have on your CC beehive springs? Have you had a chance to pull them and check them after some use in the engine to see if they've lost any ##? Where is a good (read cheap) source to pick up a set of these?

I also bought a LT4 knock module and LT4 valve covers which showed up today (dangit! need bolts).

Ok I'll look into the ti retainers - makes sense that lightening up the valve train will reduce stress on the springs. My lightweight valves should help a little too.

I've got to say I'm not sure about running the motor up to 6500 rpm's is that safe? I'm very confident in the shop that's bulding my motor and they're standing behind everything with a year warranty, but I don't want to do anything that's going to tear up my new engine. Is there any HP at these rpm's with this cam because I would think you'd want to shift sooner? Anyone running their LT1 up to these RPM's and feeling good about it?

I got my coated Hooker 2151's from Jet Hot today and they're sweet! so, so, nice ... I was drooling on them after I opened the Fedex box! Where should I put the o2 bungs on my 2151's? I need them to clear everything but I know I need them as close to the primary tubes as possible.

I was at the shop today and we were looking at the stage 2 clutch disc from Carolina Clutch and thinking it looks a little weak. I don't want to have to pull this next year ... I'm wondering if I should go with a Centerforce or something instead?

I don't think I can install the heavy duty lt4 timing chain unless I convert everything over. Will I have problems running a regular timing chain with the LT4 Hot Cam?

ok I'll quit asking questions!

 

I am interested in the beehives as well.
Since you are lightening up your valvetrain for higher RPM's, flywheel choice will impact that directly also. It looks like you are going to a single mass?
You might consider chamferring the oil return holes in the lifter valley and oil pump since the block is apart. Will aid in smoother oil return/flow.


Same for the oil pump body.
Maybe deburr casting lines on the block to deny cracks a place to start, but that is really a bit much.
Let us know how it turns out.

 

Nah, I got 0 miles on 'em. The LS1 boys like them on thier 0.650" lift cams, they don't require machining on LT1/4 heads, Porsche and Viper use bee-hives, along with the LS1/2/6. What's not to like?

Jegs has them, but not the cups.

I got them because they never break. The LT1/4 retainers are known to break, esp in high rev applications.

6500 is a lot for a stock LT1/4 bottom end. They never last long at such high revs.

Are the 92 O2s heated? If not, I'd convert to heated O2s, then it's not a big deal about placement. My 96 has an extra set of O2 after the cats, they're heated so they work just fine.

McClod

I'd convert to the newer opti, but lots of folks have run 400hp through the stock timing chain, so the extreme duty chain isn't required. Another option is an electric H2O pump and a $100 Cloyes chain.

Eric

 

You might try Comp. Cams direct for retainers, locks and behives. They have great inventory, good prices and next day delivery.

 

Paul - Yes I'm going to the single mass how will this affect the valvetrain or are you just referring to quicker revving due to the reduced weight of the flywheel?

Eric - Thanks for the thorough answers I appreciate it.

I looked the beehives up $179 doesn't seem bad although the beehives with ti retainers will be $400 dangit. I suppose I can throw my LT4 springs and retainers on e-bay or something later to get rid of them.

What is the advantage to the cc cups? Sorry I'm still learning about these things.

I've got a brand new water pump and opti - At this point I wish I had bought a 96 for a few different reasons but I'll get over it.

I've heard of people using heated o2 sensors - this becomes necessary when moving the sensor away from the engine? Instead of grinding the ceramic coating off my headers to weld bungs can I put the o2 sensors after the headers if I use heated sensors? (I like this ) Moving the sensors this far away and switching to a heated sensor won't compromise the integrity of the sensor reading?

I notice from your sig. you've got 30mm/26mm solid swaybars is this a good setup? I want to set my car up for autocross.

thanks,

Joe

 

LOL, I have a brand new set of the LT4 springs with cups and retainers, plus the set on my LT4.

No advantage to the cups, they are required to hold the springs in place and not eat your aluminum heads. The best part of the CC 26918 springs is they are great springs that don't require any machining of LT1/4 heads.

Put them on e-bay with your springs.

I am not an expert on heated O2s, my two 96 LT1/4 have them and they work. Maybe you could starting another thread specific to this.

I've done a bunch of mods to my Vette, but nothing gave me more bang for the buck than the 30mm/26mm solid bars with poly bushings. Cost was less than $250. After that, the next best mod was my 4.10 gear and rear poly bushings ($600 with parts and actual gear swap labor).

Eric