Some of you are familiar with my build Project LSxpress top dragster. I just redid my shortblock which consists of a filled LS2 block studded and girdled with a stock stroke K1 crank, K1 rods, wiseco 4.005 Pistons with the tool steel .200wall wrist pins. I also have a set of dry decked 243 heads that are getting CNC'd by PRC. Stock size ferrea stainless intakes and inconel exhaust valves. BTR .660 springs with Ti hardware. Ls9 gaskets with arp studs. The dragster should weigh as close to 1650lbs as I can get it. I have a 1.69 first gear Powerglide, 3.90 rear gear and big bubba 35-15-16 tires. I sold my cam an lifters that I was going to run and want to do something that will go 7500-7800 rpm. This will be on straight methanol, with 16 injectors in a proflow with twin s369sxe turbos. I am open to suggestions.

 

Sub 8000 RPM is still hydraulic territory, but since its a dragster and not a street car, a solid roller might still be a good idea.

And I just realized this helps you absolutely none.

 

Lol. Anything helps. I go round and round in my mind and get nowhere. That is why I made this post. I had morel 5290 street lifters originally but sold them. I am thinking custom hydraulic cam with a set of 5206 lifters and factory rockers with the bushing upgrade. The lifters are pricey but cheaper than solid lifters with good adjustable rockers.

 

My truck motor is a solid roller. I've been shifting it at 7700-7800. I'm not necessarily in what you would call non hyd roller territory. I did it from a reliability stand point. The added aggressiveness of the cam lobe was a bonus.

I'm in the middle of a few updates and we backed the cam up 4 degrees to see if we could get some rpm out of it. I'd like it to make power good enough to need to be shifted at 8000 rpm for the ol'truck to make improvements in et mph.

 

I am thinking that I don't want to spin the K1 rods too high. What lifters and rockers are you running? How often do you check valve lash?

 

All Crower ****. Lash doesn't move.

 

with the power these make in the mid range up to 6800 or so and guys running low 8's and high 7s running these rpms at 3000+ pounds . what is the real advantage running that high of rpm?

no disrespect I'm trying to see where the gain is. as every turbo engine iv seen likes to work and they liked it when you try to hold them back and let them work.

i know big hp numbers require high rpm. but holding the rpm down a bit might help it live longer an is a hell of a lot easier on valve train.

 

In my case, I am trying to run the fastest MPH I can. I am only 1650lbs but my 1.69 first gear is going to work the engine, when I shift into hi gear, my 3.90 rear gear with 35" tires that are growing, will need some rpm to get to over 200mph plus you have to factor in a small amount of converter slip that will raise the rpm.

 

Why not run a shorter first gear and step down from a 3.90 to a 3.73?

Most of the solid roller turbo setups around here are guys that are running 180+ MPH in cars that weigh 1200 lbs more than your dragster.

 

Well I already have the tranny built and the rear end is done as well. I am just trying to get it going. Keep in mind that the cars you speak of, aren't running a 35" tall tire. If I have to later, I will switch rear gears.

 

elky, I have thought about running a solid roller for the same reason you are. I can keep a higher number rear gear to aid in the launch, but I would still be able to mph out the back without tapping the rev limiter. And like blown06 stated, the added aggresiveness of the cam would be kinda helpful too. The only thing I am worried about in my situation, is that I have a mild build th400. I mean it has a billet front hub and input shaft, but not quite sure how well it would do spinning to 8000-8500. Hopefully it wouldnt blow the hell up on me. lol

 

Haha that is something to think about. In my case, I have a Reid case powerglide with all good parts in it. We do have a 65 ElCamino that I am building with my dad and it will be powered by a LS3 headed LQ4 carbed making 550ish hp with a stock case and internal th400 with a good valvebody and clutches. We plan to wing it to 7000 but ad 1000hp and another 1000rpm and you are asking for a shrapnel bomb.

 

Here in Australia, bloke has gone 1600hp and 7.99 (3800lb) on a hyd. roller with standard rockers and a trunion upgrade. From memory it spun to about 7500.

 

That is a stout pass. We have some fast hyd. Roller stock rocker cars here too, but I am trying to go 6.30s at 200+ and I just don't have the mechanical gear ratio to do that at only 7500rpm. I may have to try it and see what it will run. A rear gear swap would be cheaper than a good solid roller setup. lol

 

Why wait at all? I'm running a low lash solid roller on an NA street car that won't see over 7200 rpm and you couldn't pay me to go back hydraulic.

I am using stock rockers with shims instead of adjustable ones for now. I set it when I installed all the parts new and after about 3000 miles of aggressive street use the lash is still where I set it to within .001". Cold lash set to .000" and hot to .010".

I went from a 230/238 to a SR equivalent of a 234/242 (239/247 actual spec) and gained 20rwhp.

 

Why do you like it so well aside from the 20hp? I'm guessing there must be other nice attributes to it because 20hp doesn't merit the expense when you're in the forced induction forum. 20hp worth of extra boost is pretty much free. Lol

 

They don't get it

 

Although they make power, solid roller cams/lifters are a maintenance item...at least in the sbc/bbc world you should be checking lash AND pulling the lifters out on occasion to possibly catch a lifter that may be on its way out. Problem with the LS engines is you have to pull the heads to get to the lifters which kinda sucks.

 

I just saw the thread title on the main page and wanted to chime in with my experience. I wasn't really hanging out in the boost section lol.

The only difference in expense how mine is set up is the cost of the lifters. That said I've had mixed results with the LS7 lifters and would upgrade to something a little better anyway. Overall cost difference would be around $200. This of course changes if you use aftermarket roller rockers and valve covers.

You are correct the 20hp on a boosted vehicle isn't much. You were talking about spinning high enough the stability is of value to me. It's of value to me even on my mild setup. I also like that I don't have lifter bleed off at the track after runs like I did several times with the ls7 lifters. FYI, I do think the car actually gained a little more than 20hp as the car was discovered to be lean on the dyno but I did not have time to correct it for another pull. Still we would be talking about another 5-10 tops so small potatoes in a boosted application...I consider the power gain a bonus.

There is also just something about driving the car now that feels different in the way the engine runs. Smoother more explosive burst of power, seems to rev quicker...things like that which are very hard to describe but very apparent to someone driving the same car for many many years.

In my particular setup there is no additional maintenance. I've been checking lash to ease my mind even though Kip himself told me once it's set and broke in everything should be good for the life to the valvesprings. I only put 6,000-10,000 miles on my car a year. Spending an hour to pull the covers and check a few isn't a hassle for me.

It's not for everyone by any means, was just offering my experience since you sounded like it was something you were already considering.

 

thunderstruck507, thank you for taking the time to describe that! To me it is very useful information. I always feel a little funny about hydraulic lifters, but laziness and cheapness on my part always seem to keep me using them. Lol I figured there would be more to the story than just the additional power. Sounds like there is a subjectively different drivability feel to the engine that is nice, and rev freaks can be happier with them too. :-)

Are the bearings in solid rollers more likely to go bad and wipe out a cam than the ones in hydraulic rollers are?

Also, basic newb question: what is the additional expense on the top of the head to go to the necessary adjustable setup with whatever aftermarket rockers are needed?