turbotuner20v

do you happen to know of a quick reference guide on how to do logging? I'll check out the HPT forums, but didn't know if you had one bookmarked for people that ask questions.


on a mechanical note, I did get a cam spec from Tooley:

238(QXX)/259(HUC) .643/.632 115+5

lt1z

I guess we should clarify if rubbing constitutes clearing vs binding. Either way do what makes you happy. I will continue to use the 11/32 with LSA castings. The important point here is the OP should upgrade from 5/16 to something stiffer.

turbotuner20v

Where'd you purchase your 11/32 ones from? If I'm going to just 'do it while I'm in there' I'd prefer to go with the sure thing to avoid any new complications.

inspector12

See when I asked that question you told me they were 3/8" push rods LOL! Come on man. Now you see why I ask stupid questions some times. I agree with running something better I would run a 3/8's if possible, but on the black car with the AFR's I ran some .120" wall 11/32's I got from Erik, but Smith brothers as well as a few others make them. There wasn't any clearance for larger ones on out of the box AFR's.

DSteck

That's kind of a loaded question. Heh.



Also, as another point of info, last night we put the 3.8" restrictor on Chad's F1X. It hit 22psi at 7000rpm and was moving 165 lb/min. That's a 10% increase in airflow over what it was doing when he made 1200whp. 25X/26X cam.

SquatchMachining

There are no complications with 3/8" rods. I wish he would further elaborate on whatever issue he encountered. I have built at least half a dozen LSA headed engines in the last year and used the same Tooley tapered end 3/8" pushrods in every build including my own. No binding, no rubbing, Just make sure you order the correct length for your application, push rod length checker is priceless.


If going smaller makes you feel better, go for it.. But there are no issues that I have ever seen or been made aware of.

turbotuner20v

I just assumed for the couple extra bucks they upgraded to the 3/8" as part of the cam package, but if there's sometimes clearance issues I imagine they just go w/ the standard stuff.

turbotuner20v

These right?

http://www.briantooleyracing.com/ls-...set-of-16.html

For $100 I'll give them a try.

SquatchMachining

Yup.


And I believe my personal engine is damn near identical to yours when it comes to major components.. Gen IV iron block, stock stroke, stock GM lifters, unmilled LSA castings, factory rockers. Standard 7.400" length worked for me.

turbotuner20v

Ordered and they already shipped. I'll pull it apart this weekend and see what's up and at minimum at least upgrade the pushrods when it goes back together.

ajrothm

Why not do a compression test on it now before stripping it apart?...Easy and quick, just to see if the psi is equal across the board...Then leak down test it while you have it apart...

I'm sure its probably ok but...Couldn't hurt... I compression test mine every time I pull the plugs just to keep tabs on it. If I see anything abnormal, I move to the leak down.

turbotuner20v

Yea, I've comprsssion tested a few times and it's come back acceptable on all of them. I'll still do one too, but want to step the investigation up a notch.

First test after/during break in of rebuilt motor last September
166
175
172
172
175
171
175
175

Pretty sure this was cold test after tx2k
169
165
170
167
165
167
169
162

I lost my notes from the first test regarding which cylinder was which, so not a direct hole to hole comparison

Pitufina

Are the larger pushrods just a recommendation for safety or because his power? I've always felt uneasy using the 5/16s and revving to 7k. Would the btr ones work just fine with my factory ls3 castings? Sorry op just trying to learn as I go too. Thanks.

lt1z

Manton. You would want a series 3 11/32" .120 wall for LS engines in the correct length for your motor.

ajrothm

Those were all solid numbers...and before you have been recently beating on it with 24+ psi.... I'd check it now and see how it compares to the TX2k numbers (the 980rwhp numbers)...

If you see any of them down some, that "could" be some of the difference in the HP comparison to the X but... I kind of doubt its hurt...but you just don't know til you test it.

Leak downs are pretty finicky to do correctly and can definitely give you varying results...

Hopefully its nothing with the engine and just something with the X blower.... I'm sure a bigger cam will "help" but.... I still think there is something else too this... You're car made great power at 24 psi with the same cam and smaller blower so....

inspector12

A quick not so technical note is that when you start making more power the load on the valve train becomes more also, the larger push rods are needed as they deflect or bend how ever you want to see it. When loads get greater and that means also as the RPMs go up as well. It can act like valve float in a way meaning they act like a second spring etc...

Pitufina

I appreciate your response. That's what I was thinking that more power with the supercharger and a 7k shift point may lead to the flexing that you mentioned. I think that I'm to order me a set of the 3/8s from BTR. Can valve float or pushrods flexing be picked up as knock by the sensor?

inspector12

That I couldn't tell you for sure. I've seen a lot of things cause knock, but cant tell you that one for sure.

Louis Gigliotti

I'm still baffled that there isn't much of a timing mark at 25+ psi with a plug that's only 1.5 steps colder than stock.

inspector12

I didn't see and pictures of plugs. I'll look from home PC.