N/A motors in here!!!!!

**onebadws6_1998** · 08-07-2006, 01:49 PM

Hey guys have a 98 trans-am tsp 231/237 .598/.595 112....tsp stage 2.5 ls6 heads, level 4 (R.P.M 4L60e) vig 3600 2.5, mustang dyno'ed 408rwhp 386rwtq....problem is it grenaded #3 rod through block...trashed whole lower end as well as the cam and 2 valves. Have you ever heard of naturally aspirated ls1s Stretching rod bolts.....or oil pumps just leavin' ya? I already disassembled to block and all other bearings and caps look fine. Already have Tsp short block on the way and upping cam to tsp magic stick 3. My question i guess is, are there any known flaws in ls1 oiling system, or ways to improve? Also have question on milling heads. Was told .030" off heads will bring c/r to 11.2 . Your replys are appreciated .... Thanks

**Hi-Po** · 08-07-2006, 09:25 PM

I havnt peronally heard any Mayor flaws in the oiling system but maybe someone can chime in there with some info for ya. There are many things you can do to better the oiling system in all engines. Baffles in the oil pan can be added to keep oil around the oil pump in wet sump systems to prevent aeration(sucking air). You can also increase the depth of the pan if ground clearance will permit you. Usally not. Reducing cracnkcase windage is another goal in a performance engine. oil drain back onto the crackshaft causes a loss in HP. This is accomplished by crank scrapers, windage trays, and screens to remove the amount of oil clincging to the spinning crank. Oil pan kickouts also help direct oil in the pan away. Oil resrictors can be used that limit the amount of oil circulated to the rockerarms, and therefore limit the amount of oil that drains back toward the crankcase. Crank counterwaights can be Kinfe edged so less oil clings to them. In engines with oil drain back holes in the lifter valley, you can plug or block the the drain holes so less oil drains back to oil pan ffrom timing cover or rear drain hole. Get your oiling system blueprinted by a reputible place. Oh yea, Usually oil resticting is for race only app.

Question about milling. Whenever you mill anything, install over size valves, increase valve stem length to accomadate larger valve springs, and even grinding 3-angle valve seats will change your valve train geometry. Just a little FYI. Me personally, i dont care for milling, too much for involved with gettin everything back to norm. Off the top of my head i cant remember what the numbers are for milling. If i remember or find it somewhere ill post.

**99 Formula** · 08-07-2006, 11:42 PM

well mine didnt do that but i did SHRED some connecting rod bearrings and that cause a little dmg inside..but good luck with your build

**Redphoenix1998** · 08-08-2006, 01:21 AM

To Answer your question on the LS1's especially in 98, YES! The oiling galleries in the Stock 98 LS1 block are far less superior to that of the newer LS1's or the LS6 blocks. With the 98's, if you disassemble the rear of the block you'll see two small holes in the back, that's your oil galleries. Compared to the 01-02's and the LS6's, it's a problem. They solved it by ditching the two galleries and making one big gallery to add extra flow. The stock LS1 pump has more to be desired of, so upgrade to a ported LS6. If I can find or take pics, I can see if I can post the pics up.

**onebadws6_1998** · 08-08-2006, 11:42 AM

Right on guys .....building motor now and new has ported galley on back of where rear cover mounts...also did go with ported ls6 pump

thanks

**777** · 08-09-2006, 06:00 AM

It's somewhat common that 98 pumps fail. You should have upgraded when you put in the cam. I had that cam before and it made 386rwhp cam only.

**onebadws6_1998** · 08-09-2006, 09:54 AM

YEAH really loved that cam .... actually did cam swap almost 28,000 miles ago, motor has....had 93,000 on it....did you run those #s on mustang or dynojet?.....I dynoed at 356 rwhp and 341 rwtq cam only on a mustang dyno

**Fast72** · 08-11-2006, 07:13 PM

I work at a Gm dealer and I know that in the trucks we have been having problems with oil pumps. This has been newer and old models. I replaced an engine in a truck that was under 10'000 miles and I have replaced several oil pumps. The bypass valve in the oil pump starts sticking and causing oil pressure drop.