Like the title says, give me some suggestions or opinions on what you would do differently, without much change in the budget.

I had a junkyard 5.3l in my 95 z28 that spun a bearing followed by a t56 and a stock 10 bolt with 4.10s.

Im about to buy a new shortblock. Im strongly leaning towards the 370 with forged mahle flat top pistons from TMS due to good reviews, very fair pricing, and great customer service. $2500 to $3000 is my budget for a shortblock.

My 5.3l spun a bearing during the second of 2 40 rolls and i was only shifting at 6k rpm, so im frightened to spin any higher than that, but i probably will. Anyone have any ideas why it spun a bearing? The oil pump was a new ls6.

Anyways, on to the build. Most likely the rest of my setup will remain the same no matter what shortblock i choose.

Ill use my 862 heads with ls1 intake valves, and had some kind of back cut behind the valves. I have ls7 lifters and comp hardened 7.4" pushrods. I have the loathed 85mm bbk intake with a 85mm throttle body, 42lb injectors, pacesetter longtube headers, spec stage 2, stock flywheel.

With the loss of oil pressure my tsp 233/239 cam was ruined. Ill probably go with the trex cam, required valve springs, and a melling pump, as my dad is running that cam in his ls1 and it runs very strong.

I dont really car about horsepower numbers, i just want to run 11's in the 1320 n/a. The suspension is stock besides an eibach pro kit and lca relocation brackets. I frequently autocross and the suspension will be getting strano sway bars, adj lcas and panhard bar, and other corner carving goodies that i know wont help in a straight line, but the goal for the car is to be competitive in the turns yet run 11's. Next year a 150 shot will be in order.

Let me know any suggestions or anything thats wrong in my setup that you would do differently. Im sure it wont have a problem putting down 420 rwhp. Im also looking for tips on how not to f*** this engine up! It should be running by the end of the month hopefully before the track closes. Thanks for any criticism, suggestions, ideas, anything.

 

Well I would mill the **** out of the stock heads to get compression up as high as u could, since your running them unmodified.. It'll run good, be a torquey sob.. Check piston to valve clearance, and let Er eat..

 

And to add, y the other one pacman'd a bearing.. You'll never know.. Hard to say but rpm probably had nothing to do with it.. These motors spin, unles you're rattling the piston due to a **** tune it was probably just it's time..

 

Thanks for the input. About the old 5.3, i had a tune on it with a 235/249 .575/.59x 109lsa cam, and then that motor grenaded due to my incorrect installation of arp rod bolts. So i got another 5.3l and put the tsp 233/239 .595/.603 111 lsa cam in. Do you think thats enough of a difference to cause a motor to spin a bearing?

 

Ive decided to get my heads ported by a local shop for $600. Thats a bargain as far as i know. Let me know if anyone knows of any better deals. Im going with the trex cam for sure. Dyno or track guesses? Pics to come in a couple weeks, not that its astonishing or anything. Hopefully ill have a track time before dyno results but it all depends on weather and timing.

 

a local shop porting heads is not enough detail to determine if its a deal or not. What all are they going to do for 600.00?

 

Be careful, if it too great a deal its usually not.. Have they done any ls stuff to compare to?

 

Well i havnt asked any details he just said a 50-60rwhp gain. I trust him 100% though, my brother, dad, and i have been using him for about 11 years, he started with lt1 stuff now all he does is ls1/lt1 work.

 

Ok, just hear of experts all the time, making cars slower... don't want that to be you...

 

Thanks guy!

 

like he said above mill the heads down to get the compression up, also some port work could never hurt!

 

Static Compression should be around 10.5-10.8, idk im just guessing. I dont really want to mill them because i dont want to change pushrod length, i already have comp hardened pushrods

 

What valve springs are the most reliable? Patriot golds or extremes? PRCs? I need a few reviews

Bonus vids!

when it was a lt1 with a cc503 cam
cc503

with the 5.3l swap
Comp "***** Thumpr" Cam
5.3l swap

Autocross Lap with stock suspension (besides eibach pro-kit), 295/35/17 kumho ecsta v700s on back, 275/40/17s on front, full weight 95 z28 with 5.3l, 233/239 tsp cam, t56, 4.10s.
Still managed a quick time on the first lap with cold tires and no prior practice on that track combination
Despite what everyone thinks about sticking a bigger cam in a 5.3l, it felt decently strong
first lap 5.3l autox

Night lap on crappy cell phone
Night Lap

Me driving my brothers 02 z28 for the first time with a 228 something cam, fast 90, t56, 4.10s, strano springs, umi sway bars, adj lcas, panhard bar, and torque arm, strut tower brace, deleted abs, 315s and 295s, brembo front brakes, kyb adj shocks and struts
you can see how much better it handles than a basically stock suspension car
02 z28

good lap in my brothers car when it was stock last year, but it had the same aftermarket suspension as now, minus the torque arm, new tires, and it had eibach pro kit springs,
stock ls1

 

Well since nobody has any suggestions on valve springs i have another question i hope someone can shed some light on. I have ls7 lifters with about 750 miles on them that went through two engines that both spun bearings. I dont see any visable wear or damage but can a spun bearing cause some kind of damage to a lifter thats not seen with the naked eye?

 

Anywhere oil can go, you risk contamination from bearing material.. Cheap insurance to just buy new lifters..

As far as your springs go, you shouldn't go with more spring than you need.. Lots of folks run the patriot golds and the extremes on mild builds, me personally I love PAC springs.. If your Gonna run a trex or similar I'd look at the PAC duals, 1221 or 1521.. Enough pressure to handle what your doin without collapsing lifters cause of excessive pressure..

 

Thanks you have some good insight. Anyone have any experience breaking any of these springs? And what cam where you running when one broke?

 

Haven't broken any.. Thankfully..

 

Well the engine will have 4.030 -4cc forged mahle pistons, eagle h beam rods, and arp rod bolts with a stock crankshaft. The heads will have stock ls1 valves and the guy whos porting them says they should flow about 290 cfm. He told me, which i already knew, that my bbk intake will be killing me. So Ill probably get a fast 102 down the road after its running. He said the fast 102 should give me about 40-60 more horsepower than my bbk. Sound about right? He also said he has a cam for me but i didnt ask the specs yet, but he said ill be able to use my valve springs. I told him i wanted a max effort cam.
I was wondering if anyone has any idea of the potential of this build? Im just hoping for mid 11s but what is possible with my set up?