Eshaw81

So, I have a 97 6 speed Camaro that I picked up on the cheap. It has a spun bearing and needs a rebuild. I also have a ton of old lt performance stuff laying around from another car i played with a few years ago. I pretty much have a complete lt4 top end with all the valvetrain components and upgrades and a 503 cam. I also have a good bare block that has been cleaned and checked good. Its stock bore. Here is my plan...

I want to keep the budget for this car under $7500. I only want to do engine upgrades if they are necessary. My goal is an auto cross car capable of an 11 sec 1/4 mile. Here is what I want to do with the motor...

Since the block is good to go, I would like to not cut into the cylinder walls. But I do want the benefits of a stroker. My plan is to do a 377 (3.75 scat 9000 crank, stock rods with arp 7/16 bolts, and a decent set of 4.000 bore Pistons). I would like to do this with the 503 cam that i already have. The car will have the other usual bolt ons (cai, headers, exhaust, etc) with full suspension upgrades and 4.10 gears.

My question is will this setup get me into the 11s? I'm willing to bet money that it will but this is my 1st f body so I'm trying to maintain my expectations.

And please, I am no newbie to lt1 builds. I don't want to hear about forged cranks or doing a 383 or sending heads out for port or getting a new cam. I am working with a good shortblock, a scat 9000 crank, factory 5.7 rods with arp bolts, a 503 cam and a complete lt4 top end with upgraded springs, and hyper Pistons.

What should I expect from my "503 cammed, 377 stroker lt4 motor??" Can I plan on having an 11 sec car?

myltwon

iTrader: (1)

You can expect 112ish mph trap from a stock headed CC503 cammed car so I don't see why not around a 114-115mph with better heads and more compression. That's good enough for 11s assuming you can get the power to the ground and drive it.

Any reason you want to resize the stock rods? You can get into a decent aftermarket rod for around the same money these days.

Is the scat 9000 crank cast? If so I wouldn't put it in. Cast aftermarket cranks are not worth the effort. I know you don't want to hear about buying a forged one but I made the same mistake once and have a broken 3.75 stroke cast crank sitting in my garage that's split into two pieces.

BALLSS

IMHO I would stay stock crank, re size stock rods, re-ring stock pistons. 503 cam and send the heads off to Lloyd. Use the good block

I bet you would spend about the same, likely less, using stock crank and using the $ for LE heads vs buying a stroker crank, new pistons and balance

will the 350 hit 11's....with the right supporting mods, good diver and of course forgiving DA and track prep...quite likely

Eshaw81

I don't have plans to re size the rods, but only to use arp bolts in them. And the scat 9000 is a very quality piece unlike its eagle counterpart. I've seen too many of em hold up to way more power and rpm than I plan to throw at them and have yet to see one break (knock on wood). Honestly, I wanna just use the stuff I got laying around to build me a motor and I'm hoping for 11s. If I don't get it, so be it because I'm building a road racer anyways that I want to be capable of an 11 sec pass.

Eshaw81

Actually the new crank, pistons and balance comes to a little over $800. Lloyd wants that +$100 for a set of LE1, which he admitted to me long ago wouldn't flow much more than a set of pocket ported lt4s like what I have, or at least the minimal power gain to be had isn't worth the cost. Also, I want to do the stroker crank because I gotta get a new crank anyways so why not do a 3.75 that is a straight up drop in stroker crank that requires zero clearancing of the block. I'm mostly concerned about that 503 being s big enough crank for a 377. Im pretty confident about this build but that 503 is what would change the game. If I can find out before hand whether or not I need a new bigger cam, then I'll just scrap it all and go with an LE2 kit, but I'm not rushing out to spend $500 extra if I don't need to.

And yes, everything else on the car will be upgraded properly...suspension, gears, rear end, bolt ons, etc. those mods are taking up the vast majority of my budget which is why I want to reuse as much as possible of this stuff I got laying around for my engine.

BALLSS

didn't know your stock crank was bad (saw spin bearing so figured a .010 grind would clean it up)or the LT4 heads had a pocket port so yeah the stroker crank/377 would be a direction to go in with the 503.

Is that total combo going to get you most ET bang for the buck, no but as you note it is using parts that you have. Ask Lloyd about a cam with your LT4 head/377 combo....may be worth the $ for a custom grind from him and you could always sell the 503 to help offset

I have a Scat forged crank....but sadly can say I am also a member of the 2 piece cast crank club....it was a Eagle crank.....so just sayin "cast" and off shore cranks have quite a few failures

or another option...

if your stock crank is salvageable, re-sized stock rods w/ARP fasteners and new rings for stock pistons and a hone and get a full LE2 package and sell your H/C

Eshaw81

I would sell my lt4 top end and that 503, but I need the aluminum heads from this Camaro to send to LE to use for this 383 for my 96 Impala I'm building to chase down yours and a few other b-bodies from the impala forum. oops...did I let the cat out the bag??? Lol. That's another reason for my budget being what is is because I got bigger plans for my Imp.

myltwon

iTrader: (1)

Iirc if you upgrade the bolts you have to resize them which will end up costing around $200 or which is basically the same as new rods with arp fasteners.

BTW running a 3.75 stroke crank will require block clearancing at the bottom of the cylinders.

Eshaw81

Neither of which is true. I ran arp bolts in my lt1 build back in 2011 and the rods didn't need resizing, just bolts pressed in. But just for ***** and giggles and only $100, I may have them resized anyways just because they came from a block that I don't know much about. Also, the scat 9000 crank with stock rods clears these blocks plenty. If anything from what I've see is that I may have to grind one or two spots on the pan rails. This is why I'm so confident in this crank. I know too many people running it with success. It'll save a lot of people a lot of coin if they can just get past the "cast is junk" reputation that eagle has created.

rechtien

I have a used set of LE2 heads boxed and ready to ship if you change your mind and decide to go that route. Certainly cheaper than buying core and sending them in. New springs and valve seals. Had the machine shop resurface and vacuum check. 160lbs on the spring seats. Should work for the 503 or maybe a bit more cam.

BALLSS

...good you have your priorities right. The B-body get the 383/LE2 kiss

I think 11's with the package you note will depend on low 60' times and good DA.

myltwon

iTrader: (1)

Do you already have the bolts lying around or buying them?

I meant to say arp bolts + resizing would be around $200.

Eshaw81

Yes I already have the bolts laying around for another build I was doing back in 2011. That's why I have most of the stuff. As I was getting ready for that one, life got in the way and stopped progress. And $200 sounds about right.

SS RRR

iTrader: (2)

If you want the best of both worlds between straight line and auto-x/road racing I would start searching for used parts. I'd change out all springs with progressive rate springs and stiffer rear shocks. I'd try to find some used adjustable shocks for the front. I'd get lower control arms and if the car is lowered, or your plan is to lower it, then get weld on relocation brackets. I'd also make sure all bushings were in good shape. I'd then try and find 15" wheels and put on a good pair of drag radials.
As far as the engine is concerned I think you will be choking the motor therefore it'd be a stretch as to whether or not you'll be able to get into the 11's. In this case it'd be a matter of a good launch to take full advantage of the amount of torque you will have at lower RPM and will be fighting against a dwindling power curve. If you don't care about the interior of the car then weight reduction may also be necessary.
I got real lucky with my SS. I ordered it with the "Level II" suspension which has poly bushings all around, Eibach progressive springs and Billstein shocks. I drag races far more than auto-x'd so I put on some Koni 1-way adjustable shocks up front. Car is also lowered so I did boxed LCA's and relocation brackets and was able to get 1.7 60' times and best times of 12.0 @ 115 when the car was full weight and using BFG DR'S on 16" steel wheels. After my last engine I added a chassis mount torque arm along with a thicker rear sway bar and was in the 1.5 60' range. Always used the stock wheels up front when racing. Car still cornered like it was on rails. All trial and error on my part and I just got lucky.

Eshaw81

Thanks for the reply. My goal is actually a auto cross car that is capable of running 11s on the track. I know a guy here in Atlanta that did a road Atlanta run and had a pretty respectable time, then he drove the car to the 1/4 mile track and promptly ran a high 11. I been wanting to do that since I saw him. And the best part about it is the car can be used as a daily...a brutal daily, but still a daily nonetheless. As far as the relocation brackets, I see some that are bolt on. Thoughts on that? I want to use as much bolt on stuff as possible because I'm a stickler for working on my own stuff...it's a pride thing for me and I've had a few bad experiences from some "reputable" shops. As far as wheels go, I was planning on 17x9.5 at all corners with a 275 tire up front and a 295 tire in the rear. And I never thought about the heads maybe being choked out because I know the lt4 spun to 6500 and I've seen a few spin to 6800 and still make decent power. I'm leaning towards just getting a custom cam from LE and just calling it a day because he already told me the lt4 heads are a decent piece and flow about as much as his ported LE1s. Funny thing is I have the interior pretty much taken apart now and I'm debating which pieces to leave out. But for some reason, I don't think I'm willing to deal with the look of a bare body just to save a few pounds. I'm doing this for fun and not flat out competition so creature comforts are still important. So I think I'll put the pieces back in. I can only see a savings of about 20-30 pounds which is negligible in my opinion.

SS RRR

iTrader: (2)

When I first thought about doing relo brackets I read how everyone said it was a good idea to do weld on brackets, so I followed suit. Now that I think about it, I have never heard of anyone having bad experiences with bolt-on brackets. I just like the idea of something that transfers torque to be on a solid mount. You will also have to decide on what final gearing you're going to go with and find a happy medium between straight line and turns. 4.10's could work out fine as long as you aren't topping out in 4th on whatever tracks you run on. Last thing you want to do is shift into overdrive when racing.

Eshaw81

I plan on starting with 4.10s and adjusting from there. Those shoulda been standard on a six speed.

Eshaw81

So, for those of you following along, I have finally decided on a combination of components that work within my budget and my personal goals, as well as with the components I already have. So, here is what im working with...a completely untouched stock LT1 shortblock from my 96 impala which has already been checked out as good. I have a complete LT4 top end including heads that have been pocket ported to 54cc and gasket matched. Also running a 3.750 stroke crank making the block a 377. My goal is to use these components and dedicate most of the budget to the car itself.

So...with the stroker crank, assumed block height of 9.025 and a desire for 12.0:1+ compression and a quench of .035-.040 with the 54cc chambers, I have decided on the following components...

Speed-pro H860CP Hyper pistons which have a dished volume of +5cc
Fel-pro 1094 0.015" thick gaskets
Total seal gapless rings

with the components mentioned above, I should end up with roughly a 12.4:1 compression ratio and a quench of about .037 - .042 which should be ideal. This of course is assuming that the piston maintains the factory measurements and falls somewhere between .022 and .027 in the hole.

This is what I plan to send to get my custom cam made. Of course, I need to build the block first and check how far in the hole the piston actually is. Again, im going with these pistons with the assumption that the block is factory of 9.025.

Did I do this right? Thoughts???

hrcslam

I got 12.47:1 with that combo of parts. With that SCR, you're looking at a fairly large cam no? Wouldn't that force higher RPM?

What I'm seeing is stock resized rods, on a forged crank, with hypereutectic pistons, pushing high compression. I could be off a bit because you are adding displacement, but the cam needed to go with that SCR (even for a stroked LT1), is going to want some top of the PCM limit RPM, which I'm not sure the heads could keep up with very well. I'd be very worried about detonation because none of the parts used in this combo will fair well with ping, even the quench is a bit wide for that set up. Or keep E85 in it.