Ok guys, I lost a bearing or a oil pump with the Caprice LG4. I'm done throwing money at the motor. Particularly if its the bearing. So I'm thinking, I have the L69 block, cam, some lifters and the oil filter mount. Why not take the L69 and build a 300 Horse motor. Now, I've read around the boards for the past several hours. But most of them are years old. So I was wondering what was still out there, or what has come out since that is new.

Now, I intend to keep the T5 and stock 3.73 gear ten bolt. I know I might have a problem with the trans, but lets ignore that for now (drive it til it breaks mentality or I'll build the trans too). The reason I'm going for 300 HP is, I want to see in theory anyway what a TTA can do with a stick and some 3.73s. We all know the 250 HP rating is BS and its reportedly gotten 300 on PAS's dyno back then.

I can see at least running TTA numbers as I've got a slightly lighter car and the gears help too. Any car that runs depending who you talk to or read 4.5-5.1 sec to 60 is fast enough for my purposes anyway for now. So, here is what I might do.

Keep the CC Qjet as several have stated that it can handle it once its tuned right.

Rebuild the bottom of the L69 with all new pistons crank etc. Possibly stroke it?

Heads I don't know what is out there but will L98 or LT1 heads bolt onto a L69 block, yet retain the ability to run a carb intake and CC Qjet.

Keep as much of the original parts as possible as far as the accessories go, with a possible underdrive pulley.

Headers, and maybe Dual exhaust, if not the 3 inch custom with an L98 Y. I'm running QQ plates (NJ Historic Plates) so no emissions testing.

I'm saving up for the build up but I want to know whats out there so I can balance my ordering with my finances. Get all the parts then either I'll build it myself in the garage, or I'll have it all sent out and have the engine builder put it together.

And PLEASE, NO 350, or 383 swap claims. I've looked at doing it myself. But I don't have the money to go upgrade my trans, and rear as well as the motor all at once. I want to have a car that is plenty fast, but will at least last for a while if I am easy on it, and maybe a couple runs down the strip.

Edit: Forgot to say that I'm thinking of changing the cam and possibly a three angle valve job too. Finally it must run on Pump gas, I don't care if I need to run 93 octane but if I can avoid it all the better.

Thanks guys

 

If you wanna really hop up an L69, this is how I would do it. Dunno if it would make 300hp, but it would get close. I'll just assume the shortblock is in good shape here.

- Comp XE268 camshaft and matching springs/lifters
- Rebuild stock #416 heads with 1.94/1.60 valves, screw-in studs, guideplates, valve guides machined to handle more lift. Have heads shaved to be able to make 10:1 or so with stock pistons.
- Hooker 2055 headers and matching Y-pipe. 3" catback of your choice.
- Performer RPM (Qjet version) intake manifold
- Tune carb and ignition to suit the build.

This (or other similar) combo should make some pretty good power, and still be pretty streetable with a manual transmission. It will want to rev though.

 

if your looking into stroking the motor powerhouse makes a nice 335ci stroker kit that comes with new pistons crank bears etc. Ive thought of stroking the L69 in my 15th t/a but chose against it because that along will cost about 1500 with the machine work... just an idea for ya

 

Lets say I just stroke it and keep the rest of it stock except for the headers and exhaust, what will that give me? Its already got a 9.5:1 compression.

 

well i do know that the kit along takes compression to 10:1, but i have been doing research for awhile and have not gotten any definite answers on horsepower gains, ive found numbers up close to 300 horse and some state that the stroker kit by itself is minimal. I know there are a couple of people on this forum that have completed the 335 stroker kit, hopefully they will chime in.

 

Hopefully they do. Right now I'm leaning towards something along the lines of doing something like that. Thing about going 350 or bigger is you've got all that torque and its bound to rip apart the T5. If I stick with the smaller motor you still have the torque but, ideally it just might last a lil longer. I'm gonna talk to a guy I met from the NJFBOA boards and get some better numbers on what it would cost to do something for power. But in the meantime, keep the ideas coming.

 

I found a guy (Tunedport335 on one of the IROC boards, might be here too) ran 13.41 with his with a 2.73 gear set. Now say I used his setup but instead of using the TPI, I used the Q jet. With my 3.73 set in the rear I'll be screaming everywhere I go. Since I have no crank, pistons, rods, etc. It might be worth it to go with the stroker in my case. Ofc, the dark side of this is it will cost me in machine work.

 

If you don't have enough money for a 350, you certainly can't afford a stroked 305.

 

Oh I'll have the money to do either way, what I meant was to upgrade everything along with the 350, as I stated before I don't want to have all that torque with the 350 blow the trans and rear within 100 miles. I'm thinking of keeping the 305 because of the theoretical lower torque figures. If I do upgrade the 305 I'll probably just stick with the heads, cam, etc mods. Rebuild the bottom end stock so I'm not spending a fortune on machining the block to stroke the 305. I need everything anyway.

 

Machining for a 3.75" stroke crank is a matter of hand grinding the pan rail for rod clearance. It's the least of the expense. Machining for a stock rebuild will otherwise cost the same as machining for a stroker crank. Other than the stroker crank and pistons, all of the other "rebuild" parts would cost the same.

Spending good money on rebuilding a 305 bottom end just doesn't make sense. For $50-$150 more for a rebuildable core, you can do the same with a 350. Everything that would have to be upgraded for a 350 would have to be upgraded for a healthy 305.

Start with the 350 now, don't beat on un-upgraded parts, you'll be positioned for future upgrades when funds allow.

On the other hand, spend money rebuilding a 305 bottom end now, that's just that much less money you'll have for achieving your end goals, and which you'll have to spend again in the future.

If you want to save money now, I'll bet you could find a member (or others) that would give you - GIVE you - a serviceable 305 short block that you could do cam/heads/intake/exhaust on now.

 

You do bring up a good point. Maybe I'll just keep the 305 parts for now as well as the block in case (unlikely) numbers matching means anything on these cars. Another reason to keep them is in case I decide to restore it to factory showroom condition. So, I guess I'll have my fun for now with the 350, and roll the dice on the trans and rear. At least if the trans blows its not a bad swap to bolt in a T5 WC. People have made the argument that unless I'm going drag racing, the ten bolt should last if I don't dump the clutch too often. Which considering the cost of tires is kind of pointless.

 

www.hioutput.com/tech/400hp/400hp.html I have this same build.It may be old school but it is one powerful 305.

 

That power chart in the dyno test section, explains why I want to keep the 305. Has lower torque numbers than the 350, and in theory easier on the rest of the drivetrain. Maybe what I'll do is, I'll take the 305 block to the builder, have him look at it. Take the spec chart from that site and hand that to him. I'm not going for 400 horses but who cares. Then ask him for a comparable 350 build power wise. After he gives me those numbers, I'll ask him 350 and 300-310 horse numbers too. Chances are I'll end up going with the 350. But I'm exploring all options. It will be a while before I build the motor anyway. I'm doing the brakes and suspension first, back to stock. (already has WS6 so...) Then I'm gonna deal with the motor, and if I have the money the trans. I'm not doing the rear yet. I'm taking a drive it til it breaks mentality there.