I have an 85 IROC that has sat most of its life and subsequently has a very leaky motor from all of the dried out gaskets/seals. It is a L-69, T-5, 3.73 geared car so it is peppy, but I would like some more (who doesn't). I don't want to (also can't afford) to put a better tranny and rear in it so huge power isn't needed. It is a toy, not my daily, needing premium gas wouldn't be a big deal.I will be putting Hooker 2460 headers and a good y-pipe on it, changing the open rear to a posi (already have a 94 z-28 SLP take off and the axles for it). Pulling the air/egr system (most of it is messed up already)

I also recently got a 305 from a buddy that started in a 97'ish truck/van that I could use for parts/build/whatever. It has a factory roller cam, dished pistons, 187 heads, edelbrock performer intake, msd streetfire hei dizzy, and a holley 750 dbl pumper( bit overkill).

I want to keep the cost of this rebuild under $600 if possible (have more important things to spend money on)
I can bump the budget up to ~$1000 if needed, What would it gain me over staying cheap?

Option #1 (Cheap) is going to be gaskets/valve seals on the l-69, but otherwise leaving it stock.

option #2 is gaskets/valve seals, xe262 cam, thin head gasket (felpro 1094), new valve springs, and the performer intake? (do i need an adapter for the Q-jet?) on the l-69.

option #3(best power?) is put the roller cam block in and throw the 416 heads on it, performer intake, and a cam (not sure on a preferred roller cam). Will the dished pistons kill the compression enough to not be a viable option? I would also have to buy a fly wheel for this option, has a flex plate currently. Also I've read that this crank doesn't have a pilot bearing, is that something I could add, or does it take a different crank?

Option #4, any other combo I'm not thinking of? any chance I could throw my flat top pistons in the newer motor with just a hone and new rings?

I don't want to have to have machine work done, if I'm going to get that far into it I'll do option #1 to get it driving this year and then wait and do a 350.

I've never dealt with building a motor, so I'm unsure of what direction to go. I have no doubts about being able to do it, just looking for advice on a preferred route to head in

Anything you can tell me about the roller engine? worth building on?

thanks in advance,
Barry






Looks like it was running a bit rich with the 750 holley on it.




















Crank casting number





looks fairly clean





Piston numbers

 

Well honestly, I think your handicapping yourself severely with a $600 budget.
Where else do you want to spend your money?

Cheap and engines don't really mix if you want to do it right. For a small performance build, this will get you 250ish hp and make a fun little cruiser with a bit of a rumble at idle.

1. Use the roller block. (was it running well when pulled?)
2. Use the intake from your 85, it's nearly as good as a performer and doesn't need an adapter for your Qjet.
3. Use the Qjet from your car. The Holley is too big and inferior to the Qjet.
4. This cam: Lunati 20080721LK or equivilent if you prefer comp or Isky or Crane. if you have lifters from the roller block, then have them checked. If they're good, then you only need the cam.
5. You will need new springs for that cam.
6. I know you don't want machine work, but do a valve job and install 1.94 valves and a mild port job.


Have you already done headers and exhaust? You won't realize true power gains until you do headers and 3" exhaust.

But, this will get you started. Hope this helps!

 

Helps a bunch, if I didn't have the roller motor sitting here option #2 would be a no brainer, but having so many options is messing with my head.

Do you think the roller cam will offset the power loss from the dished pistons?

 

you took a picture of everything except the casting number of the block. SHould be on the drivers side rear, you can see it from the top looking "down". Without that I can't tell you anything about the motor.

The L69 was the High performance motor for it's year.


How many miles are on that roller motor? Do you have any idea? Did you see it run? Does he have any videos of it running?

With the cam I listed and the head work I mentioned on the heads, it should more than make up for bit of compression you're losing with whatever pistons those are.

 

Is it your intention to eventually go 350 with this car or do you want to rock out with the 305?

I also recommend these Hooker 2055 headers instead of the 2460's. I know it'll be more expensive, but I recommend getting them ceramic coated...they come that way but are about $200 more expensive.

For your transmission, if it runs fine, unless you start pushing 300hp, you should be ok. If you want to set yourself up for later, then I recommend this 700r4 as a complete transmission. If you do a little bit of work yourself, like install and removal, you can get this Rebuild kit that you can have a local builder put together for you. Total cost runs about $1600 if you do the removal and instal, $2300 for a complete trans already done.

Then, for converters, I recommend going to Precision Industries and getting a Vigilante converter. Dana at probuilt also sells them. An alternative would be Circle -D or Edge converters as well.

 

Block number is 10243878, 96-97 2 bolt main 305. No idea on miles on it, it's gone through a few owners/vehicles since it was originally pulled. No video or for that matter I'm not even sure if the guy I got it from saw it run.

Mildly built 305 is the end result motor for the foreseeable future. Paint, interior, and suspension would all be ahead of even thinking about upping the motor again.

 

I'd probably go a little different route - for your $600 budget I'd do:

Roller engine (assuming everything else checks out)
L30 vortec heads (from a ~97-up pickup/van - cheap at the pick-n-pull - ~$45/ea around here)
small roller cam (i.e. 20080720 vs the larger one listed above - better for small CI engines on the street IMHO - ~$250-275)
Spring setup on the heads to support the cam (i.e. comp setup or LSx style beehive springs and comp retainers, etc - pick one to fit the budget - $80-200)
set of new 'rebuilder' style gaskets and seals ($40)
Steel shim gaskets (i.e. felpro 1094's - .015" compressed thickness ~$50/pr)
cheap knock-off vortec intake manifold ($125-140)

Run your q-jet, tins, etc. from the stock 305. The combo I posted should provide a quick and torquey street engine that's going to give up a tiny bit of 1/4 mile top speed for a lot more "seat of the pants" / stoplight to stoplight fun on a daily basis.

If you sell the remaining parts you might be able to afford to upgrade the exhaust - in that case I'd start with a set of headers since they'll be easier to install while the engine is out and build the exhaust back from there as you can afford it.

 

The car already has a 3" cat back, headers and a y-pipe will be going on during this overhaul, they do not fall under $600 budget.

I can stretch the motor budget to $1000 if needed. If i did what would it gain me over doing a gasket/valve seal refresh and camshaft replacement? What would the next things to do be?

 

Well,

If you go with the roller block, re-use the lifters (they should be good), and get this Lunati Cam 20080720 or equivilent (Comp, Isky, Crane etc) which should work pretty good for your 305, the spring upgrade needed for the new cam, and finally the port/new valves on the heads and you should be golden. All this would go along with the gaskets etc.

If you keep your stock block, get this Lunati Cam 10120702LK
and lifter kit (you will need new lifters with a flat tappet cam, can't reuse the old ones), and the necesseary springs and work done to the heads to accept them along with the 1.94 valves, gasket set and that's money.

In both cases, you keep your intake, CC Carb, Heads (with a bit of work) and accessories.

in the long run, the roller block is "better" but Gm ran flat tappet cams from 1955-1985. Just remember to follow the proper break in procedures for the flat tappet cam.

With labor, depending on how much you do yourself, should be right in the $1000 neighborhood, maybe even a bit less.

 

For $1k I'd probably be looking for a low mileage 97-00 vortec truck 350 engine and then swap a better cam and springs in it and throw a carb intake on it and use your old parts - more HP/TQ than the 305 will give you and it never hurts to have the extra cubes...

 

I would use the roller cam motor, buy yourself some flat top pistons. "0" deck the block. use the "416s"(after a valve job, of course) and get a cam of your choice. it will be a fun little motor

 

Got my car started up and ran a compression test on it today, five cylinders at 170psi, three at 165psi, with 64,000 miles. I'm thinking I'm going to just run the current motor with a complete gasket kit, cam replacement, and the header/y-pipe upgrade.

this is what I'm thinking for parts:
Fel-Pro FS8510PT1 gasket kit
Do I need to upgrade the valve seals that come with this kit to a positive seal type? Or are the included ones ok? Use the head gaskets included or get upgraded thinner ones?

COMP Cams Xtreme Energy Cam and Lifter Kits K12-268-4
Is this going to be to big?
Is it better buying a complete kit like this, or is piecing parts together going to get a better set up? Is it alright to reuse the locks and retainers?

Hooker Competition Headers 2460HKR
Doug's Headers Y-Pipe Kits D901

Sorry for all of the questions, this is new to me and there are so many options. It is a lot to take in.

thanks

 

I wouldn't even pull the heads off - no reason to change out a good set of head gaskets unless you're planning on doing some head work. I'd just change the valve stem seals "in place" with some "positive" type seals (PC seals). With that said I'd go for just a cam change gasket set plus front/rear main seals and an oil pan gasket - should be a little cheaper than the kit with the head gaskets or you can get the better one-piece oil pan gasket.

The cam is a good choice, and would work fine - it's pretty mild so I wouldn't hesitate to run stock retainers and locks with upgraded or "Z28" springs (i.e. Pioneer RV943-X springs) on it - or the kit is a simple way to go and not have to worry about anything.

The exhaust setup looks fine especially if you have to pass emissions and need to hook into a good free-flow cat converter - if not then look into some long tube headers and merging them into a single 3" exhaust or go duals all the way with an X or H pipe.