Copper Nine Eight

If im able to get my hands on some old 350 heads, could it be set up for a roller valve train? Or would the money invested be about the same as buying some new edelbrock aluminum heads? The reason i ask is because i read that mating aluminum and cast iron can sometimes cause problem. And i would really like to keep the mechanical fuel pump rather than electric. But i would prefer a roller valve train.

New year resolution is to have my 403 built the way i want and dropped in my 85 Delta! Going to be a interesting year

1970greensupreme

If your asking about roller lifters, it's all the same. Roller rockers, not that much different either. The only slight disadvantage of alum durability wise is if your over-heating, they warp much easier but being alum you can run about 1/2 point higher compression with the same compression ratio due to heat dissipating quicker. I can go on on other advantages but I"m sure you would do some research. I believe edelbrock are only available in 400-455, not small block but can be modified to use on 350 or 403

cutlassefi

You can put roller rockers on just about anything.
But I don’t get the comparison between that and buying aluminum heads, that’s apples to pumpkins.
And there’s probably 500+ million engines out there using cast iron blocks and aluminum heads.

Copper Nine Eight

i read a couple months back that somebody was having a problem mating the aluminum to the cast block (not sure if it was just his mistake or what) but it made me think because i want to put the edelbrock heads because it would be easier than finding a good set of 350 heads to use for my 403 build.
Man! I see your name on here and ROP all the time lol

Copper Nine Eight

Ahhhh ok. Thank green supreme!

cutlassefi

Why not stroke a 350 Block instead of investing in a less than stellar 403?
All Olds heads will interchange, bolt pattern wise. Only the small blocks have fuel pump interference issues, that’s all.

1970greensupreme

I have to send you a pic of my Accel DFI EMIC sticker I got from years ago when I worked for the company that bought DFI from John Meanie back in the early 90's

olds 307 and 403

I agree with Mark on this one. The 403 can be built but with a 4" stroke crank available, you can get more cubes from the much stronger Olds 350 block. I have all the parts for a 403 stroker sitting here, just need a girdle. If I didn't have all the parts and a 403 block taking up space, I would do a 350 stroker. My 403 stroker will be 424 ci, 4.390 bore and 3.5" stroke. The 422 ci build is 4.100" bore and 4" stroke. He can do future overbores with no issue. The best way to do a 403 buid is a rering if possible, early 330 or 350 heads with big valves added, a slight mill for true 9 to 1 compression, depending on the heads cc and probably a cam in the 220 duration range. Cheap and a big power upgrade over your current 307.

cutlassefi

Yep, all gone now. Holley did a real good job of nixing that stuff in a hurry. It was a good system for its time, but I have to admit the new stuff is much better, and faster.
Op, you have lots of options as you can see. That’s a good thing.

1970greensupreme

The originators of DFI still sell stuff under big stuff 3 now. Yes, I agree, things are much easier to tune now but I"m glad I learned on all that older stuff since it makes the new stuff seem like no big deal

Copper Nine Eight

I already have a 403 and space is limited to one engine. And it has to be streetable (going to be my daily driver) and would like to keep the 2004r trans because of limited space.

olds 307 and 403

Another option is port your 4A heads, they need a lot of work, or run BBO iron or Procomp/Edelbrock aluminum heads. Just use KB 6cc hyper or the Arias 3cc forged pistons with the bigger chambered heads. There is a guy who built a 10 to 1 403 with E iron heads running 12's. He also has a T-56 6 speed behind it, in his 87 Cutlass.

Copper Nine Eight

If im going for 400hp, what do you think is best? And working with limited space (cant have too many big things stored in the garage) would it be smart to put a built 2004r behind it or would that be a waste because their would be a chance of it failing. Goal is to have 400hp daily driver with 3.73 gears and a trans that wont fail. Im looking for longevity. I need all the advice i can get. I think i asked this before though lol not sure.

Copper Nine Eight

You guys made me want to try and sell my 403 for a 350 but i remember i was looking for a 350 some time ago and one never showed up. The 403 came along for 200 bucks (bought from gearman69 on here) so i snagged it up.

GEARMAN69

Elliottportworks that does stuff for me could do those 4A heads with bigger 2.07/1.71 $160-170 Ebay set of S/S valves and flow plenty to make that goal. I had him do just basic porting with no polish/sanding for only $200 after I had machine shop cut my #6 heads for the big valves and mine flowed 240/185 enough to go past 450 hp with right combo. Just do that and KM flat tops, headers, RPM intake and a decent dual pattern cam not too big along with the girdle and keep the shifts under 5500 is what would do.

GEARMAN69

Also saw one of the Olds aluminum head vendors on Ebay offering a smaller 64 cc chamber version now. That could be used with the dish stock rebuilder 403 piston and be a good compression too. I do really like the C head build with flat tops shared last year that was strong

GEARMAN69

Your gonna want those cubes for the big car , the torque of the simplest 403 build will be awesome improvement over an anemic 307. I would NOT do 3.73 gears , no need for that much rpm. 3.23 with a TH200-4r Max IMO...

GEARMAN69

Even if you kept it low compression. Like a City Motor Supply or Blaines local rebuilder on your short block with stock piston replacement. The old Comp Cams 275 DEH 219/233 110 cam and the bigger valves with bowl work on the 4A heads, that 68 intake I gave ya and true duals with manifolds would even run real good

GEARMAN69

I still need to come get my engine chain with hook I left...LOL

Copper Nine Eight

Lol! Thanks for info! Im having the hardest time deciding where to for machine work and everything. And the chain is still here sitting on the engine lol!!

olds 307 and 403

As said the 4A heads can be ported but exhaust side is terrible, it will cost more than #6 heads to port. A set of 2.07/1.68 valves would be better and it sounds like German69 has a place they should go. With the KB pistons, that will give 9.5 to 1 compression. With the right cam it will be over 400 ft/lbs which which is really hard on a transmission. A billet forward shaft and drum should be done, a $400 upgrade on the 2004R along with extra frictions in the 3/4, shift kit, servo, quality frictions and a deep pan. A 4L80E is a bullet proof trans with minor upgrades but needs a shift controller, bell housing and speedo adapter and the drive shaft cut. With a short tire I ran 1850 RPM at 60 mph with a 3.42 gear. Here is a good calculator set up for the 2004R with the lock up torque converter in lock up mode. I checked mine with a GPS, very accurate RPM. http://tech.oldsgmail.com/ch_axle.php
By the way, I have a 403 block and a 424 stroker set up for it. It will make good power but the 403's heavy pistons, mine are light(550 gram) with better Scat sbc rods but has the heavier 330 crank, it means a girdle isn't a bad idea if 5000+ rpm is going to happen, thinking 5K max. The 350 with more cubes has a much better bottom end and Mark's new crank weighs less and is stronger than the 330 crank. Add in lighter pistons and stronger, lighter rods and it is a more durable combo.

Copper Nine Eight

I think im going to try to find better heads. I was thinking to go with aluminum heads but now im indecisive. And arent the KB pistons lighter than the stock 403 pistons? Would you match those pistons with stock rods? What rods would you recommend?

olds 307 and 403

Yes, the KB pistons are a few grams lighter. Contact Cutlassefi about his stock replacement rods. Procomp aluminum heads would work awesome. What year and model of a car is this going in?

GEARMAN69

Depends on the timeline for both of us but the temporary motor in my wagon could be available later this year or the #4 heads off of it once the #' one goes back in.


If you can swing the cost of the lighter forged Arias flat tops and the ProComp/Edelbrock heads that is totally the way to go and a upgrade bigger aluminum radiator too.. 450-500+ ft lbs ?? TORQUE will make you HAPPY

olds 307 and 403

A 85 Delta 88 is not a light weight. Does it have the 7.5" rear? If so, you have another big weak spot. A big aluminum rad is a very good idea. The Champion 4 core or their big tow cote or the Griffin 2 core with 1.25" cores for the A body should fit fine.

Copper Nine Eight

You guys never seem to disappoint with the information! You dudes are aces. Thanks! Gearman69 If the heads are available before i save up for my aluminum heads i would buy those from you. Hopefully i save up for the aluminum heads before then lol

GEARMAN69

I think there some good 8.5" B body swaps he can do

GEARMAN69

A 8.5 Posi from a 91-96 Caprice/Impala is supposed to bolt in. That gets you a better 30 spline axle too versus pre 1989 8.5 that had 28 spline. A lot of those Chevy ones are 3.08 Posi and also look at Buick Roadmasters same year but be aware Roadmaster wagons are wider but bolt in. My Dad had one with towing package a 3.23 Posi 30 spline. Some are 2.73 Posi and that's ok since that is still the right 3 series carrier. I would think you have a 2.41 or 2.56 open. A TH350 non lock up with 3.08 Posi 8.5 would be completely viable for great all around hot rod 403 performance too. https://www.gmbbodyforum.com/

olds 307 and 403

I mentioned it, pretty sure my old 81 Delta 88 was 2.41 and a 7.5". Yèah, the newer B bodies are good donor options.

Copper Nine Eight

From the sticker in the trunk, i have a 2.73. I was wondering if i could just swap gears instead of getting a whole carrier from another car.

olds 307 and 403

Should be easy, especially if it is a 8.5", even stock 3.23 gears and 3.42 gears will work. You could get a used ring, pinion and a posi from a used 1/2 ton or B body. If it is a 7.5," get the thick 3.23 or 3.42 aftermarket gears or used gears from a 4th Gen F body with the Zexel Torsen worm gear posi. You would still need 28 spline axles from a 8.5", a dam good idea anyways.

1970greensupreme

Brings back memories, I ordered my mothers 91 Caprice with a 3:08 posi. For a TBI 305, it went pretty well and would knock down 27MPG on the highway with the 700R4

Copper Nine Eight

ahh! Thanks man!

olds 307 and 403

You have a PM.

GEARMAN69

I put a Zexel torsen out of a LS1 F body in my 3.42 95 S10 7.5 rear. it did great and I put a lot of hard miles on it with that 195 hp 4.3 HO V6 even off roading with 30x9.5 tires and a lot of burnouts

Copper Nine Eight

offroading?! Lol nice! Do you know any difference between .The zexel and an Eaton? Im thinking about going the posi route as well.

GEARMAN69

I not would really spend any money on a 7.5 with so many good used inexpensive Pick n Pull yard 8.5 rears nearby that would fit. The old 7.5 Zexel torsen style is worm gear that current Easton 8.5 version now is called True Trac .. The OEM Posi in the B body 8.5 is a Auburn cone style and can be bad or messed up by wrong fluid additives but if can check it and it seems tight , run it. The one in my Dads Roadmaster 3.23 was with like 275000 miles and it worked fine even with weight of wagon on it.

Copper Nine Eight

So i should look for a 8.5 and from there go with 3.23 gears. I probably stick with my 2004r just because of space (Nowhere to put a trans). And get the trans rebuilt because im shooting to be in the 400 range of torque and hp.
im asking so many questions because im making a list of things to do before actually spending money. And this is my first build!
I get help from my dad ( worked on tanks in the Marines)
And my friend across the street (also a mechanic)
And you guys on here and REALOLDSPOWER

olds 307 and 403

Just confirm it is 7.5", I believe both were used in the 80's but maybe it is just wagons. Find a builder who knows the 2004R, the billet forward drum and welded shaft is needed.

Copper Nine Eight

isnt the diff cover different? One has "ears" and the other doesnt? I think i read that somewhere. Gotta find that