possible 360 roller buildup?

[hujibwa666]

I have an 86 fifth avenue with about 140,000 miles on the original motor, a roller cam 318. I've heard a lot of people say building up a 318 is a waste because it's the same cost to build a 360. So, assuming I can find one, thats the route i'll go. But I got to thinking... I could probably use a lot of parts from my 318. It has the desireable high compression "swirl port" heads, I could put those on the 360. It also has a roller cam. I was thinking maybe I could use the hardware with a new cam on the new motor. Is this even worth it? I looked up a stock replacement cam, it was $370! Are there cheaper aftermarket roller cams out there? So... hi compression swirl port headed roller cam 360 with a dual plane 4bbl. How does that sound?

[Firelord]

In a nutshell

Yes, many parts from the 318 will fit a 360. Crankshaft and oil pan will not as will many other parts. Also 318 heads have smaller ports which is not good on a 360. I wouldn't put those heads on. You may be able to get away with it if you do some good porting, but porting is usually expensive.

Aftermarket cams are avilable much cheaper. Do yourself a favor and visit summitracing.com

Also, it is going to take a lot of HP to make a car that big move fast. You have to consider if you build the motor up too much you may end up blowing the tranny or differential.

Anyway, happy tinkering.

[hujibwa666]

Most fifths come with a weak, high geared axle. It's only 1 wheel drive anyway, so I intended on replacing that before I did any major engine work. It has a new tranny, but it's a 904, so I figure that wont last long behind a nice motor. I intended on beefing up the rest of the cars drivetrain before swapping engines. I know the car is big, so I don't expect it to go insanely fast. I want my motor to have a lot of torque, and i'll gear it lower if I get a chance. It wont see anything higher than 80mph, so i'm not too worried about top end.

[jimbo7074]

I think a roller cam 360 would be quite good if you replace the cam with something a little larger.As for the 318 heads, if you ported them and added bigger 360 size valves, they would work on a street motor, if you aren't looking for more than 5500RPM.These heads would also raise the 360 compression quite a bit,so you would want to work that out.

[Firelord]

Hold on to the 904 if you aren't tweaking too much. There's a few guys out there with 904's behind 340's. If the tranny is new wait until you blow it before changing it. Unless, of course, you have a good buyer for the 904. I agree with hujibwa; if you change the valves and do some porting it should work; although I'm not sure if a 2.02 will fit on that head. You also got to think about springs if you go above , say.450, lift. Compression with stock pistons should be okay at around 8.7 (my 360 is stock 8.4 with 65 cc chambers. That head has 62.6cc; of courese these are book specs and you are better off cc'ing.

[DartGT66]

There is a hassle involved with the factory rollers. The lifterbores are higher than in the earlier flat tappet blocks, and the lifter alignment is handled by a gridle that attaches to the lifter valley, the non roller blocks do not have these attaching points. If you already have it, I would just build the 318. CR up to around 9.5:1 , big valves & pocket porting to the heads, a mild performance cam, a four barrell intake & carbin the 600 cfm range and free flowing exhaust,possibly with headers, and you'll have a well performing package.

[bbeep71]

Hi,
I also just bought a 1988 318 with roller lifters and 302 heads. who make a roller cam that works with this engine without lean burn or computer control? I don't see roller cams listed for this engine, unless engine is retro fitted with rollers in non roller engine.
Thanks
bbeep71

[DartGT66]

Would believe, that magnum grinds could work in a LA too.

[5th_Ave_Sleeper]

you can use any hyd type cam in an engine with roller lifters. although you wont be using all of the advantage that the lifters cangive you. You dont have to buy one of those $300.00 "roller"cams just because you have roller lifters,
I am currently swapping a 360 into my 86 5th Ave. I have upgraded the tranny to a 727 and the rear to a 8.25" w/3.55:1.
My 360 has been punched .060 over(ouch) filled it with 10.5:1 pistons. and put a MP 292dur/ .509lift cam in it. my heads are ported alot. I took a few pounds off each head I think. 2.02/1.60 int/exh valves and milled .050". I think that will get my leather interior luxo-barge to scoot pretty good.
Im not saying you have to do all this to get a 5th to go fast. I have been told by the guys at Hensley racing, that to make a "strong" 318 you simply find a set of 360 heads, mill them @.040", 3 angle valve job, a 340 stock cam, headers and an M1 intake and your set. Just because its a 318, doesnt mean its a dog. they are just emmision controlled to death!
5th.

[DartGT66]

That is not true. First, the cam profiles are very different because the roller touches the cam only from the center of the lifter bore. Using a flat tappet grind with a roller lifter would make the ramps very slow compared to a regular flat tappet lifter. Second, because of the very narrow contact pad of the roller lifter the surface pressure is too big for a regular hydraulic cam. Third, flat tappet cams have a taper on the lobe to rotate the lifter; with a roller lifter it would only touch one edge of the lobe putting even more strees on the cam. It's simply a no can do, the roller cams cost more and there is a reason for it.

[5th_Ave_Sleeper]

I didny realize that it was than involved. Im glad you threw that post out there, cause I would have tried it. not now, thanks for the enlightenment, Dart. I guess its another case of "they gotchya by the balls"
5th