360 Build

[darten1972]

Hi all. We’ll I’ve asked for advice on a 408 stroker build and now it looks like I’ll need to trim the budget a bit. I’ve found a 87 360 4 barrel our of a 3/4 Ram for a sweet deal. The motor was removed from the truck in great running order not long ago. My question is I plan on doing a complete rebuild on the engine with a rebuild kit from Summit. It ships with Hyperutectic pistons and all the rest to freshen it up. I’ll probably keep the stock 1.88 heads for this year along with my new Air Gap intake and Doug Headers. Can you guys offer me any advice on what parts I should use to build a nice little torque street engine? I have 3:23 sure grip now with a 904/ 2500 stall in a 72 Swinger. A gear change maybe in order as well. Sorry to keep bouncing around but this looks like the direction I’m heading. Stroker will have to wait.

 

[QuickDart360]

3.23 gears are ok but limit cam choice. Going lower gear such as 3.55 and 3.91's would broaden cam choices. Also compression needs to be @ least in the 9's or higher again for better cam types. Just depends on actual use of car street only or strip. Or both.

 

[QuickDart360]

For torque the stock spec 340 cam is good. Also the lunati 268 cam is another good cam.

 

[rumblefish360]

Keep the compression ratio under 10-1. I like 9.5-1 as a max here at sea level and 93 that has 10% corn in and he mix.

Stock 340 cam specs are very broom handle like. The mentioned Lunati is OK. It’s that 3.23 gear. Are you running a stock tire size?

I’ll recommend what seems to be a small cam but will be very good with that gear and a stock size tire.

A cam with no more than 220 intake duration and 6-8*’s more exhaust on a 110 or 108 under .500 lift since you mentioned no head work.

This should peak around 5500. Strong torque from idle to around 4K, it will make about 350 hp.

 

[darten1972]

Keep the compression ratio under 10-1. I like 9.5-1 as a max here at sea level and 93 that has 10% corn in and he mix.

Stock 340 cam specs are very broom handle like. The mentioned Lunati is OK. It’s that 3.23 gear. Are you running a stock tire size?

I’ll recommend what seems to be a small cam but will be very good with that gear and a stock size tire.

A cam with no more than 220 intake duration and 6-8*’s more exhaust on a 110 or 108 under .500 lift since you mentioned no head work.

This should peak around 5500. Strong torque from idle to around 4K, it will make about 350 hp.

Yup 3.23 with 245 60 R15 tire. I’d like to drop to a 3.73 gear maybe just to get things happening a bit quicker. I’d also like to upgrade to adjustable rockers and possibly a roller cam. Any ideas on a roller cam setup?

Thanks

 

[QuickDart360]

A buddy of mine ran the mopar purple cam with 272/455 lift cam in a 318. Thing ran very strong. Very nice torque. This is another good cam. Rumble is correct the stock 340 cam is kind of lame.

 

[QuickDart360]

A buddy of mine ran the mopar purple cam with 272/455 lift cam in a 318. Thing ran very strong. Very nice torque. This is another good cam. Rumble is correct the stock 340 cam is kind of lame.

 

[70aarcuda]

check the kit to see what is the part number on the pistons.

 

[rumblefish360]

A buddy of mine ran the mopar purple cam with 272/455 lift cam in a 318. Thing ran very strong. Very nice torque. This is another good cam. Rumble is correct the stock 340 cam is kind of lame.

IF you can find that cam today for a reasonable price, that would be a good one to run.

Roller cam suggestion?!?!

REALLY?????

Well, let’s back this up a bit! You have left out more than a ton of information and what your willing to do.

I couldn’t possibly recommend a roller cam at this point. HELL! Last cam I just suggested to you was based on assumption of stock tire, trans, converter and no suspension upgrades.

 

[QuickDart360]

Forgot about that! Prices are stupid for mopar cams. What a bummer.

 

[darten1972]

IF you can find that cam today for a reasonable price, that would be a good one to run.

Roller cam suggestion?!?!

REALLY?????

Well, let’s back this up a bit! You have left out more than a ton of information and what your willing to do.

I couldn’t possibly recommend a roller cam at this point. HELL! Last cam I just suggested to you was based on assumption of stock tire, trans, converter and no suspension upgrades.

Ok cool. Sorry I’m no mechanic and I’m still learning. A buddy of mine built a small block with a roller setup and he said he loved it. That cam you suggested is probably right where I should be given the overall build I’m looking to build.

 

[rumblefish360]

Ok cool. Sorry I’m no mechanic and I’m still learning. A buddy of mine built a small block with a roller setup and he said he loved it. That cam you suggested is probably right where I should be given the overall build I’m looking to build.

I have not seen a “small roller cam” suited to what you have gear ratio wise and there expense is outrageous for what your doing. Now! If you were looking to build a nice street stomping MoPar, then I’d recommend something.

On an extra note, I have built a few 360’s. What I myself like to do is use ether the KB-107 or the Federal Mogual Hyper (equal to the KB-107) and have the piston set up to sit at a zero deck height. Use a .050 thick head gasket for a 9.5-1 ratio or a .038 for a 9.8-1 ratio with open chamber d iron heads that have a 72cc chamber.

The higher ratio works well with bigger cams. Later on, if and when you get aluminum heads, this piston and it’s in block placement work really well for a HOT engine set up.

This would also include things like 4.10 or greater gears, big-ish solid and roller style cams. Something making an honest 470 plus HP.

Forgot about that! Prices are stupid for mopar cams. What a bummer.

LMAO! Like I said, “IF” you can find it at a good price. Now that there doing nothing anymore with the sb line, prices have gone nuts-O-crazy.

You can find similar cams elsewhere or have one customized/copied.

 

[darten1972]

I have not seen a “small roller cam” suited to what you have gear ratio wise and there expense is outrageous for what your doing. Now! If you were looking to build a nice street stomping MoPar, then I’d recommend something.

On an extra note, I have built a few 360’s. What I myself like to do is use ether the KB-107 or the Federal Mogual Hyper (equal to the KB-107) and have the piston set up to sit at a zero deck height. Use a .050 thick head gasket for a 9.5-1 ratio or a .038 for a 9.8-1 ratio with open chamber d iron heads that have a 72cc chamber.

The higher ratio works well with bigger cams. Later on, if and when you get aluminum heads, this piston and it’s in block placement work really well for a HOT engine set up.

This would also include things like 4.10 or greater gears, big-ish solid and roller style cams. Something making an honest 470 plus HP.


LMAO! Like I said, “IF” you can find it at a good price. Now that there doing nothing anymore with the sb line, prices have gone nuts-O-crazy.

You can find similar cams elsewhere or have one customized/copied.

Wow great information. Thank you. I’m thinking 3.55 or 3.73 gears to slow me to still take it on the highway at a reasonable cruising rpm. The 3.23 are great for highway but it’s slow getting off the line. I have a 318 in it now that ran 14.4 @ 92 Mph but she was a bit lazy getting going. Let’s face it a genuine lack of torque along with high gear. I figure a nice 360 and a lower gear it should haul this little cars but pretty good.

 

[QuickDart360]

Come to think about some other member on here (don't remember who) said he had Howard's cams custom grind a cam similiar to a purple cam for a fraction of what mopar wants for one! just passing info along so hopefully it can be of help to someone here!!

 

[darten1972]

Come to think about some other member on here (don't remember who) said he had Howard's cams custom grind a cam similiar to a purple cam for a fraction of what mopar wants for one! just passing info along so hopefully it can be of help to someone here!!

Well thank you. Maybe I’ll search for that post.

 

[QuickDart360]

Howards has some existing grinds for mopars that look pretty good to use as they are.

 

[AJ/FormS]

Wow great information. Thank you. I’m thinking 3.55 or 3.73 gears to slow me to still take it on the highway at a reasonable cruising rpm. The 3.23 are great for highway but it’s slow getting off the line. I have a 318 in it now that ran 14.4 @ 92 Mph but she was a bit lazy getting going. Let’s face it a genuine lack of torque along with high gear. I figure a nice 360 and a lower gear it should haul this little cars but pretty good.

A stout 360 like Rumble detailed will pull a 3.23-equipped A-body with a 2800; like you won't believe.I recommend to;Leave the gear selection for last. The zero-deck 360 is a very versatile platform to build on.With hi-flo heads and a 220ishFTH cam, it can sneak into the 12s, while making enough torque to break any street tires loose , that you can fit into the factory tubs, at almost any rpm, in first gear.You ought not to compare it to a 318,lol.
For some extra kick, install some aluminum heads and get the cylinder pressure up around minimum 185 to maximum 200 with a tightQ, with a cam one size bigger. With a little bit of suspension work you could be pulling that 92mph......in the 1/8th now, and the qtr in the low 12s.......... and the 318 will be a foggy, far-off, fast-fading memory.

Happy HotRodding.

 

[rumblefish360]

AJ’s got that right for sure! Choose the rear gear later. Know what your engine is making for power and the cam it is using. Depending on the gear ratio, a stall torque converter may be needed or not. Higher the ratio, the less need for a higher stall converter.

Having run small blocks forever, a cam at 218@.050 duration or less will not need a higher stall converter with 3.23 gears or numerically higher gears.
At 218 or higher, a little stall for the street is good. A 2200-2500 rpm is very good area. At a 3.55 gear, stock tire size or slightly larger, you could get away with a stock converter and a 220 cam pretty good.

The car will be a nice mover.

 

[sireland67]

Throw some KB 107's in it and a comp 262 cam.
It will give you plenty of torque.

 

[nm9stheham]

Can you share details of the Summit kit, like at least the kit PN? My concern is that you will get low compression pistons and thick head gaskets and end up with less than 8:1 static CR, and it will be a bit doggie at low RPM's particularly if you are constrained to keep the stock TC due to budget limitations.

The suggestions of the KB107 pistons made by RF360 and Sireland are spot on but the likelihood that you will get those in a rebuild kit is about nil. I would advise holding off on that kit until more research is done on the pistons. Getting the static CR up in the 9's range is important for what you want to do with this engine: torquey street.

I see the Summit Kit PN CSMHP814-300, which lists hyper pistons, but those look like Sealed Power H405CP's. That will net you an 8.5 SCR at best,(with .028" head gaskets, but no head milling) with stock sized head chambers. (The H405's have a CH of 1.637" and 10 cc's in the valve reliefs.) If that is all your budget will allow (and not the KB107's) then a smaller cam is in order IMHO. But you start off jammed over in a corner of the performance map if you start with low SCR.

If you get a good static CR to start with, then I would expect the gear change will become optional, and only if you wanted to optimize track time.

 

[sireland67]

Summit will adjust any part in their "kits" you just have to ask, but the price changes.
I always piece my stuff together, to ensure I get every part need.
Most of the time the cost is the same or cheaper.

 

[nm9stheham]

Summit will adjust any part in their "kits" you just have to ask, but the price changes.
I always piece my stuff together, to ensure I get every part need.
Most of the time the cost is the same or cheaper.

I agree 100%... try get what is needed to make it right for the application. The last kit I got was for a stone stock /6.

But I also understand budget limits..... it would just be a shame to not put the extra $$$ into the optimum pistons for the job, to cure the typical low SCR of the SBM's, and not get what was really desired out of the engine.

 

[sireland67]

I am getting ready to build another small block.
Been slowly buying parts.
The list always starts out the same.
Complete fel-pro gaskets
Mellings stock volume pump.
Piston depends on what compression I want to run.
Bearings after a trip to the machine shop on crank polish/resize.
Then after everything is back from the machine shop, I will buy an additional set of head gaskets, thickness to hit the exact compression needed to keep the motor alive.
The last two motors, I had to kill compression, so after the motor is assembled, then you buy the cam.

 

[IQ52]

Yup 3.23 with 245 60 R15 tire. I’d like to drop to a 3.73 gear maybe just to get things happening a bit quicker. I’d also like to upgrade to adjustable rockers and possibly a roller cam. Any ideas on a roller cam setup?

Thanks

What might a small hydraulic roller cam do in a 360?

Here is a 360 Magnum with a stock compression rebuilt bottom end, and slightly cleaned up stock Magnum heads, with a 265/273 advertised, 216/224 @ .050", .506"/.506" lift, 114 LSA hydraulic roller cam and using an airgap type dual plane with a carburetor.

RPM.............TQ/HP

2700..........362/186
2900..........365/201
3100..........392/231
3300..........403/253
3500..........414/276
3700..........422/297
3900..........427/317
4100..........427/333
4300..........431/353
4500..........427/366
4700..........428/383
4900..........420/392
5100..........407/395
5300..........396/400
5500..........384/402
5700..........368/399

 

[rumblefish360]

@IQ52 What size carb?

On my wife’s 360, the cam card below in a .030 zero deck slug height, 625 AFB, Edelbrock heads, comp roller rockers, tti headers into a 2-1/2 exhaust, Weiand stealth intake

Whatcha think for power?