planning on ordering 4.75l stroker kit mmr

[Nightmare90gt]

got a few questions before i order.

please i don't want a mmr sucks battle in this thread. if you have a good suggestion then please post.

i have been looking for a while and the cheapest i have found a complete kit balanced is mmr. if you can find me manley pistons, h beam rods, and forged cranks, with rings, bearing, new pick up and frpp oil pump. please post maybe i missed it.

now on to my questions.

1. with the 4.75 stroker will i have to clearance the block. not a deal breaker just like to know what to expect.

2. i am going to assembling this short block myself. i have the reading material but. what else should i do when building this short block?

i have already had the block checked out and it all good.

 

[sleepermobile2]

I recently had a mmr 5.0 stroker motor built. I bought a used short block on this forum, and had it rebuilt. I didn't save any $$ but just didnt have to wait 6 weeks for the short block from mmr. I'd say the mmr stuff if pretty good, its been good to me. All I'd say is a machine shop won't charge all that much to assemble your short block, especially compared to what your spending. I'm not 100 % positive but mine was stock rods with a stroker crank, I don't remember any clearance problems... I've had another stroker motor and it had longer rods, I think that had issues with clearance, and the pistons had a knock. I'm pretty sure you've got the better kit from mmr, I'm much happier with their kit...don't go cheap on the bolts, and consider letting a shop build the short block. Other than that you'll be happy. Also I am not sure if your using a power adder? But next time I build a motor it won't be a stroker...I've built 2 and went backwards on hp both times. I'd go with a stock set up with 10.5 compression .........

 

[Nightmare90gt]

I plan on 10.5 compression and later on putting a procharger on the car. Curious to know how you lost power due to a stroker though. Hard to do unless you drop the compression. I know there's not a lot to gain from the stroker without going big bore but don't have that kind of money and I need an entire rotating assembly anyways

 

[sleepermobile2]

9.5 compression on this motor,but like I said earlier 10.5 next time. The stock motors that were in both my cobras made more power with the blowers. They sure enough blew up or blew apart....... The strokers make less boost !!! They make good torque at low rpms but.....next time I'm going stock stroke 10.0-10.5 comp and all the boost I can get with the biggest blower I can get. Also usually when my motors break, it all breaks. I'd just rather spend the $$$ on boost. You will love your stroker don't take it wrong.

 

[Nightmare90gt]

well in my case it spun 3 rods and the rods ground the crank to far to be turned and it ruined 3 rods i wasn't going to put non forged stuff back in my motor if i'm going threw all this trouble.

 

[sleepermobile2]

You can get used cobra cranks and used manley rods very easily.......I only say that because you asked if there's a better price......I bet you can get a crank and rods for around 500.......just a thought

 

[Nightmare90gt]

yeah i will keep a look out

 

[IUP99snake]

9.5 compression on this motor,but like I said earlier 10.5 next time. The stock motors that were in both my cobras made more power with the blowers. They sure enough blew up or blew apart....... The strokers make less boost !!! They make good torque at low rpms but.....next time I'm going stock stroke 10.0-10.5 comp and all the boost I can get with the biggest blower I can get. Also usually when my motors break, it all breaks. I'd just rather spend the $$$ on boost. You will love your stroker don't take it wrong.

The strokers made less boost because they were flowing more air due to the extra displacement, yet the blower speed was still the same in proportion to the RPM. Boost is simply a measure of restriction, not air flow or power. It's possible to make more power even though it might make less boost after completing a mod that increases air flow. For example, I installed a BBK off road x pipe in place of my 4 cat stocker and I lost 3 pounds of boost but picked up 35 HP on the dyno after it was tuned for the changes. I installed a power pipe and gained those 3 pounds back and picked up another 20 HP.

Turbos on the other hand, would automatically compensate for the added air flow, the waste gate would spin them faster in order to make the same amount of boost.

Also keep in mind that when holding all else constant, an increase in stroke will also increase the compression because the piston travels further in the bore. But the pistons that come with stroker kits take this into consideration and as a result would require a slightly smaller dome than a non stroker piston to achieve the same compression goal.

I don't have any first hand long term experience with stroker motors but I have read that the 5.0 strokers usually don't last any longer than 50K miles and then start burning a lot of oil. This is most likely due to the sacrifices in piston design necessary to keep it in the cylinder during TDC and BDC being that the cylinder is still the same length. The piston pin is moved up higher toward the top of the piston, often into the ring lands, plus the skirts are much shorter so they don't protrude too far down the bottom of the cylinder or worse come into contact with the counterweights on the crank. These sacrifices in piston design affect the longevity of the engine


I have no idea how long the 4.75 stroker lasts, but I'm assuming less compromises are made in the piston design.

If I were to get one of the 5.0 big bore modular blocks, I think this is the rotating assembly I would choose to get a little more displacement instead of the bigger stroker kits that when combined with the 5.0 block bring it up to 5.3L.

Lots of decisions to make.... I want a stroker with high compression.....

 

[na svt]

The amount of stroke added by the 4.75 crank is little and there is no need for any clearancing. A standard stroker is 300ci, the 4.75 is only 288ci, not a big increase in cubes. As for the boost, yes the boost will be a little lower, but if the compression is the same as the previous combo it will make more power with less boost; it's physics, it can't be changed.

 

[Nightmare90gt]

Ordered my rotating assembly I will update this thread with my mmr experience once I check everything out

 

[na svt]

Ordered my rotating assembly I will update this thread with my mmr experience once I check everything out

How much more does stroker kit cost that adds 21cubic inches?

 

[Nightmare90gt]

Like 600+

 

[Nightmare90gt]

My MMR experiance

So I ordered the 4.75l 1000hp stroker kit. It was to include the following.
1. 4.75l stroker crank
2. Manley h beam rods
3. Manley/mmr flat top pistons/wrist pin/locks
4. 4.75l oil pump and pick-up
5. Main and rod bearings
6. Flywheel spacer
7. Timing chain sprocket
8. Fully balanced
9. Total seal piston rings

I received everything except the pick up tube, 8 wrist pin locks and flywheel spacer. Called them the next day they said they will Ship them out that day. Got the package a week later to my surprise the flywheel spacer was still missing from my order. Called again they said sorry and they will ship it out yesterday.

When I first placed the order I asked how long shipping would take they said they would ship it out the end or beginning of the following week. They shipped it in the time frame they said. In all this I have been dealing with Taylor, took awhile for him to get a invoice to make sure things were correct, then when I was cleaning my engine block I found something's that concerned me. I then decided to go 20 over. Called Taylor and he made the change and sent me the invoice the same day. When I received the piston I measured them according to Manley instructions and they were in fact the 20 over pistons.

Another thing that concerned me was there was no paper work showing that my rotating assembly had been balanced called Taylor and be said there should numbers written on my crank box that were the weights of the pistons and rods and I could also tell the crank had a little material taken away.

Over all while I am still waiting on the flywheel spacer, my experience was good felt I got a good price for a fully balanced rotating assembly and the customer service wasn't bad but could have been a little better. They still are standing by there word and getting everything that I ordered.

If you have any questions please ask.

 

[fangs99]

OP, what rings are you getting?

 

[na svt]

I don't think Manley rates their H beams for 1000hp. You may want to give them a call.

Connecting Rod Length Center To Center (in): 5.933 in.
Connecting Rod Beam Style: H-beam
Connecting Rod Material: Forged 4340 steel
Connecting Rod Finish: Shot-peened
Wrist Pin Style: Floating
Clearanced for Stroker: No
Cap Retention Style: Cap screw
Connecting Rod Bolt Brand: ARP
Connecting Rod Bolt Diameter: 3/8 in.
Connecting Rod Bolt Material: 8740 chromemoly steel
Fastener Yield Strength (psi): 160,000 psi
Connecting Rod Bolt Head Style: 12-point
Pressurized Pin Oiling: No
Approximate Connecting Rod Weight (g): 602
Big End Bore Diameter (in): 2.239 in.
Pin End Bore Diameter (in): 0.867 in.
Advertised Horsepower Rating (hp): 700 hp
Advertised RPM Rating: 7,500 rpm

 

[fangs99]

I think the rods are very under rated.

 

[GCubersoldat]

Very bad personal experience with MMR, I would look elsewhere. Stroker kit I ordered needed the block to be clearanced when their description explicitly said it Didnt. Called them up and they told me "too bad, sorry" among a shit storm of other things.

Great alternatives are brenspeed or local shops that have built good reputations.

 

[na svt]

I think the rods are very under rated.

I trust Manley's rating and would not run an H beam at the powerlevel.

 

[Nightmare90gt]

Very bad personal experience with MMR, I would look elsewhere. Stroker kit I ordered needed the block to be clearanced when their description explicitly said it Didnt. Called them up and they told me "too bad, sorry" among a shit storm of other things.

Great alternatives are brenspeed or local shops that have built good reputations.

Read your thread before I ordered. Nothing against you but you have expected the unexpected no matter what there site says. Not saying it's your fault at all but I went into this thinking I would have to cleance the block. Please don't turn this into the thread your became

 

[Nightmare90gt]

I trust Manley's rating and would not run an H beam at the powerlevel.

I don't ever plan on going over 500hp anyway.