veilside350zTT

Ok guys im doing my short blocks build having trouble deciding if i want to do darton sleeves are not it cost about $2500 extra to have them put in.. My long term goal is to have around 600-700rwhp and run 10sec 1/4mile. Do i really need the sleeves? or should i put the $2500 to something else??

Plans for block are below:
Arias Pistons
Pauter H-Beam rods
Arp (main,rod, and head studs)
Multi-Layer Metal Head Gasket
Clevite or Nissan bearings
knife edge, perp drilled crank
Engine Machining

p.s. for those of you that dont know i have the turbonetics single turbo

Fairlady_z33

iTrader: (56)

Simple as this YES if you dont have the money now it is worth the two extra month wait.

I have heard that several members r having head lift issues passing the 550rwhp mark if im correct.

ReV2Red

iTrader: (9)

Definitaley. I've heard the block itself will only hold until about 600whp before letting go!

dyezak

Besides the extra strength that the sleeves give you (and is much needed in your long term goal) you can also run a much larger bore resulting in a larger engine that would make more power than a non sleved engine. You can run a 100mm bore with Darton sleves wich = 3.8L....that's quite a large displacement bump. Also with a bore that large it unshrouds the valves yielding more flow, and allowing your machinist to rework the combustion chambers to take even more advantage of the larger bore to unshroud the valves even more.

Sleeve's are more than just safety....

dyezak

Here's a pic of a DOHC combustion chamber (not a VQ35, but a good example). Notice how close the valves are to the edge of the combustion chamber. When the bore is increased so much as going to a 100mm bore you can modify the combustion chamber to "unshroud" the valves in that area, allowing more flow.

Dirty Dave

iTrader: (8)

I think shariff has been running more than 600 whp for 20k+ miles without the block letting go. Shariff if you can key in and let us know what your stock sleeves look like now that you have the motor broken down would be appreciated.

ReV2Red

iTrader: (9)

I didn't say it will definitaley let go, only that it will greatly increase the chances of it happening. Yes shariff probably has got about 600 on stock block, but i'm also very sure that he's got it VERY well tuned, which helps immemsely. But i think he's shooting for more power now, so he's going to get the sleeved block. Am i right?

MIAPLAYA

iTrader: (3)

I would say yes. For the simply fact that using 100mm pistons will net you essentially 3.8L of displacement. Well worth it...

Three5oZee

im looking to go down the same road... would anyone deny the results of AEBS... with the 4.3l jump/ stroker kit?... its next years budget... looking to build a beast....advice?, concerns?

nexstage350

iTrader: (3)

sleeve it. do it now what u have it all apart
my 2 cents

ReV2Red

iTrader: (9)

Dont get the AEBS stroker kit. They have to remove small bits of the engine block to fit it, which means to me that it wasn't really designed to well. Also, everybody that has had it, has had nothing but problems with it.

Sharif@Forged

iTrader: (92)

The cylinder walls were fine...measured with a mic. But I still had that periodic head-lift issue when I really pushed it hard. I would say, a welll tuned sub 600whp, with Cometic/Cosworth HG and good head studs should be pretty solid. But above 600whp, I would definately sleeve the block. As mentioned, you can run larger bore pistons, for some free displacement increases. If you arent comfortable with 100mm bore, you could run a 98mm bore size, for roughly 3.65L displacement.

Best of luck.

Sharif@Forged

iTrader: (92)

You are right! Except for the spelling of my name: SHARIF
If I had a dollar for every time it was misspelled.

sentry65

iTrader: (11)

if or when I blow up my engine, I'm planning on doing the darton sleeves with the 3.8 liter bore depending on how reliable it turns out to be as long as it isn't too expensive

ReV2Red

iTrader: (9)

Sorry about that, i've got a friend in the UK with the same name, but spelled with double F, my bad!

veilside350zTT

sharif you said if im not comfortable going with the 100mm bore go with the 98mm... Why would i not be comfortable with this? has anyone ran into any problems doing this?

overZealous1

iTrader: (27)

it could limit future rebuilds. going with the smaller bore will leave you room to rebuild again for a rebore.

Dirty Dave

iTrader: (8)

This periodic head lift your talking about, could it possibly be the stock sleeve shifting in the block ? How did you know this was happening were you burning coolant, oil and did it seal back up after cooling down ? I have a built block without sleeves and wonder if I should be extremely cautious to this happening.

Sharif@Forged

iTrader: (92)

Sleeving helps, but even sleeved blocks are showing signs of head lift past 700whp, so I am making the assumption that head lift is the main culprit. Yes, you should be cautious.

Sharif@Forged

iTrader: (92)

In addition to what Scott mentioned, oversized bores also reduce the effective seating area of the headgasket. Lastly, 100mm bore sizes require a small piston modification, in order to clear the oil squirters. Since the cylinder wall and piston now sit much closer to the squirter, you need to notch the pistons slightly to clear. This is something your machine shop will do, but will charge you extra for.