I saw a Darton ad in a magazine, and it got me to thinking... Are our engines sleeved at the factory? If we were to install aftermarket forged pistons into aluminum cylinders, we would end up with scored cylinder walls in a New York minute. If our cylinders are lined with life-preserving cast iron already, we're off to the races! Please advise.

'03 G35 5AT Sedan, Garnet Fire/Willow
18x8 SSR GT1/Bridgestone PP S03 225/45/18Y
Eibach Pro-Kit Springs & Anti-Sway Kit
Stillen Cat-Back Dual Exhaust System

 

No need for new sleeves unless you want to increase the bore size. With new pistons all you need to do is hone the cylinder bore because there's a good chance the rings won't seat properly.

2003 G35 Sedan 6MT
14.35 @ 98.62

 

You usually only use sleeves if the block is open deck design im not sure about the VQ35 but top secret's car put out like 800whp on that block so i say its pretty stout fromt the factory the weak link in the engine are the connecting rods which tend to snap after around 450 whp so i would replace those with a set of forged ones from (crower, carillo, pauter, etc) also if you wanna use forced induction above the stock boost from the kit id reccomend gettin sum lower compression forged pistons ( JE, wiseco, arias etc )...8.5:1 or 9:1...

 

You all are talking about something I'd never do, but this thread is a interesting read never the less. Thanks for your posts

"All that's necessary for the forces of evil to win in the world is for enough good men to do nothing.”
Edmund Burke

G35 6mt

 

This is really common thing to do in honda motors since most of em are open deck design. But is unnecessary unless you boost your motor more than 20psi ( more or less) yet still im not sure if it would apply to VQ35 motors like i said before.. it does cost alot of money to do since you have to take your motor out..apart and take it to a machine shop to have the block machined and have the sleeves put in but like bobbyD said you usually do it when you wanna bore the motor out to tha point that exceedes safe thickness of the stock cylinder walls...

 

bullseye,

After looking at the drawings in the shop manual, the engine block appears to be a open deck design without OEM replacement sleeves. Hopefully we don't have aluminum cylinders! Does anyone know for sure?


2003 G35 Sedan - DP / Willow / AT / Premium / Sport
350Z Engine Cover, T-Stat & Air Duct / Stillen CAI
GG 7-Wire H-G Kit / TechnoSquare ECU / E-Fans
Street Edge TC / B&M Cooler / Stillen Exhaust

 

I was almost sure we had OEM cast iron sleeves. Now I do not know what to think. Forged pistons whipping up and down inside bare aluminum cylinders make me cringe.

'03 G35 5AT Sedan, Garnet Fire/Willow
18x8 SSR GT1/Bridgestone PP S03 225/45/18Y
Eibach Pro-Kit Springs & Anti-Sway Kit
Stillen Cat-Back Dual Exhaust System

 

Hmm does anyone have pics of the top of the block ? if so can u post them so we can know for sure? thanks..

 

This motor is open deck and the BLOCK was shown to fail in official nissan tests at about 450 hp. I read this in a magazine with nissan as a source, but have been unable to find siad article since. I'd bet top secret's VQ was either modified to be closed deck, or will fail after minimal use.

 

Here's a picture of Jeff's (at Performance Nissan) 350Z engine block.


2003 G35 Sedan - DP / Willow / AT / Premium / Sport
350Z Engine Cover, T-Stat & Air Duct / Stillen CAI
GG 7-Wire H-G Kit / TechnoSquare ECU / E-Fans
Street Edge TC / B&M Cooler / Stillen Exhaust

181615-VQ35DE Block.JPG

 

Looks sleeved to me.

 

yup it looks open deck to me hmm i dunno if that block would fail at 450hp the cylinder walls look alot beefier than hondas blocks which have some motors putting out 450hp to the wheels without the sleeves but other stockl parts (pistons, rods) propably would tho.. i dont think nebody came out with the sleeves yet but im sure dart could do a custom job..but it would propably cost alot!!!

 

If there was a high enough demand only one thing comes in mind to save money...Group Buy =)

 

There won't be a group buy until Darton gets a hold of a VQ35DE, which they have not been able to do yet...They need to find someone willing to let them test the engine, which in effect means voluntarily sustaining damage

"All the Power in the World resides in the Eyes..."

 

AEBS in San Diego has sleeves and a stroker kit. Heres the link: http://www.aebsracing.com/products.p...ct=vq35stroker