nismofreak1208

iTrader: (30)

I'm currently at a loss as to whether a longblock or shortblock would be needed for the GTM HR TT stg 1 kit, Funds are accessible but tight, but i've only found information on the de and rev up motors, very little to none on the benefits of the HR motor other than GTM's thread where they used a stock block and clutch. I'm looking for info by other fellow TT HR owners to help make this build a first time go, shop time can get pretty expensive and i'd really like to get the build done right the first time. But mainly my question is as stated above, whether or not i need a built block and if so, do i go for a short or long? and also how have other HR TT owners been doing since they started boosting.


edit, i plan to push 520whp daily driving and auto-x events

MDHRZ

iTrader: (14)

If you are only looking for 520whp then why build the block? Keep the stock block and you can have 500whp. There's one member on here that is pushing 515whp on the stock block without any issues (that I know of).

ttg35fort

iTrader: (2)

At 520 whp, a stock block may not hold up that long - some have better luck than others. Part of that may be that some guys take it easy on the motor most of the time, and some guys push it hard most of the time. It also may be luck of the draw on the particular stock block.

Considering how much money you are going to be dropping on the turbo kit and install (or time if you install it yourself), if you are the type of guy who is going to push that motor hard, you might as well put in a built short block with rods and pistons that are actually designed to handle the hp levels you will be running. Now, if you are the kind of guy who just likes the thought of 520 whp, but won't fully use it all that often, then you might be OK sticking with the stock block.

nismofreak1208

iTrader: (30)

so that means i should only spend on a fully built short block? cuz thats the other part thats unclear for me, will a short block suffice or just go ahead and grab a long block?

Vas_Z33

iTrader: (39)

you will be fine with a short block. no reason to run a long block ( heads and cams ) unless you reallyy wanna put some serious power. stay with stock heads and get a built short block and enjoy the power.

ttg35fort

iTrader: (2)

^^^^
+1

The stock heads are fine. I think the stock cams will even get you to 520 whp. Of course, aftermarket cams will allow you to rev higher before the power falls off. There are a number of cams to choose from if you want to go that direction. Talk to your tuner/builder about your goals and see what they recommend.

Goo$e

iTrader: (9)

I was in the same boat as you. Everything you said above is what I was on the fence about. I'm doing STG 2 with SnowP STG 2 and not building anything. I didn't have the extra funds to do a fully built short block...it would have been nice too just for extra security. Sam told me it will hold up fine no issues. If I do have issues down the road I'll just do the short block (been putting extra money aside just incase).

dikspiel

iTrader: (70)

If you have the funds get a long block and lower the compression. At least you will have some peace of mind that your engine is boosted safely and conservatively.

ttg35fort

iTrader: (2)

Some people are having good luck with the stock block, but some are not:

https://my350z.com/forum/forced-indu...hr-engine.html

A built short block is certainly adequate for 520 whp (get the appropriate compression ratio for FI), though cams/springs would be nice. If the OP wants to rev higher, Ferrea valves would be icing on the cake.

Spending a lot of money on head work just is not worth it for this hp range, though. If I remember correctly, Tom000001 is still running stock heads/valves, and he is getting serious hp. I think he does have BC cams (or maybe he was talking about going to BC cams, I don't remember).

Tom, do you care to provide some specifics on your build and/or opinion on using stock heads?

Goo$e

iTrader: (9)

Yes I saw that thread when it was made.

ttg35fort

iTrader: (2)

Please share the details...

Goo$e

iTrader: (9)

^^^ lol, you quoted my post before I could edit that out. Made a mistake. I was thinking of a different person. There was someone on there where they were in a rush and they took the car without it be fully like tuned to perfection. So something happened down the road on and blah blah.

ttg35fort

iTrader: (2)

^^^^

Here it is very simply: If you take a stock block and push it to 520 whp, that is roughly 580-590 crank hp. That is nearly double the design specifications of the VQ35HR. Sure, Nissan designs in a safety margin, but that safety margin is to ensure longevity. When you start to push a motor at nearly twice its rated output, you are taking a risk that something is going to fail prematurely. Moreover, the VQ35HR was designed to be N/A, and has a corresponding compression ratio, 10.6:1 I believe. At 520 whp that motor will be running on the edge. There is no margin for error and if/when something does go wrong, the motor may fail. Some of the VQ35DE guys get a lot of miles at 400+ whp, while some don't. That is a fact. Over time, I think that we will see the same thing with the HR motor. Some will hold up for a reasonable amount of time at 500+ whp, while some will not. Considering a built short block with pistons and rods designed to take the hp, and that has a compression ratio selected for FI, is relatively minor expense in comparison to the overall cost of the build (5%-20% depending on the build), it adds a nice comfort of margin for those who do not want to deal with an unexpected engine failure. If the car is a second car and the owner can deal with an engine failure without really fealing a burden, and they want to save the cost of the short block, then to them it may be worth the risk. The cost alone of swapping out the motor/turbo system, though, often comes close to the cost of just using the proper short block up front, not to mention the cost of the replacement short block.

Goo$e

iTrader: (9)

^ I agree. If I had the money I would have done a short block. Also it depends the driver as well. If you got someone that smashes on their car vs. someone who doesn't that has the same thing done. Obviously the person that smashes on their car is the car that will break sooner.

midz350

iTrader: (4)

I think the STG 2 kit would be more adequate for the built block.

MDHRZ

iTrader: (14)

I think the big mistake there was that he was riding around on a GTM reflash that was included with the "turn key" kit. It may have lasted longer if tuned properly .

nismofreak1208

iTrader: (30)

hey vas z33, i was wondering what kind of canards and eyelids you have, as for the other posts, thank you everyone, its really cleared up now on which block to get, now i just need to decide which shortblock to buy prior to my build, but i heard tho that if you get cam's, it'll only be beneficial for those who drag rather than those who auto-x, is this true?

midz350

iTrader: (4)

you think??

MDHRZ

iTrader: (14)

Yea, I think.

Goo$e

iTrader: (9)

LOL midz350!!! but I thought your HR failure was not due to ECU right? There was a different guy that like took his car from GTM without it being tuned to perfection. GTM was not comfortable at all with this but the guy insisted taking it anyways. Then down the road there was smoke and stuff and blah blah

That wasn't you or was it? I'm getting ppl confused up in here yo.