I already have a brand new HR gasket..if i can find L19 studs, you think with L19 & hr gasket combo it can hold reliable 550hp ? I participate at some track day, have pathfinder mod, external oil cooler, greddy oil pan, gtm stg2 tt kit...

I plan to built with 9.7-9.5:1 wiseco & eagle rod to minimize lag and tuned with 91 octane pump gas.

I know this is not the subject of tread but I have read a few places that 650cc injectors is good for 650hp but other place i read i need bigger like 850cc for the same power?!?! I'm confused (i run with aam rail, stg2 fule return & 255lph walbro) i'll swap walbro for dw or aeromotive pump.

thanks for the hints

 

HR head gasket and HR bolts have been used up to mid 600 hp with no issues. At 550hp I would see no problems running that combination but I would use L19's with the HR gasket if the goal will be over 600hp just to be safe.

650cc injectors won't put out 650hp. A single 255 walbro will max out with somewhere around 700-750cc fuel injectors. Single walbro 255 will run out of fuel anywhere from 500-550hp depending the dyno used. Therefore 650cc injectors will be too small. ID 750's or DW 800's will be needed to get anything over what a single walbro 255 can supply.

 

Agallardo did it when he built his Z...not sure if i still have the pictures..i will look for them when i get home

 

In 2011 that would have been helpful

 

I can't find L19 in Canada but i find it in USA
I'll swap Walbro for Aeromotive and RC650 for DW800 but Osiris can handle 800cc or 1000cc ?

I think i'll sell my HR gasket and get Dynosti just to be sure.

Others suggestion?

 

Osirus can handle anything that your tuner is capable of programming into it.

 

Dynosty gasket has worked great for people so you can't go wrong by using one.

Like stated above, osiris can run any size injector as long as it's tuned properly. They need to be high impedance injectors like DW, RC or ID.

 

I just blew my DE HG. I think I am buying Cometic for the rebuild.

Will there be any issue if I used the HR headbolts? Any mods required to make this work or is just direct fit?

 

If you are going to use HR head bolts then why not use the HR head gasket?
You will benefit from the improved coolant passages (with a minor modification of your block that you can do yourself with a dremel). Also it is very likely the HR gasket is much better than the cometic, having a fire ring to provide additional clamping force on the cylinders.

 

Makes good sense.

I think I'll do that

 

At what power level did you blow?

 

according to hal some time ago the cometics now have stopper ring design as well the major reason he designed his own was quality control issues. also the HR head studs are now having issues due to the tsunami in 2011 and juke head bolts are being recommended by jwt with an additional washer. at that point trying to source extra washers for that setup between time and money i would just say F spend just a little bit extra and go l19 even if its overkill

there was a post just the other week about snapping HR head bolts during normal torquing procedures.

 

Believe it or not, it was just N/A - 270whp approx on Dastek dyno. I've raced the car in hotter conditions though. That could have been one of the reasons why the gasket weakened.

Ok I found the thread, thanks for the heads up bro.

The last post here shows DE vs HR bolt comparison

https://my350z.com/forum/maintenance...defective.html

Looks like Juke head bolt is the way forward

 

One more question:

Is the HR head gasket kit identical to DE gasket kit?

 

no its not the same, thats why you have to modify the DE heads to make it work

 

diff described here:


http://www.jimwolftechnology.com/wol...HEAD_BOLTS.pdf


I am running the HR with L19s.

Note , if you ever rebuild an overbore, you want the also bore out the OEM HR HG to match.

 

Thanks, sirs! Great info. Time for me to go shopping.

 

haven't seen an answer to this in any of my search. Anyone know?

 

So are you asking can you use the HR gaskets with head mod and the pathfinder bypass? Yes, they don't have anything to do with each other.

 

Bringing this thread back again....

I have a DE motor, and HKS gaskets. These are "stopper" gaskets, which I believe means it stops up the large port at the top right in the pictures shown in this thread of the block.

The question I have is....what if I don't machine out the section under it?

I also read in this thread something about a modification to the head, but no information about it.