Is this a reliable build???

[nismo_drifter]

i have a kat running on a t25 and 370cc...

so i was planning on building it a little, money is the problem here...

arias 8.8 to 1 cr and 89.5mm
acl main and rod bearings
cosmetic headgasket and arp head studs
new valve seals
s13 hot cams on intake and exuast

will it be okay to run these lower compression piston or should i just go with 9 to 1 cr...and will my head be able to hold up for 12psi...what else do you guys recommend replacing and why...im still new to this so dont be so harsh, and this is what i have come up with so far...

[jorge1190]

dude u can run 12 psi on a KA with headgasket and headstuds.

[4x4le]

i have a kat running on a t25 and 370cc...

so i was planning on building it a little, money is the problem here...

arias 8.8 to 1 cr and 89.5mm
acl main and rod bearings
cosmetic headgasket and arp head studs
new valve seals
s13 hot cams on intake and exuast

will it be okay to run these lower compression piston or should i just go with 9 to 1 cr...and will my head be able to hold up for 12psi...what else do you guys recommend replacing and why...im still new to this so dont be so harsh, and this is what i have come up with so far...

There is going to be little difference between the 8.8:1cr and 9:1cr.
I dont like acl berings, I like factory nissan ones but thats up to you I guess.
Cometic headgaskes are shit.

[nismo_drifter]

what is the difference going to be in the pistons???also is there is a reason why you like the factory bearings instead of acl???isnt the acl bearing suppose to perform better and last longer???sorry for the noob questions..

[4x4le]

Its probably one of them preferance things. I dunno. Some people like clevite, some acl. I dont like none of it. I trust nissan to keep their clearances in better spec than any of these other companys. Ive also seen allot of cars spin rod berings, I always make it a point to ask what they used. Needless to say I perfer nissan berings. They dont cost much either honestly. Sure, people will spin berings with stock nissan bearings but that is if the engine is still stock, never been opened, or its been a long time since its rebuild. I plan on pulling my engine every few years to "pm" it. Berings/rings/hone/ect. Cheap stuff really and will keep it fresh and new.

[sac]

You are takin the effort to have block machined to 89.5mm
why not step up to the 11mm head studs.. It realistically doesnt cost that much more. And if i was you i would wait till you can buy a stronger set of connecting rods. Sure the factory forged rod holds up ok, But if you go with say the baseline AMS rod you should be good to hold 17psi or so..

and i think bearings is a personal thing.. You just have to make sure they are installed correctly and your good. Just make sure you go OEM nissan with the timing chain.

HERE..
www.ka-t.org :: View topic - How to build a KA24DE (http://www.ka-t.org/forums/viewtopic.php?t=4156)

17psi on a ka is scary fun for the first little while.. like hold your nuts so they dont suck into your stomach scary.. haha..but you get used to it and want more like everything else.

[4x4le]

Ive seen many different types of engines, ranging from honda engines, toyota engines, to sr's and ka's all with great success with cp 9:1 pistons and eagle h beam rods. I went with that bottem end due to that and am very pleased with the result.

[trmn8r]

id stay with lower compression since your running the turbo. you want to also consider machine work for the block. not that you cant do it yourself. but more like an insurance type deal, if the motor so happens to blow you can fall back on the machine shop that did the work. thats my opinion.

[4x4le]

Yea I would love to find a machine shop that will actually build a motor for you so you can turbo it and then actually warrent you on you blowing it up.

[4sfed180]

no one will warranty a "racing" motor. we give the 30/30 warranty. good for 30 seconds of running or 30 feet outside the shop :)

i always use clevite bearings. sometimes acl. cometic gaskets are good. you have to deck the head and block and its perfect. as far as pistons nothing beats mahle. wiseco is good but their pistons dont control extansion as well and need more running clearance. ive used mahle pistons on 4age atlantic motors with about 0.002" wall clearance. most wiseco pistons you have to run at least 3 to 3.5 thou.

[Grimsta]

/\/\ I agree completely. We always use Cometic gaskets, ARP headstuds and Clevite bearings on ALL our builds standard. You would be best off running the 8.8:1 compression pistons for turbo.

[nismo_drifter]

okay so im guessing my head will be fine with s13 hot cams and new valve seals then...im also going to get it resurfaced...

i will just a head gasket from felpro headgasket from autozone, just wondering how much hp or boost can it hold...

as for the bearing i will still be getting acl, i will also be getting eagle rods...and will still be getting the 8.8:1 pistons...

but will i need to get my ecu retuned for the build???since the pistons are lower compression???

[4sfed180]

okay so im guessing my head will be fine with s13 hot cams and new valve seals then...im also going to get it resurfaced...

i will just a head gasket from felpro headgasket from autozone, just wondering how much hp or boost can it hold...

as for the bearing i will still be getting acl, i will also be getting eagle rods...and will still be getting the 8.8:1 pistons...

but will i need to get my ecu retuned for the build???since the pistons are lower compression???

are you building the motor or are you giving all the parts to some shop to do it for you? if i was the shop i wouldnt even use the parts you are providing. eagle is cheap chinese chit that i trust as far as i can throw it, well i can throw a rod quite a ways so that figure of speech doesnt really work but you know what i mean. same goes for fail-pro gaskets.

if you are serious on all your comments i suggest doing some research. you questions have been answered on multiple forums lots of times.

[vvtisupra]

if you are going with forged internals go with the higher compression

[nismo_drifter]

okay so im going to be taking the motor to the shop to install the intermal...

just so that it will be easier for me when you guys post can you guys give me reasons after what you say...and recommend what to use if what i plan on using is chit...just dont post DONT DO THIS and end it there, because thats not really helping me much...thanks guys..

[vvtisupra]

run higher compression to make up for the spool time of the turbo.

[4x4le]

I still say higher compression too. 9:1.
Eagle is not cheap shit. I dont care if it is actually MADE in china, because not everything that comes from china is cheap shit. If that was the truth no ones cell phones, tvs, home phones, computers were typing on ect would work either. I dont care (like I said) if eagle rods are BUILT in america, the specifications they are built to were not chinese engeneered. Eagle is an american company, and all the producs have to pass their quality controll before they are released. I have seen way too many high powered engines hold up well with eagle rods.

Start showing me some eagle rod carnage.

[Grimsta]

You think higher compression makes up for spool time and will make more power because you will have higher compression & Boost, but sorry, it doesnt work like that in the real world. You will have detonation problems. If you go with a lower compression you can use more boost and supercede what you would be able to do with higher compression and less boost. It doesnt take much searching to find that high compression and boost isnt a good combo. Why do you think factory turbocharged cars usually have an 8.5 or so compression ratio.

This is not about if your using forged internals or how strong rods or pistons are, I dont question that, it will be robust, but an engine doesnt run reliably based on its internals. Thats half, its also the tune, and regardless if the worlds strongest rods are in there in your running high comp/boost and dont have the absolute most thorought tuned and sophisticated engine management to keep your engine from blowing up, you will ping and knock when you rev high and your engine will be done for. Your rods will still be intact, but your valves, head and pistons will be chiseled to pieces

[4x4le]

You think higher compression makes up for spool time and will make more power because you will have higher compression & Boost, but sorry, it doesnt work like that in the real world. You will have detonation problems. If you go with a lower compression you can use more boost and supercede what you would be able to do with higher compression and less boost. It doesnt take much searching to find that high compression and boost isnt a good combo. Why do you think factory turbocharged cars usually have an 8.5 or so compression ratio.

This is not about if your using forged internals or how strong rods or pistons are, I dont question that, it will be robust, but an engine doesnt run reliably based on its internals. Thats half, its also the tune, and regardless if the worlds strongest rods are in there in your running high comp/boost and dont have the absolute most thorought tuned and sophisticated engine management to keep your engine from blowing up, you will ping and knock when you rev high and your engine will be done for. Your rods will still be intact, but your valves, head and pistons will be chiseled to pieces

Um, actually higher compression does help make up for spool time. That is the point in having the compression rato higher. Before your making boost the engine is running somewhat naturally asperated, or well with the turbo being a restrictor to the intake air. With higher compression your making more power at the lower rpms which makes your engine accellerate faster getting you into the rpm range where your turbo actually starts working.

Also when I make suggestions, I make them assuming tha someone is actually gong to spend the money and get the car properly tuned. I dont even consider 9:1 compression high for a turbo motor, how is that high? Because its higher than stock? And just because manufracters dont put 9:1 pistons in from the factory dont mean we shouldnt. Is your car all stock? With that mentality I should assume so, yet hope not.

[bmitchell_ga]

You think higher compression makes up for spool time and will make more power because you will have higher compression & Boost, but sorry, it doesnt work like that in the real world. You will have detonation problems. If you go with a lower compression you can use more boost and supercede what you would be able to do with higher compression and less boost. It doesnt take much searching to find that high compression and boost isnt a good combo. Why do you think factory turbocharged cars usually have an 8.5 or so compression ratio.

This is not about if your using forged internals or how strong rods or pistons are, I dont question that, it will be robust, but an engine doesnt run reliably based on its internals. Thats half, its also the tune, and regardless if the worlds strongest rods are in there in your running high comp/boost and dont have the absolute most thorought tuned and sophisticated engine management to keep your engine from blowing up, you will ping and knock when you rev high and your engine will be done for. Your rods will still be intact, but your valves, head and pistons will be chiseled to pieces


They use low compression so when dummies run 87 oct fuel they don't fuck up. Basically they make the engines idiot proof. And we explot that. I have seen countless 10.5 turbo motors. Its all in the tune. Like you said. Also this is useless information to give some one that is going to rebuild there entire motor with forged internals that is planning on using a fail-pro head gasket cause he is having money problems.