400+whp Built Head, Stock Bottomend, 7 Bolt

[BOOSTIN21]

Alright, I am in the market for an AWD 2g, i have a spare 2g head in great shape that i plan on building. I would like to get a bigger turbo preferably a Green or something bigger, like a gt30, or a fp3052, but... i would like to keep the bottomend stock, and i have a few questions on preparing myself and the motor for the power.

1) Lets say the motor has between 75-90k, the compression results test out good, what little things should i look at? Tolerances with the crank/bearings?

2) What kind of head work am i looking at? I checked the surfaces myself with a straight edge and a feeler gauge and it was within factory tolerances. Will a mild port and polish still be a restriction for my HP goal?

3) Now i would like to go with 1mm oversized valves, but i understand that valve work such as a 3 angle valve job isnt as efficient as others. What should i be looking to get done?

4) Should i refresh anything like my water pump just to gaurantee it's in top shape?

5) Will a ported SBR manifold be hurting exhuast flow and choking my engine?

I will be using DSMLink to tune with and i know these bottomends can handle 500whp, i have seen a 1995 TSi AWD tuned to 500whp on a megasquirt, and 1997 GSX hit 411whp with a stock bottomend and FP3065, my buddy is currently running the same set-up.

Thanks any and everything will be a huge help.
Cullen

 

[nanokpsi]

My stock, unopened 2g made 428whp on pump gas. I'm talking stock hg and head bolts. It also did it with 116k on the clock with me driving (not very timid with the accelerator) since it has had 30k. Save the money you wanted to spend on head work and put it towards a non-bolt on turbine housing and exhasut manifold. I use the a cast Rev hard t4that can probably be found for 3-400 bucks, hks 264/272 cams and a 2g magnus. I also run dsmlink to tune. 23psi and 12 deg timing. On good gas it would have made enough to crush the block. I ran a PT67 but similar numbers could easily be had with something smaller.

 

[brute]

Just get the head vatted and vacuum-checked (normal procedure), get the 1mm oversize valves, and 3-angle or 5. The port and polish would be excellent for your setup. It's not even necessary for your goals, so anything extra helps. Replace anything maintenance-wise, so you don't have to worry about it. Belts, pulleys, tensioners, thermostat, upper/lower radiator hoses, etc. The ported SBR manifold should be more than enough.

 

[keymaster]

Remember with 1mm OS valves you're going to lose a lot of bottom-end. Same with most head porting and a SMIM. Totally kills off-boost driving.

 

[brute]

Remember with 1mm OS valves you're going to lose a lot of bottom-end. Same with most head porting and a SMIM. Totally kills off-boost driving.

I've never heard of this. Care to explain?

 

[nanokpsi]

Remember with 1mm OS valves you're going to lose a lot of bottom-end. Same with most head porting and a SMIM. Totally kills off-boost driving.

You might as well add cams to that list as well. As long as you don't go huge with a huge turbo, your low end will never be that bad. Its a 2.0L motor. Out of boost it is never going to have any low end.

I still put my recomendation into a non bolt on. I had a SBR stage 2 ported evo 3 manifold, scm61 and the same HKS 264/272 cams. It took c16 and 28 psi to get it to 400whp.

 

[GVR4592]

I've never heard of this. Care to explain?

The combustion chamber shrouds the valves on the outside edges of the valve enough to hurt performance even with the stock size valves. If you increase the diameter of the valve, the valves become even more shrouded and flow is disrupted. Take a look at a cylinder head with the valves in it from the combustion chamber side, and you'll see what I'm talking about. The only way to correct this is to overbore the block or get a 2.4 block and deshroud the valves by removing material in the combustion chamber. That's why a lot of guys making up to 700whp use stock valves, it's too expensive and time consuming to gain the extra 5-10whp.

 

[DGajre777]

Wow! Not to get off topic, but I always thought that the limit of the stock headgasket and stock head bolts was 400whp.

 

[GVR4592]

That's what I believed for years, because that's what everybody always said. It's not even close to the truth. There have been tests done on the stock head bolts and they are comparable in strength to the ARP's. Most of the problem is how many times they've been reused and their age. The stock gasket has held on 700+whp setups. The MLS gaskets are extremely overrated and if they aren't installed correctly they will perform worse than a stock gasket.

 

[BOOSTIN21]

NANOKPSI-- sweet numbers you got. now to actually go a little cheaper i think i am going to go with just a stock rebuild on the head with some port/polish work and cams. i know this guy in my town who has crazy fab skills and i am getting a SMIM from him at www.throttlebodypower.com. and would a mustang TB be overkill for what i want or should i just get a 1g TB bored? thanks for all the help guys keep it coming.
now out of the few turbos i mentioned which would suit my set-up best?
FP3052
FP3065
FP Green
GT30

any suggestions? i am looking at some borg warner turbos right now

thanks

 

[brute]

The combustion chamber shrouds the valves on the outside edges of the valve enough to hurt performance even with the stock size valves. If you increase the diameter of the valve, the valves become even more shrouded and flow is disrupted. Take a look at a cylinder head with the valves in it from the combustion chamber side, and you'll see what I'm talking about. The only way to correct this is to overbore the block or get a 2.4 block and deshroud the valves by removing material in the combustion chamber. That's why a lot of guys making up to 700whp use stock valves, it's too expensive and time consuming to gain the extra 5-10whp.

Thank you very much. You just changed my mind about a couple things. You

 

[BOOSTIN21]

NANOKPSI-- sweet numbers you got. now to actually go a little cheaper i think i am going to go with just a stock rebuild on the head with some port/polish work and cams. i know this guy in my town who has crazy fab skills and i am getting a SMIM from him at www.throttlebodypower.com. and would a mustang TB be overkill for what i want or should i just get a 1g TB bored? thanks for all the help guys keep it coming.
now out of the few turbos i mentioned which would suit my set-up best?
FP3052
FP3065
FP Green
GT30

any suggestions? i am looking at some borg warner turbos right now

thanks

i got a few more questions here for you guys... really need help with the turbo selection, remember i will be running a ported SBR manifold, so i dont know if housings will work or not and FP's site isnt working for me.

thanks

 

[unlmtdndeavor]

the fp series turbo use a bolt on housing. for response go for the 3052, for top end power go for the 3065.

 

[BOOSTIN21]

well regardless they are both big enough to carry me to where i am shifting let alone redline on a 2.0 motor. its just will the 3065 be abusing my stock bottom end more than the 3052 will?

now what about the TB? COBRA? or... BORED 1G TB?

 

[slipstream808]

The 1g will actually be fine.

BUT if you just wanna go all out, I'd say an ACCUFAB or a Nissan Q45.

 

[BOOSTIN21]

kool thanks

 

[GreddyGst]

I have a stock bottom 7bolt with 119k miles doing 445whp, 25psi, pump gas, on a 30R turbo. Is 500+whp on a dynojet
I don't even have a SMIM yet haha

But my car is back to stock now time to sell it and start a new project

 

[slipstream808]

I have a stock bottom 7bolt with 119k miles doing 445whp, 25psi, pump gas, on a 30R turbo. Is 500+whp on a dynojet
I don't even have a SMIM yet haha

But my car is back to stock now time to sell it and start a new project

That's easily one of the most depressing posts I've read in a while.

 

[BOOSTIN21]

I have a stock bottom 7bolt with 119k miles doing 445whp, 25psi, pump gas, on a 30R turbo. Is 500+whp on a dynojet
I don't even have a SMIM yet haha

But my car is back to stock now time to sell it and start a new project

WOW!! that is impressive, whats your fuel set-up like? what are you tuning with?
man i love the numbers it just sucks that youre selling the car.

 

[elfroggo]

Um, Luis has something bigger planned anyway .

Something that spins all 4 wheels instead of 2