Reasonable Power Goal?

[JayB12]

What's a reasonable goal to shoot for if I plan to keep my 7bolt as long as I can?

I really wanted to get an 8 Blade Hx35 with the twin scroll housing/mani and try to see where 20-24 psi gets me.

Engine Spec's:
-120k 7bolt motor (re-ringed and new bearings at 80k)
-Stock Rebuild Head @ 80k
-ARP Headbolts on OEM composite

Is it reasonable? Or do you think it's pushing it? I know there are 500+ whp 7bolts but this will be DD.

Question is,is this practical? will my block be able to take the stress being DD? I rarely drive with a heavy foot so it won't see too much abuse.

I just want a little assurance that if I bump up the boost I'm not going to blow a rod through the block.

Also, I'm currently running a 16g. Close to maxing 550s at 16psi, I don't know if it's even worth going bigger if my block can't take it.

 

[importracr317]

Pushing it IMHO. And if you're maxing out your injector duty cycle on a 16G, you need to get bigger injectors before you think about buying a turbo with the flow capacity of the hx35. That turbo at those boost levels grossly exceeds the flow potential of the 16G.

Regarding power.... and this is just for sh*ts and giggles and in no way an endorsement or a recommendation for the power capacity of a stock block 7 bolt....Adam D from Devo (Chicago area DSM/EVO/rally shop) told me (a long, LONG time ago), the most power he'd ever on a stock 7 bolt was 550-ish whp at 30+psi....it held together for 2 dyno runs, then exploded.

I'd suggest squeezing as much power out of the 16G as possible. Upgrade your fuel capacity, make sure your motor is in shape (120K miles, I'd need more than new rings and bearings to get comfortable), make sure you have appropriate tuning tools, then start thinking about a bigger turbo. You'd be surprised how much fun a 300whp 16G powered car can be.

 

[josh1095]

300whp is alot...... when you are hauling around 2700lbs!! these cars are featherweights. im shooting for 350 with a build that could handle 600. 350 is gonna smoke most everything around here in a go-kart of a car like the dsm. just be reasonable. your engine has a few miles on it, your HG is composite, internals not forged and all your main,rod,etc. bearings have 120k on them. keep all that in mind. maybe go for 300 now then when time and money permits, have the engine torn down and rebuilt to handle all you want. my .02 bro

 

[dsm-man]

Upgrade your fuel system and run e85 on that 16g and youll be moving that dsm along trust me

 

[bastarddsm]

I really wanted to get an 8 Blade Hx35 with the twin scroll housing/mani and try to see where 20-24 psi gets me.


Is it reasonable? Or do you think it's pushing it? I know there are 500+ whp 7bolts but this will be DD.

Question is,is this practical? will my block be able to take the stress being DD? I rarely drive with a heavy foot so it won't see too much abuse.

I just want a little assurance that if I bump up the boost I'm not going to blow a rod through the block.

Your not going to get anywhere near 500whp on 24psi on that turbo. You might see 450 on E85 if the rest of your setup is kick ass. On 93oct, expect about 400whp.

I'd also skip the twin scroll. In a fwd all that will get you is a bunch of wheel spin.

Also a 120k 4g is living on borowed time as it is. Don't expect it to go another 100k miles while making 400whp. It could live at 400whp, but a few detonation events could easily window the block.

Don't expect any assurance, hell it seems most people can't even get a built motor to live at decent power.

 

[clipto]

You will only see like anywhere from 250-280whp on a 16g and your setup as is wit just some more boost and fuel.

 

[Calan]

You will only see like anywhere from 250-280whp on a 16g and your setup as is wit just some more boost and fuel.

If he runs more boost and fuel, why would he be limited to 280whp?

 

[clipto]

If he runs more boost and fuel, why would he be limited to 280whp?

Pump gas. This is my theory of course after dynoing my 16g so many times I am about the limit of it on pump gas on 19-20psi, tho he is fwd too and also he has a 5 speed and not an auto like me so I am sure he could be in the 300whp range but will find out soon he will be maxed out at about this horsepower range.Of course there are always other fuels to run like 25psi but I have set the 16g at 25 psi on E85 and it fell to 22 psi but give or take it was still not the best number all revolving around 300-350whp range.Hopefuly I didn't throw to much confusing as we are talkin about his current profile mod list?It is less then mine and I am at 300whp on 19-20psi so that's where I got my numbers.But if talkin about the hx35 at about 20psi is going to be not much higher then the 16g imo maybe like 400hp w/ supporting mods like bigger fuel pump and injectors, but I wouldn't run that if he wants to keep the longitivity of his 7 bolt.Every car is different I am sure if you wanna run a hx35 just get a 255 fuel pump and 1000cc injectors with link and tune till you don't get knock then come back and tell us how much power you will make I am sure you will be fine.Also I was lookin at your profile not sure if the act 2100 will hold up if make that more power maybe look into a 2600 I think they are good for 450hp and the 2100 is like 350.

 

[Calan]

Pump gas. This is my theory of course after dynoing my 16g so many times I am about the limit of it on pump gas on 19-20psi, tho he is fwd too and also he has a 5 speed and not an auto like me so I am sure he could be in the 300whp range but will find out soon he will be maxed out at about this horsepower range.Of course there are always other fuels to run like 25psi but I have set the 16g at 25 psi on E85 and it fell to 22 psi but give or take it was still not the best number all revolving around 300-350whp range.Hopefuly I didn't throw to much confusing as we are talkin about his current profile mod list?It is less then mine and I am at 300whp on 19-20psi so that's where I got my numbers.But if talkin about the hx35 at about 20psi is going to be not much higher then the 16g imo maybe like 400hp w/ supporting mods like bigger fuel pump and injectors, but I wouldn't run that if he wants to keep the longitivity of his 7 bolt.Every car is different I am sure if you wanna run a hx35 just get a 255 fuel pump and 1000cc injectors with link and tune till you don't get knock then come back and tell us how much power you will make I am sure you will be fine.Also I was lookin at your profile not sure if the act 2100 will hold up if make that more power maybe look into a 2600 I think they are good for 450hp and the 2100 is like 350.

Yeah, but...um...I don't... what?

Please put down the bong, step away from the keyboard, and go eat some Cheetos or something.

 

[purplerocket69]

Go for about 300. The goal for my 420A build is 350 but about 210 N/A and then when it's time for a turbo, about 320 hopefully. Mines FWD 5 speed.

 

[clipto]

Yeah, but...um...I don't... what?

Please put down the bong, step away from the keyboard, and go eat some Cheetos or something.

I don' smoke...All I was saying is he will be close to 300hp with his current setup and if wanted to run a hx35 he should be able to produce good number above 300whp...

 

[boostednavyac]

I'm in a similar boat as you JayB12, i just purchased a high mileage 7bolt GST w/ a 16g and am considering upgrading but i believe ill stick to the quick spool, simple, modest 16g at 18-20lbs and just shy of 300whp DD and call it a day

 

[clipto]

I have noticed alot of people are trying to make the same 300hp goal latley and it's rather simple.I made 300whp with my fwd auto 95 talon I got 113,000 miles now on a stock motor and just had a 255 fuel pump, 550cc injectors and a safc when I first made this horsepower with a small 16g at like 19psi.Granite I had an exhaust but what I only spend like $500 bucks for everything.It's rather simple everyone seems to make it confusing and that's the only reason I think people ask the question to much or they just arent looking.

 

[boostednavyac]

I have noticed alot of people are trying to make the same 300hp goal latley and it's rather simple.I made 300whp with my fwd auto 95 talon I got 113,000 miles now on a stock motor and just had a 255 fuel pump, 550cc injectors and a safc when I first made this horsepower with a small 16g at like 19psi.Granite I had an exhaust but what I only spend like $500 bucks for everything.It's rather simple everyone seems to make it confusing and that's the only reason I think people ask the question to much or they just arent looking.

I completely agree, im basically doing exactly that route and i'm 90% there. for some odd reason the previous owner had a 255 pump but not AFPR, im gonna get that, get a better tune, replace the stock exhaust, get a FMIC, up the boost and should have around my 300 goal

 

[clipto]

I completely agree, im basically doing exactly that route and i'm 90% there. for some odd reason the previous owner had a 255 pump but not AFPR, im gonna get that, get a better tune, replace the stock exhaust, get a FMIC, up the boost and should have around my 300 goal

Sounds good are you getting a safc?I would get 650cc injectors I was at a high injector duty cycle on my 550cc when I was running my 16g at that high boost.Like I said erlier everyone opinion is different about the 255 fuel pump with no afpr sence your a gst you should be fine without it you will barley notice it at idle.I have been running with stock fpr for years with a 255 and still do.But definitly if you want go ahead and get a afpr doesn't hurt.

 

[Calan]

All I was saying is he will be close to 300hp with his current setup and if wanted to run a hx35 he should be able to produce good number above 300whp...

Well that may have been what you wanted to say, but it didn't come out anything like that on the first attempt.

 

[boostednavyac]

Sounds good are you getting a safc?I would get 650cc injectors I was at a high injector duty cycle on my 550cc when I was running my 16g at that high boost.Like I said erlier everyone opinion is different about the 255 fuel pump with no afpr sence your a gst you should be fine without it you will barley notice it at idle.I have been running with stock fpr for years with a 255 and still do.But definitly if you want go ahead and get a afpr doesn't hurt.

The car came with a SAFC and a decent tune, but it definitely feels rich still. and it has noticable trouble at idle, though it hasnt stalled on me yet. Car already has RRE 550s so what ill likely do is do the max boost on pump that the car/IDC can handle safely whenever i get her tuned. And thanks for your opinion on the AFPR seems like half the crowd say you dont need one and the other half say you must

 

[clipto]

The car came with a SAFC and a decent tune, but it definitely feels rich still. and it has noticable trouble at idle, though it hasnt stalled on me yet. Car already has RRE 550s so what ill likely do is do the max boost on pump that the car/IDC can handle safely whenever i get her tuned. And thanks for your opinion on the AFPR seems like half the crowd say you dont need one and the other half say you must

Well just try to tune off your wideband dial in cruise a/f ratio should be like 14.7ish as close and you can get it and try to shoot for 11:1 a/f at wot.But that's if you have a wideband and if not dam well u must get one asap.As for the afpr if you get a 255 and it feels fine then don't worry about it if you think other wise get one it's personal opinion really.

 

[boostednavyac]

Yea I need to get a wideband and a FMIC possiblu link and then ill tune her

 

[clipto]

Yea I need to get a wideband and a FMIC possiblu link and then ill tune her

Just get 1000cc injectors if you get link.

 

[FLASH1970]

If your profile is up to date, I say get some bigger injectors, go E85 if you can, and have fun. I don't see why a stock 7 bolt wouldn't be able to handle anything a 16g can dish out. Maybe get some cams and a LSD... How many EVO's are running around with high miles? Their internals aren't much different if any as far as rods and crank goes and they have a 16g from the factory...

 

[Calan]

Well just try to tune off your wideband dial in cruise a/f ratio should be like 14.7ish as close and you can get it and try to shoot for 11:1 a/f at wot.But that's if you have a wideband and if not dam well u must get one asap.

You can't tune to a specific AFR in closed loop (i.e. "in cruise") even with a WB...you can only adjust fuel and air until fuel trims are as close to zero as possible. If everything is working properly, the AFR will always be very close to 14.7:1 while in closed loop regardless of what you adjust...until you go past the point that the ECU can compensate with the fuel trims.

As for the afpr if you get a 255 and it feels fine then don't worry about it if you think other wise get one it's personal opinion really.

This makes no sense whatsoever. How exactly does a fuel pump "feel"?

The need for an AFPR is based on whether or not you are over-running the rail at low injector pulse widths, or if you need/want the ability to change your base fuel pressure from stock.

 

[LandSpeed-DSM]

Well you can tune closed loop AFR through the DA tables if your trims are hovering over zero.

Or you can change the open loop thresholds.

 

[Calan]

The DA tables are ignored in closed loop; the ECU will still try to target 14.7:1. Changing the OL thresholds just changes when the ECU drops in and out of closed loop. You have to lock the ECU in open loop in order to use the DA tables for tuning at idle and low loads.

With a simulated WB in Link (or a dedicated WB with this feature), you can change the NB switching threshold to something other than 14.7, but that's about it.

 

[clipto]

You can't tune to a specific AFR in closed loop (i.e. "in cruise") even with a WB...you can only adjust fuel and air until fuel trims are as close to zero as possible. If everything is working properly, the AFR will always be very close to 14.7:1 while in closed loop regardless of what you adjust...until you go past the point that the ECU can compensate with the fuel trims.



This makes no sense whatsoever. How exactly does a fuel pump "feel"?

The need for an AFPR is based on whether or not you are over-running the rail at low injector pulse widths, or if you need/want the ability to change your base fuel pressure from stock.

About the a/f tuning I mean just make sure it is around those number you oviously don't want a boost leak and be like 9:1 a/f ratio at cruising or to lean and have a 16:1 a/f ratio, I am sure your car will love that detionation.Just my meaning by this is more make sure it's all dialed in right.

Not literly feel it I mean like if your mind feels like you need one get one it really shouldn't matter unless your that anal.But just for a basic build wasting $200 on a afpr is not worth it imo.