Performance Question (Important - Planning Stage

[Grandavi]

Okay.. First... where the engine is at (some of you will know this)
Rebuilt 7MGTE Shortblock with Wiseco Pistons, polished rods and crank
Rebuilt Head (no porting, stock cams)
1.2 Cometic MLS Headgasket with ARP Studs
1000 cc ID Injectors
HKS EVC-S Boost Controller
HKS Fcon Vpro 3.3 Stand alone mated to a 90 M/T ECU (for idle control and A/C function)
3" vband DP mated to a HKS 3" catback (twin-tip muffler, cats removed)
Tial 44 mm Wastegate (dumptube vents to atmosphere)
HKS SSQL BOV
DM 7MGTE Intercooler upgrade
Supra MKIV Denso Fuel pump upgrade
Aeromotive AFPR
EGR blocked off
SP6262 Turbo DBB 0.68 ar

Still on wasted spark and stock ignition coils and plugs. Keeping my A/C and not planning on going with a FFIM. The R154 is a stage 3 build to handly up to 700 HP (I believe that is at the flywheel, but may be to the wheels) and am currently running a Spec 2+ pressure plate with the stock clutch disc (no slip so far). Stock flywheel.

Here is a dyno of where the car is tuned and set up for now:

So.. the question...

Do I have to pay attention to or plan to upgrade anything to go higher power with maximum reliability?

I am currently on the stock wasted spark setup (not sequential and not COP) so there are limitations, but I am not clear on exactly where the safety limits are.

I am going to run ultra conservative (safe) this summer and then go in for another tune next summer and at that point I would like to creep the power up. Currently I am running at 12 psi, but want to run closer to 16-19 psi. However, by discussions with Reg Reimer and my mechanics I am told that going higher is where my setup will start to run into the grey area with spark/timing and could end up roasting the motor if anything goes awry.

Note that I am not running on a track, this car is more for cruise/show than anything else at this time. If I free up a lot of funds I may start going more toward a track setup but for now I have a rock solid power plant.

Any thoughts to help me plan my next engine stage?

 

[Grandavi]

Just to outline it a little better. My whole worry is that the stock coil setup with stock plugs and the engine running stock cams will have issues with a 91 Octane fuel. If the timing is bang on, I should be okay, but if I start getting a wonky spark, I foresee issues with the pistons.

Will going COP and adjusting my tune for a sequential firing order eliminate that fear or just degrade it. Ultimately I am only looking for reaching 500'ish rwhp as I consider the block built for that and no more. I have about a year to plan for it, so just looking for some technical direction from someone who has done this.

Also, let me know if I am overthinking it for that power level. (I don't run E85 as I am in Canada... tuned for a fairly consistent 91 Octane premium)

(felt it was smarter to run ultra conservative and adjust to reach my goal slowly rather than have to build another engine... )

 

[din904]

A stock ignition in good working order is no problem for 500 rwhp. Things you should be concerned about is running to much timing on pump gas and are you running colder plugs than stock also what did you do to your head are the valve springs stock?

 

[Grandavi]

The head currently is 100% stock. The spark plugs are also unchanged from OEM style (NGK Copper, not sure of number... It's on a bill somewhere).
Running on the fuel I have right now is why I am staying around the 400 rwhp mark. I figure that if I stay this low (it's only 12 psi) for this summer, we can revisit the tune next year and up the boost a bit.

The scary part is that it only takes an instance of trouble at higher boost to melt a piston. I know people say I could run at 19 psi with this setup, but I'm not comfortable with gambling for the extra power. That's why I asked, my tuner locked me in at this "mid" boost because he is 100% sure my car will handle it with no issues. It's a risk/benefit thing and I have never owned a car like this so I have to rely on common sense and others judgement.

 

[din904]

You should be running one step colder plug the ngk 6282 work well for a standard plug but when you start blowing out the spark the ngk 5690 iridium work best from my experience you can also gap the plugs down if needed. The reason I asked about your valve springs is the stock springs have a low seat pressure so valve float is a possibility as you start running higher boost and by that I mean above 20 psi. When I had my car on the dyno the power increase really started to fall off above 23 psi with the stock valve springs.

You should consider upgrading valve springs and cams I know a lot of guys tell you it's not needed at this power level but I rather run cams and make 500 hp at 15psi vs stock cams at 20 or more psi it's much safer less heat means a less chance of detonation. An engine is nothing but a large pump the easier you can get air in and out the more power you will make.

Forged piston can take a lot more abuse than stock and do a better job of dissipating heat the only thing that will destroy them is detonation and even with that it won't happen instantly also learn how to read your plugs every so often you can pull your plugs and look for signs of detonation. Just stick with your plan and continue to build power slowly it's defiantly worth the payoff.

 

[Grandavi]

I have read a bit about cams and head porting. From what I understand all I really need is a mild porting on the exhaust cams to reach 500 reliably. The cams are a bit more confusing because I have heard about idle issues with the 264's (I think I got that number right) and a lot of raves about 272's. Another new area for me to delve into.

Exhaust-wise I think I am at my optimum and don't have to worry about that, as well as the turbo should be more than sufficient. From what I can see so far my Denso fuel pump (I'm not sure if its 290 or 340 lph) is sufficient as well. I haven't done any electrical modifications yet to it as there hasn't been a reason to. My Driftmotion Aeromotive AFPR is sufficient as well, but I plan on upgrading that in the future just because I have heard that it has a flaw of weakening over time and starting to drop off fuel pressure so has to be monitored for adjustment.

One annoying factor is the CEL is constantly on now as the signal that the ECU is supposed to see is being handled by the VPRO so the car sees it as a fault. No effect to operation, but its annoying having an orange light staring at me...

Generally speaking, though, I believe most of what I have to look at is in the head itself. I could pull the head and have it ported and then drop cams into it. At the same time I could deal with the valves/springs to prevent any float. All of this is pretty doable, however, then I have to consider the bearings and the often-talked about oil flow issues. Generally I stay out of redline with my car, but with higher output I find it more difficult as the engine climbs so much faster. Still not used to my adjusted shift timings and have hit redline a couple times in second and third when I didn't expect it. I never realised how much of a difference the power was actually going to make in drivability.

The deeper I get in researching the more I am finding that engines that are pushed to the 500+ limit (7MGTE's that is), the more problems you have with bearings, valves and detonation. My tuner asked if I would be willing to start running race fuel if I truly want to go 500+.

Sometimes I think that maybe I am asking a little too much from my 7M and should be happy with the near 400 rwhp its pushing right now, seeing as I'm not running quarter miles. And then the power bug bites again.. lol.

Ah well.. back to more reading. At least I have a lot of builds that I can read through to find out what they experienced.


A different concern I haven't addressed yet is my rear subframe/differential. Its the original with no visible cracking.. but going this high could push it past its aged limits as well. Amazing how simple it is to do it when you read people's threads... but in reality.. none of it is straight forward.

 

[Rollus]

One annoying factor is the CEL is constantly on now as the signal that the ECU is supposed to see is being handled by the VPRO so the car sees it as a fault. No effect to operation, but its annoying having an orange light staring at me...

if it is an ignition fault code, it is easy to fix with few components from an electronic parts store

 

[Grandavi]

if it is an ignition fault code, it is easy to fix with few components from an electronic parts store

I was told I could do something for this but the description was vague and the one thing I am worst at is electronics.

 

[Rollus]

Ho, so if you worst at electronics et is not a prolem because here we will talk about soldering.

I think that you alter ignition timing with your FCon. Stock ECU check for spark and trigger a CEL code if spark isn't fired within the right timing. Check for codes, and if it is relevant, continue reading.

You need to solder a 1k resistor + a BC548 transistor as per the diagram here: http://goo.gl/JIIdBn (a MAPEcu diagram but the stock ECU to stock igniter part should work).
This way, spark fault won't be seen by the ECU because ECU will see the transistor firing instead of spark..

 

[Grandavi]

Yes it's code 13 and 41 (or is it 14 and 32). Either way it's the VPRO handling timing. That diagram looks pretty straight forward.

 

[gsxr141]

have you thought about water or meth injection?

 

[Grandavi]

I've considers it, but with normal injection there are too many things to consider. If I would do it, I would have controlled injectors per cylinder, not just a spray into the intake plenum.

I'm shooting for the most power I can safely get out of my engine without worrying about causing a problem down the road. I think my next step would be cams and some mild porting on the exhaust. Build the head so I don't have to worry about floating the valves...

With 91 octane, I am limited somewhat if I don't want to risk the engine. The short block was only really built with 700 crank hp in mind.

 

[IndigoMKII]

Why not just switch over to is300 coils with a dh61 igniter?

You could also leave the CPS at 10 BTDC as to keep it as safe as possible for stock electronics.