GT350 Engine Refresh Time!

[Mjc1241]

Any thought about going with a ported CJ intake manifold and accompanying throttle body for this build? That would possibly get you to the 550 rwhp on 93; definitely on E85. If I missed that in the thread; my apologies.

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[AceOne]

Any thought about going with a ported CJ intake manifold and accompanying throttle body for this build? That would possibly get you to the 550 rwhp on 93; definitely on E85. If I missed that in the thread; my apologies.

I doubt it will get to 550 whp on 93. I have that setup on my 5.2 CPC engine and a great E85 tune. I make 530 SAE whp on a tight dyno. Not a dynojet. My goal for the one I'm building now is 575 whp but I'm not sure that is even possible... at least not in a durable, reliable tune to run hard on track. It has been done with Stage 3 VCT lockout cams and shown on loose dynos on STD factored hp numbers (saw one at 593 whp on FTW fuel) but the torque down low is terrible and everyone that I know of that tried them on track has pulled the cams out and gone back to VCT and has gone faster on hotlaps after pulling them.

 

[Mjc1241]

Ok. I assumed with headers, ported heads, ported CJ manifold/throttle body and tune, it would get you there. Thanks for setting me straight on that. Got to recalibrate my approach now on what I may do in the future.

 

[lgvenable]

Any thought about going with a ported CJ intake manifold and accompanying throttle body for this build? That would possibly get you to the 550 rwhp on 93; definitely on E85. If I missed that in the thread; my apologies.

It's just as easy to do 93 octane as it is to do 95 octane - and you can run a hotter tune. If you're in a state with E85 like me..Oklahoma-> I mix my own blends. to get either. FYI we don't have 93 octane, only 91 octane gas.

Prior to the 17 Mustang GT, I was running a focus ST as a daily driver.. I ran it on 93/94 octane made to the recipes below and never had a single knock; as the ST was tuned w/a cobb tuner. That made it easy to monitor cylinder 1 and 4 for knock, plus total events..and I never had any in 3+ years of 93 octane made at the pump to that recipe, just turn off the car, then add corn juice first, topped off by the E10. As I drove off, I wiggled the wheel and looked like I was warming the tires on a track..but I was really mixing the gas tank.

What you typically find is E85 at these stations isn't always whats in in those pumps..so watch out believing that that E85 sticker. Here in OK, the pumps contain E70. Kum & Go used to change to E70 seasonally; now they use E70 year-round. I learned to call the fuel engineers at Kum and Go corporate to get the info on the corn juice being sent to my favorite station...where I go its E70, and I was told they simplified by going E70 year-round everywhere in OK. . I occasionally verify that the tanks are at 70% ethanol via the use of the small volumetric % gas/% ethanol testers sold on amazon.

Since we run E70 here in OK, I always put in 100 octane value for E70, and also use 91 octane E10.
93 OCTANE: 3.5 gallons/E70 + 6.5 gallon 91 oct E10 the Wallace racing link calls this recipe 94 octane E31\ note: a 2nd calculator no longer available called this 93 octane.
95 OCTANE 4.5 gallon E70 + 5.5 gallon 91 oct E10. the Wallace racing link calls this recipe 95 octane E37

Wallace Racing E85 Calculator Link: http://www.wallaceracing.com/ethanol-mix-calc.php

If that is the case then I will happily take the original design that eats a little oil. Mine has been fairly consistent at 1 quart every 2k miles

My old 90 Mustang GT used about the same amount, designed to do this by Ford, as those older mustang gt were designed with pistons to allow that blow-by.

 

[Epiphany]

My old 90 Mustang GT used about the same amount, designed to do this by Ford, as those older mustang gt were designed with pistons to allow that blow-by.

Most every engine has a piston and ring package that allows blow-by. And with the passage of time and miles it only increases.

The 302's that came in Fox bodies, whether they had forged or hypereutectic pistons, did the same thing in varying degrees.

 

[JR369]

I believe piston slap won't change with different piston rings. I thought that's from the piston being forged aluminum. But tighter tolerances I think will reduce oil consumption but sacrifice a small amount of HP.

As an FYI, my `99 911 manual states almost all of the same things/issues: forged pistons, tolerances that can cause high oil consumption (up to 600 miles per quart is acceptable and even expected with track / high speed use). So 20 years later, it's the same thing. Tried and true tricks of engine building, I guess.

Proper piston to wall clearance is essential to successful operation. Some small clearance is essential to provide room for the lubricating medium, but most clearance is built in to accommodate component expansion rates as an engine comes up to operating temperature. The piston profile plays an important role in determining clearance. Tighter clearances tend to reduce piston slap (clatter) on cold startup and they provide a more stable fit to promote good ring seal. If the piston is too loose in the bore this slap can crack the piston at the skirt. I personally have witnessed a ruined engine due to a lower piston skirt breaking off. We also must take into account the material pistons are made from. For example, the higher-expanding 2618 piston may have a larger initial clearance than a 4032 piston, but once the engine reaches operating temperature, both pistons will have very similar running clearances. So imo, the thought that a tighter initial piston to wall clearance on cold start up could result in loss of horsepower may not be the case at all.

 

[AceOne]

It's just as easy to do 93 octane as it is to do 95 octane - and you can run a hotter tune. If you're in a state with E85 like me..Oklahoma-> I mix my own blends. to get either. FYI we don't have 93 octane, only 91 octane gas.

Prior to the 17 Mustang GT, I was running a focus ST as a daily driver.. I ran it on 93/94 octane made to the recipes below and never had a single knock; as the ST was tuned w/a cobb tuner. That made it easy to monitor cylinder 1 and 4 for knock, plus total events..and I never had any in 3+ years of 93 octane made at the pump to that recipe, just turn off the car, then add corn juice first, topped off by the E10. As I drove off, I wiggled the wheel and looked like I was warming the tires on a track..but I was really mixing the gas tank.

What you typically find is E85 at these stations isn't always whats in in those pumps..so watch out believing that that E85 sticker. Here in OK, the pumps contain E70. Kum & Go used to change to E70 seasonally; now they use E70 year-round. I learned to call the fuel engineers at Kum and Go corporate to get the info on the corn juice being sent to my favorite station...where I go its E70, and I was told they simplified by going E70 year-round everywhere in OK. . I occasionally verify that the tanks are at 70% ethanol via the use of the small volumetric % gas/% ethanol testers sold on amazon.

Since we run E70 here in OK, I always put in 100 octane value for E70, and also use 91 octane E10.
93 OCTANE: 3.5 gallons/E70 + 6.5 gallon 91 oct E10 the Wallace racing link calls this recipe 94 octane E31\ note: a 2nd calculator no longer available called this 93 octane.
95 OCTANE 4.5 gallon E70 + 5.5 gallon 91 oct E10. the Wallace racing link calls this recipe 95 octane E37

Wallace Racing E85 Calculator Link: http://www.wallaceracing.com/ethanol-mix-calc.php



My old 90 Mustang GT used about the same amount, designed to do this by Ford, as those older mustang gt were designed with pistons to allow that blow-by.

I would really be cautious about blending regular fuel and E85 or E70 fuel just to achieve a certain octane rating. Ethanol has way higher fuel demand versus non ethanol fuel.. If you have a flex fuel tune then you may be okay but for non Flex fuel tune you really can't be mixing them...you will run too lean. With just E10 fuel changes stoch from 14.7 to 14.2 (all new cars are set to 14.2 stoch now) which most tunes can handle but anything over 15 % ethanol will drop the stoch too much and you will not be providing enough fuel for the engine under full load. Today's newer engines with the wideband O2 sensors and adaptable fuel tables can adjust for the lean conditions but only to a certain extent. My 2016 stang with OEM or 93 E10 fuel tune is only rated for max E15 as shown on the filler neck. I have a dedicated E85 tune and not flex tune. I also have a Zietronix Ethanol content gauge so I always know my percent Ethanol.

I have filled up at Kum & Go and as of last year when attending Mid-America Shelby it was varing from E68 to E74. All my E85 fuel here at HEB and Sunoco are always above E80.


Is your car Flex fuel capable?

 

[galaxy]

I am going to make one small comment simply because I just can't keep up with how fast this thread is moving and the deep tech involved, but I will simply say this...how amazing is it that we are here discussing the credibility and the capability of reliable, sub 400 cubic inch, 500 plus HP NA engines?!?!?!?

 

[honeybadger]

Under high load and carousel turns some cars have pushed oil out the PVC line past catch cans and blew oil out the air filter. It makes a mess...I even had one car spin out behind me after mine burped once. It just spit it out . soaks the air filter and blows ingested oil out the tail pipe...hence the spinout of the Camaro behind me....it was a Camaro so no harm, no foul! I did apologize to him afterward though and was glad he was okay and only looped it and kept if on track.

Interesting. I'd never heard of this before. Don't think I have ever experienced it. At least now I'll know what it is if it does happen!

Kevin loved the thread, used it to help understand the coyotes internals, since I'm new to this engine.

I did have a coupe of questions, based on work, as I didn't see some things I did in my NA build in I had done on an LS7 for durability and power... didn't notice if you chose special valve guides? In my build mold-star 90's were used, they're from F1, and the shop that did my heads made two big changes 1st- stud mounted roller rockers to make sure there was absolutely zero side loading on the valve stems..major issue on about 4% of LS7's in the early days of that engine; combined with the MS90 guides Kohle's claim was 100,000 street miles w/o any issues in the heads. The early LS7's could show issues at 18,000 miles on the street. When that work was done, I debated building a track LS7, but didn't; rather based the build to be used mainly on the street, so that I had minimal bottom end changes. However if I had gone for a track build I would have used piston squirters too as well as tearing into the short block like you have., I didn't see that you did that, or are you waiting for the next refresh - or did I miss them?
Great build! ..Larry

The valve guides are a special racing-spec bronze guide that RGR uses. I can't remember the brand off the top of my head, but I'll ask Aaron next time I speak to him.

Regarding the oil squirters (assuming that's what you're referring to at the bottom of your post), they'll be retained. According to Tim, he's able to keep them with the sleeving process and highly recommends them in road course setting. Here's a quick snap of the OEM one on cylinder #8 (tiny little hole at the bottom of the cylinder).

Subbed. Thanks for all the great info!

While I have no intentions of rebuilding my purely street-driven car that only sees about 4000 miles per year, if it becomes my forever-car I’m staring down the barrel of this at some point.

At a minimum, I'd highly recommend the headwork once you're out of warranty or decide that it's time to tune it

Any thought about going with a ported CJ intake manifold and accompanying throttle body for this build? That would possibly get you to the 550 rwhp on 93; definitely on E85. If I missed that in the thread; my apologies.

I hadn't considered it TBH. I've heard that the CJ intake requires you to drop the engine and I wasn't super motivated to do that. I anticipate if all goes well with this build in 2019, I'll play with adding power through cams and the CJ intake in 2020.

This year I'm entirely focused on reliability.

I am going to make one small comment simply because I just can't keep up with how fast this thread is moving and the deep tech involved, but I will simply say this...how amazing is it that we are here discussing the credibility and the capability of reliable, sub 400 cubic inch, 500 plus HP NA engines?!?!?!?

I can barely keep up myself. Lots of great info flowing. Who would have thought digging into the Voodoo would spur lots of convo

 

[Epiphany]

I am going to make one small comment simply because I just can't keep up with how fast this thread is moving and the deep tech involved, but I will simply say this...how amazing is it that we are here discussing the credibility and the capability of reliable, sub 400 cubic inch, 500 plus HP NA engines?!?!?!?

Even more amazing is that just when we finally see the technology at play that allows this kind of power it'll be killed off in favor of electric/hybrid engine combinations.

 

[honeybadger]

Even more amazing is that just when we finally see the technology at play that allows this kind of power it'll be killed off in favor of electric/hybrid engine combinations.

I REALLY hope this rumor of a 5.5 liter FPC from GM is true. If so, it might be able to help delay the inevitable extinction of the high HP, N/A motors

 

[AceOne]

I am going to make one small comment simply because I just can't keep up with how fast this thread is moving and the deep tech involved, but I will simply say this...how amazing is it that we are here discussing the credibility and the capability of reliable, sub 400 cubic inch, 500 plus HP NA engines?!?!?!?

Especially when they are only 302 and 317 cubic inches and can turn over 8K and peak HP in the 7600 to 7700 rpm range! I agree with you! Ford has done an amazing job imo...I can't believe how so many people complain about some high oil usage. If motor blows then I can see their point. But for $55K to $68K for what you get in an R...just amazing!!
My $11,000 brand new 85 Fox GT HO with its 210 Crank hp was getting me in all kinds of trouble as a teenager!! I could dump the clutch at 5 K and leave 300 ft tracksin first and rip more in 2nd...with 2.73 rear gear and still got 24 mpg on highway. I couldn't even drive it in OD at the speed limit...55 mph! :( it was at fast idle of 1200 rpm in OD at 55...so it routinely saw 75 mph at 1650 rpm. I'm not to sure it would do all that on my 335 wide BFG Rival tires that's is on Code_Blu though!!

 

[galaxy]

Meh, I'm usually the optimist in the room...I don't think our days are over just yet!

 

[galaxy]

Especially when they are only 302 and 317 cubic inches and can turn over 8K and peak HP in the 7600 to 7700 rpm range! I agree with you! Ford has done an amazing job imo...I can't believe how so many people complain about some high oil usage. If motor blows then I can see their point. But for $55K to $68K for what you get in an R...just amazing!!
My $11,000 brand new 85 Fox GT HO with its 210 Crank hp was getting me in all kinds of trouble as a teenager!! I could dump the clutch at 5 K and leave 300 ft tracksin first and rip more in 2nd...with 2.73 rear gear and still got 24 mpg on highway. I couldn't even drive it in OD at the speed limit...55 mph! :( it was at fast idle of 1200 rpm in OD at 55...so it routinely saw 75 mph at 1650 rpm. I'm not to sure it would do all that on my 335 wide BFG Rival tires that's is on Code_Blu though!!

I had a few fox bodies myself. Your comments reminded me of a youtube story I saw! There was a guy on youtube with a bone stock (sans cat back and CAI) late fox body with somewhere around 300,000 miles on it. He did a random dyno and apparently put down like 220 HP or something. Call me crazy, but "225 HP" should never equal 220 at the wheel. Impressive, very impressive, if true. I'll see if I can find it.

Sorry to sidetrack. Back to your regularly scheduled program already in progress....

 

[AceOne]

@honeybadger

The CJ is great and I am very glad I finally got it installed. But it is very involved process to make it fit in a GT350. My GT has more clearance but I have a CF Vented hood and I had to cut out a support rib and tweak it at the rear support also and I have lowered the motor almost 1/2" The composite oil pan give less clearance to the EPAS and k-member.

I knew another racer that had my vented hood and put the CJ on his right before and event...and couldn't close the hood.. He cut up the CF hoods supports and fiber glassed it if 24 hours so he could make the race. After that I ran it the 5.2 CPC from fall of 2016 to summer of 2018 with a ported GT350 manifold until i knew I had time to do the hood modifications properly. I was just making over 505 whp on E85 with that setup. 494 whp on 93 octane.

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