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........ but my intake peters out around 5500 and the EEC cuts fuel at 6250.........I thought about cutting a couple of inches out of the upper runners, but that's a major PIA.....
I would NOT suggest you take any length out of the upper if you are not going to turn over 6,000 rpm. We've worked with 3 people before with 302-308ci engines that turned 6,000 rpm or less. ALL of them made more power above 5,500 rpm but lost enough mid range that the cars ran a little slower. Not worth the effort imho....... I attached feedback from one......check out his et & mph.......
 

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Discussion Starter #22
I would NOT suggest you take any length out of the upper if you are not going to turn over 6,000 rpm. We've worked with 3 people before with 302-308ci engines that turned 6,000 rpm or less. ALL of them made more power above 5,500 rpm but lost enough mid range that the cars ran a little slower. Not worth the effort imho....... I attached feedback from one......check out his et & mph.......
WOW!!! Makes sense and I'm glad you posted that. I've done machining (guides, seats, boring, valve jobs, etc) back in the 90's while in college, but that was a long time ago. That said I have access to a full machine shop at a local college so I'm very open to trying to ring out as much power as possible while keeping things budget. Hence my thoughts of bigger valves, bumping the compression, etc. Thought about maybe angle milling the heads to help with valve angles, bump the compression, etc. Would love to use some smaller stem valves, thin rings, light rotator, etc but the budget goes out the window quick.

My goal is to make it as fast as possible (still streetable) while keeping the 13 second look (cast iron heads, explorer intake, etc)
 

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I would check that porting to verify the quality. Definitely CC the heads to see where they are. I would mill to achieve 60-61cc, some of those GT-40s have very large chambers 65-68cc. Keep track of it so you can get longer push rods or have a good starting point on shims.

Get a good MAF, 75mm bullet and stock CAI or Anderson Power Pipe and a 80mm in the fender. I have used the BBK style CAI and I don't think the MAF sensors like that quick 90 right before the meter. You have to get a MAF specific to that CAI if you want to use them. And, they heat soak. I would just use a stock set up with the bullet and a K&N. Works good, looks good, no hassle.

I also always lose the EGR and block off the port to keep the hot exhaust from migrating up the intake. Just use the felpro intake gaskets with the steel insert in them. Keeps the upper cool.

That should help.
 

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I would NOT suggest you take any length out of the upper if you are not going to turn over 6,000 rpm. We've worked with 3 people before with 302-308ci engines that turned 6,000 rpm or less. ALL of them made more power above 5,500 rpm but lost enough mid range that the cars ran a little slower. Not worth the effort imho....... I attached feedback from one......check out his et & mph.......
I can back this up, I'd tried a couple different ways to make this work, but the longer runners just worked better at the track, the shorter runners made a higher peak number, but only at the peak. Had we had a stroker, or been able to turn more RPM then the shorter runners might have been better.
 
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Discussion Starter #25
I would check that porting to verify the quality. Definitely CC the heads to see where they are. I would mill to achieve 60-61cc, some of those GT-40s have very large chambers 65-68cc. Keep track of it so you can get longer push rods or have a good starting point on shims.

Get a good MAF, 75mm bullet and stock CAI or Anderson Power Pipe and a 80mm in the fender. I have used the BBK style CAI and I don't think the MAF sensors like that quick 90 right before the meter. You have to get a MAF specific to that CAI if you want to use them. And, they heat soak. I would just use a stock set up with the bullet and a K&N. Works good, looks good, no hassle.

I also always lose the EGR and block off the port to keep the hot exhaust from migrating up the intake. Just use the felpro intake gaskets with the steel insert in them. Keeps the upper cool.

That should help.
Thanks. I cut these heads .030 as they had the bigger chamber. I wish I had cc'd them go know what they are. I will do that soon. I'm guessing they are 61 - 63 cc based off the .030 cut. I was able to use the stock push rods with no shims. Nice pattern on the valve and @1/4 - 1/2 turn preload.

I have a stock airbox with K & N sitting there on the shelf. I didn't run it because, I needed a new hose and I picked up a brand new BBK cold air kit for cheap from a buddy. I'm wishing I had run the stock box setup though as I want the OEM look.

Do you know if either of these setups is restrictive at 107-110mph level (my end goal) vs the Anderson power pipe?

Same question with the C & L 73mm Maf? Is a 75mm bullet that much better? My driveability is perfect with the 19's and the meter clocked so that the sensor is on the outside of the bend.

EGR is blocked off. Thanks for the feedback----appreciate it.
 

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Discussion Starter #26
I can back this up, I'd tried a couple different ways to make this work, but the longer runners just worked better at the track, the shorter runners made a higher peak number, but only at the peak. Had we had a stroker, or been able to turn more RPM then the shorter runners might have been better.
Thanks for the feedback! It's easy to get caught up in the peak hp number, but the area under the curve is probably way more significant in this case.

That said, I'm still trying to figure out the cam. I like the looks of Ed's cams. The big is better mentality has me wanting to go with:

GT40-KR2
.555/.536
218/224 @.050
110 ls
2300-6300

I'm thinking based off your feedback and other comments above that this one would be better:

GT40-KR1
.565/.555
214/218 @.050
108 ls
1800-5800

These intakes aren't known for their high rpm prowess though so maybe this one would better:

GT40-KR1-A
.550/.530
214/218 @.050
108 ls
1500-5500

Thoughts????
 

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Thanks. I cut these heads .030 as they had the bigger chamber. I wish I had cc'd them go know what they are. I will do that soon. I'm guessing they are 61 - 63 cc based off the .030 cut. I was able to use the stock push rods with no shims. Nice pattern on the valve and @1/4 - 1/2 turn preload.

I have a stock airbox with K & N sitting there on the shelf. I didn't run it because, I needed a new hose and I picked up a brand new BBK cold air kit for cheap from a buddy. I'm wishing I had run the stock box setup though as I want the OEM look.

Do you know if either of these setups is restrictive at 107-110mph level (my end goal) vs the Anderson power pipe?

Same question with the C & L 73mm Maf? Is a 75mm bullet that much better? My driveability is perfect with the 19's and the meter clocked so that the sensor is on the outside of the bend.

EGR is blocked off. Thanks for the feedback----appreciate it.
I've had a lot of these sort of combos and haven't experienced much difference in actual power, but the ProM stuff has always been trouble free. I've had the Power Pipe but I don't like grinding the hole bigger in the fender well. Can't go back once you start that. I just don't think its necessary for that sort of combo.
For example:
I had an 89 coupe, Gt-40 crate with the 64cc X heads, Anderson B-31, ported Gt-40 tubular, Power Pipe ,80mm MAF in the fender, 30lb injectors, rebuilt T-5, FMS Shorties with O/R H pipe, Flows, etc, etc. Made 310/330 ish on the dyno.
Next car, 89 convertible, stock bottom end, stock cam, same intake, AFR 165's with the 58cc chambers, 1.72 rockers, stock box and cai, 75 mm bullet, FMS shorties with Bassni O/R, X Flows, etc, etc..Car made 306/335ish through and old school Tremec 3550. So you could probably say that with the T-5 it would have made more than the coupe. Are the AFR's that good? I don't know.

I guess my point is at this level I don't think a thing like the aftermarket cai is that much of a factor in overall power output. The Pro M probably has more of an affect on drive-ability where you spend all the time, and tune-ability later. Some tuners don't like the C&L at all.

At this point in my life I just like what I like. I have a ported GT-40 iron set up on my car now and its my favorite so far, Fox #7. There were no issues setting them up, they flow very well and I think iron heads have a better sound, but I am super old school. I bought the heads from a guy in Maryland that ports for dirt track racers. Then I sent them to Thumper and had him mill them to 61cc, fine tune the porting and do a better valve job. Do I have more in them than a used aluminum set? Absolutely. Do I give two ****s? Absolutely not. In fact, I like them so much I'm having another set built by Big Dogs Porting in Chicago. More porting, bigger valves, better springs yatta yatta. He just finished a GT-40 intake for me that average flowed 335 (heavily welded) so that and the new heads will go on a 331 soon.

I'd say fix your heads, make sure your lower is flowing, make sure the upstream air has somewhat of a good funnel affect. (75mm bullet, 70mm Accufab, etc) and practice driving.

my two cents
 

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Yes full weight gt plus I'm 275 lol
So the track weight of the car should be around 3650-3700 lbs with you in it. What was your horsepower goal (target) with the original combo to achieve 107-110 MPH?

I know my full loaded 90 GT with AOD weighed 3475 on the certified truck scale at work, plus me at 245 lbs for a total of 3720, so I can associate with you with a heavy car.
 

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Discussion Starter #29
I've had a lot of these sort of combos and haven't experienced much difference in actual power, but the ProM stuff has always been trouble free. I've had the Power Pipe but I don't like grinding the hole bigger in the fender well. Can't go back once you start that. I just don't think its necessary for that sort of combo.
For example:
I had an 89 coupe, Gt-40 crate with the 64cc X heads, Anderson B-31, ported Gt-40 tubular, Power Pipe ,80mm MAF in the fender, 30lb injectors, rebuilt T-5, FMS Shorties with O/R H pipe, Flows, etc, etc. Made 310/330 ish on the dyno.
Next car, 89 convertible, stock bottom end, stock cam, same intake, AFR 165's with the 58cc chambers, 1.72 rockers, stock box and cai, 75 mm bullet, FMS shorties with Bassni O/R, X Flows, etc, etc..Car made 306/335ish through and old school Tremec 3550. So you could probably say that with the T-5 it would have made more than the coupe. Are the AFR's that good? I don't know.

I guess my point is at this level I don't think a thing like the aftermarket cai is that much of a factor in overall power output. The Pro M probably has more of an affect on drive-ability where you spend all the time, and tune-ability later. Some tuners don't like the C&L at all.

At this point in my life I just like what I like. I have a ported GT-40 iron set up on my car now and its my favorite so far, Fox #7. There were no issues setting them up, they flow very well and I think iron heads have a better sound, but I am super old school. I bought the heads from a guy in Maryland that ports for dirt track racers. Then I sent them to Thumper and had him mill them to 61cc, fine tune the porting and do a better valve job. Do I have more in them than a used aluminum set? Absolutely. Do I give two ****s? Absolutely not. In fact, I like them so much I'm having another set built by Big Dogs Porting in Chicago. More porting, bigger valves, better springs yatta yatta. He just finished a GT-40 intake for me that average flowed 335 (heavily welded) so that and the new heads will go on a 331 soon.

I'd say fix your heads, make sure your lower is flowing, make sure the upstream air has somewhat of a good funnel affect. (75mm bullet, 70mm Accufab, etc) and practice driving.

my two cents
I agree. That was my intent all along. This car isn't meant to be a drag car or to put up optimal ets. However, the mph obviously will indicate the power the car is making. Power = Fun

I'm very curious to see your results with Big Dog Porting. I would love to do that, just don't want to spend that kind of money on this car at this time. Thanks for the feedback.
 

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Discussion Starter #30
So the track weight of the car should be around 3650-3700 lbs with you in it. What was your horsepower goal (target) with the original combo to achieve 107-110 MPH?

I know my full loaded 90 GT with AOD weighed 3475 on the certified truck scale at work, plus me at 245 lbs for a total of 3720, so I can associate with you with a heavy car.
My car is a 5 speed so I think my weight would be lower. I had a nicely optioned 1993 notchback with a 5 speed and it weighed 3120. That number is a little skewed though as it had a S-trim blower kit but aluminum heads when I weighed it. Probably the two items canceled each other out or close. On this car, my guess would be maybe 3300-3350 depending on how much fuel in the tank.

No horsepower target, just performance based off similar combos. I really felt that this setup should run 106-107. I was hoping for 107-109. Good to want I suppose.

The car runs great, honestly I'll probably tighten up the quench which will help with detonation suppression and bumping the compression. Maybe a cam. I'm leaning heavily towards the GT40-KR1. Thanks for the feedback.
 

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I agree. That was my intent all along. This car isn't meant to be a drag car or to put up optimal ets. However, the mph obviously will indicate the power the car is making. Power = Fun

I'm very curious to see your results with Big Dog Porting. I would love to do that, just don't want to spend that kind of money on this car at this time. Thanks for the feedback.
His stage 2 head package is $900 and he supplies the heads. I sent him my intake and he is working the heads still. Both and I'm around $1300. My intake flows 335, soooooo......
 

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my kids sn95 pretty much like yours
just trick flow intake
installed at 39 intake close. b cam,1.72
piston was .001 proud of the deck (luck) ..041 compressed
promm,75mm tb
4 bar heads, sort look like eds, i did ex to and radius that
410s no cats
i searched around and found what thought was a good tuner
and had a chip burnt.

he put 2 lengths on {2x in a row) a true 12.90 350 nismo and i dont even have much ign in it.

haven't been to track yet

i paid 200 for the e7 heads and a b cam, that had 1.94 valves and trick flow springs and 1.72 roller rockers
i then took those valves/springs and put them in gt40ps and flow tested the crap out of everything
paid 200 for prom m 75 and ford 24s and a fuel rail and regulator
. intake, 75mm tb and exhaust and 410 was on the car when he bought it , p heads at bone yard 78.00
i bought 2 sets or those, junked some valves trying back cuts, even tried some 50 seats on bench, low buck as it get. and its probably faster than my coupe in my sig 20 years ago,na
 

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i should add , he can drive, but i am sure i can drive better, he is only 19 and this is 1st real car. on the stock tach shifts at 6300 seem correct.
 

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Here is set of world sportsmans i did for a sbc recently
Short turn shapes come in many shapes and sizes. All heads are different . Those 2 shapes are completely different.not just in looks.
 

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