383 H/C/I Results!!
02-18-2015, 07:12 PM
#42
11 Second Club
Thread Starter
1 7/8" worth 6-8 HP on your combo over 1 3/4" not including Y behind it.
1 3/4-1 7/8 step probably 10-15 HP & Torque through 2500-6500 Rpm.
Step is the way to go if it's in the budget, all plus no minus,
Better then either 1 3/4 or 1 7/8 for your combo!
Tony Mamo ported Fast with your combo, ported heads,good sized cam,
and 4" stroke worth at least 10-12, maybe as much as 15 HP!
1 3/4-1 7/8 step probably 10-15 HP & Torque through 2500-6500 Rpm.
Step is the way to go if it's in the budget, all plus no minus,
Better then either 1 3/4 or 1 7/8 for your combo!
Tony Mamo ported Fast with your combo, ported heads,good sized cam,
and 4" stroke worth at least 10-12, maybe as much as 15 HP!
No worries.
02-19-2015, 10:07 AM
#43
ARH will do a stepped header design on any of their headers they have in the catalog for an additional cost.
IIRC it's 150-200 dollars more for the stepped design over what they list in the catalog.
Call ARH and ask for Stephen, he can help you get what you need. We're also a dealer for ARH as well and I'd be glad to get you the headers you want.
02-19-2015, 02:14 PM
#44
Regarding header choice, I'm probably one of the few guys to have actually tested this exact scenario on a 383 in a stout combination that would show the upside and downside of either.
I tried both a 1.75 to 1.875 stepped ARH and a straight 1.875 ARH....the stepped header did not do what conventional wisdom might indicate.....it wasnt the best of both worlds and in fact the shape of the curve looked more like the 1.75 I replaced than ultimately what I settled on which was the straight 1.875 tube.
I was kind of disappointed but these are the exact reasons you spend the time to do real world testing. The larger tube did just what I hoped it would do increasing the 5-7K portion of the powerband about 6-8 HP (8 HP peak) and carried flatter past peak showing about 10 more from 6800-7200 in my solid street roller 383.
Both the 1.75 straight and the 1.75 stepped were better around 3500-4200 by some 15 ft/lbs or so and that is the trade you make when stepping into the tube better aimed at filling in the top of the curve. For my application (a street/strip car), and knowing how I typically drive the car, that middle RPM part of the power/torque curve is no man's land. Im either cruising under 2500 most of the time just tooling around on the street, or I drop it into the correct gear and launch the car at 5K+ when I want to have some fun and experience the God of G-force we all worship.
Now hypothetically if you road race the car on a short/medium length course and see 3500-4000 RPM's coming off tight corners, the right choice becomes the smaller tube IMO but if your mainly discussing street, roll, or drag racing, HP is what wins races so assuming you have a left pedal or a converter with enough stall to get you in the sweet spot quickly, the higher RPM charge of the larger header will give you the most performance bang for your buck.
Hope this helps guys....
-Tony
I tried both a 1.75 to 1.875 stepped ARH and a straight 1.875 ARH....the stepped header did not do what conventional wisdom might indicate.....it wasnt the best of both worlds and in fact the shape of the curve looked more like the 1.75 I replaced than ultimately what I settled on which was the straight 1.875 tube.
I was kind of disappointed but these are the exact reasons you spend the time to do real world testing. The larger tube did just what I hoped it would do increasing the 5-7K portion of the powerband about 6-8 HP (8 HP peak) and carried flatter past peak showing about 10 more from 6800-7200 in my solid street roller 383.
Both the 1.75 straight and the 1.75 stepped were better around 3500-4200 by some 15 ft/lbs or so and that is the trade you make when stepping into the tube better aimed at filling in the top of the curve. For my application (a street/strip car), and knowing how I typically drive the car, that middle RPM part of the power/torque curve is no man's land. Im either cruising under 2500 most of the time just tooling around on the street, or I drop it into the correct gear and launch the car at 5K+ when I want to have some fun and experience the God of G-force we all worship.
Now hypothetically if you road race the car on a short/medium length course and see 3500-4000 RPM's coming off tight corners, the right choice becomes the smaller tube IMO but if your mainly discussing street, roll, or drag racing, HP is what wins races so assuming you have a left pedal or a converter with enough stall to get you in the sweet spot quickly, the higher RPM charge of the larger header will give you the most performance bang for your buck.
Hope this helps guys....
-Tony
__________________
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
02-19-2015, 04:36 PM
#45
Naturally a larger diameter primary results in a more intense reflective wave during valve overlap for a narrower band of RPM (higher RPM) making more peak torque and HP.
The main reason I suggested the step header is the OP seems to enjoy his broad torque curve and might not want to sacrifice much if any of that.
The step header reflects a less intensive wave over a broader range of RPM resulting in a broader power curve, but less power at peak torque and peak hp. The slight addition of diameter will help to ease some pumping losses up top, but not as much as a straight tube 1.875".
That said, headers correlate directly with cam timing, namely valve overlap. In Tony's case he probably had a much larger camshaft with more valve overlap than in the OP's case.
It would of been interesting to see Tony's test done with a milder camshaft that possessed less overlap versus what I assume his solid roller camshaft had.
The main reason I suggested the step header is the OP seems to enjoy his broad torque curve and might not want to sacrifice much if any of that.
The step header reflects a less intensive wave over a broader range of RPM resulting in a broader power curve, but less power at peak torque and peak hp. The slight addition of diameter will help to ease some pumping losses up top, but not as much as a straight tube 1.875".
That said, headers correlate directly with cam timing, namely valve overlap. In Tony's case he probably had a much larger camshaft with more valve overlap than in the OP's case.
It would of been interesting to see Tony's test done with a milder camshaft that possessed less overlap versus what I assume his solid roller camshaft had.
02-19-2015, 05:32 PM
#46
Naturally a larger diameter primary results in a more intense reflective wave during valve overlap for a narrower band of RPM (higher RPM) making more peak torque and HP.
The main reason I suggested the step header is the OP seems to enjoy his broad torque curve and might not want to sacrifice much if any of that.
The step header reflects a less intensive wave over a broader range of RPM resulting in a broader power curve, but less power at peak torque and peak hp. The slight addition of diameter will help to ease some pumping losses up top, but not as much as a straight tube 1.875".
That said, headers correlate directly with cam timing, namely valve overlap. In Tony's case he probably had a much larger camshaft with more valve overlap than in the OP's case.
It would of been interesting to see Tony's test done with a milder camshaft that possessed less overlap versus what I assume his solid roller camshaft had.
The main reason I suggested the step header is the OP seems to enjoy his broad torque curve and might not want to sacrifice much if any of that.
The step header reflects a less intensive wave over a broader range of RPM resulting in a broader power curve, but less power at peak torque and peak hp. The slight addition of diameter will help to ease some pumping losses up top, but not as much as a straight tube 1.875".
That said, headers correlate directly with cam timing, namely valve overlap. In Tony's case he probably had a much larger camshaft with more valve overlap than in the OP's case.
It would of been interesting to see Tony's test done with a milder camshaft that possessed less overlap versus what I assume his solid roller camshaft had.
I'm not sure what the OP is running....no time to look, but my SR cam was more of a street roller and wasn't very large (it drove very well). Accounting for the fact its was a solid roller (which acts like a hyd roller some 6-8 degrees smaller), it was the equivalent of an HR say 235 degrees on the intake and 241 degrees on the exhaust and I ground the cam on a user friendly 114 LSA. The overlap was pretty modest for that displacement all things considered.
As I mentioned in my last post, I was actually expecting the step header to do better considering it wasn't a larger displacement build where the straight 1.875 pipe would be more of a no brainer to shine. There was only about a 10" section of 1.75 pipe before the step to 1.875 so there was quite a bit of the larger tubing before the collector which was a merge style collector in both designs.
It was interesting.....made the swap to the 1.875 a little sweeter cause I was a little disappointed with the step header and didn't think I would see that large a gain going to the straight tube.
Good stuff....always learning and unlearning in this hobby.....goes with the territory
-Tony
__________________
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
02-19-2015, 05:43 PM
#47
Hi Martin,
I'm not sure what the OP is running....no time to look, but my SR cam was more of a street roller and wasn't very large (it drove very well). Accounting for the fact its was a solid roller (which acts like a hyd roller some 6-8 degrees smaller), it was the equivalent of an HR say 235 degrees on the intake and 241 degrees on the exhaust and I ground the cam on a user friendly 114 LSA. The overlap was pretty modest for that displacement all things considered.
As I mentioned in my last post, I was actually expecting the step header to do better considering it wasn't a larger displacement build where the straight 1.875 pipe would be more of a no brainer to shine. There was only about a 10" section of 1.75 pipe before the step to 1.875 so there was quite a bit of the larger tubing before the collector which was a merge style collector in both designs.
It was interesting.....made the swap to the 1.875 a little sweeter cause I was a little disappointed with the step header and didn't think I would see that large a gain going to the straight tube.
Good stuff....always learning and unlearning in this hobby.....goes with the territory
-Tony
I'm not sure what the OP is running....no time to look, but my SR cam was more of a street roller and wasn't very large (it drove very well). Accounting for the fact its was a solid roller (which acts like a hyd roller some 6-8 degrees smaller), it was the equivalent of an HR say 235 degrees on the intake and 241 degrees on the exhaust and I ground the cam on a user friendly 114 LSA. The overlap was pretty modest for that displacement all things considered.
As I mentioned in my last post, I was actually expecting the step header to do better considering it wasn't a larger displacement build where the straight 1.875 pipe would be more of a no brainer to shine. There was only about a 10" section of 1.75 pipe before the step to 1.875 so there was quite a bit of the larger tubing before the collector which was a merge style collector in both designs.
It was interesting.....made the swap to the 1.875 a little sweeter cause I was a little disappointed with the step header and didn't think I would see that large a gain going to the straight tube.
Good stuff....always learning and unlearning in this hobby.....goes with the territory
-Tony
10 degrees of overlap @.050" really isn't a large difference in the grand scheme of things compared to the OP's 5 degrees@.050".
What was the power difference between the step header and straight tube under peak torque if you can remember Tony?
02-19-2015, 08:13 PM
#48
Tony, you were running AFR heads tho, which have a larger exhaust port, larger exhaust valve, and seem to benefit from a smaller header to increase velocity. At least what I've noticed.
The OP is running PRC heads, which are an aftermarket casting, but I don't know if their exhaust ratio is as good as the AFR heads, but they are running the 1.60" exhaust valve. On stock type ported heads and TFS heads, the bigger primary diameter helps almost everywhere over the smaller header given the shorter primary length found on F-Bodies vs the Vette and the smaller 1.57" exhaust valve and smaller exhaust port.
It's a system and the head plays as much a role as the header design. Certain header designs work better with certain heads. The LG Pro 1-3/4" 32" long primary headers seem to work excellent with the AFR heads. But they don't show as strongly against ARH 1-7/8" headers with TFS heads.
For the OP, I'd run straight 1-7/8" headers. I know others have shown a 20rwhp increase on the F-Body going to 1-7/8" headers vs 1-3/4" headers using TSP stock ported castings without losing any torque. But again, the design of the ported stock head is a bit different. You have a 4" stroke though and a strong cam design... I'd go 1-7/8" and see what you pickup. It might be more than 8. And the losses might be pretty minimal.
The OP is running PRC heads, which are an aftermarket casting, but I don't know if their exhaust ratio is as good as the AFR heads, but they are running the 1.60" exhaust valve. On stock type ported heads and TFS heads, the bigger primary diameter helps almost everywhere over the smaller header given the shorter primary length found on F-Bodies vs the Vette and the smaller 1.57" exhaust valve and smaller exhaust port.
It's a system and the head plays as much a role as the header design. Certain header designs work better with certain heads. The LG Pro 1-3/4" 32" long primary headers seem to work excellent with the AFR heads. But they don't show as strongly against ARH 1-7/8" headers with TFS heads.
For the OP, I'd run straight 1-7/8" headers. I know others have shown a 20rwhp increase on the F-Body going to 1-7/8" headers vs 1-3/4" headers using TSP stock ported castings without losing any torque. But again, the design of the ported stock head is a bit different. You have a 4" stroke though and a strong cam design... I'd go 1-7/8" and see what you pickup. It might be more than 8. And the losses might be pretty minimal.
02-20-2015, 12:56 PM
#49
Tony, you were running AFR heads tho, which have a larger exhaust port, larger exhaust valve, and seem to benefit from a smaller header to increase velocity. At least what I've noticed.
The OP is running PRC heads, which are an aftermarket casting, but I don't know if their exhaust ratio is as good as the AFR heads, but they are running the 1.60" exhaust valve. On stock type ported heads and TFS heads, the bigger primary diameter helps almost everywhere over the smaller header given the shorter primary length found on F-Bodies vs the Vette and the smaller 1.57" exhaust valve and smaller exhaust port.
It's a system and the head plays as much a role as the header design. Certain header designs work better with certain heads. The LG Pro 1-3/4" 32" long primary headers seem to work excellent with the AFR heads. But they don't show as strongly against ARH 1-7/8" headers with TFS heads.
For the OP, I'd run straight 1-7/8" headers. I know others have shown a 20rwhp increase on the F-Body going to 1-7/8" headers vs 1-3/4" headers using TSP stock ported castings without losing any torque. But again, the design of the ported stock head is a bit different. You have a 4" stroke though and a strong cam design... I'd go 1-7/8" and see what you pickup. It might be more than 8. And the losses might be pretty minimal.
The OP is running PRC heads, which are an aftermarket casting, but I don't know if their exhaust ratio is as good as the AFR heads, but they are running the 1.60" exhaust valve. On stock type ported heads and TFS heads, the bigger primary diameter helps almost everywhere over the smaller header given the shorter primary length found on F-Bodies vs the Vette and the smaller 1.57" exhaust valve and smaller exhaust port.
It's a system and the head plays as much a role as the header design. Certain header designs work better with certain heads. The LG Pro 1-3/4" 32" long primary headers seem to work excellent with the AFR heads. But they don't show as strongly against ARH 1-7/8" headers with TFS heads.
For the OP, I'd run straight 1-7/8" headers. I know others have shown a 20rwhp increase on the F-Body going to 1-7/8" headers vs 1-3/4" headers using TSP stock ported castings without losing any torque. But again, the design of the ported stock head is a bit different. You have a 4" stroke though and a strong cam design... I'd go 1-7/8" and see what you pickup. It might be more than 8. And the losses might be pretty minimal.
http://www.texas-speed.com/p-7-prc-2...der-heads.aspx
Last edited by Goosecaddy05; 02-20-2015 at 01:26 PM. Reason: looked up valve on afr
02-20-2015, 01:14 PM
#50
Pretty much what martin said the iac is closing too quick. There are many tables to address this. I played with mine for a long time and got it damn near perfect but my light clutch still has some nuisances that I have to deal with. But the problem you describe can be fixed with throttle cracker and massaging of the iac count table.
The throttle cracker allows air in based on rpm and throttle. In some cars it 0's when the tps is at 0 but most fbodys dont do that. By increasing the tc table you can control how fast the rpm drops.
The iac count table tells the pcm how many "counts" or turns open of the iac motor allows X air in. This depends on the iac motor and how much it opens but also the size of the tb passage. The NW although big enough for the motor is still smaller than the stock tb so the count table must be altered to account for that in some cases.
I say some and not all because every car and I mean EVERY car is different lol
The throttle cracker allows air in based on rpm and throttle. In some cars it 0's when the tps is at 0 but most fbodys dont do that. By increasing the tc table you can control how fast the rpm drops.
The iac count table tells the pcm how many "counts" or turns open of the iac motor allows X air in. This depends on the iac motor and how much it opens but also the size of the tb passage. The NW although big enough for the motor is still smaller than the stock tb so the count table must be altered to account for that in some cases.
I say some and not all because every car and I mean EVERY car is different lol
02-20-2015, 01:16 PM
#51
one thing about the afr 215 vs prc 215 also is that on afr's flow numbers they are tested with a 4.06 bore and 1 7/8 exhaust pipe and the prc is tested with a 4.0 bore plate and no exhaust pipe, so the prc should substantially outflow the afr 215 at least on intake and probably match the afr on the exhaust port if they tested both with the same bore plate and exhaust pipe
afr 215 flow chart 4.06 bore plate and 1 7/8 exhaust pipe
Lift Intake Exhaust
.200 154 132
.300 219 180
.400 264 221
.500 297 239
.600 312 246
Prc 215 flow chart
Flow Data:
4.00" Flow Plate - No Exhaust Pipe
LIFT INTAKE FLOW EXHAUST FLOW
.100" 68 CFM 56 CFM
.200" 145 CFM 115 CFM
.300" 214 CFM 167 CFM
.400" 271 CFM 202 CFM
.500" 304 CFM 219 CFM
.600" 318 CFM 238 CFM
.650" 321 CFM 236 CFM
afr 215 flow chart 4.06 bore plate and 1 7/8 exhaust pipe
Lift Intake Exhaust
.200 154 132
.300 219 180
.400 264 221
.500 297 239
.600 312 246
Prc 215 flow chart
Flow Data:
4.00" Flow Plate - No Exhaust Pipe
LIFT INTAKE FLOW EXHAUST FLOW
.100" 68 CFM 56 CFM
.200" 145 CFM 115 CFM
.300" 214 CFM 167 CFM
.400" 271 CFM 202 CFM
.500" 304 CFM 219 CFM
.600" 318 CFM 238 CFM
.650" 321 CFM 236 CFM
02-20-2015, 01:32 PM
#52
That's interesting. I was just looking at the flow numbers for my heads (tested on a 4.00 Bore with 1/2" radius plate and 1 7/8" pipe) and the exhaust flow numbers are way higher than both the AFR and PRC.
.550 305 261
.600 311.4 272
.650 313.6 255
.700 314.9 278
Does this mean that these heads need less or more header? What I mean is will there be a significant increase in power going from 1 3/4 headers to 1 7/8 headers?
.550 305 261
.600 311.4 272
.650 313.6 255
.700 314.9 278
Does this mean that these heads need less or more header? What I mean is will there be a significant increase in power going from 1 3/4 headers to 1 7/8 headers?
02-20-2015, 01:38 PM
#53
It's not wise to compare numbers on heads across different flow benches just as it isn't wise to do so with dyno numbers.
It is worth saying that properly calibrated flow benches are usually similar to one another in the flow numbers they put out, but there is still is the variable of the benches not being one and the same. Same is worth saying for dyno's as well.
I'm sure Tony would echo my thoughts.
It is worth saying that properly calibrated flow benches are usually similar to one another in the flow numbers they put out, but there is still is the variable of the benches not being one and the same. Same is worth saying for dyno's as well.
I'm sure Tony would echo my thoughts.
02-20-2015, 02:05 PM
#54
It's not wise to compare numbers on heads across different flow benches just as it isn't wise to do so with dyno numbers.
It is worth saying that properly calibrated flow benches are usually similar to one another in the flow numbers they put out, but there is still is the variable of the benches not being one and the same. Same is worth saying for dyno's as well.
I'm sure Tony would echo my thoughts.
It is worth saying that properly calibrated flow benches are usually similar to one another in the flow numbers they put out, but there is still is the variable of the benches not being one and the same. Same is worth saying for dyno's as well.
I'm sure Tony would echo my thoughts.
02-20-2015, 03:01 PM
#55
Well that's the question right. Since it's a system, would a large exhaust valve and exhaust runner need a larger diameter primary? A longer primary? A longer collector? A larger diameter collector? Merge? Velocity spike?
There's mathematical formulas for finding the "optimal" header length and primary diameter using A. Graham Bell's formulas. A 346 that lives under 7000 RPM is a 32" long 1-3/4" primary to provide optimal torque and HP. One reason why the LG Pro headers were so good - that's their dimensions. The issue is those formulas don't take into consideration the port dynamics of the head. Larger exhaust ports with larger valves lose some velocity (just like an oversized intake valve and runner volume), but should a smaller header be used to compensate? A larger header to augment the top-end power?
Phoenix, I'd say the added header will not hurt you. it will probably increase the top end.
There's mathematical formulas for finding the "optimal" header length and primary diameter using A. Graham Bell's formulas. A 346 that lives under 7000 RPM is a 32" long 1-3/4" primary to provide optimal torque and HP. One reason why the LG Pro headers were so good - that's their dimensions. The issue is those formulas don't take into consideration the port dynamics of the head. Larger exhaust ports with larger valves lose some velocity (just like an oversized intake valve and runner volume), but should a smaller header be used to compensate? A larger header to augment the top-end power?
Phoenix, I'd say the added header will not hurt you. it will probably increase the top end.
02-20-2015, 03:14 PM
#56
Thanks Jake! I know one of the main benefits of the AFR 205cc heads is their great exhaust flow. I believe that's the reason those heads have always done so well with single pattern cams, or cams with a 2 to 4 degree split. At the same time, I've probably seen the most impressive results when AFR heads are paired with one of the LG cams, which seem to be a much larger split/higher duration, than what Tony would spec. for those heads. I know I can't compare my heads to AFR heads, but from what I've seen, my AI Dart/RHS heads seem to be the closest in regards to exhaust flow, as most of the other heads out there have relatively low exhaust flow numbers. For the cost of the Speed Engineering 1 7/8" headers, I really can't lose buying and installing them. Hell, I can sell my Stainless Works headers and may only be out less than a $100 after it's all said and done.
02-20-2015, 03:35 PM
#57
11 Second Club
Thread Starter
Pretty much what martin said the iac is closing too quick. There are many tables to address this. I played with mine for a long time and got it damn near perfect but my light clutch still has some nuisances that I have to deal with. But the problem you describe can be fixed with throttle cracker and massaging of the iac count table.
The throttle cracker allows air in based on rpm and throttle. In some cars it 0's when the tps is at 0 but most fbodys dont do that. By increasing the tc table you can control how fast the rpm drops.
The iac count table tells the pcm how many "counts" or turns open of the iac motor allows X air in. This depends on the iac motor and how much it opens but also the size of the tb passage. The NW although big enough for the motor is still smaller than the stock tb so the count table must be altered to account for that in some cases.
I say some and not all because every car and I mean EVERY car is different lol
The throttle cracker allows air in based on rpm and throttle. In some cars it 0's when the tps is at 0 but most fbodys dont do that. By increasing the tc table you can control how fast the rpm drops.
The iac count table tells the pcm how many "counts" or turns open of the iac motor allows X air in. This depends on the iac motor and how much it opens but also the size of the tb passage. The NW although big enough for the motor is still smaller than the stock tb so the count table must be altered to account for that in some cases.
I say some and not all because every car and I mean EVERY car is different lol
Right now I think I'm leaning toward the 1 7/8". A loss in tq, gain in hp sounds sweeter. With the 4" stroke I think I'll still be better than a 347 in tq.
Thanks guys. Keep it coming.
Last edited by SoFla01SSLookinstok; 02-16-2016 at 10:25 AM.
02-20-2015, 03:48 PM
#58
Well that's the question right. Since it's a system, would a large exhaust valve and exhaust runner need a larger diameter primary? A longer primary? A longer collector? A larger diameter collector? Merge? Velocity spike?
There's mathematical formulas for finding the "optimal" header length and primary diameter using A. Graham Bell's formulas. A 346 that lives under 7000 RPM is a 32" long 1-3/4" primary to provide optimal torque and HP. One reason why the LG Pro headers were so good - that's their dimensions. The issue is those formulas don't take into consideration the port dynamics of the head. Larger exhaust ports with larger valves lose some velocity (just like an oversized intake valve and runner volume), but should a smaller header be used to compensate? A larger header to augment the top-end power?
Phoenix, I'd say the added header will not hurt you. it will probably increase the top end.
There's mathematical formulas for finding the "optimal" header length and primary diameter using A. Graham Bell's formulas. A 346 that lives under 7000 RPM is a 32" long 1-3/4" primary to provide optimal torque and HP. One reason why the LG Pro headers were so good - that's their dimensions. The issue is those formulas don't take into consideration the port dynamics of the head. Larger exhaust ports with larger valves lose some velocity (just like an oversized intake valve and runner volume), but should a smaller header be used to compensate? A larger header to augment the top-end power?
Phoenix, I'd say the added header will not hurt you. it will probably increase the top end.
I have found Pipe Max to be extremely accurate in modeling certain parameters. Meaux is no dummy...
02-22-2015, 06:55 PM
#59
The car has been sitting for the past couple days. My tuner is super busy with projects.
This is way better than just buying what you think is right. Communication, evaluation, & information. Awesome!
Right now I think I'm leaning toward the 1 7/8". My car is a DD but a, loss in tq, gain in hp sounds sweeter. With the 4" stroke I think I'll still be better than a 347 in tq.
Thanks guys. Keep it coming.
This is way better than just buying what you think is right. Communication, evaluation, & information. Awesome!
Right now I think I'm leaning toward the 1 7/8". My car is a DD but a, loss in tq, gain in hp sounds sweeter. With the 4" stroke I think I'll still be better than a 347 in tq.
Thanks guys. Keep it coming.
If you were running stock cubes the loss of midrange torque might have presented more of a question.....in your case that's not whats going on.....horsepower wins races.....torque pulls trailers.....which are you doing??
__________________
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
02-22-2015, 08:52 PM
#60
For poops and giggles I can run this engine through Pipe Max and see what it recommends for primary length and diameter. It takes into account the exhaust port length as well.
I have found Pipe Max to be extremely accurate in modeling certain parameters. Meaux is no dummy...
I have found Pipe Max to be extremely accurate in modeling certain parameters. Meaux is no dummy...