Relocated exhaust port T1 Style.
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70dragbug
- Posts: 534
- Joined: Sun Oct 27, 2002 1:01 am
I agree Farmer.So far the Remmele Heads are the best I´ve seen for the T4.He built a 3050cc T4 a few months ago that had 288 HP at 5500 rpm at the wheels on a rolling dyno and there is room for more.It did have EFI with 52mm throttlebodies.Top speed on the Autobahn was 260 Km/h!With a 4 speed 3.88/ 0.82! I´m anxious too see how Jake´s heads will perform,with the amount of testing he does and his dedication I´m sure it will be a top notch product.I´m also anxious to see Wally´s Apfelbeck heads aswell.I´d say there are some pretty good times ahead for the T4 crowd!
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MASSIVE TYPE IV
- Posts: 20132
- Joined: Fri Jul 07, 2000 12:01 am
Sounds good!
My 2980cc engine should make the same kind of power with my new heads. 280 is actually my goal, but the first generation engine that will be used to compare a set of worked over 2.0 heads to ours probably won't make it.....
The second generation engine will due to lighter pistons that won't need any valve reliefs due to the head design...
My 2980cc engine should make the same kind of power with my new heads. 280 is actually my goal, but the first generation engine that will be used to compare a set of worked over 2.0 heads to ours probably won't make it.....
The second generation engine will due to lighter pistons that won't need any valve reliefs due to the head design...
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HAM Inc
- Posts: 591
- Joined: Wed Jan 14, 2004 7:33 am
Plenty of E & F Prod engines turning over 7500 reliably. Their is no design or mechanical reason the t-IV can't turn what the tI can turn, once you start modifying. Both are H4 pushrod engines. And if the O.E. heads are retained, modified or stock, the typeIV heads move more air, meaning they will make power at higher revs than a typeI. Not partisan squabble here, I like both engines. Just the facts.
No need to create an exhaust port that sails beyond 80% of the intakes flow at 28" depression. Most successful N.A. race engine builders stick religiously to 75%. (Drag racing MAY be an exception). This is doable on O.E. TypeIV heads. I have over shot the % and seen 85%. Then had to struggle to bring the intake #'s up to balance the head. I think because the stock ex ports are so crappy (2.0 914 excluded) folks have this idea it sinks the whole package unless drastic action is taken. This is just not the case. For street applications it doesn't take much to open the exhaust port on any O.E. casting to balance the in. & ex. ports.
For folks that want more than can be squeezed from the O.E. units, the flow #'s on Jakes MassIVe prototype head (with typeI style ex.) are incredible. To the point that new bottom end components are currntly being developed to take advantage of the heads potential. Chris Foley is developing an exhaust for the package.
No need to create an exhaust port that sails beyond 80% of the intakes flow at 28" depression. Most successful N.A. race engine builders stick religiously to 75%. (Drag racing MAY be an exception). This is doable on O.E. TypeIV heads. I have over shot the % and seen 85%. Then had to struggle to bring the intake #'s up to balance the head. I think because the stock ex ports are so crappy (2.0 914 excluded) folks have this idea it sinks the whole package unless drastic action is taken. This is just not the case. For street applications it doesn't take much to open the exhaust port on any O.E. casting to balance the in. & ex. ports.
For folks that want more than can be squeezed from the O.E. units, the flow #'s on Jakes MassIVe prototype head (with typeI style ex.) are incredible. To the point that new bottom end components are currntly being developed to take advantage of the heads potential. Chris Foley is developing an exhaust for the package.
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70dragbug
- Posts: 534
- Joined: Sun Oct 27, 2002 1:01 am
I must admit I like both engines too.The main thing I like about the T1 is the product availability.I like the T4 because of its torque and the ability to build it big (above 2.5 liters) and you don´t have to rev the tits off it to get a lot of power.
Len,what´s the max flow (in CFM) that you´ve seen on a T4 head?
Jake, I think 280 is realistic- but not for your dyno
Len,what´s the max flow (in CFM) that you´ve seen on a T4 head?
Jake, I think 280 is realistic- but not for your dyno
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Joe vw
- Posts: 770
- Joined: Tue Sep 25, 2001 12:01 am
Hi Len,
Why is it that smaller carbs work better with the type 4? As Jake has noted on his dyno 44s make more power than 48s. My 1.7 I have liked dual 32ndix carbs better than dual Weber 40s. It just seems that it's easier to bolt together a type1 that pulls to the redline where the type 4 flattens out. My FAT 2.6 pulls very hard off the line and goes pretty good but it flattens out on the top end. ( Jake, had you been around when I bought my FAT engine you would have got my money).
How can a stock displacement 2.0 be made to handle 48IDAs and pull to the moon like a type1? If you recall back in the 70s there were high compression race only type1 1.8s running 11 seconds. Some of us would be interested in building a smaller type 4 for drags,on the cheap.
While good flow numbers can be had on a type 4 exhaust port, does it set up turbulance at higher air speed? Why the need for split duration cams? How can similar performance be had with straight up cams like a type1? Other than head sealing issues it's been said on this forum turbo performance isn't as good as a type1, why?
Are people just wrecking the performance by improper porting?
Untill someone writes a book on performance type4 heads and proven combos with dyno numbers. It will be left to the dedicated type4 engine builders/shops to set people straight and the rest will continue to make the same mistakes. It's been around 35 years since the first type4 was made, and still nothings written down.
I know shops like Jakes don't want to give away all their hard earned info but it seems even choosing a cam/head combo is black art unless your talking about the most mild of performance. When it comes to backyard builds I think your type1 HP sucess rate will be higher compared to a type 4 for your dollar. That said, I appreciate all the info shared on this forum.
Why is it that smaller carbs work better with the type 4? As Jake has noted on his dyno 44s make more power than 48s. My 1.7 I have liked dual 32ndix carbs better than dual Weber 40s. It just seems that it's easier to bolt together a type1 that pulls to the redline where the type 4 flattens out. My FAT 2.6 pulls very hard off the line and goes pretty good but it flattens out on the top end. ( Jake, had you been around when I bought my FAT engine you would have got my money).
How can a stock displacement 2.0 be made to handle 48IDAs and pull to the moon like a type1? If you recall back in the 70s there were high compression race only type1 1.8s running 11 seconds. Some of us would be interested in building a smaller type 4 for drags,on the cheap.
While good flow numbers can be had on a type 4 exhaust port, does it set up turbulance at higher air speed? Why the need for split duration cams? How can similar performance be had with straight up cams like a type1? Other than head sealing issues it's been said on this forum turbo performance isn't as good as a type1, why?
Are people just wrecking the performance by improper porting?
Untill someone writes a book on performance type4 heads and proven combos with dyno numbers. It will be left to the dedicated type4 engine builders/shops to set people straight and the rest will continue to make the same mistakes. It's been around 35 years since the first type4 was made, and still nothings written down.
I know shops like Jakes don't want to give away all their hard earned info but it seems even choosing a cam/head combo is black art unless your talking about the most mild of performance. When it comes to backyard builds I think your type1 HP sucess rate will be higher compared to a type 4 for your dollar. That said, I appreciate all the info shared on this forum.
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MASSIVE TYPE IV
- Posts: 20132
- Joined: Fri Jul 07, 2000 12:01 am
Coming very soon the "Black art" won't be quite so black.....
AND Len will have his own portion of the Performance Type IV engine build video, as well as a section in my book that I have been working on for 3 years off and on...
Yes, may people have been doing impropoer port jobs to these engines for years, because they "look better" that way...
BTW, your 2.6 probably doesn't have enough head to rev any higher. he big displacement moves the max amount of air through those ports at alot lower RPM than a smaller engine would...
Not to bag on your engine, but I'll bet you that our 2316 with Lensheqds would out rev, and out perform the 2.6 at all levels above 4,000 RPM, and produce more net HP in the usable RPM range- with better throttle response.
Not even a 2700 needs the mass air from an IDA carb in what we have seen...
I probably was around when you bought your FAT engine, but you just didn't know it..
AND Len will have his own portion of the Performance Type IV engine build video, as well as a section in my book that I have been working on for 3 years off and on...
Yes, may people have been doing impropoer port jobs to these engines for years, because they "look better" that way...
BTW, your 2.6 probably doesn't have enough head to rev any higher. he big displacement moves the max amount of air through those ports at alot lower RPM than a smaller engine would...
Not to bag on your engine, but I'll bet you that our 2316 with Lensheqds would out rev, and out perform the 2.6 at all levels above 4,000 RPM, and produce more net HP in the usable RPM range- with better throttle response.
Not even a 2700 needs the mass air from an IDA carb in what we have seen...
I probably was around when you bought your FAT engine, but you just didn't know it..
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Joe vw
- Posts: 770
- Joined: Tue Sep 25, 2001 12:01 am
MASSIVE TYPE IV wrote: Not to bag on your engine, but I'll bet you that our 2316 with Lensheqds would out rev, and out perform the 2.6 at all levels above 4,000 RPM, and produce more net HP in the usable RPM range- with better throttle response.
I'm under no illusions, I'm running Porsche 2.0 48x38 valve heads I'm wondering if any improvement can be made to them. Can a larger exhaust valve work with these heads or is 38mm the largest effective size? I plan on building an even better exhaust system. I built the current one to replace the (FAT made sedan one wasn't very good) this was a definate improvement.
I'm using 44 Webers, No complaints about throttle response though.
How can a high strung 1600 type1 handle 48idas but a huge type 4 can't?
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70dragbug
- Posts: 534
- Joined: Sun Oct 27, 2002 1:01 am
Thanks Len,
Those are impressive numbers! That´s in the same range as a CNC comp. eliminator head! The most popular T4 engines around here are usually 2366cc or near stock 2 liter up to 120 HP.That´s probably why I haven´t seen too many high revving engines here.
In addition to Joe VW´s question,could it be that the T4 likes a smaller carb because there are limitations to header size at the head? 40mm is the max at the port,then after the pushrod you can flare out to a larger diameter.Maybe a problem with siphoning the exhaust gasses out?
Those are impressive numbers! That´s in the same range as a CNC comp. eliminator head! The most popular T4 engines around here are usually 2366cc or near stock 2 liter up to 120 HP.That´s probably why I haven´t seen too many high revving engines here.
In addition to Joe VW´s question,could it be that the T4 likes a smaller carb because there are limitations to header size at the head? 40mm is the max at the port,then after the pushrod you can flare out to a larger diameter.Maybe a problem with siphoning the exhaust gasses out?
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farmer
- Posts: 2399
- Joined: Fri Dec 07, 2001 12:01 am
Who says they can´t ? The quesation is, do they make more power with IDA´s ?Joe vw wrote: How can a high strung 1600 type1 handle 48idas but a huge type 4 can't?
The answer in most cases is no, or very little. The only exception to that are pure race engines.
A friend of mine from GB once tried to compare carbs a 2275 T1. FK8, 42*37, 9,5-1 CR etc etc. He first had a set of 45 Dells w. 36 vnturies on, and it pulled 167 hp (I forgot the rpms) He then tried with a set of IDA´s and found best performance w. 37 mm venturies. Then he pulled 171 hp max., but lost up to 6 hp below 3300 rpm.
Track times was almost the same, but the IDA version did reduce the time withabout 0,1 on the quarter.
Same guy tried a comparison on a mild 2056 cc. T4, producing 128 hp max.w IDA´s and 127 hp w. 40 Dells. But fuel economy was improoved by 30% with the Dells.
T.
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HAM Inc
- Posts: 591
- Joined: Wed Jan 14, 2004 7:33 am
Since my focus for years now has been only heads, I can't say with authority why 48IDA's have a bad rep with the typeIV. The most likely explanation is that the IDA's are being bolted on combos that work well with other carbs, but may not be right for the IDA. The more likely is that the carbs aren't being properly set up for the combo. Some folks had problems with 48IDA's on TypeI's for this same reason. People would bolt them on with the venturi/jet package they shipped with new, or if used whatever was in them on the last engine they were on. That rarely worked out.
OVer the years since its introduction the 48 IDA has proven to be a very versatile carb. Cobra's with 289 Fords equipped with 48IDA's were great performers, same with small block and big block Chevy's, I've seen them used on dirt track inline six cylinder Fords with success. In the seventies my Dad had success at New Symyrna with a 1584 TypeI equipped with dual 48IDA's.
Carbs don't know what sort of engine they are on. If the carb is set up for the application and the combo is right a 48IDA, in my opinion, will work on pretty much any engine.
As for the ex. restriction caused by the pushrod tubes, I always flow heads with a stub. The flow #'s I've seen don't support that the restriction is significant enough to limit revs. And considering the velocity in that area at high speeds I doubt there would be much to be gained by somehow elminating it. With regard to turbulence, if it is present in a port it will show up in diminished flow #'s. Ofcourse a flowbench can't always accurately predict conditions in a hot, pulsing port. That said, the benches value as a tuning tool is to prepare balanced heads and help with cam selection as well as tune for the intended RPM range.
48mm intakes are to large for the port. I don't prep O.E. castings for anything larger than 46mm. The port chokes between the entry and the bowl area beneath the valve. The entry can be welded and enlarged, the bowl can be opened paper thin for the 48 valve, but the middle portion of the port is limited. Fuel mixture takes a dump if proper shape is not maintained. I believe 48mm intakes are like fishing lures designed to catch fisherman, not fish.
OVer the years since its introduction the 48 IDA has proven to be a very versatile carb. Cobra's with 289 Fords equipped with 48IDA's were great performers, same with small block and big block Chevy's, I've seen them used on dirt track inline six cylinder Fords with success. In the seventies my Dad had success at New Symyrna with a 1584 TypeI equipped with dual 48IDA's.
Carbs don't know what sort of engine they are on. If the carb is set up for the application and the combo is right a 48IDA, in my opinion, will work on pretty much any engine.
As for the ex. restriction caused by the pushrod tubes, I always flow heads with a stub. The flow #'s I've seen don't support that the restriction is significant enough to limit revs. And considering the velocity in that area at high speeds I doubt there would be much to be gained by somehow elminating it. With regard to turbulence, if it is present in a port it will show up in diminished flow #'s. Ofcourse a flowbench can't always accurately predict conditions in a hot, pulsing port. That said, the benches value as a tuning tool is to prepare balanced heads and help with cam selection as well as tune for the intended RPM range.
48mm intakes are to large for the port. I don't prep O.E. castings for anything larger than 46mm. The port chokes between the entry and the bowl area beneath the valve. The entry can be welded and enlarged, the bowl can be opened paper thin for the 48 valve, but the middle portion of the port is limited. Fuel mixture takes a dump if proper shape is not maintained. I believe 48mm intakes are like fishing lures designed to catch fisherman, not fish.
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Guest
Ham sed:
"I believe 48mm intakes are like fishing lures designed to
catch fisherman, not fish."
BUWAHAHAHAHAHHAHA!
Well sed Len!
You have probably seen more heads destroyed(Ok, cracked between the valves)
by going with the 48X38 combo?
Even 46X40s would take either a large CC or high RPM engine to properly
utilize.
Don
"I believe 48mm intakes are like fishing lures designed to
catch fisherman, not fish."
BUWAHAHAHAHAHHAHA!
Well sed Len!
You have probably seen more heads destroyed(Ok, cracked between the valves)
by going with the 48X38 combo?
Even 46X40s would take either a large CC or high RPM engine to properly
utilize.
Don
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Joe vw
- Posts: 770
- Joined: Tue Sep 25, 2001 12:01 am
Look at the top cars on the CAL-Look forum and with the exception of TURBOs they're all running IDAs. And why would someone bore them out if there was no improvement? One or two example of someones street engine does not prove the rule.
I would like to see a smaller high strungT4 compete with the 2300 type 1s on that forum and at the track. I'm not trying to stir contoversy, I like both engine types and also the Wasser. This is the place to look for answers.
I know there are a few t4 drag racers, very few though. Road racing is great, but most are not seen to the same degree as a drag/show type event.
Jake building his monster is a good step to be seen and a boost for type4 intrest.
I would like to see a smaller high strungT4 compete with the 2300 type 1s on that forum and at the track. I'm not trying to stir contoversy, I like both engine types and also the Wasser. This is the place to look for answers.
I know there are a few t4 drag racers, very few though. Road racing is great, but most are not seen to the same degree as a drag/show type event.
Jake building his monster is a good step to be seen and a boost for type4 intrest.
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MASSIVE TYPE IV
- Posts: 20132
- Joined: Fri Jul 07, 2000 12:01 am
A 13:1 full drag race engine with a Type I exhaust port would definately benefit from an IDA, but not a TIV..
I have never seen an IDA outperform a smaller carb on a street Type IV. The last engine I used a set of IDAs on had less power than its counterpart built a few weeks before that ran a 35mm Dell..
My 3.0 engine with my heads would benefit from IDAS, but its getting 52mm Throttle bodies and Injection instead. I may test it with a set of IDAS Vs. a set of 48 dells just to see the differences.
Bigger is not better, and thats the case with the air volume that the Ttype IV wants. Velocity is key with the stock head and too much is way too much in many cases.
The main reason why most of my customers go for a TIV is for better drivability and more usable power in the low and midrange. A set of IDAS totally defeats that purpose and makes for a car that is pretty much "off or on" and sucks to drive for a daily commuter with more power.
If you want IDAS buy a Type I.
I have never seen an IDA outperform a smaller carb on a street Type IV. The last engine I used a set of IDAs on had less power than its counterpart built a few weeks before that ran a 35mm Dell..
My 3.0 engine with my heads would benefit from IDAS, but its getting 52mm Throttle bodies and Injection instead. I may test it with a set of IDAS Vs. a set of 48 dells just to see the differences.
Bigger is not better, and thats the case with the air volume that the Ttype IV wants. Velocity is key with the stock head and too much is way too much in many cases.
The main reason why most of my customers go for a TIV is for better drivability and more usable power in the low and midrange. A set of IDAS totally defeats that purpose and makes for a car that is pretty much "off or on" and sucks to drive for a daily commuter with more power.
If you want IDAS buy a Type I.
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Frallan
- Posts: 667
- Joined: Sun Mar 30, 2003 12:01 am
Just for curiosity I could not resist to show my T4/T1 or whatever you wish to call it, T4 heads with relocated ports.
In fact in the mid 80's it was several Rally cross T4 cars in Sweden with relocated exhaust ports T1 style utilising T1 "over the counter" exhaust systems.
I owned a pair myself but unfortunately the quality of these heads were not very good and far away from the water cooled ones in the pictures linked.
Today I see no reason to do it. Only one exception, if you are a welder by profession and like to play with this on your hobby time.
http://www.shoptalkforums.com/viewtopic ... 113#370113
In fact in the mid 80's it was several Rally cross T4 cars in Sweden with relocated exhaust ports T1 style utilising T1 "over the counter" exhaust systems.
I owned a pair myself but unfortunately the quality of these heads were not very good and far away from the water cooled ones in the pictures linked.
Today I see no reason to do it. Only one exception, if you are a welder by profession and like to play with this on your hobby time.
http://www.shoptalkforums.com/viewtopic ... 113#370113