What heads are people using With HSR
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Re: What heads are people using With HSR
Mike
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Re: What heads are people using With HSR
Well, the AFR heads I had bought were angle head designed and I couldnt get a few plugs in correctly as well as put the boots on them. I had to cut off the header flanges and buy a few pieces of 1 3/4" tube from Summit and redesign the primaries near the head so I could get more plug clearance. It took a little trial and error but I got it done and then shipped them off to JET HOT. I did not have any issues with them besides the plug clearance.
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Re: What heads are people using With HSR
I've been running AFR heads for the past 10 years. If the car works and the compression isn't high, I'd look at a small blower like a v3-s.
-- Joe
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Re: What heads are people using With HSR
I had an ATI. I won't buy another one...
-- Joe
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Re: What heads are people using With HSR
Kinda sorta. You don't have TPI, so the TPI discharge tube would be a pita to make work with the HSR.
I'm saying buy the SBC "tuner kit" which is the mounting assembly, head unit, air cleaner. Then plumb it to your throttle body. Plenty of threads on it in the power adder forum.
The procharger bracket setup is garbage for thirdgens, it flexes, belts fly, etc. The P1SC and D1SC head units are not very efficient, and absolutely require intercooling.
If you are into fabricating, you can do a passenger side mount like I did, but I did that for a specific purpose that most people don't care about.
With all that said though, 10.5:1 compression is too high IMO for forced induction. When I had a C4 with a Powerdyne, I was at 10.5:1 with trickflow heads and I was always chasing detonation.
-- Joe
I'm saying buy the SBC "tuner kit" which is the mounting assembly, head unit, air cleaner. Then plumb it to your throttle body. Plenty of threads on it in the power adder forum.
The procharger bracket setup is garbage for thirdgens, it flexes, belts fly, etc. The P1SC and D1SC head units are not very efficient, and absolutely require intercooling.
If you are into fabricating, you can do a passenger side mount like I did, but I did that for a specific purpose that most people don't care about.
With all that said though, 10.5:1 compression is too high IMO for forced induction. When I had a C4 with a Powerdyne, I was at 10.5:1 with trickflow heads and I was always chasing detonation.
-- Joe
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Re: What heads are people using With HSR
I am using AFR 210's on a 414CI sbc. With a 236/242 cam it made 419WHP.
I ended up changing cams due to a drivability issue I couldn't get tuned out and went with a 229/237 cam and overall drivability is much better. It actually picked up a little speed in the 1/8th mile but I haven't dyno'ed yet.
If I were doing it over and especially with less CI I would run AFR 195 comp ports. In the end the few hundred more for the comp version isn't a big deal plus the come with better springs than the street version.
My motor responded well to a little less overlap on the cam. The first cam had 70* overlap (15* @ .050) and the second has 57* overlap (7* @ .050). I also had it ground with 4/7 swap firing order. I think the common plenum and front 4/rear 4 grouping on the HSR causes some issues with overlap. If it was a dual plane intake it would have probably tolerated the first cam better.
With a 350 I would go AFR 195 comp port heads and probably a 268 XFI cam or a custom cam of similar specs. Maybe 224/230 QNI lobes. Grind it to give ~5-7* overalp @ .050.
Note; fast rate cam lobes and high ratio roller rockers can be noisy and that should be taken into consideration. If you want to keep it quiet you may want to stay with XE or similar profiles.
I ended up changing cams due to a drivability issue I couldn't get tuned out and went with a 229/237 cam and overall drivability is much better. It actually picked up a little speed in the 1/8th mile but I haven't dyno'ed yet.
If I were doing it over and especially with less CI I would run AFR 195 comp ports. In the end the few hundred more for the comp version isn't a big deal plus the come with better springs than the street version.
My motor responded well to a little less overlap on the cam. The first cam had 70* overlap (15* @ .050) and the second has 57* overlap (7* @ .050). I also had it ground with 4/7 swap firing order. I think the common plenum and front 4/rear 4 grouping on the HSR causes some issues with overlap. If it was a dual plane intake it would have probably tolerated the first cam better.
With a 350 I would go AFR 195 comp port heads and probably a 268 XFI cam or a custom cam of similar specs. Maybe 224/230 QNI lobes. Grind it to give ~5-7* overalp @ .050.
Note; fast rate cam lobes and high ratio roller rockers can be noisy and that should be taken into consideration. If you want to keep it quiet you may want to stay with XE or similar profiles.
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Re: What heads are people using With HSR
Well, the AFR heads I had bought were angle head designed and I couldnt get a few plugs in correctly as well as put the boots on them. I had to cut off the header flanges and buy a few pieces of 1 3/4" tube from Summit and redesign the primaries near the head so I could get more plug clearance. It took a little trial and error but I got it done and then shipped them off to JET HOT. I did not have any issues with them besides the plug clearance.
EDIT: Just realized that the wires wren't connected in that picture!
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Re: What heads are people using With HSR
AFR 210 angled plug and Hooker shorty headers. No problem with plug clearance & 90* boots. I do have to use a short socket and wrench on all plugs for removal and 6 & 8 can only be replaced from underneath but header clearance is fine. I actually think it is better than the straight plug heads clearance. Either type required a stubby socket and wrench to R&R.
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Car: '88 Formula, '94 Corvette, '95 Bird
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Transmission: TKX, 4L60E
Axle/Gears: 3.42, 3.23
Re: What heads are people using With HSR
AFR 210 angled plug and Hooker shorty headers. No problem with plug clearance & 90* boots. I do have to use a short socket and wrench on all plugs for removal and 6 & 8 can only be replaced from underneath but header clearance is fine. I actually think it is better than the straight plug heads clearance. Either type required a stubby socket and wrench to R&R.
-- Joe
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Re: What heads are people using With HSR
I just cut a 1/2 drive socket in half and use the hex portion on the end and a wrench. A 3/8 drive wasn't large enough to let the plug pass through. All you really need is about a 1/2 turn then run them in/out by hand. Summit sells a stubby socket for ~$25 but ~$6 and a hack saw will get you there too. Each plug requires a certain approach and body positioning to get hand access. But like you said, once you have your plan down I can do them in 30 minutes or less including jacking the car up for 6 & 8.
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